International Journal of Applied Electromagnetics and Mechanics - Volume Pre-press, issue Pre-press

Authors: Wang, Zhen | Liu, Chunting | Wei, Weizhong

Article Type: Research Article

Abstract: The use of magnetic separation based on nanoparticles has been an efficient approach in many research fields and different industries. It has shown multiple advantages including high separation efficiency and fast separation speed as well as low cost, comparing to conventional sedimentation or centrifugation methods. The basic contents and modelling principles such as one-way and two-way coupling methods involving magnetic separation have been introduced specifically and comprehensively, which can be used for better understanding the process and optimizing design of magnetic separators. Then typical industry applications of magnetic separation including kaolin beneficiation, water treatment, protein purification, cell separation, and drug …delivery have been summarized in detail. Show more

Keywords: Magnetic separation, magnetic nanoparticle, industry applications, modelling

DOI: 10.3233/JAE-180087

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-17, 2019

Authors: Zhang, Jian-ping | Wang, Shuai | Xu, Da-cheng | Hu, Dan-mei | Wu, Helen

Article Type: Research Article

Abstract: In order to investigate the PM2.5 collection efficiency of a wire-cylinder electrostatic precipitator (ESP) under the action of ionic wind, PM2.5 removal mechanism was studied, and an ESP mathematic model including the multi-field coupling between gas flow field, electric field and particle dynamical field was built. By applying Deutsch-Anderson Equation to process and analyze the numerical solution after compiling user-defined function (UDF) program and linking it to Fluent, grade collection efficiency and overall collection efficiency for PM2.5 were obtained. Numerical results indicate that PM2.5 removal performance under the consideration of ionic wind is better, and the contribution of ionic wind …to PM2.5 removal performance is different by changing operating voltage and gas velocity. The research results can provide references for researchers to design a novel wire-cylinder ESP. Show more

Keywords: Multi-field coupling, wire-cylinder ESP, ionic wind, PM2.5, removal performance

DOI: 10.3233/JAE-180095

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-13, 2019

Authors: Xu, Meimei | Liu, Guohai | Chen, Qian

Article Type: Research Article

Abstract: This paper introduces a low torque ripple ferrite assisted synchronous reluctance motor (FASRM), in which an asymmetrical rotor is designed. The key of the proposed FASRM is to minimize the reluctance torque ripple, which is the main source of the total torque ripple. A compensation method is proposed to optimize the opening angle of each flux barriers, which indicates this pole producing torque with consistency in phase and waveform. Moreover, two existing motors with the same dimension are used as benchmarks in order to evaluate the proposed FASRM. Additionally, both theoretical analysis and simulation results are provided to validate the …good performances of the proposed FASRM. It is found that the proposed FASRM with the asymmetrical rotor can reduce the total torque ripple and avoid sacrificing the average torque. Show more

Keywords: Ferrite assisted synchronous reluctance motor, asymmetrical rotor, finite-element method, reluctance torque ripple

DOI: 10.3233/JAE-180084

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-10, 2019

Authors: Wang, Liping | Chen, Renwen | Ren, Long | Xia, Huakang | Zhang, Yuxiang

Article Type: Research Article

Abstract: A bistable magnetoelectric vibration energy harvester using nonlinear magnetic force is proposed. It consists of a planar spring, a magnetoelectric transducer with an annular magnetic circuit, and a coil assembly with a ferrite bobbin inside. Based on these, a nonlinear magnetic force between the ferrite bobbin and permanent magnet arrays can be generated when the relative displacement changes, which can broaden the operating frequency bandwidth of the harvester. The nonlinear magnetic force makes the harvester demonstrate some special dynamic behaviors including the inter-well and chaotic motions, which are performed by the finite element analysis. And, the experimental validations are also …carried to verify the performance of the proposed harvester. The results show that the output power can reach 10 mW in a relatively wide operating frequency range with a 90 Ω resistance load under 1 g harmonic excitation. In addition, a real vehicle road’s vibration signals from a highway bridge are acquired to estimate the practical energy harvesting performance of the harvester. The results show that the RMS output voltage and load power of the harvester can reach 3.16 V and 110.95 mW under 10× road spectrum excitations, respectively. Show more

Keywords: Vibration energy harvester, broadband, magneto electric, nonlinear magnetic force, bistable

DOI: 10.3233/JAE-180074

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-14, 2019

Authors: Liu, Zenghua | Zhang, Yongchen | Li, Aili | Xie, Muwen | Bin, Wu | He, Cunfu

Article Type: Research Article

Abstract: With the non-dispersion characteristics, the lowest shear horizontal mode SH0 can be widely applied in the detection and monitoring of a defect in plate structures. In order to achieve SH0 mode excitation in aluminum plates, based on Lorentz force mechanism, a new directional SH0 mode EMAT based on periodic grating coil (PGC), called PGC-EMAT, is designed in the study. On the surface of the aluminum plate, the PGC produces the horizontal eddy current. The oppositely induced eddy currents are generated by the adjacent grating units. The current I of the multiple wires in each grating unit …is the same. The rectangular magnet provides the static magnetic field perpendicular to the surface of the aluminum plate. In addition, the PGC-EMAT with different grating units of the periodic grating coil and coil layers are simulated by three-dimensional finite element simulation. The simulation results show that with the increase of grating units of the periodic grating coil, the tangential displacement of PGC-EMAT will increase, and the tangential displacement of double-layer periodic grating coil is larger than that of single-layer periodic grating coil when the number of grating units of the periodic grating coil is the same. The developed EMAT can excite and receive a single SH0 mode and the actual center frequency of the transducer coincides with the theoretical value. It was proved that the central frequency of the transducer was controlled by the distance between the adjacent grating units of the periodic grating coil. In order to increase the energy of the signals excited or received by PGC-EMAT, the number of cycles of grating units and the number of layers of the transducer were studied. The experimental results showed that there was a linear relationship between the number of cycles of the grating units and the energy of the excited and received signals. The energy of the excited and received signals of the double-layer PGC-EMAT was larger than that of the single-layer PGC-EMAT when PGC-EMAT was used as excitation transducer or receiving transducer. The simulation results were experimentally verified. The developed PGC-EMAT can be applied in defect detection. Show more

Keywords: Ultrasonic guided waves, shear horizontal mode, electromagnetic acoustic transducer, periodic grating coil, metal plate

