ALBERT

Description: A solid-state microwave generators system is considered as an alternative to the magnetron, in order to inject electromagnetic energy into the cavity of a microwave oven for domestic use. Over current devices, the use of solid state technology allows one to control the frequency and phase of the electromagnetic field generated. Considering a simplified cavity with 2 solid state sources, the influence of the electrical parameters on maximum efficiency obtainable in the process of microwave heating is investigated. By varying the frequency, different values of optimal phases and different values of maximum efficiency are detected. Moreover, the procedure is repeated with varying the position of one source port and the influence of geometry on the system performance is evaluated. Our results demonstrate that the ability to control the electrical quantities of a microwave heating process makes it possible to obtain better results in terms of energy efficiency over the current poorly controllable systems. Content Type Journal Article Pages - DOI 10.3233/JAE-141764 Authors A. Więckowski, Institute of Radioelectronics, Warsaw University of Technology, Warsaw, Poland P. Korpas, Institute of Radioelectronics, Warsaw University of Technology, Warsaw, Poland M. Krysicki, Institute of Radioelectronics, Warsaw University of Technology, Warsaw, Poland F. Dughiero, Department of Industrial Engineering, University of Padova, Padova, Italy M. Bullo, Department of Industrial Engineering, University of Padova, Padova, Italy F. Bressan, Department of Industrial Engineering, University of Padova, Padova, Italy C. Fager, Department of Microtechnology and Nanoscience, Chalmers University of Technology, Göteborg, Sweden Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Nowadays, the induction heating market is continuously growing due to its benefits including precise output power control, reduced heating times, and cleanness. The domestic induction heating application, based on the same principle, includes some extra features such as the controlled temperature profiles or over-temperature detection for an outstanding cooking process. Because of the high power density and the reduced cooling capabilities, efficiency becomes critical in this application. This paper introduces some techniques to improve the efficiency of the induction heating power converters. The proposed converters are analyzed, including the main losses sources, proving that the proposed solution improves the overall efficiency while the component count and cost are keep to reasonable values. Content Type Journal Article Pages - DOI 10.3233/JAE-141760 Authors H. Sarnago, Departamento de Ingeniería Electrónica y Comunicaciones, Universidad de Zaragoza, Zaragoza, Spain O. Lucía, Departamento de Ingeniería Electrónica y Comunicaciones, Universidad de Zaragoza, Zaragoza, Spain A. Mediano, Departamento de Ingeniería Electrónica y Comunicaciones, Universidad de Zaragoza, Zaragoza, Spain J. M. Burdío, Departamento de Ingeniería Electrónica y Comunicaciones, Universidad de Zaragoza, Zaragoza, Spain Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: On account of ANSYS Classic, ANSYS Fluent and ANSYS CFX-Post external coupling a new approach for joined simulation of liquid metal flow, free surface dynamics and electromagnetic (EM) field in induction furnaces is developed. The model is adjusted for the case of EM levitation and extended on 3D consideration with application of standard k-ω Shear Stress Transport (SST) or précised Large Eddy Simulation (LES) turbulence description. Calculated steady state free surface shapes of molten metal are compared to other models and experimental measurements in traditional and EM levitation induction furnaces. Calculated free surface dynamics of melt is compared to analytical estimation of free surface oscillation period. Parameter studies performed in ICF and conventional EM levitation setup briefly illustrate capabilities of the model and demonstrate the influence of current, frequency, surface tension and viscosity on free surface dynamics and steady shape of the melt in 2D approximation. Finally, full 3D calculation of free surface dynamics in ICF using k-ω SST and LES turbulence models is performed and the impact of turbulence model on meniscus is discussed. Content Type Journal Article Pages - DOI 10.3233/JAE-141757 Authors Sergejs Spitans, Institute of Electrotechnology, Leibniz University of Hannover, Hannover, Germany Egbert Baake, Institute of Electrotechnology, Leibniz University of Hannover, Hannover, Germany Bernard Nacke, Institute of Electrotechnology, Leibniz University of Hannover, Hannover, Germany Andris Jakovics, Laboratory for Mathematical Modelling of Environmental and Technological Processes, University of Latvia, Riga, Latvia Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: In the present paper, a new numerical model for calculating martensite microstructure in induction surface hardening processes is introduced. The model was developed with the help of the Department of Electrotechnology and Converter Engineering (LETI). It takes into account the heating as well as the quenching process and uses the temperature history of a work piece to calculate martensite formation. The calculation is based on an empirical equation found by Koistinen and Marburger [1]. A comparison between the heat distribution within a work piece at the end of the heating process and the distribution of martensite after quenching is performed for different process parameters. Thus, it is determined, in which case the temperature distribution is sufficient to predict the hardened layer and in which case the microstructure has to be calculated to receive accurate results. The model is verified by comparing simulation results with different experiments. Content Type Journal Article Pages - DOI 10.3233/JAE-141753 Authors D. Schlesselmann, Institute of Electrotechnology, Leibniz University of Hannover, Hannover, Germany A. Nikanorov, Institute of Electrotechnology, Leibniz University of Hannover, Hannover, Germany A. Nikanorov, Institute of Electrotechnology, Leibniz University of Hannover, Hannover, Germany S. Galunin, Department of Electrotechnology and Converter Engineering, Petersburg, Russia M. Schön, Daimler AG, Technology Management TransAxle, Mercedesplatz, Kassel, Germany Z. Yu, Institute of Materials Science, Leibniz University of Hannover, Garbsen, Germany Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: A laboratory implementation of a two-phase travelling wave induction heating setup is described. The focus is the development of a versatile power control system for multi-coil experiments and parameter studies. The drive system features high temporal accuracy, full real-time controllability, and integrated measurement technology, analyzed step wise. The performance was tested using a full pitch travelling wave inductor based on litz wire with a flux concentrator from a powder material. Thermographic images from the experiments are presented and the results are compared with simulations. The challenges related to multi-coil configurations are explained, many of which are difficult to predict from simulations. Content Type Journal Article Pages - DOI 10.3233/JAE-141762 Authors Kenneth Frogner, Division of Production and Materials Engineering, Lund University, Lund, Sweden Tord Cedell, Division of Production and Materials Engineering, Lund University, Lund, Sweden Mats Andersson, Division of Production and Materials Engineering, Lund University, Lund, Sweden Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Induction cooktops are more and more used in the houses with increasing market in comparison with gas cooktops and resistance or halogen cooktops. The main reasons for this are the higher energy efficiency, the low heating times, the controllability of the power delivered to the pot, the safety with reference to the low temperature of the glass, the superior cleanability. The main core of the Induction Hob (IH) is constituted by the power electronics board and the inductor which are strictly correlated in the sense that the frequency converter (the frequency operating range is 20–100 kHz) must be designed in order to correctly resonate with the coil in order to achieve its optimum efficiency over the broadest possible operation range; this means that the inductor must be designed in order to fulfill the Zero Voltage switching condition of the frequency converter over the whole range of operation. These requirements are much more important in the quasi resonant converters for the limitations in the controllability of soft switch mode of solid state switching. In the paper a design procedure based on a fully 3D FEM model of the inductor coupled with the frequency converter circuit is presented. The simulation results will be discussed and compared with experimental data. Content Type Journal Article Pages - DOI 10.3233/JAE-141761 Authors F. Dughiero, Department of Industrial Engineering, University of Padova, Padova, Italy M. Forzan, Department of Industrial Engineering, University of Padova, Padova, Italy C. Pozza, Department of Industrial Engineering, University of Padova, Padova, Italy Pastore, Inova Lab s.r.l., Via Turazza, Padova, Italy M. Zerbetto, Whirlpool R&D, Via A. Moro, Cassinetta di Biandronno, Italy Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: A comparison between a classical parametric NSGA (Non-dominated Sorting Genetic Algorithm) and a non-parametric NSKA (Non domination Sorting Kinetic Algorithm) optimization method is proposed on a benchmark problem of inverse induction heating characterized by two conflicting objectives. Content Type Journal Article Pages - DOI 10.3233/JAE-141759 Authors P. Di Barba, Department of Industrial and Information Engineering, University of Pavia, Pavia, Italy F. Dughiero, Department of Industrial Engineering, University of Padova, Padova, Italy M. Forzan, Department of Industrial Engineering, University of Padova, Padova, Italy E. Sieni, Department of Industrial Engineering, University of Padova, Padova, Italy Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Fractional dual solutions to the Maxwell equations for a dielectric slab placed in an unbounded dielectric magnetic medium are determined using the fractional curl operator. For extreme values of the intrinsic impedance of the host dielectric magnetic medium, the geometry becomes equivalent to that of a PEC or a PMC waveguide. In this way, the fractional dual fields for the PEC and PMC waveguide are also easily obtained. Content Type Journal Article Pages - DOI 10.3233/JAE-141742 Authors Samina Gulistan, Department of Electronics, Quaid-i-Azam University, Islamabad, Pakistan M. Abbas, Department of Electronics, Quaid-i-Azam University, Islamabad, Pakistan A.A. Syed, Department of Electronics, Quaid-i-Azam University, Islamabad, Pakistan Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Content Type Journal Article Category Preface Pages - DOI 10.3233/JAE-141751 Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: This paper attempts to present a novel development of an electromagnetic non-contact surface velocity measurement technique in electrically conducting liquids which could be applied in high-temperature metallurgical processes involving metal melts. The technique is based on Lorentz force velocimetry, i.e. on measuring the force which is generated by the interactions of the melt flow and an externally applied magnetic field that is spanned by permanent magnet system. The electromagnetically induced force pushes the magnet system into the direction of the flow and can be measured using a force sensor that is attached to the magnet system. As the measured force linearly depends on melt velocity, a non-contact evaluation of the velocity can be achieved. However, the recorded force also depends on the electrical conductivity of the melt. In application this material property is a priori unknown as it strongly depends on both temperature and composition of the melt. Hence, calibration of such a measuring device becomes a cumbersome task. Our development aims to circumvent this deficit by applying a time-of-flight technique. According to this principle we design and test a prototype of sensor for measuring free-surface velocity. In the model experiments we use both solid bodies and the liquid metal GaInSn as test liquids. Content Type Journal Article Pages - DOI 10.3233/JAE-141758 Authors D. Schumacher, Institute of Thermodynamics and Fluid Mechanics, Technische Universität Ilmenau, Ilmenau, Germany Ch. Karcher, Institute of Thermodynamics and Fluid Mechanics, Technische Universität Ilmenau, Ilmenau, Germany Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Nano-sized superparamagnetic Y_{3}Fe_{5}O_{12} ferrite having a high heat generation ability in an AC magnetic field was prepared by physical bead milling. The highest heat ability in the AC magnetic field was for the fine Y_{3}Fe_{5}O_{12} powder with a 16-nm crystallite size (the samples were milled for 4 h using 0.1 mmϕ beads). The main reason for the high heat generation property of the milled samples was ascribed to an increase in the Néel relaxation of the superparamagnetic material. For the samples milled for 4 h using 0.1 mmϕ beads, the heat generation ability (W·g^{-1}) was estimated using a 3.58 × 10^{-4} · f· H^{2} frequency (f/kHz) and the magnetic field (H/kA·m^{-1}), which is the highest reported value of superparamagnetic materials. Furthermore, Y_{3}Fe_{5}O_{12} microspheres having a 20–32 μm diameter range were prepared by a spray dryer using the bead-milled nano-sized particles. Content Type Journal Article Pages - DOI 10.3233/JAE-141763 Authors Hiromichi Aono, Graduate School of Science and Engineering, Ehime University, Matsuyama, Japan Takashi Naohara, Graduate School of Science and Engineering, Ehime University, Matsuyama, Japan Tsunehiro Maehara, Graduate School of Science and Engineering, Ehime University, Matsuyama, Japan Hideyuki Hirazawa, Department of Environmental Materials Engineering, Niihama National College of Technology, Niihama, Japan Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Dual frequency AC magnetic field effects are analyzed in the case of levitated samples heated, melted and confined. The time dependent numerical models based on accurate spectral approximation give an insight to oscillation patterns and stability conditions for a copper sample both in solid and liquid state after the melting stage. Application to microgravity experiments planned at International Space Station and the full gravity magnetic levitation for the similar sample are presented. Content Type Journal Article Pages - DOI 10.3233/JAE-141754 Authors V. Bojarevics, University of Greenwich, Park Row, London, UK K. Pericleous, University of Greenwich, Park Row, London, UK Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Dual frequency induction hardening can be a low distortion alternative to case hardening for gearings. However, profound process understanding is still lacking, which is reflected by the absence of appropriate models allowing the prediction of final component properties in terms of residual stresses and distortion. In order to close this gap, a 2-D numerical model has been developed, considering short time austenitization kinetics of quenched and tempered AISI 4140. The induction heating model considering the nonlinear magnetic material behaviour is realized with MSC.Marc®, whereas the mechanical response is implemented in Abaqus/Standard®. The comparison of residual stresses and distortion with experimental results shows that the developed model is in good agreement. Numerical investigations have shown that the core temperature and the TRIP strain during the martensitic transformation will determine the quantitative distribution of the residual stresses. Content Type Journal Article Pages - DOI 10.3233/JAE-141752 Authors M. Schwenk, Institute of Applied Materials – WK, Karlsruhe Institute of Technology, Karlsruhe, Germany J. Hoffmeister, Institute of Applied Materials – WK, Karlsruhe Institute of Technology, Karlsruhe, Germany V. Schulze, Institute of Applied Materials – WK, Karlsruhe Institute of Technology, Karlsruhe, Germany Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: A great deal of work with respect to both physical and numerical modelling of Czochralski crystal growth has been conducted in the generic Rayleigh-Bénard system. In order to come closer to the conditions in a real Czochralski puller, specific effects such as the influence of a rounded crucible bottom, deviations of the thermal boundary conditions from the generic case, crucible and/or crystal rotation, and the influence of magnetic fields are often studied separately. Within this paper we present a model experiment focusing on investigations of the impact of magnetic fields on the flow in a Czochralski puller. To achieve similar thermal boundary conditions as in an industrial growth facility, a double-walled rounded bottom glass crucible was chosen to hold the fluid. Similarity of the heat transfer conditions was guaranteed by selecting the ternary alloy GaInSn as the model fluid. Measurements of the fluid flow have been conducted by means of the ultrasound Doppler velocimetry. The results reveal the complex flow structure of natural convection in a Czochralski crucible. Because the growth of high quality mono-crystalline crystals is impeded by such a non-axisymmetric flow, rotating magnetic fields (RMF) are often proposed to render the flow more axisymmetric. To study the effect of an RMF on the natural convection in a Czochralski system the experimental apparatus was mounted