DOI: 10.3233/JAE-180120

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-19, 2019

Authors: El Wahed, Ali K. | Balkhoyor, Loaie B. | Wang, HaoChen

Article Type: Research Article

Abstract: In this paper, the design and performance of a multi-degree-of-freedom smart ball-and-socket actuator and its application to rehabilitation training systems are investigated. A key feature of this actuator is the use of magnetorheological fluids which can exhibit dramatic changes in their rheological properties, including yield stress, when subjected to external magnetic fields. These fast and reversible fluid rheological changes permit the smart actuator to provide the required impedance at orthotic arm joints aimed for upper-limb rehabilitation. Electromagnetic finite element analyses using ANSYS software were carried out to design the electromagnetic circuit of the actuator and important design factors affecting …the efficiency of the generated magnetic field and its best delivery to the MR fluid, were examined. These factors included the relative permeability of the magnetic material and the electromagnetic coil properties such as its shape, size and location. In addition, the utilisation of non-magnetic materials in the electromagnetic circuit design was investigated with the aim to optimise the performance of the smart actuator. Finally, the performance of the smart actuator was assessed theoretically and numerically under various input conditions in which Bingham plastic fluid characteristics were assumed, and the results determined by the two techniques were found to compare well. Show more

Keywords: Magnetorheological fluids, electromagnetic design, ball-and-socket actuator

DOI: 10.3233/JAE-170039

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-16, 2019

Authors: Al Eit, Moustafa | Clénet, Stéphane | Henneron, Thomas | Guyomarch, Féderic

Article Type: Research Article

Abstract: In this paper we present a-priori model reduction technique that enables to take full advantage of the periodicity existing in the stator and rotor geometrical structures of electrical machines in order to reduce the computational time. Firstly, a change of basis is performed by applying two distinct discrete Fourier transformations on the stator and rotor periodic structures independently. Secondly, the Schur complement is introduced in the new spectral basis, to allow a parallel solving of the resulting block-diagonal matrix systems. Moreover, the using of a matrix-free Krylov method based on the conjugate gradient solver has verified an efficient solving of …the equation system associated to the stator-rotor interface. Furthermore, in the peculiar case of balanced supply conditions, a model order reduction can be carried out by considering only the dominant discrete Fourier transform components. This model reduction approach is applied on a buried permanent magnet machine and has successfully shown its efficiency under balanced and unbalanced conditions. Show more

Keywords: Finite-element analyses, model reduction, geometrical periodicity, discrete Fourier transform, electromagnetic fields, rotating electrical machines, buried permanent magnet machines, Schur complement

DOI: 10.3233/JAE-180067

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-26, 2019

Authors: Han, Xiaoming | Liu, Zheng | Li, Guofeng | Wang, Zhen | Wu, Ziku | Wu, Yan

Article Type: Research Article

Abstract: This paper presents a Radial Basis Function (RBF) and Finite Element Method (FEM) hybrid approach to solve a 3-D electromagnetic problem. The proposed method divides the entire computational domain into a series of sub-domains. The shape functions of each sub-domain are obtained by point interpolation method based on RBF to improve fitting performance of FEM. Each sub-domain consists of Galerkin FEM elements in the entire computational domain. To validate the proposed method, a case study is carried out based on a dual-electrode DC arc furnace. The results demonstrate that RBF and FEM hybrid approach in this paper is superior to …the traditional FEM. Show more

Keywords: Finite element method, radial basis function, magnetic vector potential, three dimensional (3-D)

DOI: 10.3233/JAE-180059

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-11, 2019

Authors: Yan, Shiwei | Lei, Yu | Huang, Shangyu | Wang, Qiong | Zhou, Mengcheng | Hu, Jianhua | Zou, Fangli

Article Type: Research Article

Abstract: Electromagnetic compaction is a preferable high energy rate forming process for brazing powders to improve the brazing performance. The dynamic analysis of electromagnetic compaction of Ag-Cu-Sn multivariate mixed metal powders was conducted by an electromagnetic-mechanical-thermal coupled model and electromagnetic compaction tests. The coupled model consists of electrical circuit model, electromagnetic field model, kinematic model of driving board, thermal field model and powder compaction model, it can be used to make a complete dynamic analysis of the electromagnetic compaction including discharge current, eddy current, mutual interactions of magnetic fields, kinematic motion of driving board, compaction densification behaviors and the energy transfer. …The electromagnetic compaction tests of Ag-Cu-Sn multivariate mixed metal powders were carried out with a self-developed WG-IV electromagnetic forming machine. The electromagnetic-mechanical-thermal coupled model has good agreement with the electromagnetic compaction tests, and can provide a more accurate dynamic analysis and optimized process design of electromagnetic compaction. An optimization study for higher relative density was completed by the coupled model, and the brazing performance of the optimized brazing sheet with higher relative density was evaluated to be advantageous in the brazing performance tests. Show more

Keywords: Electromagnetic compaction, dynamic model, optimization study, brazing performance

DOI: 10.3233/JAE-180021

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-20, 2019

Authors: Jin, Zhijia | Sun, Xiaodong | Yang, Zebin | Wang, Shaohua | Chen, Long | Li, Ke

Article Type: Research Article

Abstract: In this paper, a novel bearingless permanent magnet machine (BPMM) without strong and complex magnetic field coupling, which can limit four degree-of-freedoms (DOFs) independently, is presented for the flywheel energy storage system (FESS). The proposed machine provides suspension force by means of interaction of flux density between the permanent magnet rings and the winding current. Afterwards, the structure parameters have been designed and the model of the proposed machine is derived. Meanwhile, based on the conventional cross feedback control, the modified control scheme with compensation for cross channels is illustrated. Additionally, combining with the machine model and modified cross feedback …controller, the simulation is built to demonstrate the effectiveness. The results show smaller fluctuation in steady state, fast response with disturbance and less impact on undisturbed channels by employing the modified control. Show more

Keywords: Bearingless permanent magnet machine, suspension force, structure design, finite element analysis, cross feedback control

DOI: 10.3233/JAE-180115

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-15, 2019

Authors: Gao, Hui | Yu, Xiaohui | Cao, Jianan

Article Type: Research Article

Abstract: The structure of maglev flywheel battery is designed and the linear electromagnetic force is analyzed in his paper to study the beat phenomenon. Taylor expands the electromagnetic force to analyze the linearization and to build dynamic vibration model. To analyze the beat phenomenon of the maglev flywheel battery system, an accurate analytical model including controller effects and unbalance force effects is proposed. The general dynamic stiffness is defined and the unbalance response is analyzed in the model. Both the free vibration and the forced vibration are analyzed according to the model, and therefore the beat vibration is discovered. The influences …and weakening of the beat vibration are also discussed through adjusting the control currents and the inherent frequency. The simulation results and experimental results demonstrate the validity of the analysis. The accurate analytical model can provide simulation platform for the AMB system vibration compensation research. Show more