inside the home-made MULTIpurpose MAGnetic field facility (MULTIMAG). In the present contribution the three-dimensional convective patterns as well as the resulting temperature fluctuations will be discussed both for the pure buoyant case and for the application of an RMF. Content Type Journal Article Pages - DOI 10.3233/JAE-141756 Authors J. Pal, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany A. Cramer, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany G. Gerbeth, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: It is generally accepted that not all cyclic stresses below the fatigue limit are non-damaging. Particularly in spectrum loading, the inclusion of some cyclic stresses below the fatigue limit can reduce the fatigue life of a component. It is believed that the boundary between damaging and non-damaging stresses is the so-called micro-plastic limit (MPL) defined as a macro-stress at which dislocation pile-up stresses begin to obstruct the magnetic domains in rotation to the direction of the tensile stress. This paper shows that MPL can be determined from changes in magnetic permeability during tensile loading. In our work, changes in magnetic permeability were measured indirectly – by measuring changes in electrical impedance (a.c. resistance and inductance). Measurements were performed on normalized low-C steel CSN 411375, and the microplastic limit was determined by evaluating the ΔR – σ and ΔL – σ records. Content Type Journal Article Pages - DOI 10.3233/JAE-141743 Authors L'ubomír Gajdoš, Institute of Theoretical and Applied Mechanics, Academy of Sciences of the Czech Republic, Prosecká, The Czech Republic Martin Šperl, Institute of Theoretical and Applied Mechanics, Academy of Sciences of the Czech Republic, Prosecká, The Czech Republic Jaroslav Kaiser, Faculty of Mechanical Engineering, University of West Bohemia, Univerzitní, Pilsen, The Czech Republic Václav Mentl, Faculty of Mechanical Engineering, University of West Bohemia, Univerzitní, Pilsen, The Czech Republic Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: The closing process of intelligent AC contactor can be affected by selection phase angle and the dynamic control strategy. A control strategy is proposed to compensate the influence of closing process at different phase angles. The mathematical model of the closing process is established by analyzing the dynamic characteristics of the contactor. Simulation and experimental comparisons show that the proposed model can predict the dynamic response of the closing process effectively. The relationship between the closing phase angle and the end speed is analyzed by using the experimental measurements. The selection phase angle and dynamic control is implemented by combining voltage zero crossing and PWM section control technology. The input voltage and the zero-crossing signal are taken as the control input while the PWM duty cycles and the strong excitation time are taken as the control output. The control strategy is implemented by using the lookup table. Experimental results show that by using the proposed strategy, the contactors can be closed with the same phase angle. Therefore the consistency of the dynamic closing process of the intelligent contactors can be guaranteed. Also, the movable armature end speed of the closing is reduced 31.5% and the closing time is decreased 15.6%. The mechanical life of the contactor has been increased about 4 times in the durability test. Content Type Journal Article Pages - DOI 10.3233/JAE-141741 Authors Peng Ye, The Key Laboratory of Low-Voltage Apparatus Intellectual Technology of Zhejiang, Wenzhou University, Wenzhou, Zhejiang, China Liang Shu, The Key Laboratory of Low-Voltage Apparatus Intellectual Technology of Zhejiang, Wenzhou University, Wenzhou, Zhejiang, China Guichu Wu, The Key Laboratory of Low-Voltage Apparatus Intellectual Technology of Zhejiang, Wenzhou University, Wenzhou, Zhejiang, China Liang Zhou, The Key Laboratory of Low-Voltage Apparatus Intellectual Technology of Zhejiang, Wenzhou University, Wenzhou, Zhejiang, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: The paper describes the alternative designs and performance of a single-phase permanent magnet linear moving-magnet linear oscillating actuators (LOA) which has been developed for orbital friction welding. The influences of the pole ratio on the performance of the LOAs are investigated and the optimal parameters have been identified with reference to the thrust force characteristics. It can be illustrated that a quasi-Halbach magnetized LOA, in which the magnets are assembled on a nonmagnetic mover yoke, represents the best electromagnetic performances. Finally, the predicted thrust force-current characteristic of quasi-Halbach magnetized LOA is validated by measurements on a prototype actuator. Content Type Journal Article Pages - DOI 10.3233/JAE-141880 Authors Fei Xu, Department of Electrical Engineering, Harbin Institute of Technology, Harbin, Heilongjiang, China Jianhui Hu, Department of Electrical Engineering, Harbin Institute of Technology, Harbin, Heilongjiang, China Jibin Zou, Department of Electrical Engineering, Harbin Institute of Technology, Harbin, Heilongjiang, China Yong Li, Department of Electrical Engineering, Harbin Institute of Technology, Harbin, Heilongjiang, China Yongxiang Xu, Department of Electrical Engineering, Harbin Institute of Technology, Harbin, Heilongjiang, China Hua Fan, Department of Electrical Engineering, Harbin Institute of Technology, Harbin, Heilongjiang, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: This paper presents a new eddy current modeling approach in which the edge field contribution for a finite width conducting plate is accounted for. The 3-D steady-state analytic eddy current model accounts for the source field contributions from oscillatory as well as heave and translational velocity motional effects. The paper discusses the modeling inaccuracies caused by neglecting the source field contributions on the edges of the conductive plate. The new modeling approach is validated by comparing the analytic calculations with a 3-D steady-state finite element analysis model. Content Type Journal Article Pages - DOI 10.3233/JAE-141874 Authors Subhra Paul, Laboratory for Electromechanical Energy Conversion and Control, Electrical and Computer Engineering, University of North Carolina at Charlotte, Charlotte, NC, USA Jonathan Z. Bird, Laboratory for Electromechanical Energy Conversion and Control, Electrical and Computer Engineering, University of North Carolina at Charlotte, Charlotte, NC, USA Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: This work presents the development of a new approach to EMAT finite element method (FEM) simulations by using a novel coupled electromagnetic-mechanical equation system. Validation is performed within the limits of the un-coupled equations using commercially available FEM codes. The advantages and drawbacks of the new method versus the traditional un-coupled approach are evaluated for various EMAT patterns. Numerical FEM analyses use a sparse direct solver with either Euler or Crank-Nicolson implicit time integration methods. Content Type Journal Article Pages - DOI 10.3233/JAE-141875 Authors Daniel Garcia-Rodriguez, Japan Atomic Energy Agency, Fast Breeder Reactor Safety Center, Tsuruga-shi, Fukui-ken, Japan Ovidiu Mihalache, Japan Atomic Energy Agency, Fast Breeder Reactor Safety Center, Tsuruga-shi, Fukui-ken, Japan Masashi Ueda, Japan Atomic Energy Agency, Fast Breeder Reactor Safety Center, Tsuruga-shi, Fukui-ken, Japan Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Lorentz force eddy current testing is a novel nondestructive testing technique which can be applied preferably to the identification of internal defects in non-ferromagnetic moving conductors. This paper describes the comparison of these new technique with well-known eddy current testing. Measurements and numerical simulations have been done for both techniques for artificial subsurface defects in a test specimen made of Aluminum alloy moving with constant velocity. Content Type Journal Article Pages - DOI 10.3233/JAE-141872 Authors Matthias Carlstedt, Department of Advanced Electromagnetics, Technische Universität Ilmenau, Helmholtzplatz, Ilmenau, Germany Konstantin Porzig, Department of Advanced Electromagnetics, Technische Universität Ilmenau, Helmholtzplatz, Ilmenau, Germany Robert P. Uhlig, Department of Advanced Electromagnetics, Technische Universität Ilmenau, Helmholtzplatz, Ilmenau, Germany Mladen Zec, Department of Advanced Electromagnetics, Technische Universität Ilmenau, Helmholtzplatz, Ilmenau, Germany Marek Ziolkowski, Department of Advanced Electromagnetics, Technische Universität Ilmenau, Helmholtzplatz, Ilmenau, Germany Hartmut Brauer, Department of Advanced Electromagnetics, Technische Universität Ilmenau, Helmholtzplatz, Ilmenau, Germany Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: The electrical impedance tomography is a widely investigated problem with many applications in physical and biological sciences. A new nondestructive method of the flood embankment dampness was tested. The basic information about the built measuring system, including the prototype equipment is given. The setup was used to determine the dampness of the test flood blank on a specially built model. The forward problem solution (in the electrical impedance tomography) is solved by the determining potential distribution inside the region under given boundary conditions. The full information about region is considered, This problem is solved by Laplace's equation. The level set methods with the Chan-Vese model were applied in the inverse problem for the image reconstruction. Content Type Journal Article Pages - DOI 10.3233/JAE-141868 Authors Tomasz Rymarczyk, NET-ART, Lotnicza 3, 20-322, Lublin, Poland. E-mail: tomasz@rymarczyk.com Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: In order to meet the engineering requirement of gas pipeline inline inspection for cracking defects, a new ultrasonic guided wave (GW) method based on electromagnetic acoustic transducer (EMAT) has emerged. In consideration of the large amount of original inspection data and the limited capacity of the storing device, the research on rapid and large ratio data compression is needed. This paper proposes a new large ratio data compression method based on subsection adaptive method (SAM) and wavelet neural network (WNN) algorithm. The influences of parameter selection on the compression quality, speed and ratio and the method of enhancing the compression speed of this method is studied. The experiment results indicate that compared with the traditional WWN compression algorithm, the proposed method has higher compression quality and speed, and a large compression ratio of 110:1 is achieved by the proposed method. It is thus suitable for gas pipeline crack inline inspection based on EMAT-generated GW. Content Type Journal Article Pages - DOI 10.3233/JAE-141871 Authors Zheng Wei, State Key Lab of Power Systems, Department of Electrical Engineering, Tsinghua University, Beijing, China Songling Huang, State Key Lab of Power Systems, Department of Electrical Engineering, Tsinghua University, Beijing, China Wei Zhao, State Key Lab of Power Systems, Department of Electrical Engineering, Tsinghua University, Beijing, China Shen Wang, State Key Lab of Power Systems, Department of Electrical Engineering, Tsinghua University, Beijing, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: A measuring system is presented to improve the volumetric strain measurement in hydrostatic pressure environment for a hydro-compression loading test. The measuring system consists of a new triaxial extensometer, a novel contactless signal transmission system and an IPT (inductive power transfer) equipment. By the extensometer, triaxial deformations of foam specimen can be measured directly, from which the volumetric strain is determined. Sensitivities of the triaxial extensometer are predicted using a simplified analytical model, and verified through experimental calibrations. To avoid the punching and lead sealing techniques on the pressure chamber for hydro-compression loading and transfer the strain data of the triaxial extensometer effectively, a new modus of contactless differential signaling is developed in this paper for elimination of noise caused by the IPT. Content Type Journal Article Pages - DOI 10.3233/JAE-141876 Authors Zijian Jing, State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi'an Jiaotong University, Xi'an, Shaanxi, China Minglong Xu, State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi'an Jiaotong University, Xi'an, Shaanxi, China Bo Feng, State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi'an Jiaotong University, Xi'an, Shaanxi, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Different phases which exist in a duplex stainless steel (DSS) affect mechanical as well as electromagnetic properties. Therefore, an eddy current (EC) technique can be utilized to detect phases inclusions. In order to evaluate and identify the amount of deleterious phases it is important to assess the impact of electromagnetic properties of material on a measuring signal. This paper presents a study on the influence of DSS properties changes caused by a sigma (σ) phase on signal measured by an EC transducer. The results of an analytical and numerical analysis are presented. The analytical modeling allows to identify the electromagnetic properties and evaluate the amount of σ phase in the tested material. Content Type Journal Article Category 1 Pages - DOI 10.3233/JAE-141873 Authors Grzegorz Psuj, Department of Electrical and Computer Engineering, Faculty of Electrical Engineering, West Pomeranian University of Technology, Szczecin, Poland Tomasz Chady, Department of Electrical and Computer Engineering, Faculty of Electrical Engineering, West Pomeranian University of Technology, Szczecin, Poland Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Since the excitement of gecko free-walk on a smooth surface is discovered with the cause of Wan der Waals force, researchers have focused on the development of biomimetic gecko tape. Hierarchical structure and anisotropic adhesion are two of the spotlights. However, little work has been done on integration of these two parameters. This paper presents a model design of orientated micro-and nano-arrays including three levels of setae, branches and spatulae. Finite element method is applied for compression shear test simulation. The anisotropic property is controllable due to the hierarchical surface design. Content Type Journal Article Pages - DOI 10.3233/JAE-141867 Authors Daniel Su, State Key Laboratory of Mechanical System and Vibration, Institute of Biomedical Manufacturing and Life Quality Engineering, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai, China Xiang Li, State Key Laboratory of Mechanical System and Vibration, Institute of Biomedical Manufacturing and Life Quality Engineering, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai, China Yun Luo, State Key Laboratory of Mechanical System and Vibration, Institute of Biomedical Manufacturing and Life Quality Engineering, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: This paper proposes an inversion procedure, based on radial wavelet basis function (RWBF) neural network, to reconstruct 3-D defect profiles from magnetic flux leakage (MFL) data. The architecture of the neural network, the adaptive training algorithm and the reconstruction process are presented. Defects reconstructed from both simulated and experimental MFL data, together with comparison with two other inversion methods, demonstrate the efficiency and accuracy of the proposed inversion procedure. Content Type Journal Article Pages - DOI 10.3233/JAE-141865 Authors Junjie Chen, State Key Laboratory of Power System and Department of Electrical Engineering, Tsinghua University, Beijing, China Songling Huang, State Key Laboratory of Power System and Department of Electrical Engineering, Tsinghua University, Beijing, China Wei Zhao, State Key Laboratory of Power System and Department of Electrical Engineering, Tsinghua University, Beijing, China Shen Wang, State Key Laboratory of Power System and Department of Electrical Engineering, Tsinghua University, Beijing, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Recently, permanent magnetic actuator (P.M.A.) is widely used to drive the mechanism of vacuum circuit breaker (V.C.B.). This paper deals with the optimal design of P.M.A. for V.C.B. using the response surface method (R.S.M.). First, the dynamic characteristics of the initial P.M.A. model, such as the holding force, exciting current, and action complete time, are calculated by coupled electrical-mechanical problem based on finite element method (F.E.M.). In order to verify the validity of numerical results obtained from finite element analysis (F.E.A.), the calculated dynamic characteristics of the initial P.M.A. model are compared with no-load test results. Next, using the R.S.M., the initial P.M.A. model is optimized to improve the dynamic characteristics. Finally, in order to verify the validity of the P.M.A. model optimized by using the R.S.M., the dynamic characteristics of the optimized P.M.A. model are calculated by using F.E.A. and compared with those of the initial P.M.A. model. Content Type Journal Article Pages - DOI 10.3233/JAE-141870 Authors Hyun-Mo Ahn, Department of Electrical Engineering, Dong-A University, Busan, Korea Jong-Deok Lee, Department of Electrical Engineering, Dong-A University, Busan, Korea Kug-Nam Park, EV Power Control Solution Team, LS Industrial Systems