Keywords: Maglev flywheel, mechanical model, unbalance vibration, generalized dynamic stiffness, unbalance compensation

DOI: 10.3233/JAE-170154

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-13, 2019

Authors: Lahyaoui, Otmane | Lanfranchi, Vincent | Buiron, Nicolas | Martin, Floran | Aydin, Ugur | Belahcen, Anouar

Article Type: Research Article

Abstract: Soft ferromagnetic materials constitute the main components of magnetic circuits in electromechanical devices. However, their magnetic and magnetostrictive properties are strongly affected by mechanical loading. This can lead to a decrease in the performance and the efficiency of these devices and to a potential increase of the emitted noise. Aware of the importance of these factors, this paper proposes to study the effect of the mechanical stress on the magnetic and magneto-elastic properties of non-oriented electrical steel sheets. The stress dependency of permeability and Villari effect has been studied. Measurements of the magnetostrictive strain under applied stress are presented and …the anisotropic behavior under stress is described. Moreover, the ΔE effect has been observed and analyzed. The novelty of this work is the extension of the measurements to many directions of cut with respect to the rolling direction under tensile and compressive stress, as well as the demonstration of the magnetic and magnetostrictive anisotropy under uniaxial stress. Show more

Keywords: Magnetostriction, magnetization, mechanical stress, magneto-elastic effect, non-oriented electrical steel, magnetic material, anisotropy

DOI: 10.3233/JAE-180106

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-14, 2019

Authors: Liu, Gang | Jin, Zhiming | Zhao, Xiaojun | Yuan, Dongwei | Li, Lin

Article Type: Research Article

Abstract: The voltage on the valve side windings of the converter transformer is non-sinusoidal, which contains many high-order harmonic components. To calculate the nonlinear electric field distribution under the non-sinusoidal voltage, the harmonic-balanced decomposition finite element method (HBDFEM) is proposed in this paper. By using the fixed-point method, the finite element stiffness matrix of each iteration is decomposed according to the harmonic order, by which the memory consumption can be remarkably reduced. To verify the effectiveness of the proposed algorithm, a typical model of the oil-paper insulation structure is taken for instance, and the results obtained by the HBDFEM is compared …with two algorithms, the traditional HBFEM and the time step method. The calculation results show that the HBDFEM can effectively reduce the computation cost for the nonlinear electric field problems with the non-sinusoidal periodic voltage. And it can be applied to analyze the compound electric field problems of the actual converter transformer. The electric field distribution of a ±500 kV converter transformer is calculated and analyzed considering the nonlinear relationship between the electric field and the medium conductivity. Show more

Keywords: Converter transformer, fixed-point, finite element method, electric field, harmonic-balanced method

DOI: 10.3233/JAE-180080

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-15, 2019

Authors: Shao, Yan | Xu, Minglong | Song, Siyang | Tian, Zheng | Shao, Shubao

Article Type: Research Article

Abstract: Inertial piezoelectric rotary actuators have been driving interests of researchers major in precision machining and precision positioning. It has great significances to model inertial driving principle more accurately and design rotary actuators with simpler structure and higher resolution. In this paper, an inertial rotary actuator with one piezoelectric element is proposed. The theoretical development and experiments of the actuator are presented. The verification of developed model proves that the model has great potentials on designing and optimizing the stick-slip rotary actuators. The experimental test of the actuator shows that stepping characteristic depends greatly on the input voltage parameters and the …frictional force. This designed rotary actuator achieves the minimum resolution of 0.58 μrad with simple configuration. Show more

Keywords: Micropositioning, piezoelectric materials, rotary actuator, stick-slip principle

DOI: 10.3233/JAE-171159

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-8, 2019

Authors: Kida, Masahiro | Oda, Yoshiho | Suzuki, Toshiki | Narita, Takayoshi | Kato, Hideaki | Moriyama, Hiroyuki

Article Type: Research Article

Abstract: Thin steel plates are widely used in various industrial products. However, deterioration of their surface quality and metal plating occur to movement. As a solution to these problems, non-contact transportation of a steel plate using electromagnetic force has been proposed. In this study, a thin steel plate (0.24 mm thickness) was magnetically levitated, and we carried out experiments using the one-degree of freedom model and continuous model for levitation control to determine the effect of a magnetic field from the horizontal direction applied to the levitated steel plate on its elastic vibration.

Keywords: Electromagnetic levitation control, thin steel plate, magnetic field, transportation

DOI: 10.3233/JAE-171147

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-8, 2019

Authors: Qian, Junbing | Bao, Liping | Ji, Chuankun | Wu, Jing

Article Type: Research Article

Abstract: A permanent magnet synchronous linear motor (PMSLM) is a linear drive mechanism that converts electric energy into mechanical energy. PMLSMs have been deployed widely in modern precision industrial manufacturing. In this study, an air-gap magnetic field model of a rectangular permanent magnet array in a PMSLM is developed based on the Biol-Savart theorem and the molecular circulation model. Furthermore, an analytical expression for the magnetic field distribution of the air-gap space is derived. Ansoft and experimental measurement are used to model the PMSLM and calculate the magnetic induction intensity and validate the analytical model. The relation between the air-gap magnetic field …of a PMSLM and the geometrical dimension of the permanent magnet is analyzed. Show more

Keywords: Permanent magnet synchronous linear motor, permanent magnet, magnetic field analysis, air gap, magnetic induction intensity

DOI: 10.3233/JAE-170162

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-13, 2018

Authors: Takei, Amane | Mizuma, Takeihito | Akatsuka, Motoki | Yamada, Tomonori

Article Type: Research Article

Abstract: This paper describes a method for evaluating the performance of electrical insulators exposed to winter environments using a large-scale numerical electrostatic analysis. Generally speaking, it is acknowledged that the presence of saltwater or accreted saline ice will degrade the ability of insulators to prevent electrical conduction. In our study, we began by confirming the insulation efficiency of insulators by conducting 50% impulse flashover voltage tests. Next, in order to study the performance of our evaluation method, the insulators were modeled via a parallel electrostatic analysis based on the hierarchical domain decomposition method. The mechanism for the deterioration of the insulation …performance was clarified with the proposed method. Show more

Keywords: Electrostatic analysis, ice accreted insulators, insulation performance evaluation, adventure system

DOI: 10.3233/JAE-170168

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-20, 2018

Authors: Hui, Sun | Chunni, Fang | Long, Zhang | Gongxian, Wang

Article Type: Research Article

Abstract: This paper presents a new design of cycloid corrugated magnetorheological fluid (MR) coupling based on the magnetorheological shear-pressure mixing mode. The device optimizes the formation of the magnetic chain through an arcuate magnetically conductive surface and guides the magnetic circuit with a magnetic isolation ring, so that the mechanical characteristics of the magnetorheological fluid can be fully utilized to enhance the power torque transmission capability. After describing the structure, electromagnetic simulations were performed to verify the formation of magnetically sensitive lines on an arc-shaped surface. The metal rolling force calculation method based on Orowan unit pressure differential equation was used …to establish a mechanical mechanism model of a magnetorheological fluid coupling with cycloid corrugated surface. The key parameters affecting the torque transfer performance of the MR coupling were calculated through Matlab software, and the performance of the device was evaluated. After that, the experimental platform was set up to test its performance. The experiment results indicate that the proposed MR coupling performs better than the conventional MR coupling with conventional planes in terms of torque output capability, transmission stability, and impact resistance, while maintaining a feasible magnetic circuit design and a compact structure. Show more

Keywords: Magnetorheological fluid, coupling, cycloid, electromagnetic simulation, mechanism model

DOI: 10.3233/JAE-180045

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-24, 2018

Authors: Ma, Xiaoping | Su, Sanqing | Wang, Wei | Yang, Yiyi | Yi, Shuchun | Zhao, Xuran

Article Type: Research Article

Abstract: Torsion tests on 50 Mn steel wire were implemented and illustrated in this research to probe into the relationship between normal components of self-magnetic-flux-leakage (SMFL) signals H p (y ) and early damage of steel wire subjected to torsional stress. Besides, a modified model with due consideration of coercivity and permeability varying with equivalent stress at elastic-plastic stage was presented to simulate H p (y ) signals of steel wire under torsion accurately. Relevant numerical simulations of magneto-mechanical coupling were performed. The results show that using zero crossing point (ZCP) of H p (y ) signals to …identify defect location does not apply to steel wire under torsion. However, there is crest (or trough) showing on magnetic signal curve prior to fracture. By utilizing location of crest (or trough), damage could be positioned accurately and ultimate fracture point could be forecasted in advance as well. Furthermore, simulation results obtained from the modified model are consistent with test results. Not only can study results demonstrate that MMM technique could be used for determining early damage of steel wire under torsion, but also provide certain reference for quantitative analysis about the relationship between damage and H p (y ) signals. Show more

Keywords: Steel wire, torsion, magnetic memory method, damage location, magneto-mechanical coupling

DOI: 10.3233/JAE-180075

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-24, 2018

Authors: Zhang, Guangwei | Yamamoto, Akio

Article Type: Research Article

Abstract: This work proposes a self-sensing method for a synchronous electrostatic film motor. The method utilizes the relation between the driving voltages and currents of the motor. Through several signal conversions on the measured motor currents, the system distills the information of the slider position to realize displacement sensing. The resulting system can track the slider position both for synchronous and non-synchronous operations. The system assumes stepwise motions of the slider and fully exploits the characteristic current features of the motions. Two different signal conversion methods have been tested using numerically simulated motor currents and real motor currents. The two methods …differ in terms of accuracy and noise immunity. Considering that the currents of the electrostatic motor are relatively small, the method with high noise immunity and relatively low accuracy was found useful for practical applications. The position resolution achieved by the method was in the order of the electrode pitch, which is 200 μm in the prototype motor used in this work. Show more

Keywords: Electrostatic film motor, displacement estimation, sensorless

DOI: 10.3233/JAE-180068

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-15, 2018

Authors: Tian, Lisi | Cao, Xiaoguang | Lv, Lankun | Wang, Haokun | Yu, Qiang

Article Type: Research Article

Abstract: Compared with L-and LC-filter, the LCL-filter attracts more and more research interests for its excellent harmonic suppression ability. However, the resonance peak of the LCL-filter may introduce potentially unstable dynamics that need to be carefully damped. Considering the PWM discrete nature and practical implementation in discrete form, to analysis the overall system stability is complex especially when considering the controller and the LCL-filter active damping as a whole system. Moreover different sampling frequency and different delay time that are specific in discrete domain influence the system stability scenario, which increase the analysis complexity. Different from the low order filter, LCL-filter …offers two kinds of possible current feedback, which presents totally different impact on overall system stability. In this paper, the stability of the overall system in discrete domain with two kinds of possible current feedback is investigated in detail. Three typical sampling frequency: high sampling frequency, medium sampling frequency and low sampling frequency are considered. And three typical delay time of active damping control: 0, T s ∕2, T s are introduced into stability analysis process. Experimental results get from a 3 kW laboratory prototype based on the TMS320F2808 are provided to validate the theoretical analysis presented in this paper. Show more

Keywords: Stability analysis, active damping, delay time, discrete domain, LCL-filter

DOI: 10.3233/JAE-180066

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-18, 2018

Authors: Shi, Tingna | Zhang, Yangshengmei | Guo, Liyan | Wang, Huimin | Xia, Changliang

Article Type: Research Article

Abstract: Interior permanent magnet machine has been widely used in electric vehicles due to its high-power density and good flux weakening performance. This paper firstly introduces the principle of flux-weakening control, which are the foundation to describe the effect of d -axis inductance and q -axis inductance on the speed range of motor. Secondly, regarding an interior permanent magnet synchronous motor with V -type permanent magnet structure as the research object, an improved rotor structure has been proposed which concludes asymmetric segmentations of permanent magnets and protuberances from centers of every magnetic poles toward airgap. Furthermore, the Taguchi method is …utilized to optimize the proposed improved structure. Finally, the optimized rotor structure which meet the requirement of d -axis inductance, q -axis inductance and electromagnetic torque has been obtained. Compared with the initial structure, the optimized rotor structure can increase d -axis inductance effectively, and hence broaden the speed range with constant power operation. Show more