Co., Ltd., Cheongju, Korea Yeon-Ho Oh, Power Apparatus Research Center, Korea Electrotechnology Research Institute, Changwon, Korea Sung-Chin Hahn, Department of Electrical Engineering, Dong-A University, Busan, Korea Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Their small size together with a remarkable field sensitivity are the most prominent features of present-day GMR sensors paving the way for various applications in automated non-destructive testing (NDT). This work presents a prototype for fast and automated magnetic testing of roller bearings. A local magnetization unit excites the magnetic field inside the bearing. As a result of a design study and the following wafer fabrication the probe was equipped with NDT-adapted GMR sensor arrays in which 48 elements measures the field response. The detection of artificial and 40 μm deep defects could be resolved with a SNR better than 20 dB. In addition, we report of first results of a POD (Probability of Detection) analysis using GMR sensors to investigate bearings with EDM (electronic discharge machining) notches having depths down to 10 μm. Finally, we estimate successfully the depth of a 57 μm notch from the measured data. Content Type Journal Article Pages - DOI 10.3233/JAE-141866 Authors Matthias Pelkner, BAM Federal Institute for Material Research and Testing, Berlin, Germany Verena Reimund, BAM Federal Institute for Material Research and Testing, Berlin, Germany Thomas Erthner, BAM Federal Institute for Material Research and Testing, Berlin, Germany Marc Kreutzbruck, BAM Federal Institute for Material Research and Testing, Berlin, Germany Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: To calculate the complex permeability of soft magnetic composites, two-dimensional analytical models with and without the defects were used for the complex case. The relation of the complex permeability with the frequency, component size ratio δ and inclusion particle size is deduced. The results show that the effect of the defects is even more pronounced for the complex permeability. The complex permeability is a function of the component size ratio δ and the size of the inclusion. Increasing the component size ratio δ causes a decrease of the complex permeability at the same frequency. With the increase of inclusion particle size when the component size ratio keeps constant 0.01, both of the real and imaginary parts increase. In addition, the theoretical method is tested by the experimental results, which can be used to design parameters before the experiment. Content Type Journal Article Pages - DOI 10.3233/JAE-141861 Authors Ling Xiao, State Key Laboratory for Strength and Vibration of Mechanical Structures, Xi'an Jiaotong University, Xi'an, Shaanxi, China Yanhua Sun, State Key Laboratory for Strength and Vibration of Mechanical Structures, Xi'an Jiaotong University, Xi'an, Shaanxi, China Chunhua Ding, State Key Laboratory for Strength and Vibration of Mechanical Structures, Xi'an Jiaotong University, Xi'an, Shaanxi, China Lihua Yang, State Key Laboratory for Strength and Vibration of Mechanical Structures, Xi'an Jiaotong University, Xi'an, Shaanxi, China Wenjie Cheng, State Key Laboratory for Strength and Vibration of Mechanical Structures, Xi'an Jiaotong University, Xi'an, Shaanxi, China Lie Yu, State Key Laboratory for Strength and Vibration of Mechanical Structures, Xi'an Jiaotong University, Xi'an, Shaanxi, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Electrical error which contains amplitude error, function error and zero error has a direct impact on accuracy of resolver when resolver is used as a angle measuring device in control system. Harmonic interference existing in the output electromotive force (EMF) of signal windings is the main influencing factor of function error. Therefore, the reduction of harmonic interference will greatly weaken function error. In this paper, an axial flux variable-reluctance (AFVR) resolver with short pitch distributed winding is put forward on the basis of former variable-reluctance resolver. By the analyses of finite element method (FEM), high order harmonic of output EMF makes the distortion of EMF waveform and causes errors. Furthermore, the change regulation of high harmonics in the output EMF is got. The optimization analysis is done to rotor shape, pole-pairs and each group teeth number of this new resolver. Through FEM analysis and discussion on the optimized AFVR resolver, the analytic results show that the influence of harmonic interference is seriously weakened, and measurement accuracy is upgraded. Content Type Journal Article Pages - DOI 10.3233/JAE-141862 Authors Hao Wang, Department of Electrical Engineering, Harbin Institute of Technology, Harbin, Heilongjiang, China Jing Shang, Department of Electrical Engineering, Harbin Institute of Technology, Harbin, Heilongjiang, China Yong Li, Department of Electrical Engineering, Harbin Institute of Technology, Harbin, Heilongjiang, China Yongxiang Xu, Department of Electrical Engineering, Harbin Institute of Technology, Harbin, Heilongjiang, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Companies of power transmission lines and telecommunications need to know the condition of their structures. However, there are ones which are buried or encased in concrete below-ground. Nondestructive techniques are essentials to investigate the condition of the rods used to anchor guy cables in guyed towers. A connector and a matching circuit have been designed to allow a network analyzer to apply and receive high frequency signals on these rods and, furthermore, to be able to identify corrosion or holes on an anchor rod using a promising nondestructive technique. High frequency analysis have been done on the results provided by simulations and experimental tests through the reflected signals that come in the input port of the connector and matching circuit. The high frequency connector, named CHAAF, was fabricated and tested. Content Type Journal Article Pages - DOI 10.3233/JAE-141864 Authors L.R.G.S.L. Novo, Department of Electronics and Systems, Federal University of Pernambuco, Recife, Brazil M.T. De Melo, Department of Electronics and Systems, Federal University of Pernambuco, Recife, Brazil M.R.T. De Oliveira, Department of Electronics and Systems, Federal University of Pernambuco, Recife, Brazil J.M.B. Bezerra, Department of Electrical Engineering and Power Systems, Federal University of Pernambuco, Recife, Brazil L.H.A. De Medeiros, Department of Electrical Engineering and Power Systems, Federal University of Pernambuco, Recife, Brazil R.R.B. Aquino, Department of Electrical Engineering and Power Systems, Federal University of Pernambuco, Recife, Brazil Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: This paper discusses high frequency acoustic noise generated by an IH cooker. Mechanism of the high frequency acoustic noise generation is clarified by experimental study. Recently, influence of the electromagnetic wave on the human body is worried. They symptoms some users of home electronic appliances feel are headache and nausea. There is a report that other users who are using IH cooking heater also feel these symptoms. We have discovered that the high frequency acoustic noise, which is generated from an IH cooker, indicates strong-level sound pressure. High frequency strong acoustic noise must not be ignored, because its danger on our health is reported scientifically and medical standpoints. Then, it becomes necessary to examine the suppressing method of high frequency acoustic noise. In this paper, generating mechanism of the high frequency (20 kHz ∼) acoustic noise is clarified by the experiments. Content Type Journal Article Pages - DOI 10.3233/JAE-141863 Authors Hironobu Yonemori, Department of Mechanical and Electronic Engineering, Salesian Polytechnic, Machida-city, Tokyo, Japan Akihiro Fujiwara, Department of Mechanical and Electronic Engineering, Salesian Polytechnic, Machida-city, Tokyo, Japan Ryo Maruyama, Department of Mechanical and Electronic Engineering, Salesian Polytechnic, Machida-city, Tokyo, Japan Miki Kobayashi, Electrical and Electronics Engineering, Kogakuin University Graduate School, Shinjuku-ku, Tokyo, Japan Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Viscous, magnetization and damping properties of magnetic compound fluids containing fibrous material such as alpha-cellulose were investigated experimentally. It is shown that adding fibrous material to magnetic functional fluids is effective on increasing viscosity on the fluid while the amplification ratio of damping force in the presence of magnetic field against damping force in the absence of magnetic field decrease with increase of volume fraction of the fibrous material. Content Type Journal Article Pages - DOI 10.3233/JAE-141857 Authors Yasushi Ido, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya, Japan Koichi Hayashi, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya, Japan Satoshi Ueno, Aisin AW Co. Ltd., Fujii-cho, Anjyo, Japan Takashi Todaka, Oita University, Dannoharu, Oita, Japan Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Multilayered Tubular Structures (MTS) such as pipeline are widely employed in such industrial fields as nuclear energy, petroleum, etc. It is vital to non-destructively evaluate MTS periodically before catastrophic accidents take place. As one of the advanced Electromagnetic Nondestructive Evaluation (ENDE) techniques, Pulsed Eddy Current Testing (PECT) has been found advantageous over the other ENDE methods regarding evaluation of integrity of MTS. In this paper, a fast forward model of PECT inspection of MTS is proposed based on the analytical modeling, namely the Extended Truncated Region Eigenfunction Expansion (ETREE). The closed-form expressions of PECT signals of 3D magnetic field and coil Electromotive Force (EMF) have been formulated. The proposed model has been verified by Finite Element Modeling (FEM) and experiments. The advantages of the model in terms of high computational speed and accuracy have been identified. Content Type Journal Article Pages - DOI 10.3233/JAE-141859 Authors Yong Li, Research Centre for Inspection and Evaluation of Nuclear Structural Integrity, State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi'an Jiaotong University, Xi'an, Shaanxi, China Xiangbiao Liu, Research Centre for Inspection and Evaluation of Nuclear Structural Integrity, State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi'an Jiaotong University, Xi'an, Shaanxi, China Zhenmao Chen, Research Centre for Inspection and Evaluation of Nuclear Structural Integrity, State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi'an Jiaotong University, Xi'an, Shaanxi, China Hongda Zhao, Research Centre for Inspection and Evaluation of Nuclear Structural Integrity, State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi'an Jiaotong University, Xi'an, Shaanxi, China Wenlu Cai, Research Centre for Inspection and Evaluation of Nuclear Structural Integrity, State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi'an Jiaotong University, Xi'an, Shaanxi, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Fast and accurate crack detection techniques are required for the eddy current non destructive testing, especially in the case where a large amount of environmental noise exists. This paper presents a robust inverse solution for accurate shape reconstruction of natural cracks. A robust formulation is employed to deal with the uncertainties caused by the noise in the eddy current testing signals. The proposed method is capable of producing more robust results than the conventional formulation in terms of the statistical analysis of the reconstruction tests. Content Type Journal Article Pages - DOI 10.3233/JAE-141860 Authors Min Li, Department of Electrical and Computer Engineering, McGill University, Montreal, QC, Canada David Lowther, Department of Electrical and Computer Engineering, McGill University, Montreal, QC, Canada Frederico Guimar\~{a}es, Department of Electrical Engineering, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: The recently developed macro fiber composite (MFC) actuators are widely used in a variety application due to their high performance, flexibility and durability when compared with the prior actuators. This paper aims to model and compute the effective electromechanical properties of MFC actuators using the finite element method (FEM) and verify the accuracy the model through the experimental test. The results indicate that the FEM results are in good agreement with the experimental data. It demonstrates that the finite element (FE) model is effective to predict the electro-elastic properties of MFC when the electric field is applied. Content Type Journal Article Pages - DOI 10.3233/JAE-141858 Authors Jianhua Zhao, State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi'an Jiaotong University, Xi'an, Shaanxi, China Xingbo Man, Department of Civil Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi, China Xiaomin Xue, Department of Civil Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi, China Qing Sun, Department of Civil Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi, China Ling Zhang, State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi'an Jiaotong University, Xi'an, Shaanxi, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: The electromagnetic shunt damping absorber (EMSDA) is developed based on electromagnetic shunt damping mechanism. The governing equation of planar vibration system equipped with the EMSDA is derived. An optimization method is presented to determine the main working parameters of EMSDA on the basis of the built theoretical model. The objective function minimizing the response variance of system under white noise excitation is formulated. The particle swarm optimization algorithm is employed in optimization. The simulated and experimental studies on vibration control by use of EMSDA are conducted. The results show that the electromagnetic shunt damping absorber can attenuate significantly the structural vibration. Content Type Journal Article Pages - DOI 10.3233/JAE-141856 Authors Shilin Xie, State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi'an Jiaotong University, Xi'an, Shaanxi, China Peichao Li, State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi'an Jiaotong University, Xi'an, Shaanxi, China Xinong Zhang, State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi'an Jiaotong University, Xi'an, Shaanxi, China Bo Yan, State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi'an Jiaotong University, Xi'an, Shaanxi, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Certain aircraft and military applications require high speed machines with low stack-length and the lowest possible weight. Hence, the accommodation of the highest bore diameter may seem the natural option. However, a rotor design with high diameter results in significant increase in mechanical stresses in the employed magnet retention. In a sleeved magnet retention mechanism, the sleeve thickness can be increased in order to accommodate the stresses. However, this will result is significant drop in air-gap flux-density and will not yield the high power density expected by the machine. This paper presents an analytical technique that combines the sleeve stress model and the air-gap flux density model to calculate the optimal rotor diameter to achieve the maximum power of the machine design for a minimum stack-length. The technique is applied to both a Carbon Fibre sleeve version and a metallic sleeve version. The analytical calculation of the stresses is validated with mechanical finite-element simulations. The machine design with the analytical calculations is validated with electromagnetic finite element simulations. The results confirm the rotor design strategy and the design technique. Content Type Journal Article Pages - DOI 10.3233/JAE-141750 Authors W.U. Nuwantha Fernando, School of Electrical and Computer Engineering, RMIT University, Melbourne VIC, Australia Christopher Gerada, School of Electrical and Electronic Engineering, University of Nottingham, Nottingham, UK Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Detailed analytical and experimental approaches were performed to calculating the ratio of the pull-in thrust to the input power of High Density Transverse Flux linear Stepper Motor (HDTFLSM) with considerations of the electrical time constant, the mechanical time constant and the friction. The analytical approach involves the use of Fourier series analysis to derive the equation for the pull-in thrust to input power ratio. The experimentation was performed under different load conditions until the motor come to the standstill value. A chopped voltage was applied to motor at different speeds and the obtained results were compared with those for normal voltage. Comparison between analytical and experimental results shows good agreement, for instance at 0.22 m/s the difference percentage on normal voltage and chopped voltage are 6.1% and 6.7%, respectively. The chopped voltage has higher ratio of the pull-in thrust to the input power compare to normal voltage so that the machine performance can be improvised to a greater extent. The maximum improvement percentage of 18.8% on pull-in thrust to input power ratio for motor with chopped voltage was obtained at 0.22 m/s. Content Type Journal Article Pages - DOI 10.3233/JAE-141749 Authors Mohammad Reza Zare, Department of Electrical and Electronic Engineering, University Putra Malaysia, Selangor, Malaysia Norhisam Misron, Department of Electrical and Electronic Engineering, University Putra Malaysia, Selangor, Malaysia Ishak Aris, Department of Electrical and Electronic Engineering, University Putra Malaysia, Selangor, Malaysia Hiroyuki Wakiwaka, Shinshu University, Nagano, Japan Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: The application of two techniques to reconstruct the shape of a two-dimensional periodic perfect conductor from mimic the measurement data is presented. A periodic conducting cylinder of unknown periodic length and shape scatters the incident wave in half-space and the scattered field is recorded outside. After an integral formulation, the microwave imaging is recast as a nonlinear optimization problem; a cost functional is defined by the norm of a difference between the measured scattered electric fields and the calculated scattered fields for an estimated shape of a conductor. Thus, the shape of conductor can be obtained by minimizing the cost function. In order to solve this inverse scattering problem, transverse magnetic (TM) waves are incident upon the objects and two techniques are employed to solve these problems. The first is based on an particle swarm optimization (PSO) and the second is a self-adaptive dynamic differential evolution (SADDE). Both techniques have been tested in the case of simulated mimic the measurement data contaminated by additive white Gaussian noise. Numerical results indicate that the SADDE algorithm is better than the PSO in reconstructed accuracy and convergence speed. Content Type Journal Article Pages - DOI 10.3233/JAE-141748 Authors Yu-Ting Cheng, Electrical Engineering Department, Tamkang University Tamsui, Taiwan Chien-Ching Chiu, Electrical Engineering Department, Tamkang University Tamsui, Taiwan Shuo-Peng Chang, Electrical Engineering Department, Tamkang University Tamsui, Taiwan Jung-Chin Hsu, Electrical Engineering Department, Tamkang University Tamsui, Taiwan Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: A hybrid radial magnetic bearing (HRMB) with permanent magnet creating bias flux is used to reduce the power consumption. Laminated cores are widely used in HRMB to reduce eddy currents. Nevertheless, when the frequencies of rotation and control currents are extremely high, eddy-current effects in laminated iron cores still have a significant influence on the behavior and performance of magnetic bearings. In order to predict performance and guide design of the HRMB system in high frequency, an analytical method based on equivalent circuit model whose parameters are frequency-dependent is used in this paper. The analytical results show that, the eddy currents induced due to rotor movement and dynamically changing control currents will result in considerable magnitude decrease and phase lag of bearing stiffness. Furthermore, the eddy current effect on HRMB can be reduced by increasing the air gap, decreasing the laminations thickness and decreasing the laminations conductivity. Finally, a prototype is designed and fabricated; the experimental results demonstrate the validity of the analysis. Content Type Journal Article Pages - DOI 10.3233/JAE-141746 Authors Yun Le, Science and Technology on Inertial Laboratory, Fundamental Science on Novel Inertial Instrument and Navigation System Technology Laboratory, Beihang University, Beijing, China Jiancheng Fang, Science and Technology on Inertial Laboratory, Fundamental Science on Novel Inertial Instrument and Navigation System Technology Laboratory, Beihang University, Beijing, China Bangcheng Han, Science and Technology on Inertial Laboratory, Fundamental Science on Novel Inertial Instrument and Navigation System Technology Laboratory, Beihang University, Beijing, China Yin Zhang, Science and Technology on Inertial Laboratory, Fundamental Science on Novel Inertial Instrument and Navigation System Technology Laboratory, Beihang University, Beijing, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: In this paper, a compact dual-band power divider embedded with defect microstrip with periodic loading (DMSWPL) slow-wave structure is presented. The occupied space is effectively reduced by about 66.89% compared to the conventional dual-band Wilkinson power divider. The structure of this power divider and the formulas used to determine the design parameters have been given. Experimental results show that all the features of a conventional Wilkinson power divider, such as an equal power split, impedance matching at all ports, and a good isolation between the two output ports can be fulfilled at GSM-band (880 MHz ∼ 960 MHz) and DCS-band (1710 MHz ∼ 1880 MHz) simultaneously. Content Type Journal Article Pages - DOI 10.3233/JAE-141747 Authors Chia-Mei Peng, Department of Electronic Engineering, Jinwen University of Science and Technology, New Taipei, Taiwan I.-Fong Chen, Department of Electronic Engineering, Jinwen University of Science and Technology, New Taipei, Taiwan I.-Tung Chou, Department of Electronic Engineering, Jinwen University of Science and Technology, New Taipei, Taiwan Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Efficiency and torque ripple are usually especially concerned during the working process of permanent magnet synchronous motor (PMSM). The loss and cogging torque generated during the working process of PMSM are analyzed. A low-speed surface-mounted PMSM used for direct-drive pumping unit is optimized. For increasing efficiency and reducing cogging torque, Taguchi's method is employed and height of stator yoke, width of stator tooth, thickness of permanent magnet, and air-gap length are selected as the variables. The orthogonal experiment is conducted with FEM. The mean of the results and the two-order interaction effects between the selected variables are analyzed, then the best optimization combination is determined by the analysis of variance. The results show that Taguchi's method is an efficient and effective approach, which is finally proved by the prototype test. Content Type Journal Article Pages - DOI 10.3233/JAE-141773 Authors Junguo Cui, College of Mechanical and Electronic Engineering, China University of Petroleum, Qingdao, Shandong, China Wensheng Xiao, College of Mechanical and Electronic Engineering, China University of Petroleum, Qingdao, Shandong, China Longhua Wang, College of Mechanical and Electronic Engineering, China University of Petroleum, Qingdao, Shandong, China Hao Feng, College of Mechanical and Electronic Engineering, China University of Petroleum, Qingdao, Shandong, China Jianbo Zhao, College of Mechanical and Electronic Engineering, China University of Petroleum, Qingdao, Shandong, China Hongyan Wang, College of Mechanical and Electronic Engineering, China University of Petroleum, Qingdao, Shandong, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Three-dimensional (3-D) numerical simulations have been carried out taking into account the magnetohydrodynamics (MHD) effect of the railgun plasma armature. The 3-D space-time conservation element and solution element (CE/SE) method is derived for solving the coupled Navier-Stokes equations and Maxwell equations. The results show that a steeper gradient of the magnetic field and pressure that appears along the direction of the rail can be observed. The temperature distribution is affected by the boundary conditions for the radiative heat flux, with the maximum temperature appearing in the center near the base of the projectile. Circulation patterns of velocity that are evident in both the rail-to-rail plane and the insulator-to-insulator plane result from the convection and unbalanced force between the Lorentz force and pressure gradient. The periodical variation of the temperature and acceleration is obvious until a new steady state is achieved. This model can efficiently evaluate the dynamics of the plasma motion, and provide a basis on understanding the much more complex physical phenomena. Content Type Journal Article Pages - DOI 10.3233/JAE-141772 Authors Fei Gong, National Key Laboratory of Transient Physics, Nanjing University of Science and Technology, Nanjing, Jiangsu, China Xin Li, Beijing Institute of Electronic System Engineering, Beijing, China Chun-Sheng Weng, National Key Laboratory of Transient Physics, Nanjing University of Science and Technology, Nanjing, Jiangsu, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: A novel design of low profile circularly polarized antenna with performances of high gain and broad bandwidths is presented in this paper. Through the method of connecting the radiating patch to the ground plane by the metal wall, the peak gain of the antenna can be achieved as high as 11.8 dBi. Furthermore, In order to improve the axial ratio (AR) and impedance bandwidths, broadband 90° phase-shifter is introduced as feeding network. Annular-ring structure acts as radiating patch instead of circular patch can further improve the AR bandwidths. The measured results show that the antenna possess an impedance (VSWR ⩽ 2) bandwidths of 23.3% ranging from 1.87 GHz to 2.36 GHz, and right-handed circular polarized (RHCP) axial ratio (AR ⩽ 3dB) bandwidths of 24.3% ranging from 1.84 GHz to 2.35 GHz relative to the center frequency of 2.1 GHz, which agree well with simulated results. Content Type Journal Article Pages - DOI 10.3233/JAE-141770 Authors Xi Li, Science and Technology on Antenna and Microwave Laboratory, Xidian University, Xi'an, Shaanxi, China Xian-Bao Zheng, Xi'an Electronic Engineering Research Institute, Xi'an, Shaanxi, China Lin Yang, Science and Technology on Antenna and Microwave Laboratory, Xidian University, Xi'an, Shaanxi, China Shi-Wei Wang, Science and Technology on Antenna and Microwave Laboratory, Xidian University, Xi'an, Shaanxi, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: In this paper we present a finite element model in frequency domain which computes the Lorentz force that drives an electromagnetic forming (EMF) process. The only input data required are the electrical parameters of the capacitor bank, the coil and the work piece. The main advantage of this approach is that it provides an explicit relation between the parameters of the EMF process and the frequency of the discharge, which is a key parameter in the design of an optimum EMF system. The method is computationally efficient because it only requires to solve time-harmonic Maxwell's equations for a few frequencies and it can be very useful for coil design and for testing modeling conditions on complex three-dimensional geometries. Content Type Journal Article Pages - DOI 10.3233/JAE-141766 Authors Ruben Otin, International Center for Numerical Methods in Engineering, CIMNE, Parque Mediterráneo de la Tecnología, PMT, Barcelona, Spain Roger Mendez, International Center for Numerical Methods in Engineering, CIMNE, Parque Mediterráneo de la Tecnología, PMT, Barcelona, Spain Oscar Fruitos, International Center for Numerical Methods in Engineering, CIMNE, Parque Mediterráneo de la Tecnología, PMT, Barcelona, Spain Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: The arc in MIAB welding process follow two paths of motion, one along the circumference and other comprising the zigzag motion when commuting between outer diameter and inner diameter. The moving arc dissipates necessary heat such that the butt ends reach solidification followed by forging. In this study, a pivotal attempt is made to investigate the temperature distribution during the movement of arc along and across the faying surfaces using finite element method. Content Type Journal Article Pages - DOI 10.3233/JAE-141768 Authors S. Arungalai Vendan, School of Electrical Engineering, VIT University, Vellore, India V. Thangadurai, Department of Manufacturing Engineering, Central Institute of Plastics Engineering and Technology, Chennai, India A. Vasudevan, Department of Manufacturing Engineering, Central Institute of Plastics Engineering and Technology, Chennai, India A. Senthil Kumar, Department of Mechanical Engineering, University College of Engineering, Panruti, India Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: This paper presents the design and analysis of electromagnetic field distribution and torque characteristics of a novel three degrees of freedom deflection type permanent magnet actuator based on 3D finite element method and comparison analysis. The spatial magnetic field model, torque calculation model and 3D finite element application are presented and developed. Based on the calculation results, some important structure parameters' effects on the electromagnetic field and torque characteristics are discussed in detail with improved design schemes. The results provide the primary theoretical guide for the configuration design, optimization and control research of three degrees of freedom deflection type actuators. Content Type Journal Article Pages - DOI 10.3233/JAE-141774 Authors Zheng Li, School of Electrical Engineering, Hebei University of Science and Technology, Shijiazhuang, Hebei, China Yue Zhang, School of Electrical Engineering, Hebei University of Science and Technology, Shijiazhuang, Hebei, China Xinxin Wang, School of Electrical Engineering, Hebei University of Science and Technology, Shijiazhuang, Hebei, China Caisheng Wang, College of Engineering, Wayne State University, Detroit, MI, USA Caihong Yan, School of Electrical Engineering, Hebei University of Science and Technology, Shijiazhuang, Hebei, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: This paper presents the design and evaluation of a novel permanent magnet (PM) energy harvesting system for scavenging electrical energy from ambient vibrations. A two-phase tubular linear PM vibration energy harvester consisting of a mover attached with permanent magnets and a slotted stator with built-in two-phase electromagnetic coils is proposed to convert vibrational kinetic energy into electrical energy. Aiming at maximizing the efficiency of vibration-to-electrical energy conversion under designated vibration and limited space requirement, a systematic research, including innovative device design, theoretical modelling and analysis, and finite element evaluation on the PM vibration energy harvester will be presented in this paper. In addition, the methodology of winding the two-phase coils in slotted stator is explicated in order to fully utilize the harvested electrical energy. A two-phase rectifier circuit is developed to convert the alternative voltage generated by the PM harvester into DC voltage that can be used directly by the external resistive load. Simulation results indicate that the proposed linear PM vibration energy harvesting system is able to generate about 100 watt DC electrical power under the vibration with the velocity of 0.4 m/s and the output electrical power is proportional to the levels of vibration excitations. Content Type Journal Article Pages - DOI 10.3233/JAE-141769 Authors Xuezheng Jiang, Centre for Built Infrastructure Research, Faculty of Engineering and Information Technology, University of Technology, Sydney, NSW, Australia Jiong Wang, School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu, China Yancheng Li, Centre for Built Infrastructure Research, Faculty of Engineering and Information Technology, University of Technology, Sydney, NSW, Australia Jianchun Li, Centre for Built Infrastructure Research, Faculty of Engineering and Information Technology, University of Technology, Sydney, NSW, Australia Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: A newly arisen technique named metal magnetic memory is deemed to have potentials in detecting early damage, whereas it is lack of systematic micro-mechanism research in early fatigue damage of ferromagnetic components. The microscopic fatigue experimental system including XH-500 metallograhpic microscope, DIG300 special digital camera and magnetic memory testing device, combined with the magnetic memory microscopic fatigue observation method is adopted, and the tension-tension fatigue experiment with specimens made of steel 45 are conducted. The evolution process of fatigue short-crack initiation and growth is observed dynamically from the microscopic scale, and the variation regularity of microscopic Vickers hardness during the fatigue procedure is also given. At the same time, the variation of the magnetic memory signal on the surface of the V-shaped notch with cyclic numbers is analyzed, and the magnetic signal curve distribution regularity corresponding to different crack lengths is investigated. The results show that the magnetic memory signals exhibit an abnormal nonlinear wave when the local plastic deformation or micro-damage occurs, providing a feasible detection method for early fatigue damage of ferromagnetic materials. Content Type Journal Article Pages - DOI 10.3233/JAE-141767 Authors Jiancheng Leng, School of Mechanical Science and Engineering, Northeast Petroleum University, Daqing, Heilongjiang, China Hui Zhang, School of Mechanical Science and Engineering, Northeast Petroleum University, Daqing, Heilongjiang, China Lihua Wang, Data Interpretation and Evaluation Center, No.1 Mud Logging Company, Daqing Drilling and Exploration Engineering Corporation, Daqing, Heilongjiang, China Xiujie Miao, Daqing Medical College, Daqing, Heilongjiang, China Haiyan Xing, School of Mechanical Science and Engineering, Northeast Petroleum University, Daqing, Heilongjiang, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Piezoelectric vibration energy harvester as an autonomous power source for various types of sensors, actuators and MEMS devices has been investigated over the last decade. Traditional MEMS-based PZT single beam vibration energy harvester has low voltage output (usually less than 1~V) which cause rectifier circuit to consume most of power or turn off in practical applications. In this paper, to improve the voltage