Keywords: Speed range, interior permanent magnet synchronous machine, inductance, Taguchi method

DOI: 10.3233/JAE-180090

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-17, 2018

Authors: Rauf, Muhammad | Khan, Abid Muhammad | Ansari, Adeel | Jilani, Muhammad Taha | Shahzeb, Taha

Article Type: Research Article

Abstract: Marine controlled-source electromagnetic method (MCSEM) for seabed logging (SBL) uses a dipole source to generate low-frequency signals, and arrays of receivers to map the potential presence of hydrocarbon reservoirs. The characteristic depth of signal penetration in the subsurface, termed as skin depth, is one of the key parameters. However, the electromagnetic response by the resistive target in contrast to the skin depth evaluation has been less thoroughly documented. In this paper, a lab scale testing is performed to generate a data set with precisely scaled dimensions. The purpose is to verify the skin depth phenomenon in complex stratified mediums for …hydrocarbon detection. The synthetic electromagnetic data is produced using 1D modeling to validate the experimental results. The calculated correlation coefficient (CC) of more than 0.9 showed a good agreement between experimental and synthetic response. This outcome reveals that the depth of hydrocarbon detection does not solely depend on the skin depth of the applied frequency. The validated results recommend that a broadband electromagnetic transmitting system may reveal more authentic information about the hydrocarbon presence and extent of the hydrocarbon prospects. Show more

Keywords: Controlled-source electromagnetic methods, skin depth, electrode-based transmitter, 1D forward modeling, electromagnetic simulation

DOI: 10.3233/JAE-180105

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-16, 2018

Authors: Xu, Junqi | Chen, Chen | Sun, Yougang | Ji, Wen | Lin, Guobin

Article Type: Research Article

Abstract: When the maglev train is running on the guideway, the coupling effect between the vehicle and the guideway will inevitably cause vibration. Especially when the guideway is flexible, the vibration of the vehicle will cause slight deformation of the guideway, which may cause resonance. The irregularity of guideway geometry is the main source of excitation for vehicle random vibration. On the premise that the guideway irregularities cannot be eliminated objectively and thoroughly. In order to analyze its vertical random vibration, the vehicle adopts the two stage suspension model, the guideway adopts the Euler–Bernoulli simple supported beam model, and the random …irregularity of the guideway itself is used as the vibration source to control. At present, the power spectrum method based on random vibration theory is generally regarded as the most reasonable method, but the computational efficiency problem brought by this method has always been the bottleneck of random vibration analysis. Therefore, from the point of view of computational mechanics, the pseudo excitation method (PEM) is used to simplify the calculation of random vibration and to calculate random vibration. The coupled motion equations of the maglev vehicle under random excitation are obtained, and the computational efficiency is greatly improved. In addition, the vehicle suspension state is simulated at different operating speeds, and the effect of feedback control parameters on the stability of the magnetic levitation system is proved by numerical simulation. Finally, the influence of random excitation on vehicle guideway coupling vibration and the reliability of levitation control performance under random excitation are verified by experiments. Show more

Keywords: Maglev system, random irregularity, the pseudo excitation method, dynamic characteristics, coupled vibration

DOI: 10.3233/JAE-180051

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-18, 2018

Authors: Yang, Xiaolong | Hao, Fuxiang | Xu, Wubin | Gao, Shanghan | Chen, Fan | Sun, Peng | Li, Decai

Article Type: Research Article

Abstract: The diverging stepped magnetic fluid seal based on stepped labyrinth seal was an effective method to improve the capability of usual magnetic fluid seal with large gap. Pressure theory of the diverging stepped magnetic fluid seal was presented and a diverging magnetic fluid sealing with two magnetic sources was designed. The leakage location hypothesis in the diverging stepped magnetic fluid seal has been made. The magnetic field distributions in the radial and axial sealing gaps have been calculated by means of the finite element method of magnetic field and its maximum sealing capabilities have been calculated based on its pressure …theory. The effects of radial and axial sealing gaps on the diverging stepped magnetic fluid seal have been obtained. The numerical and experimental results were analyzed and discussed. The results show that the theoretical pressure-resistant capabilities of the diverging stepped magnetic fluid seal with two magnetic sources agree well with its experimental pressure-resistant capabilities. The leakage path in the axial sealing gap located at its center position and the leakage path in the radial sealing gap located in the vicinity of the shaft. Show more

Keywords: Large gap, magnetic fluid, numerical simulation, seal, stepped shaft

DOI: 10.3233/JAE-180097

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-10, 2018

Authors: Li, Xiangchao | Wan, Zhicheng | Liu, Yinping | Ma, Xiaoqi | Cai, Lujin | Xu, Xiaopei

Article Type: Research Article

Abstract: In order to study the problem of damage that caused by lightning overvoltage to the transistor, we designed the experiments of combined wave impact on the transistor under different conditions by analyzing the theory of the secondary breakdown of the transistor caused by the lightning electromagnetic pulse. These cases are carried out under the condition of no protection, transient protection diode (TVS) parallel protection, and TVS tube parallel protection in the actual base amplifier circuit. It is concluded that transistor can cause it to further deteriorate under the condition of lightning overvoltage impact, and the situation of the damage can …be divided into two categories, transient suppression diode in parallel with a transistor that is struck by a lightning voltage can effectively protect the transistor, which can obviously improve the resistance of the transistor. In practical amplifying circuit, applied voltage reduces the tolerance level of transistors, however, the tolerance level of transistors with transient suppression diodes in parallel is still better than the tolerance level without protection, which confirmed the conjecture that transient suppression diodes can be applied to actual circuits to protect transistors in parallel. In this paper, the theoretical analysis and experimental research on the damage of the lightning voltage on the transistor, the tolerance level of the transistor to the lightning voltage and the protection effect of the TVS tube on the transistor are carried out, which has certain reference value in the actual lightning protection of the transistor. Show more

Keywords: Crystal triode, lightning overvoltage, secondary breakdown, transient suppression diode