output as well as ensure high power output of the MEMS-based PZT vibration energy harvester, a PZT beam array configuration is proposed. Based on Hamilton's principle and Euler-Bernoulli beam theory, mathematical model for the proposed vibration energy harvester is established, and then the model is verified through finite element model implemented by program ANSYS. Both mathematical model and ANSYS simulation show that the voltage output of the proposed vibration energy harvester is 5 times of the traditional vibration energy harvester and the mathematical model also show that the power output of the proposed vibration energy harvester is the same as the traditional vibration energy harvester. From the mathematical model, the voltage output of the proposed vibration energy harvester increase linearly with the total number of the beams. Content Type Journal Article Pages - DOI 10.3233/JAE-141775 Authors Licheng Deng, Microsystem Research Center, Chongqing University, Chongqing, China Zhiyu Wen, National Center for International Research of Micro/Nano-System and New Material Technology, Chongqing, China Xingqiang Zhao, National Key Laboratory of Fundamental Science of Micro/Nano-Device and System Technology, Chongqing, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: The mutual inductance between the transmitted and received coils is an important parameter in the inductively coupled wireless power transmission system. The relative position between the linked coils may be arbitrary according to the applications. In this paper the analytical calculation of the mutual inductance between two arbitrarily positioned rectangular filaments is proposed based on a more general expression of mutual inductance calculation of two arbitrarily positioned straight filaments than Grover's. The calculation results are validated by using the finite element simulation tools. The previous published approximation methods for square coils in the coaxial, lateral misalignment or angular misalignment situations are verified that they are accurate when the two coils' relative distances are large. Content Type Journal Article Pages - DOI 10.3233/JAE-141779 Authors Yuhua Cheng, Education Ministry Key Lab of RF Circuits and Systems, Hangzhou Dianzi University, Hangzhou, Zhejiang, China Yaming Shu, Education Ministry Key Lab of RF Circuits and Systems, Hangzhou Dianzi University, Hangzhou, Zhejiang, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: In this work, a model constructed with the adaptive neuro – fuzzy inference system (ANFIS) for estimating the resonant frequency of rectangular ring compact microstrip antennas (RRCMAs) in UHF band is proposed. A total of 108 RRCMAs having different parameters related to the antenna dimensions and dielectric substrate were simulated with the help of electromagnetic packaged software IE3D™ based on method of moment (MoM) to generate the data pool for training and test processes of the ANFIS model. While 96 RRCMAs were employed for training, the remainders were used for test the ANFIS model. The resonant frequencies were computed with the average percentage errors (APE) as 0.014% and 0.666% for training and test, respectively. The accuracy of proposed model was successfully demonstrated by comparing with the results of a method over the simulated data previously published in the literature. Further to inspect the validity of the ANFIS model, a RRCMA operating at 2.44 GHz was designed and fabricated for this work, and the accurate results concerning the resonant frequency were achieved. Content Type Journal Article Pages - DOI 10.3233/JAE-141784 Authors Ali Akdagli, Department of Electrical – Electronics Engineering, Faculty of Engineering, Mersin University, Yenisehir, Mersin, Turkey Abdurrahim Toktas, Department of Information Technologies, Mersin University, Yenisehir, Mersin, Turkey Mustafa Berkan Bicer, Department of Electrical – Electronics Engineering, Faculty of Engineering, Mersin University, Yenisehir, Mersin, Turkey Ahmet Kayabasi, Department of Electronics and Automation, Silifke – Tasucu Vocational School of Selcuk University, Silifke, Mersin, Turkey Deniz Ustun, Department of Software Engineering, Faculty of Tarsus Technology, Mersin University, Tarsus, Mersin, Turkey Kasim Kurt, Department of Physics, Science and Letter Faculty, Mersin University, Yenisehir, Mersin, Turkey Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Electrical steel sheet that is used as a core in electrical machines deteriorates due to residual stress and external stress. The magnetic properties and stress need to be clarified in order to effectively utilize electrical steel sheet in electrical machines. We have measured the residual stress distribution in a motor core using an X-ray stress measurement device and clarified not only the tensile and compressive stress distributions, but also the shear stress distribution. In this study, a new measurement system is developed for determining vector magnetic properties under shear stress. The vector magnetic properties of the non-oriented electrical steel sheets under the alternating magnetic flux and rotating magnetic flux conditions were measured with the developed system. As the result, it was clear that the magnitude of the magnetic field strength vector and the magnetic power loss along the direction of about 135° increased by applying the shear stress. Content Type Journal Article Pages - DOI 10.3233/JAE-141799 Authors Yuichiro Kai, Faculty of Engineering, Oita University, Dannoharu, Oita Japan Masato Enokizono, Faculty of Engineering, Oita University, Dannoharu, Oita Japan Yukihito Kido, Oita Industrial Research Institute, Takaenishi, Oita, Japan Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Domain analyses of modern types of grain-oriented (GO) transformer steel are rare, and they are focussed on single grains under academic magnetization patterns. The present Kerr effect study reveals that grains of industrial, polycrystalline materials react in specific ways according to individual crystallographic orientations. The amount of parameters is very large, in special if additional flux components are given as a further impact. The paper reports a procedure for statistical evaluations of quasi-dynamic Kerr effect images. The instantaneous area ratios of bar domain portion BD, oblique domain portion OD and saturation S are determined with consideration of peak induction B_{RD} in the rolling direction (RD), axis ratio a of rotational magnetization, the angle ψ between B and RD, additional flux B_x in RD or B_z in normal direction. Focus is put on OD(t) which is assumed to be a key function for λ (t), i.e. the course of time of magnetostriction. As the most distinct tendencies, OD increases strongly with increases of a and ψ. OD(t) shows non-sinusoidal course of time with differences of the two halves of cycle. Rotation out of the RD yields sharp onsets of ODs, especially after half-cycle saturation. Additional off-plane flux enhances ODs in a general way. Content Type Journal Article Pages - DOI 10.3233/JAE-141804 Authors Viktor Galabov, EMCE, Vienna University of Technology, Gusshausstr, Vienna, Austria Helmut Pfützner, EMCE, Vienna University of Technology, Gusshausstr, Vienna, Austria Georgi Shilyashki, EMCE, Vienna University of Technology, Gusshausstr, Vienna, Austria Hiroi Yamaguchi, JFE Steel Corporation, Tokyo, Japan Yasuo Okazaki, Gifu University, Yanagido, Gifu, Japan Satoshi Arai, Gifu University, Yanagido, Gifu, Japan Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: The magnetic field distribution in and around thin ferromagnetic structures has been explored. Extrapolation and mathematical air flux compensation were used to obtain magnetic quantities on the sample surface and inside the sample, minimizing systematic errors for flux-metric and Gauss-metric measurements. A magneto elastic model was applied describing large deformations of thin ferromagnetic structures in a static magnetic field. The model based on global balance equations obeys the conservation of energy and momentum. Exemplified by the deformation of a soft-magnetic elastic plate in a uniform transverse magnetic field, the numerical evaluation of the model was compared to experimental results. Field distribution and deformation of the plate in a stepwise increased external field showed good agreement from small magnetization up to saturation. Content Type Journal Article Pages - DOI 10.3233/JAE-141803 Authors Elisabeth Leiss-Holzinger, RECENDT, Research Center for Non-Destructive Testing GmbH, Science Park 2/2.OG, Altenberger Straße 69, 4040 Linz, Austria. Tel.: +43(0)732/2468 4643; E-mail: elisabeth.leiss@recendt.at Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: We propose a model of an equivalent electrical circuit specifically designed for a ferrite inductor excited by a nonsinusoidal waveform valid for use in an electronic circuit simulator. We estimate the model parameters by means of Finite Elements in 2D which leads to significant computational advantages over the 3D model. We carry out the validation of the procedure for an RM14/I core by comparing the experimental and simulated output waveforms obtained at different frequencies and levels of excitation from the linear to the saturation regions. In addition, we consider the effect of power losses in the core. Content Type Journal Article Pages - DOI 10.3233/JAE-141802 Authors Rosa Ana Salas, Departamento de Tecnología Electrónica, Escuela Politécnica Superior, Universidad Carlos III de Madrid, Leganés (Madrid), Spain Jorge Pleite, Departamento de Tecnología Electrónica, Escuela Politécnica Superior, Universidad Carlos III de Madrid, Leganés (Madrid), Spain Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: In this paper influence of uniaxial stress loading on local changes of magnetic properties in a non-oriented silicon steel was examined. The measurements were carried out for different direction of loading force in respect to the rolling direction of the steel. Impact of the relationship between the rolling and the loading direction on evaluation of magnetic properties changes caused by stress was investigated using samples cut out at three different angles from the steel sheet. During the experiments two types of transducers with two and three sensitivity axes operating under rotating AC and static DC field were utilized. First, the observation of local changes of parameters related to a vector magnetic flux was carried out. Then algorithms of measured signals parameterization were utilized and evaluation of the stress distribution in tested samples was proceeded. Finally, the statistical analysis of computed signals parameters was applied and the correlation with stress-strain curve was assessed. Content Type Journal Article Pages - DOI 10.3233/JAE-141796 Authors Grzegorz Psuj, Department of Electrical and Computer Engineering, West Pomeranian University of Technology, Szczecin, Poland Tomasz Chady, Department of Electrical and Computer Engineering, West Pomeranian University of Technology, Szczecin, Poland Masato Enokizono, Faculty of Engineering, Oita University, Oita, Japan Takashi Todaka, Faculty of Engineering, Oita University, Oita, Japan Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Vector magnetic properties and two-dimensional magnetostrictions of electrical steel sheets under alternating and rotating magnetic flux conditions were measured. Based on the measured database, magnetic characteristic analyses of motor and transformer model cores have been carried out and distributions of two-dimensional magnetostriction have been estimated. The proposed method has been verified with a ring specimen in comparison of the analyzed result with the measured one. Content Type Journal Article Pages - DOI 10.3233/JAE-141794 Authors Daisuke Wakabayashi, Faculty of Engineering, Oita University, Dannoharu, Oita, Japan Takashi Todaka, Faculty of Engineering, Oita University, Dannoharu, Oita, Japan Masato Enokizono, Faculty of Engineering, Oita University, Dannoharu, Oita, Japan Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: This paper presents measured vector magnetic properties and two-dimensional magnetostriction of a non-oriented electrical steel sheet (including a 6.5% SiFe sheet), a grain-oriented electrical steel sheet, an Fe-based amorphous sheet, and a permendur sheet. These electrical steel sheets have been widely used as a core material of electrical equipment. Because it is difficult to reduce a building factor of a practical machine made of stress sensitive materials, it is therefore important to understand detailed magnetic properties and magnetostriction characteristics. In order to grasp the basic magnetic properties, vector magnetic properties and two-dimensional magnetostriction were measured in the alternating magnetic flux conditions in the arbitrary direction. In this paper, the relationship among the magnetic flux density vector, the magnetic field strength vector, and the two-dimensional magnetostriction in the various electrical steel sheets under alternating flux condition is clarified. Content Type Journal Article Pages - DOI 10.3233/JAE-141801 Authors Masayuki Yamagashira Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: We review state-of-the-art modeling of two-dimensional (2D) magnetization process in soft magnets. Emphasis is placed on the phenomenological assessment of the energy losses in steel sheets under rotational field. It is stressed that a general physically based theoretical framework, exploitable for applications in practical materials and machine cores, is not available at present. However, a rational approach to the 2D magnetic losses and their frequency dependence can be pursued. This is based on the separation between quasi-static (hysteresis) and dynamic magnetization processes and the connection with their unidirectional (scalar) counterpart. A number of vector models of the 2D quasi-static hysteresis behavior, typically residing on assessed scalar models, are discussed. They have prevalent formal-mathematical character, and, while being often helpful in numerical calculations, they leave unanswered the quest for solid physical interpretation. The dynamic magnetization process can, on the other hand, rely on a 2D phenomenological extension of the firmly established physical approach to the unidirectional scalar case provided by the statistical theory of losses. This is especially true for isotropic (i.e. nonoriented) magnetic laminations, where both rotational and elliptical flux loci can be conveniently handled. It permits one to achieve general appraisal of the experiments and flexible formulation, useful for numerical applications in machine cores. Content Type Journal Article Pages - DOI 10.3233/JAE-141798 Authors C. Appino, INRIM, Electromagnetics Division, Torino, Italy C. Ragusa, Politecnico di Torino, Dipartimento Energia, Torino, Italy F. Fiorillo, INRIM, Electromagnetics Division, Torino, Italy Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Magnetostriction, which refers to the deformation of the core material of transformers and electrical machines, is a main contributor to the total noise. In this work, a technique is proposed to calculate the magnetostrictive deformations of the core of the aforementioned devices. This technique is based on finite element approach with an artificial neural network model of the magnetostrictive behaviour of the core material. The strain measurements are carried out by using a dual heterodyne laser interferometer setup. The proposed technique is then applied to a single-phase test transformer core. As a validation, the vibration of the magnetised core of the same setup is measured by using a laser scanning vibrometer. Content Type Journal Article Pages - DOI 10.3233/JAE-141792 Authors Setareh Gorji Ghalamestani, Electrical Energy Laboratory, Department of Electrical Energy, Systems and Automation, Ghent University, Ghent, Belgium Lieven Vandevelde, Electrical Energy Laboratory, Department of Electrical Energy, Systems and Automation, Ghent University, Ghent, Belgium Joris J.J. Dirckx, Laboratory of Biomedical Physics, University of Antwerp, Antwerp, Belgium Patrick Guillaume, Acoustics and Vibration Research Group, Department of Mechanical Engineering, Free University of Brussels, Brussels, Belgium Jan A.A. Melkebeek, Electrical Energy Laboratory, Department of Electrical Energy, Systems and Automation, Ghent University, Ghent, Belgium Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: A study is carried out based on the evaluation of IEC-standard. Two measurement results on N.O. magnetic steel sheets, one from S-SST (Stress load type single sheet tester developed in our research laboratory), another is from SST based on the IEC standard regulation, are compared and discussed. As a result of the measurements, both magnetization curves coincide mostly, but magnetic power loss determined by IEC method is larger than that achieved by S-SST. The differences between them may be caused by magnetic field strength evaluation for each measurement method, magnetizing current method for IEC-type-SST and H-coil method for S-SST. The effective magnetic path is regulated in IEC but actually this may be variable according to the type of magnetic sheet, the structure of the SST and of applied magnetic field strength. In order to discuss this point, a virtual magnetic path length is introduced by using the applied magnetic field strength. Content Type Journal Article Pages - DOI 10.3233/JAE-141791 Authors Akifumi Kutsukake, Oita Industrial Reseach Institute, Takaenishi, Oita, Japan Yukihito Kido, Oita Industrial Reseach Institute, Takaenishi, Oita, Japan Tetsu Ikeda, Oita Industrial Reseach Institute, Takaenishi, Oita, Japan Tsugunori Kanada, Oita Prefectural Organization for Industry Creation, Higashikasuga, Oita, Japan Masato Enokizono, Oita University, Dannoharu, Oita, Japan Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: The research presented in this paper is motivated by the design of electrical devices submitted to mechanical stress. It aims at studying the magnetic behaviour of ferromagnetic materials submitted to biaxial stress. It deals with the evolution of the magnetic susceptibility, coercive field and magnetic losses with respect to stress, magnetic field level and frequency. These quantities are of primary importance in the design of rotors for high speed rotating machines. The work is focused on the magnetic behaviour of a standard grade of Iron-Silicon alloy under the form of thin sheet. Non conventional experiments are performed on cross-shaped samples in order to apply biaxial stress representative of the loadings experienced by rotors of rotating machines. These experiments are performed on a multiaxial testing machine, ASTREE. The magnetic loading is applied using a single U-yoke. The measurement of magnetic induction, magnetic field and strain is conducted by the means of needle-B sensor, H-coil sensors and Digital Image Correlation (DIC) respectively. Both anhysteretic and dissipative responses to magneto-mechanical loadings are considered. The results allow to identify the more critical stress configurations for this material. Content Type Journal Article Pages - DOI 10.3233/JAE-141793 Authors Mahmoud Rekik, LMT-Cachan, ENS Cachan, PRES Universud Paris, Cachan, France Olivier Hubert, LMT-Cachan, ENS Cachan, PRES Universud Paris, Cachan, France Laurent Daniel, LGEP, SUPELEC, CNRS, UPMC, Univ Paris-Sud, Gif sur Yvette, France Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: The efficiency of electrical machines depends among other things on the specific total loss of electrical steel the core is made of. Hence, a better understanding of the loss mechanism can improve the efficiency of machines. In order to analyze the specific total loss of electrical steel grades, they were separated into three components: the hysteresis loss component and both the classical and additional eddy current loss components. The relationship between loss components and direction of magnetization was analyzed. The aim of this paper is to provide a contribution to a better understanding of magnetic specific total loss in electrical steel sheets. Content Type Journal Article Pages - DOI 10.3233/JAE-141800 Authors Wojciech Pluta, Czestochowa University of Technology, Electrical Engineering Faculty, Al. Armii Krajowej 17, Czestochowa, 42-200, Poland. E-mail: plutaw@el.pcz.czest.pl Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Loss distributions of transformer cores are affected by z-flux effects if considered for the core surface. Here we propose the application of a thermal sensor which is inserted to the core interior through one of 16 channels of 2 mm width. Measurements were made on a 1-phase core assembled from laser-scribed SiFe. Throughout the core, the local building factor BF proved to increase towards the periphery which can be interpreted by interactions of highest anisotropy and non-linearity. Additional DC superposition yields non-uniform increases of BF at different core positions. Local losses tend to become more balanced – measurement locations with a priori high BF experience lower percentage increases, being more robust with respect to DC components. Content Type Journal Article Pages - DOI 10.3233/JAE-141797 Authors Franz Hofbauer, Institute of Electrodynamics, Microwave and Circuit Engineering, University of Technology, Vienna, Austria Helmut Pfützner, Institute of Electrodynamics, Microwave and Circuit Engineering, University of Technology, Vienna, Austria Georgi Shilyashki, Institute of Electrodynamics, Microwave and Circuit Engineering, University of Technology, Vienna, Austria Damir Šabić, Institute of Electrodynamics, Microwave and Circuit Engineering, University of Technology, Vienna, Austria Edin Mulasalihović, Institute of Electrodynamics, Microwave and Circuit Engineering, University of Technology, Vienna, Austria Viktor Galabov, Institute of Electrodynamics, Microwave and Circuit Engineering, University of Technology, Vienna, Austria Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Changes in permeability and magnetic losses in non-oriented electrical steel sheets resulting from compressive stress have been investigated using a single-sheet tester. A compressive stress of up to 20 MPa is uniformly applied normal to the sheet surface. It is demonstrated that a stress beyond 5 MPa can decrease magnetic losses, including both hysteresis loss and eddy current loss. Content Type Journal Article Pages - DOI 10.3233/JAE-141789 Authors Ken-Ichi Yamamoto, University of the Ryukyus, Nakagami, Okinawa, Japan Shunji Yanase, Gifu University, Yanagido, Gifu, Japan Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: In principle, single sheet testers (SSTs) or Epstein testers (ETs) determine iron losses p through the time integral over the field H and the time derivative of the induction B. Both quantities should be determined in equivalent ways, i.e. considering an identical quasi-homogeneously magnetized sample section. Partly, this condition is fulfilled by H-coil methods. However, the so far used very small coils do not meet the demand of equivalence. At least outside of Japan, most labs prefer apparatuses where H is assumed to be proportional to the magnetization current i. But exact proportionality does not exist due to the periphery – the yoke of SST and the corners of ET, respectively. Usually, the periphery is considered through a constant effective magnetic path length l_M based on the peak induction B_p. But in fact, l_M varies during the period, i.e. it is a function of B(t) and thus also of time. Our novel "PLC method" is characterized by path length consideration. We consider dynamics of length through a "path length function" Λ (B) which is determined for each grade of material in a calibration process by means of a large, rigid H-coil. Considering Λ [B(t)] by software, routine measurements on similar materials can be based on the "corrected" current i(t)/Λ (t). First results are presented for HGO SiFe investigated in an ET. Here, Λ proves to be above 1 for low B and below 1 for very high B. As a final target, application of the method for both ETs and SSTs should yield almost identical loss values that are close to "true" ones. Content Type Journal Article Pages - DOI 10.3233/JAE-141788 Authors Helmut Pfützner, Institute of Electrodynamics, Microwave and Circuit Engineering, University of Technology, Vienna, Austria Georgi Shilyashki, Institute of Electrodynamics, Microwave and Circuit Engineering, University of Technology, Vienna, Austria Martin Palkovits, Institute of Electrodynamics, Microwave and Circuit Engineering, University of Technology, Vienna, Austria Viktor Galabov, Institute of Electrodynamics, Microwave and Circuit Engineering, University of Technology, Vienna, Austria Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: We present the results of an international comparison regarding the magnetic properties of hard magnets, measured using the Vibrating Sample Magnetometer. The comparison involved eight different international laboratories, plus two laboratories using the SQUID magnetometer. It was directed, in particular, at the determination of the hysteresis loop parameters of hard ferrite and magnetic tape samples. It was carried out in the framework of the activity of the IEC TC68 Working Group 2. The statistical analysis of the obtained results was performed according to standard rules (e.g. ISO and EURAMET guidelines). The standard deviation around the mean of the laboratories best estimates is found to be s ∼ 1% in anisotropic ferrites for all the measured quantities: coercive fields H_{cJ} and H_{cB}, high-field polarization J_{800 k}, polarization at remanence J_r, maximum energy product (BH)_{max}. Isotropic ferrites show larger dispersion of the best estimates of J_r and H_{cB} (∼ 3%) and (BH)_{max} (∼6%). For the quantities measured in the magnetic tapes (magnetic moment under applied field H=400 kA/m m_{400 k} and at remanence m_r, squareness S = m_{400 k}/m_r, H_{cJ}) s is found to fluctuate around 2%. In all cases, the relative expanded uncertainty of the reference value (weighted mean), associated with a 95% confidence level, is at most ± 1.5%. Content Type Journal Article Pages - DOI 10.3233/JAE-141786 Authors F. Fiorillo, INRIM, Torino, Italy C. Beatrice, INRIM, Torino, Italy D. Son, Hannam University, Daejeon, Korea H. Ahlers, PTB, Braunschweig, Germany R. Groessinger, TU Wien, Austria F. Albertini, IMEM-CNR, Parma, Italy Y.P. Liu, China Jiliang University, Hangzhou, Zhejiang, China A. Lin, NIM, Bejing, China E. Patroi, INCDIE ICPE-CA, Bucharest, Romania R. Shull, NIST, Gaithersburg, MD, USA O. Thomas, NPL, Teddington, UK M.J. Hall, NPL, Teddington, UK Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Content Type Journal Article Category Guest Editorial Pages - DOI 10.3233/JAE-141785 Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: The standardized Epstein frame is a magnetic circuit for the normative measurements of magnetic properties of electrical sheet steel following the Wattmeter method. It was designed for convenient practical use in industry rather than as an accurate physical representation of magnetic power loss of the material. In principle, the Wattmeter method is based on the use of a homogeneous ring sample as the magnetic circuit. The double overlapping corners of the Epstein frame constitute a significant divergence from the topology of the homogeneous ring, and, thus, are the source of a substantial systematic error. This paper applies the simple method of summation of the reluctances of the complete magnetic circuit (CRS) for the determination of this error. The results for various types of electrical steel and for the frequency range of 40 Hz to 100 Hz are considered. Results of variations of the Epstein strip stacking scheme are also recorded. Content Type Journal Article Pages - DOI 10.3233/JAE-141787 Authors J. Sievert, Institute of Material Science and Engineering, China Jiliang University, Hangzhou, Zhejiang, China H. Yang, Institute of Material Science and Engineering, China Jiliang University, Hangzhou, Zhejiang, China P. Zhang, Institute of Material Science and Engineering, China Jiliang University, Hangzhou, Zhejiang, China H. Ge, Institute of Material Science and Engineering, China Jiliang University, Hangzhou, Zhejiang, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: The important research area associated with the Ultra-Sonic Motor (USM) is the contact problem between the stator and the rotor. Because the USM operates by the friction force between the rotor and the stator, the contact problem of the USM have to be taken into account to analyze the motor performance accurately. Consequently, various types of the analysis methods have been proposed based on a contact model which describes the complex nonlinear contact condition of the USM. In this paper, diverse types of contact analysis methods for a Travelling Wave Ultra-Sonic Motor (TWUSM) are clearly condensed and precisely examined. The governing equations for the analysis of the TWUSM performance are derived through a precise investigation of the relationship between the contact condition and the motor performance in this paper. Furthermore, the motor performance is analyzed using contact models and the calculated data are compared with the experimental results. Content Type Journal Article Pages 437-453 DOI 10.3233/JAE-141745 Authors Jong-Suk Ro, Brain Korea 21 Plus, Creative Research Engineer Development, Department of Electrical Engineering, Seoul National University, Shinlim-Dong, Kwanak-Gu, Seoul, Korea Sang-Yong Jung, School of Electronic and Electrical Engineering, Sungkyunkwan University, Suwon, Kyeonggi-Do, Korea Cheol-Gyun Lee, School of Electrical Engineering, Dong Eui University, Jin-Gu, Pusan, Korea Hyun-Kyo Jung, School of Electrical Engineering, Dong Eui University, Jin-Gu, Pusan, Korea Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416 Journal Volume Volume 46 Journal Issue Volume 46, Number 3 / 2014

Description: This study presents a high-performance single-sided portable nuclear magnetic resonance (NMR) sensor. The magnet array, which is composed of five identical cuboid permanent magnet blocks and two passive shimming sheets, generates a highly uniform B_{0} field in a 10 × 10 mm^{2} lateral area. Along the two orthogonal lines in this lateral area, the measured B_{0} strength variation is less than 338 ppm. Vertically, the measured B_{0} magnitude decreases from 144.387 mT to 130.603 mT, with a constant gradient of 4.6 T/m from 0.15 mm to 3.15 mm above the magnet surface. A planar radiofrequency coil is optimized according to the signal-to-noise ratio level of the coil. A one-dimensional profiling experiment on an oil film shows that a vertical resolution of approximately 1.7 μm can be achieved. As an application, the silicone rubber insulators are measured using the NMR sensor. Results demonstrate that the silicone rubber insulators with different service times can be distinguished through the transverse relaxation time T_{2} of the silicone rubber insulators. Content Type Journal Article Pages - DOI 10.3233/JAE-140123 Authors Zheng Xu, State Key Laboratory of Power Transmission Equipment and System Security and New Technology, Chongqing University, Chongqing, China Kaikai Meng, State Key Laboratory of Power Transmission Equipment and System Security and New Technology, Chongqing University, Chongqing, China Jiangyan Cheng, State Key Laboratory of Power Transmission Equipment and System Security and New Technology, Chongqing University, Chongqing, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: When HVDC transmission lines operate in the monopole ground return mode or asymmetric bipolar mode, DC current flows in the earth and DC magnetic bias will arise in neutral point grounding (NPG) transformers. In this work, the model to calculate the potential distribution for multi-layer soil structure is set up, then the magnetic bias current (MBC) is calculated. The magnetic field distribution in the NPG transformer is obtained according to MBC, and electromagnetic energy and force in the transformer are calculated. Finally, the influence on MBC, electromagnetic energy and force caused by soil parameters are investigated. Results indicate that thickness of the first layer and resistivity of the second layer have a greater contribution to MBC, electromagnetic energy and force. To avoid excessive vibration of the NPG transformer, the soil at grounding electrode with a greater thickness in the first layer and lower resistivity in the second layer is preferred. Content Type Journal Article Pages - DOI 10.3233/JAE-140122 Authors Fan Yang, State Key Laboratory of Transmission and Distribution Equipment and System Security and New Technology, School of Electrical Engineering, Chongqing University, Chongqing, China Feng Dai, State Key Laboratory of Transmission and Distribution Equipment and System Security and New Technology, School of Electrical Engineering, Chongqing University, Chongqing, China Xinghua Liu, Zibo Power Supply Company, Shandong Electric Power Corporation, Zibo, Shandong, China Yongming Yang, State Key Laboratory of Transmission and Distribution Equipment and System Security and New Technology, School of Electrical Engineering, Chongqing University, Chongqing, China Wei He, State Key Laboratory of Transmission and Distribution Equipment and System Security and New Technology, School of Electrical Engineering, Chongqing University, Chongqing, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: This paper focuses on the steering law for a magnetically suspended momentum wheel (MSMW) cluster with vernier gimballing capability. Firstly, the dynamical model of the spacecraft equipped with the MSMW cluster is constructed in a generalized form. Then a new steering law for the MSMW cluster is proposed to switch between two operation modes: the conventional momentum wheel mode for outputting spin torque, and the double gimbaled wheel mode for outputting the gyroscopic torques. Compared with the traditional steering law, the proposed steering law with two modes switch can avoid the small vernier gimbal angles saturation. Finally, simulation results demonstrate the merits of using vernier gimballing capability and the effectiveness of the proposed steering law in providing the command torques and avoiding the saturation of the vernier gimbal angles. Content Type Journal Article Pages - DOI 10.3233/JAE-140024 Authors Cong Peng, Key Laboratory of Fundamental Science for National Defense Novel Inertial Instrument and Navigation System Technology, Science and Technology on Inertial Laboratory, School of Instrumentation Science and Opto-Electronics Engineering, Beihang University, Beijing, China Jiancheng Fang, Key Laboratory of Fundamental Science for National Defense Novel Inertial Instrument and Navigation System Technology, Science and Technology on Inertial Laboratory, School of Instrumentation Science and Opto-Electronics Engineering, Beihang University, Beijing, China Chun'e Wang, Key Laboratory of Fundamental Science for National Defense Novel Inertial Instrument and Navigation System Technology, Science and Technology on Inertial Laboratory, School of Instrumentation Science and Opto-Electronics Engineering, Beihang