DOI: 10.3233/JAE-180092

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-12, 2018

Authors: Bu, Wenshao | Li, Biao | He, Fangzhou | Li, Jinwei

Article Type: Research Article

Abstract: Bearingless induction motor (BLIM), is a nonlinear, multivariable and strongly coupled object. In order to improve its dynamic decoupling control performance, and overcome the influences of the load disturbance and the motor parameter variation, under the conditions of considering the stator current dynamics of the torque system, the inverse system model of BLIM system is established firstly, and by the inverse system method, the BLIM system is decoupled into four second-order pseudo linear subsystems. And then, according to the sliding mode control (SMC) theory, the SMC regulator is designed for each subsystem, an exponential approach law is used to reduce …the chattering of SMC system; the stability of SMC system is verified by the Lyapunov method. Simulation experimental results have shown that the inverse system decoupling SMC system not only has an excellent dynamic decoupling control performance, but also has a faster response speed and a stronger robustness. Show more

Keywords: Bearingless induction motor, current dynamics, inverse system decoupling, sliding mode control, anti disturbance ability

DOI: 10.3233/JAE-180094

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-16, 2018

Authors: Wang, Tao | Zhang, Yunce | Ji, Daxiong

Article Type: Research Article

Abstract: This paper studies thermal modeling and parameter determination for a permanent magnet generator with built-in hydrostatic drive, which has some special thermal characteristics including being cooled by circulating hydraulic oil and being filled with leaked hydraulic oil. To predict its temperature, a thermal model is developed by analyzing thermal sources and heat transfer paths and reasonably simplified based on empirical analysis. Then system identification is implemented to determine the model’s main parameters such as thermal resistances and thermal capacitances. The variations of heat transfer coefficients due to rotational speed and oil viscosity are taken into consideration through theoretical correction. Finally, …comparisons between calculated results and experimental results under different load conditions are presented to verify the effectiveness of the thermal model. The effects of ambient temperature and input oil temperature on the temperature rise are also investigated based on the model. This study can also provide reference to the temperature estimation of those similar machines filled with liquid. Show more

Keywords: Heat transfer, parameter estimation, permanent magnet generators, thermal model

DOI: 10.3233/JAE-180005

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-15, 2018

Authors: Zhao, Jianhui | Yue, Pengfei | Grekhov, Leonid | Wei, Kebiao | Ma, Xiuzhen

Article Type: Research Article

Abstract: In our study, the B–H magnetization curves at temperatures between 16 and 150 ∘ C and frequencies between 50 Hz and 1000 Hz were measured to analyse the effect of temperature and frequency on the magnetization characteristics of electrical iron DT4C. By researching a high-speed solenoid valve (HSV) for a common rail injector, the temperature and frequency dependence of DT4C and their effects on the electromagnetic force and dynamic response of a HSV were obtained. The research results showed that an increase in temperature could decrease the magnetic flux density; however, the decrease was …not apparent. The effect of temperature on the relative permeability depended on the range of magnetic flux density B . The temperature dependence of DT4C was weak in the temperature range of 16--150 ∘ C . This stability of magnetic characteristic of DT4C ensures that the dynamic response of a HSV could be maintained well for a common rail injector. Magnetization frequencies had a significant influence on the magnetization of DT4C. An increase in the frequency would delay the transition to the saturation magnetic flux density Bs . The effect of frequency on the electromagnetic force became increasingly significant as the driving current increased. In a frequency range of 50–200 Hz, the opening response time of a HSV could be maintained well. When the frequency was higher than 200 Hz, the opening time increased significantly with the frequency raised from 200 Hz to 1000 Hz, furthermore, the HSV was out of control and closed ahead of time. Show more

Keywords: Dynamic response, magnetic B-H curve, high speed solenoid valve, common rail injector

DOI: 10.3233/JAE-180022

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-15, 2018

Authors: Park, Eui-Jong | Gim, Chan-Seung | Jung, Sang-Yong | Kim, Yong-Jae

Article Type: Research Article

Abstract: A magnetic gear, which can transfer torque without contact, has many advantages over mechanical gears. These advantages include high-efficiency and high-reliability. Consequently, the magnetic gear is utilized in many different fields of study. However, because the magnetic gear uses NdFeB permanent magnets (PMs) for high power density, eddy-current loss can occur. Eddy-current loss is very problematic because it is the main factor that reduces torque transfer efficiency. Therefore, in the present study, we calculated the eddy-current loss from PMs at different rotational velocities by using a nonlinear finite element method (FEM) based on a three-dimensional numerical analysis, and analyzed how …the eddy-current loss affects the torque transfer efficiency. Furthermore, we proposed a new geometry for the magnetic gear to reduce the eddy-current loss of PMs and improve the torque transfer efficiency. Show more

Keywords: Magnetic gear, permanent magnet (PM), eddy-current loss, torque transfer efficiency, finite element method (FEM)

DOI: 10.3233/JAE-180055

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-10, 2018

Authors: Li, Xiangchao | Cai, Lujin | Xu, Xiaopei | Wan, Zhicheng | Ma, Xiaoqi | Liu, Yinping

Article Type: Research Article

Abstract: Corona plays an important role in both initiation and development process of leaders around wind turbine blades. In this paper, based on laboratory experiments and numerical simulation, the corona triggering tests are performed by analyzing corona discharge characteristics of wind turbine blades. The corona threshold voltage and the corona current are measured. The corona environmental threshold and the corona triggering threshold are evaluated and discussed in detail. The influence of blade lengths, rotational angles and rotational speeds is analyzed. The results show that the corona trigger threshold obtained is a constant and is about 321.29 kV/m, which appears to be some fluctuations due …to atmospheric conditions and charged ions. In addition, through analysis the corona triggering threshold of different rotational angles and the corona environmental threshold of different rotational speeds, rotational wind turbine blades affect the electric field near the blades by varying the blade height and the charged ions distribution at the tip of the blades where the altered blade height accounts for the dominant factor. The above research results are valuable for the understanding of the initiation and development of leaders around the wind turbine blades. Show more

Keywords: Wind turbine blades, electric field distortion, corona discharge, corona triggering threshold, corona environmental threshold

DOI: 10.3233/JAE-180085

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-11, 2018

Authors: van der Horst, Menno Patrick | van Kreveld, Sylvia Lyanne | Kaminski, Miroslaw Lech

Article Type: Research Article

Abstract: Wireless crack monitoring on ships and offshore structures based on Self Magnetic Flux Leakage (SMFL) measurements is a promising method to guarantee the structural integrity in a more effective way, leading to reduced operational costs and increased safety. For accurate crack sizing, the SMFL measurements must be interpreted correctly, also during cyclic loading. Not much research has been done that focus on the effect of high cyclic stresses on the magnetization of ferromagnetic steels in weak magnetic fields. The aim of the research presented in this paper is to investigate the effect of stress-induced magnetization on the SMFL in the …stress concentration zone of a structural steel plate, and its implications for crack monitoring by the SMFL method. By means of an experiment, measured stress magnetization curves were obtained in a grid of points around an elliptical hole in a steel plate that was cyclically loaded up to the yield stress. The results show that the stress-induced magnetization causes a maximum variation of the measured signal of 25 μT, which is fully reversible. It is concluded that, depending on the application, this stress-induced variation may need to be taken into account for the interpretation of the measured signals by a crack monitoring system using the SMFL method. Show more

Keywords: Crack monitoring, self magnetic flux leakage, stress magnetization, ferromagnetic steel, cyclic loading

DOI: 10.3233/JAE-180031

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-18, 2018

Authors: Qiu, Li | Yu, Yijie | Li, Tao | Feng, Guang | Su, Pan | Chang, Peng | Deng, Changzheng | Xiong, Qi

Article Type: Research Article

Abstract: To improve the heating efficiency of the induction cooker system, this paper adopts the method of introducing an adiabatic layer between the pot bottom and the coil. By using COMSOL software, the electromagnetic - thermal coupling model of the induction cooker is established to analyze the effect of the adiabatic layer on the food temperature and coil temperature, and finally the heating efficiency is explored. The obtained simulation results show good agreements with the experimental results, and then the effectiveness of the proposed method is verified.

Keywords: Induction cooker, adiabatic layer, heating efficiency, electromagnetic - thermal coupling model

DOI: 10.3233/JAE-180072

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-10, 2018

Authors: Gandanegara, Grace | Rahmani, Mustapha | Gualino, David | Lechat-Sanjuan, Sylvain | Herriot, Yann | Guyon, Caroline Aubert | Dobrowolski, Jean | Dentella, Alain | Wang, Miao-Xin | Mazauric, Vincent

Article Type: Research Article

Abstract: Genset is usually used as the electricity generator and known for its stability thanks to its rotating inertia. With the population growth, the electricity demand is increased. Due to the limited amount of fossil energy resources and the climate-friendly issues, the renewable energy integration becomes higher. However, the intermittence of these resources can destabilize the grid. To integrate these renewable energies by behaving as genset with its rotating inertia, the Virtual Synchronous Machine concept is implemented in a microgrid.

Keywords: Virtual synchronous machine, microgrid, storage

DOI: 10.3233/JAE-171079

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-7, 2018

Authors: Tanaka, Yoshikazu | Koyama, Hiroaki | Odake, Satoru | Mutsuda, Hidemi | Popov, Atanas A. | Patel, Rupesh | McWilliam, Stewart

Article Type: Research Article

Abstract: In this paper, flexible piezoelectric devices (FPEDs) connected by springs are discussed with the aim of improving operational bandwidth of an energy harvesting system. A theoretical method, based on beam theory, electromechanical coupling and the transfer matrix method, is presented for calculating displacement and voltage responses. Validity of the presented method is discussed by comparison with experimental results, which are obtained from coupled FPEDs excited by a shaker. The effects on system behaviour of attaching springs is discussed based on both the presented method and experimental results.

Keywords: Piezoelectric film, flexible piezoelectric device, renewable energy, theoretical analysis method, forced vibration, engine vibration

DOI: 10.3233/JAE-171007

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-9, 2018

Authors: Vinsard, Gérard | Dufour, Stéphane

Article Type: Research Article

Abstract: A model to compute the forces between small and thin co-planar magnetic disks submitted to an uniform source magnetic field is built with the help of a pseudo magnetic dipole formula, in a similar way as the one used for beads. These forces are used to compute the motion of such disks floating on the top of a viscous liquid. Numerical results are compared to experimental data: it shows a good qualitative accordance.

Keywords: Magnetic dipole, demagnetizing factor, magnetic disk

DOI: 10.3233/JAE-171009

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-6, 2018

Authors: Mazauric, Vincent

Article Type: Editorial

DOI: 10.3233/JAE-171114

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-2, 2018

Authors: Wang, Cheng | Huang, Haiyang | Zhang, Tianshu | Chen, Yewang | Zhang, Yiwen

Article Type: Research Article

Abstract: To address the problems of singularities, sensitivity to measurement noise, and low efficiency in traditional principal component analysis (PCA)-based operational modal analysis (OMA), we present a Sanger neural network principal component analysis (SNNPCA) algorithm to identify the operational modal parameters. SNNPCA is a two-layer neural network that is trained using a generalized Hebbian algorithm to ensure that its output converges to the principal components. After SNNPCA has converged, the link weights of SNNPCA correspond to the separation matrix of PCA. In SNNPCA-based OMA, the measurement response points are set as the input neurons, modal coordinate response signals are set as …the output neurons, and the link weights of the neural network represent the modal shapes. Therefore, the operational modal identification process in SNNPCA is physically meaningful and convergent. Furthermore, SNNPCA inherits the parallel nature of neural network algorithms, so it is also insensitive to measurement noise. Simulation results show that SNNPCA can identify the principal modal parameters accurately using only measurement response signals. This method can be applied in embedded devices to realize online monitoring and real-time fault diagnosis. Show more

Keywords: Operational modal analysis, principal component analysis, Sanger neural network, generalized Hebbian rule, parallel, measurement noise

DOI: 10.3233/JAE-171011

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-12, 2018

Authors: Vesa, Joonas | Karhula, Taru | Marjamäki, Antero | Panchal, Jay | Rasilo, Paavo

Article Type: Research Article

Abstract: In this paper we describe an algorithmic method to imitate geometries of soft magnetic composites. We use microscope images to determine some of the most important geometric characteristics of the material and optimize the algorithm such that the measured and simulated characteristics are in agreement. We compute the static magnetization curves using the geometries obtained from the images and the algorithm comparing the results. The aim is to produce realistic geometries to be used in homogenization schemes as well as to study the effects of magnetic contacts in general.