University, Beijing, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: In this paper the Halbach array with different segments per pole are modeled and compared. The unified harmonic model for the magnetic flux density distribution of the Halbach array with different segments per pole is derived by using Fourier series and magnetic scalar potential. The coil power dissipation and higher harmonics are compared with the Halbach arrays, respectively. The dimension parameter of magnet array is optimized on the basis of minimum coil power dissipation by taking the magnetically levitated planar motor with moving magnets for example. The genetic algorithm is used to minimize the higher harmonics in z-component of the magnetic flux density distribution. Then the dimension parameters of magnet arrays are obtained, according to that the arrays are compared on the ratio between the higher harmonics and analytical model of z-component of the magnetic flux density distribution and the peak value of z- and x-component of the magnetic flux density distribution. The Halbach array with 3 segments per pole is chosen on the basis of the above comparison. Content Type Journal Article Pages - DOI 10.3233/JAE-130113 Authors Yunfei Zhou, School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, China Guangdou Liu, School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, China Rougang Zhou, School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, China Ligang Huo, School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, China Wuyi Ming, School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: The paper proposes a wideband bowtie antenna for indoor base station applications. By using the inverted L-shaped coupling feed structure, the impedance bandwidth of the lower band is improved; while using the four tuning stubs, the upper band is enhanced. Thus, a wide impedance bandwidth of about 77.8% (VSWR les; 2) ranging from 1.38 to 3.14 GHz is obtained. In addition, by connecting two folded elements to the patches of the bowtie dipole, the compact dimensions of the antenna can be achieved. It also provides stable peak gain, unidirectional radiation patterns and low cross-polarization over the whole operating band. Owing to these good performances, the proposed antenna is very suitable for the recent indoor base station wireless communication services such as 3G, WiFi, WiMax, Bluetooth and LTE applications, etc. Content Type Journal Article Pages - DOI 10.3233/JAE-140086 Authors Zhi-Ya Zhang, National Key Laboratory of Antennas and Microwave Technology, Xidian University, Xi'an, Shaanxi, China Shao-Li Zuo, School of Physics and Optoelectronic Engineering, Xidian University, Xi'an, Shaanxi, China Jia-Yue Zhao, National Key Laboratory of Antennas and Microwave Technology, Xidian University, Xi'an, Shaanxi, China Shao-Chuan Wang, National Key Laboratory of Antennas and Microwave Technology, Xidian University, Xi'an, Shaanxi, China Guang Fu, National Key Laboratory of Antennas and Microwave Technology, Xidian University, Xi'an, Shaanxi, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Integral equation method is widely used in magnetic field modeling of ships, but its nonsymmetric and dense coefficient matrix results in low computation efficiency and large memory, which limits its application in large scale problems. An approach for a fast computation of induced magnetic field created by ships was presented based on multiple layers fast multipole method and vector integral equation method. The numerical implementation of the proposed approach was described in detail. It is shown by an analytical sphere example and a simplified mock-up experiment that the proposed approach can reduce computation time and memory cost in induced magnetic field modeling of ferromagnetic objects. Content Type Journal Article Pages - DOI 10.3233/JAE-140113 Authors Guohua Zhou, College of Electrical Engineering, Naval University of Engineering, Wuhan, Hubei, China Shengdao Liu, College of Electrical Engineering, Naval University of Engineering, Wuhan, Hubei, China Changhan Xiao, College of Electrical Engineering, Naval University of Engineering, Wuhan, Hubei, China Daming Liu, College of Electrical Engineering, Naval University of Engineering, Wuhan, Hubei, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Tunable and multi-band metamaterial (MTM) based perfect microwave absorber (MA) is designed, implemented, and characterized. Firstly, dual-band MA with has two distinct resonances is investigated both numerically and experimentally which is also tested according the incident angle and polarization independencies. Then, the modified versions of MA are investigated and compared with respect to their absorbance, mechanical tunability, and multi-band characters. As a result, the suggested MAs with perfect absorption (including incident angle and polarization independencies) display good performance among their counterparts and can be used in myriad potential applications such as high frequency and sensor applications which are also presented. Content Type Journal Article Pages - DOI 10.3233/JAE-140073 Authors Furkan Dincer, Department of Computer Engineering, Mustafa Kemal University, Hatay, Turkey Muharrem Karaaslan, Department of Electrical and Electronics Engineering, Mustafa Kemal University, Hatay, Turkey Emin Unal, Department of Electrical and Electronics Engineering, Mustafa Kemal University, Hatay, Turkey Cumali Sabah, Department of Electrical and Electronics Engineering, Middle East Technical University – Northern Cyprus Campus, Kalkanli, Guzelyurt, Turkey Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Secondary arc is a complicated and critical physical phenomenon with power transmission lines. An arc chain model was employed with a view to establish the governing velocity equations, in which the multiple forces impacts upon each element were specifically incorporated including electromagnetic force, wind load, air resistance and thermal buoyancy. Based on the proposed model for secondary arc dynamics, simulations were then carried out and further validated through physical experiments on a test platform, which showed good coincidence between the two. The research can provide fundamentals for understanding the physical nature especially the extinction mechanism of secondary arcs, and lays theoretical basis for optimal design of the transmission lines' auto-reclosing strategy. Content Type Journal Article Pages - DOI 10.3233/JAE-140079 Authors Haoxi Cong, School of Electrical Engineering, Shandong University, Jinan, Shandong, China Qingmin Li, State key Lab of Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University, Beijing, China Quan Chen, School of Electrical Engineering, Shandong University, Jinan, Shandong, China Jinyuan Xing, State key Lab of Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University, Beijing, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Considering the torsional vibration in transmission system driven by AC asynchronous motor, this paper proposes a dynamical model of nonlinear electromechanical coupling system by using the energy method. The effect of electromagnetic factors on nonlinear dynamic performance of the electromechanical coupling system is investigated. Firstly, the static bifurcation characteristic under the non-autonomous condition is studied based on the singularity theory of nonlinear system. Secondly, the Hopf bifurcation point and the direction of bifurcation are determined based on the Hopf bifurcation theory. Finally, the bifurcation diagram, Poincare map and the largest Lyapunov exponent are given, which show the influence of electromagnetic stiffness and electromagnetic damping on the chaotic motions of the system. Content Type Journal Article Pages - DOI 10.3233/JAE-140059 Authors Shuang Liu, Key Laboratory of Industrial Computer Control Engineering of Hebei Province, Yanshan University, Qinhuangdao, Hebei, China Xue Li, Key Laboratory of Industrial Computer Control Engineering of Hebei Province, Yanshan University, Qinhuangdao, Hebei, China Shuangshuang Zhao, Key Laboratory of Industrial Computer Control Engineering of Hebei Province, Yanshan University, Qinhuangdao, Hebei, China Haibin Li, Key Laboratory of Industrial Computer Control Engineering of Hebei Province, Yanshan University, Qinhuangdao, Hebei, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: In order to actively maneuver the robotic capsule and make it small to swallow easily, we propose that the capsule incorporating the circuits, batteries, imaging device, etc. is looped by a magnet ring with 1 mm thickness. Another cuboidal or cylindrical permanent magnet attracts or pushes or rotates the robotic capsule to make closer scrutiny for the interesting area. Before designing the control system, the force regarding distance between cuboidal or cylindrical magnet and magnet ring should be known in advance. The mathematic model of magnetic force that the cuboidal or cylindrical permanent magnet exerts on the magnet ring is given for that purpose. The experiments state that the force the robotic capsule requires can be produced by cuboidal or cylindrical magnet when it's moving forward in the pig's small bowel. The experiments also show the relationships between the force and the shape of cuboidal magnet or cylindrical magnet, which can help to choose the magnets with optimal dimensions. Content Type Journal Article Pages - DOI 10.3233/JAE-140034 Authors Wan'an Yang, School of Computer and Information Engineering, Yibin University, Yibin, Sichuan, China Xin Zhao, School of Physics and Electronic Engineering, Mianyang Normal University, Mianyang, Sichuan, China Chao Hu, Ningbo Institute of Technology, Zhejiang University, Ningbo, Zhejiang, China Fengqing Qin, School of Computer and Information Engineering, Yibin University, Yibin, Sichuan, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: An analytic technique based on spectral plane wave representation of fields (SPRF) for the scattering of a plane wave from a perfectly electric conductor (PEC) cylinder coated with double positive (DPS) or double negative (DNG) materials buried beneath a slightly rough surface is formulated. Small Perturbation Method is used to consider scattering from rough surface. Spectral integrals are evaluated using saddle point method. A comparison with the previously available results has been done for validity. Both TM and TE polarizations are considered to obtain results varying different geometrical and physical parameters. Content Type Journal Article Pages - DOI 10.3233/JAE-130171 Authors M.A. Fiaz, Department of Electronics, Quaid-i-Azam University, Islamabad, Pakistan M.A. Ashraf, Department of Electronics, Quaid-i-Azam University, Islamabad, Pakistan Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Electromagnetic responses of a metallic conical frustum cabin with one coaxial feeding monopole antenna, illuminated by an intentional electromagnetic pulse (IEMP), are studied in this paper. There are several slots on the cabin wall with different sizes and orientations. The mathematical treatment is based on novel hybrid finite difference time domain (FDTD) method, where coaxial feeding, transfer impedance coupling and thin wire antenna models are integrated together for handling such a complex three-dimensional (3D) composite structure. The revised antenna port coupling model is verified by comparing the calculated terminal voltage responses of the coaxial feeding cable with that of commercial CST Microwave Studio. Parametric studies are further carried out to show the variations of its terminal voltages for different IEMP waveforms, incident directions and polarizations. Content Type Journal Article Pages - DOI 10.3233/JAE-140112 Authors Jian Wang, School of Information Science and Engineering, Ningbo University, Ningbo, Zhejiang, China Yin-Shui Xia, School of Information Science and Engineering, Ningbo University, Ningbo, Zhejiang, China Lun-Yao Wang, School of Information Science and Engineering, Ningbo University, Ningbo, Zhejiang, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: The recovery in a spark gap for repetitive switching has been a long research interest. The surface temperature variation of the anode during switching plays decisive role in recovery of spark gap. This paper presents a method to estimate the effect of anode temperature rise and decay on repetition rate of spark gap. By using this method, the behavior of copper and stainless steel materials were studied for a current pulse of 30 kA. During the pulse period of 10 μs, the temperature rise for SS is higher than Copper. After current zero, the anode temperature decays to the vaporization temperature of the material and determines the recovery time of the spark gap. This temperature decay is also verified by a heat transient computational model developed in FEM based software. Simulations has been carried out for different materials including Cu and SS. Some simulations are in good agreement with existing experimental data. The decay time for current pulses 5 kA, 10 kA, 15 kA, 20 kA, 25 kA and 30 kA are estimated. The simulation shows higher decay rate for tungsten and lower decay rate for graphite. Similar trend has been observed for silver and copper. Theoretical analysis of recovery times, heat transfer simulation model for different anode materials are presented and the results are discussed. Content Type Journal Article Pages - DOI 10.3233/JAE-140049 Authors C.S. Reddy, Accelerator and Pulse Power Division, Bhabha Atomic Research Centre, Mumbai, India A. Sharma, Accelerator and Pulse Power Division, Bhabha Atomic Research Centre, Mumbai, India K.C. Mittal, Accelerator and Pulse Power Division, Bhabha Atomic Research Centre, Mumbai, India Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: In this paper, a discrete-time domain synthesizing method was presented to design and implement the active integrator in the microwave frequency range. The frequency-domain GaAs Filed Effect Transistor (FET) scattering parameters are converted into the Z-domain representations. The transfer functions of the networks are formulated in the Z domain and implemented by using cascade serial line and GaAS FET. There are good agreement between the experimental results and the theoretical values. Content Type Journal Article Pages - DOI 10.3233/JAE-140042 Authors Yi-Hsien Tsai, Department of Electronic Engineering, National Taiwan University of Science and Technology, Taiwan Ching-Wen Hsue, Department of Electronic Engineering, National Taiwan University of Science and Technology, Taiwan I-Fong Chen, Department of Electronic Engineering, Jinwen University of Science and Technology, Taiwan Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: The use of magneto-plated wire (MPW) allows for reduction of winding loss component from the proximity effect. compared with a copper wire (COW). A MPW is a COW with a circumference that is plated with a magnetic thin film. In this paper, we clarify the basic characteristics and the efficiency characteristics of a transformer using a MPW and a COW. We found that the resistances of a primary coil made of COW and MPW at a frequency f=500 kHz are 1.56 Ω and 1.12 Ω, respectively, and decreased 28%. The short circuit inductances of the COW and the MPW at a frequency f=500 kHz are 26 μH and 29.6 μH, respectively, and increased 13.8%. The efficiencies of an LLC resonant converter using the COW and the MPW at a frequency f=500 kHz are 90.2% and 92.2%, respectively, and increased 2%. Content Type Journal Article Pages - DOI 10.3233/JAE-140070 Authors Yinggang Bu, Faculty of Engineering, Shinshu University, Nagano, Japan Masahiro Nishiyama, Faculty of Engineering, Shinshu University, Nagano, Japan Tatsuya Yamamoto, Faculty of Engineering, Shinshu University, Nagano, Japan Tsutomu Mizuno, Faculty of Engineering, Shinshu University, Nagano, Japan Shigeaki Tsuchiya, TOTOKU Electric Co., Ltd., Shinbashi 6-Chome, Minato-ku, Tokyo, Japan Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Magnetic Bearing, especially Active Magnetic Bearing (AMB) is arguably most preferred bearing for the process dealing with highly reactive environment, high speed operation and where the process required least contamination. They are also being tried for Fly wheels and Wind generators. They continue to be evolved since last several decades. Quite a few processes like application of AMB in high temperature Liquid Sodium high temperature applications call for development of large-working-gap active magnetic bearings (AMB). Smooth operation of AMB depends on hypersensitive position stiffness and Current stiffness, which fluctuates due to differential-thermal-expansion induced air gap variation. So, large gap, necessitates flatter open loop position stiffness than that of contemporary magnetic actuators. In this work, a goal seeking optimization methodology is employed for double acting AMB system where a combination of higher (CRGO electrical steel) and lower saturating magnetic material (Mu metal) is used. A less variant position stiffness across the air gap was arrived at after getting optimized design variables constituting geometry and excitation current parameters. This investigation opens up a new way to attain position stiffness in AMB system which is less sensitive to positional variation of rotor in air gap. This paper proposes an innovative and first-of-its-kind bi-material core material with goal driven optimized magnetic actuator design which can afford to have air gap variation during operation. Content Type Journal Article Pages - DOI 10.3233/JAE-140041 Authors S.K. Dash, Fast Reactor Technology Group, Indira Gandhi Center for Atomic Research, Kalpakkam, Tamil Nadu, India K.S. Swarup, Department of Electrical Engineering, IITM, Chennai, India K.K. Rajan, Fast Reactor Technology Group, Indira Gandhi Center for Atomic Research, Kalpakkam, Tamil Nadu, India Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: In this paper, a theoretical and practical investigation on microwave dielectric materials for wideband dielectric resonator antennas (DRAs) is presented. Due to the variety of materials available to antenna designers, a proper technique to select the best possible material is required. In this paper Ashby's material selection methodology is used for dielectric material based antenna systems. Four primary performance indices, impedance bandwidth (BW), the size of the antenna (λ), radiation efficiency (η) and resonance frequency (f_{0}), are used to obtain the desired performance. The selection chart shows that Roger TMM10, (ε_{r}= 9.8) is the most suitable material followed by "Roger's TMM10i and RO3010" for DRAs to provide the best performance for wideband applications. Performances of antenna are verified with rectangular and hybrid design of DRA in terms of reflection coefficients, radiation pattern gain and efficiency. Theoretical work is compared with the simulation and the close agreement between the two, confirm the validity of this study. Content Type Journal Article Pages - DOI 10.3233/JAE-140051 Authors Jitendra Kumar, Department of Electrical and Electronics Engineering, Birla Institute of Technology and Science, Pilani, Rajasthan, India Navneet Gupta, Department of Electrical and Electronics Engineering, Birla Institute of Technology and Science, Pilani, Rajasthan, India Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Though electromagnetic interference (EMI) shielding fabric with rectangular hole has wide application in various fields, there is not a mature approach to calculate its shielding effectiveness (SE) at present. This paper constructs a rapid computation model of the SE of the EMI shielding fabric with hole based on equivalent coefficient. Firstly, the rectangular hole characteristic is analyzed and a structure model of the rectangular hole under the consideration of the hole edge characteristic is described. The equivalent relationship between the fabric hole and the standard hole is presented according to the equivalent theory. The rapid computation model of the SE of the EMI shielding fabric with hole is built including the equivalent coefficient and transmission coefficient according to the EMI shielding theory and the method to determine the equivalent coefficient is also given. Finally, the computation model is verified by experiments. The results show that the accuracy and the computational efficiency of the proposed model are good, and the model can be applied to the fabrics with wide weaves and various rectangular hole sizes. Content Type Journal Article Pages - DOI 10.3233/JAE-140023 Authors Xiuchen Wang, Zhongyuan University of Technology, Zhengzhou, Henan, China Zhe Liu, Zhongyuan University of Technology, Zhengzhou, Henan, China Zhong Zhou, Zhongyuan University of Technology, Zhengzhou, Henan, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Due to V-belt continuously variable transmission (CVT) driven electric scooter with unknown nonlinear and time-vary characteristics, an accurately dynamic modeling of V-belt CVT driven electric scooter is the time-consuming procedure for the linear controller design. A hybrid modified recurrent Legendre neural network (NN) control system is proposed to control the V-belt CVT driven electric scooter under the occurrence of nonlinear load disturbances with parametric variations in order to acquire good control performance. Firstly, system structure of the V-belt CVT driven electric scooter by using a permanent magnet synchronous motor (PMSM) servo drive system is proposed in this study. Secondly, the hybrid modified recurrent Legendre NN control system, which consists of an inspector control, a modified recurrent Legendre NN control with adaptive law and a recouped control with estimated law, is proposed to control the V-belt CVT driven electric scooter by using PMSM servo drive. Moreover, the on-line parameters tuning methodology of the modified recurrent Legendre NN is derived according to Lyapunov stability theorem and gradient descent method. Furthermore, two optimal learning rates of the parameters in the modified recurrent Legendre NN are developed to speedup convergence. Finally, to show the effectiveness of the proposed control scheme, comparative studies are demonstrated by simulated and experimental results. Content Type Journal Article Pages - DOI 10.3233/JAE-140035 Authors Lin, Department of Electrical Engineering, National United University, Miao Li 36003, Taiwan. Tel.: +886 3 7381349; Fax: +886 3 327887; E-mail: jhlin@nuu.edu.tw Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: A compact printed ultra-wideband (UWB) antenna with two notched stop bands is analyzed and presented. By introducing a unit complementary split ring resonator (CSRR) in the beveled edges of radiating patch, two sharp notches are achieved at frequencies of 3.5 and 5.8 GHz. The proposed antenna has been fabricated and experimentally tested. A good agreement between simulated and measured results has been observed. Measured impedance bandwidth of the tested antenna is 3.12–12 GHz, which covers bandwidth requirement of UWB frequency band, for VSWR 〈 2 and also has two notched stop bands of 3.39–3.90 and 5.52–6.44 GHz, for VSWR 〉 2, for rejecting WiMAX and WLAN band signals, respectively. In addition, the effect of the dimensions of the CSRR on the two stop bands is also analyzed. The radiation pattern and gain characteristics of the proposed configuration are studied and the results are exhibited accordingly. Content Type Journal Article Pages - DOI 10.3233/JAE-140007 Authors M.M. Sharma, Government Engineering College, Ajmer, India J.K. Deegwal, Department of Electronics and Communication Engineering, Suresh Gyan Vihar University, Jaipur, India M.C. Govil, Department of Computer Engineering, Malaviya National Institute of Technology, Jaipur, India Ashok Kumar, Department of Electronics and Communication Engineering, Government Women Engineering College, Ajmer, India Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: We study the scattering of time harmonic electromagnetic plane wave from a topological insulator circular cylinder in chiral medium. Variation of scattering behavior for different values of radii and permittivity of the cylinder is noted when time reversal symmetry is protected and we also studied the scattering behavior when time reversal symmetry is broken. Although scattering behavior of co-polarized component of field is not significantly different from chiral cylinder in chiral medium yet it is found that the same, when time reversal symmetry broken, is similar to scattering from a perfect conductors. Scattering behaviour of cross-polarized field component of topological cylinder in chiral medium is remarkably different from chiral cylinder i.e. it has stronger scattering possibly due to the presence of conducting states near the surface. Moreover, it is noted that the scattering in forward direction for cross-polarized and co-polarized components are not correlated with permittivity but for carefully selected values of permittivity, we can control the scattering behavior of topological insulator circular cylinder. Content Type Journal Article Category 1 Pages - DOI 10.3233/JAE-140039 Authors Faheem Ashraf, Department of Electronics, Quid i Azam University, Pakistan S. Ahmed, Department of Electronics, Quid i Azam University, Pakistan A.A. Syed, Department of Electronics, Quid i Azam University, Pakistan Q.A. Naqvi, Department of Electronics, Quid i Azam University, Pakistan Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: We study the electrohydrodynamic capillary instability of the interface between two uniform superposed viscous and electrically conducting fluids in the presence of a free surface charge, when there is heat and mass transfer across the interface. The fluids are subjected to the uniform electric field in the axial direction and the viscous potential flow theory is used for the investigation. A quadratic dispersion relation that accounts for the growth of disturbance waves is derived for the linear stability analysis and the stability of the system is analyzed theoretically and numerically. The stability criterion is given in terms of the critical value of applied electric field as well as critical wave number. Various graphs with respect to physical parameters such as electric field, heat transfer coefficients, conductivity and permittivity ratio are drawn and effect of various parameters is described. It is observed that free surface charge and electric field both have stabilizing effect on the stability of the system. Content Type Journal Article Pages - DOI 10.3233/JAE-140009 Authors D.K. Tiwari, Department of Mathematics, Indian Institute of Technology Roorkee, Roorkee, India Mukesh Kumar Awasthi, Department of Mathematics, Indian Institute of Technology Roorkee, Roorkee, India G.S. Agrawal, Department of Mathematics, Indian Institute of Technology Roorkee, Roorkee, India Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Electro-hydraulic power units are key components of hybrid driven mobile machines such as forklifts and excavators. To satisfy the requirement of limited installation space, this paper proposes a compact and reversible electro-hydraulic energy conversion unit which is the integration of an axial piston hydraulic pump/motor and an electrical machine excited by a segmented Halbach permanent magnet array. The magnets are fixed on the surface of a barrel so that the hydraulic rotor and the electrical rotor are integrated together. Analytical and numerical methods are used to investigate the coupling issues including the common rotor's effect on flux density distribution, combined torque ripple, flow and energy losses in the oil gap, and some design criteria are presented to provide further development with references. Content Type Journal Article Pages - DOI 10.3233/JAE-140004 Authors Tao Wang, College of Mechanical and Vehicle Engineering, Hunan University, Changsha, Hunan, China Qingfeng Wang, The State Key Laboratory of Fluid Power Transmission and Control, Zhejiang University, Hangzhou, Zhejiang, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: MEMS piezoelectric energy harvester is optimally designed and fabricated, and its vibration characteristics, output voltage, power, power spectral density (SD) and frequency response function under harmonic and random excitation is studied by theory analysis, simulation and experimental test. For the designed MEMS piezoelectric energy harvester, the accurate solutions and expressions of amplitude, voltage, power and power spectral density are derived. Then, vibration characteristic, voltage, power and power SD with different load resistance, sinusoidal acceleration and random acceleration SD are simulated and tested; moreover, frequency response function of MEMS piezoelectric energy harvester is obtained by experimental test, and the results are consistent with theoretical model. When sinusoidal acceleration is 0.6 g, the maximal amplitude of mass is 116 μm and the power density is 0.1 mW/cm^{3}. By testing results, output voltage of piezoelectric energy harvester is proportional to the amplitude, and the amplitude at optimal load is smaller than of at open circuit because of the feedback effect of load resistance. In addition, output power SD linearly increase with acceleration SD increasing. When acceleration SD is 5 × 10^{-4} (m/s^{2})^{2}/Hz, power SD is 1.24 μW^{2}/Hz. Content Type Journal Article Pages - DOI 10.3233/JAE-140002 Authors Ping Li, State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing, China Shiqiao Gao, State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing, China Huatong Cai, State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing, China Yan Cui, Key Laboratory for Precision and Non-traditional Machining Technology of the Ministry of Education, Dalian University of Technology, Dalian, Liaoning, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: In this article, analysis of slot loaded compact rectangular patch antennas have been presented theoretically using circuit theory concept. The theoretical investigations of L-strip fed slot loaded compact rectangular microstrip patch antenna parameters such as return loss, VSWR, radiation pattern have been calculated. It is found that antenna resonates at 2.95 GHz and 6.01 GHz for lower and upper resonance frequencies respectively. The bandwidth of the L-strip fed slot loaded compact rectangular microstrip patch antenna at lower resonance frequency is 1.16% (simulated) and 10.16% (theoretical) whereas at upper resonance frequency, it is 1.5% (simulated) and 2.51% (theoretical). The characteristics of the L-strip fed slot loaded compact rectangular microstrip patch antennas is compared with other rectangular patch antennas. Circuit diagram of this antenna is proposed, fabricated and simulated using AWR circuit simulator. The theoretical results are compared with IE3D and AWR simulation results along with measured results and they are in close agreement. Content Type Journal Article Pages - DOI 10.3233/JAE-140020 Authors Ashish Singh, Department of Electronics and Communication, University of Allahabad, Allahabad, India J.A. Ansari, Department of Electronics and Communication, University of Allahabad, Allahabad, India Kamakshi, Department of Electronics and Communication, University of Allahabad, Allahabad, India Mohd. Aneesh, Department of Electronics and Communication, University of Allahabad, Allahabad, India Saiyed Salim Sayeed, Department of Electronics and Communication, University of Allahabad, Allahabad, India Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: A 3-phase flux-reversal motor (FRM) driven by a 6-switch converter has been studied for its various merits such as a low inertia, a high efficiency and fault tolerance. However, it is needed to develop the FRM with a 4-switch converter to reduce motor and converter construction costs. Among the many different 4-switch converter topologies, the one with a compensated current regulation base on a novel pulse width modulation (PWM) control technique has been proposed as a good solution. In this paper, we introduce a two dimensional time-stepped voltage source finite-element method (2D-FEM) to analyze the FRM driven by the proposed 4-switch converter. We also compare the characteristics of the FRM when the compensated current regulation is adopted or not. To verify the analysis method and simulated results, the 4-switch converter and the prototype FRM are built and experiments are performed. Content Type Journal Article Pages - DOI 10.3233/JAE-130065 Authors Tae Heoung Kim, Department of Electrical Engineering, Engineering Research Institute, Gyeongsang National University, Jinjudaero 501, Jinju-si, Gyeongnam 660-701, Korea. Tel.: +82 55 772 1717; Fax: +82 55 772 1719; E-mail: ktheoung@gnu.ac.kr Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: In this paper, a kind of efficient solution to the trihedral corner reflector's (TCR's) radar cross section (RCS) is proposed. Based on the combination of geometrical optics (GO) and Gordan surface integral method, TCR's RCS was computed and was compared with the results from computational electromagnetics software FEKO. Good agreement and significant speedup achieved show that the method mentioned in this paper is capable of practical rapid simulation and design, especially suitable for electrically large plate structure. Content Type Journal Article Pages - DOI 10.3233/JAE-130156 Authors Yin-Kan Weng, School of Electronic Information, Wuhan University, Wuhan, Hubei, China Song Li, School of Electronic Information, Wuhan University, Wuhan, Hubei, China Jin-Ling Yang, School of Electronic Information, Wuhan University, Wuhan, Hubei, China Hui Zhou, School of Electronic Information, Wuhan University, Wuhan, Hubei, China Hong Yi, School of Electronic Information, Wuhan University, Wuhan, Hubei, China Hong Wang, School of Electronic Information, Wuhan University, Wuhan, Hubei, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416

Description: Traditional synchronous motor system has complicated structure and is difficult to maintain. In view of the mentioned problem, this paper aims to propose a new structure brushless synchronous motor where AC exciter and synchronous motor using the same core. Two concentric single-phase winding grooves are cut on stator and rotor respectively, with the stator single-phase field winding laying in the stator single-phase winding groove, and the rotor AC induction winding laying in the rotor single-phase winding groove. The AC power from AC exciter is rectified by the rotating rectifier for the DC field winding. The results of the proposed structural design and FEA of the new structure brushless wound field synchronous motor show that the new structure is simple in structure, low in loss, high in efficiency and promising in its future application. Content Type Journal Article Pages - DOI 10.3233/JAE-140071 Authors Kun Hu, School of Information and Electrical Engineering, China University of Mining and Technology, Xuzhou, Jiangsu, China Fengyou He, School of Information and Electrical Engineering, China University of Mining and Technology, Xuzhou, Jiangsu, China Journal International Journal of Applied Electromagnetics and Mechanics Online ISSN 1875-8800 Print ISSN 1383-5416