Keywords: Geometry generation, homogenization, magnetic composite

DOI: 10.3233/JAE-171032

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-8, 2018

Authors: Yoshioka, Saijiro | Marumoto, Tatsuya | Gotoh, Yuji

Article Type: Research Article

Abstract: The crude oil which flows inside the steel tube of a heating furnace of an oil-refining plant is gasified by being heated with the burner from the surface outside the steel tube. Since this steel tube is used in Japan for 30 years or more, both the inner side and outer side of the steel tube is carburized. If the carburization depth is increased, the steel tube will be exploded suddenly and a big accident may occur. In this paper, the electromagnetic inspection method for measuring the carburized depth of both the inner side and the outer side of the …steel tube is proposed. The both depth is obtained by evaluating the flux density in layers with and without carburization in the steel tube using the 3-D nonlinear FEM. It is shown that the inspection for the both depth is possible by using the differential electromagnetic characteristics of the layers with and without carburization in the steel tube. Show more

Keywords: Electromagnetic non-destructive inspection, carburization steel tube, both surface and opposite side depth, 3-D finite element method

DOI: 10.3233/JAE-171112

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-8, 2018

Authors: Chevillard, Sylvain | Leblond, Juliette | Mavreas, Konstantinos

Article Type: Research Article

Abstract: We consider the inverse problem of recovering the position and moment of a magnetic dipole from sparse measurements of the field it generates, known on sections of three orthogonal cylinders enclosing it. This problem is motivated by recent measurements performed on Moon rocks, in view of determining their magnetic properties. The key ingredient of the presented method is the use of rational approximation techniques, together with properties of the poles of the approximants, in order to estimate the position of the dipole.

Keywords: Inverse problems, magnetic dipole, source estimation, rational approximation, Moon rocks

DOI: 10.3233/JAE-171033

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-7, 2018

Authors: Dhahbi, Hakim | Gallot-Lavallee, Olivier | Kedous-Lebouc, Afef | Mas, Patrick | Geoffroy, Olivier | Buffat, Sebastien

Article Type: Research Article

Abstract: In this paper, the magnetic losses of a supply current sensor dedicated to circuit breakers are investigated. Measurements were performed using an accurate calorimeter covering a measurement range of [1 mW; 10 W]. Several frequencies and voltages were tested. A model of the sensor’s core material (NO SiFe sheet M250-50A) was built with the Loss Surface (LS) dynamic hysteresis model and implemented in a 3D FEM computation tool. The sensor was simulated and iron losses were computed. Comparison between experiments and simulation shows a high concordance that leads to conclude about the reliability of the LS model.

Keywords: Iron losses, current sensor, Silicon Iron magnetic steel, circuit breaker, modelling and experiment, Epstein bench

DOI: 10.3233/JAE-171022

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-10, 2018

Authors: Uoshita, Shoya | Sasaki, Kota | Katagiri, Takuya | Yusa, Noritaka | Hashizume, Hidetoshi

Article Type: Research Article

Abstract: This study evaluated the effect of bends on the long-range nondestructive testing inspection of pipe surfaces based on microwaves propagating inside the pipe. Three-dimensional finite element simulations were conducted to reveal electromagnetic fields at bends with a diameter of 23 mm and various radii of curvature when microwaves were emitted into a pipe in the TM01 mode that had been mainly used in earlier studies. The simulations revealed that the effect of the bend on the microwaves is not significant when the ratio of curvature is larger than approximately 2, whereas in general a bend reflects a part of microwaves …and causes non-TM01 modes. Subsequent experimental verifications, which used a pipe with a total length of approximately 4 m and a 90-degree or 180-degree bend, confirmed clear reflections due to artificial wall thinning in spite of the presence of the bend. Show more

Keywords: Electromagnetic nondestructive evaluation, wall thinning, pipe degradation, time of flight, electromagnetic wave, finite element simulation

DOI: 10.3233/JAE-171001

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-8, 2018

Authors: Liedtke, Lukas | Gueltig, Marcel | Kohl, Manfred

Article Type: Research Article

Abstract: A miniature-scale device for harvesting of vibrational energy is presented, which is based on the inverse magnetic shape memory effect caused by stress-induced reorientation of magnetic moments. The active material is a bulk NiMnGa sample of 1 mm × 2.5 mm × 4.5 mm. A new harvester design is developed consisting of a moving magnetic circuit of mass M mounted on a spring to convert external vibrations to the active material. Thus, the deformation of the NiMnGa sample can be adjusted by tailoring the design parameters (mass M , sample dimensions, spring constant, etc.) for a given vibration source. The design and …performance of first prototypes are presented showing an output power of 1.5 μW during a single load cycle at an optimum biasing magnetic field of 0.35 T. Show more

Keywords: xxx

DOI: 10.3233/JAE-171038

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-7, 2018

Authors: Nakai, Tomoo

Article Type: Research Article

Abstract: A thin-film magneto-impedance (MI) sensor has the unique property of step-like magneto-impedance change, in the case where the sensor has an in-plane uniaxial inclined easy axis. A domain observation shows that the step-like change is due to a magnetization transition within three states, such as longitudinal single domain with parallel state, the one with anti-parallel state and the inclined Landau-Lifshitz domain (ILLD). In a condition where the sensor has an easy axis of 70 degrees relative to the short side axis of the rectangular element, the transition is limited between the parallel and anti-parallel in spite of existing of stable …ILLD. This paper reports a trial of control the magnetization transition from the single domain state to the ILLD state by controlling a normal field with canted angle distribution along the element position, which is aiming for realizing a low energy consumption sensor with inextinguishable memory function using a phenomenon of a magnetic domain transition for the use of sensor network. Show more

Keywords: Magnetic domain, magneto-impedance, normal field, stepped GMI, thin film

DOI: 10.3233/JAE-171005

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-10, 2018

Authors: Li, Yong | Wang, Yi | Yan, Bei | Cai, Rui | Chen, Zhenmao | Abidin, Ilham Mukriz Zainal | Jing, Haoqing

Article Type: Research Article

Abstract: In-service tubular conductors are prone to such anomalies as the wall-thinning defect and hidden corrosion which pose a severe threat to structural integrity. In this paper, a capsule-typed electromagnetic acoustic transducer is proposed for inspection of tubular conductors such as small-diameter pipes subject to external corrosion. An efficient hybrid model of Electromagnetic Acoustic Transduction (EMAT) is established in an effort to reveal the underlying physical phenomena and simulate the resulting responses to external wall-thinning defects in tubular conductors. The model integrates a fast analytical model computing the electromagnetic field and resulting Lorentz force with Finite Element Modeling (FEM) for simulation …of ultrasonic field. The established model is corroborated via FEM and experiments, and beneficial to the optimization of the proposed capsule-typed electromagnetic acoustic transducer for non-destructive evaluation of tubular conductors. Show more

Keywords: Electromagnetic non-destructive evaluation, electromagnetic acoustic transduction, tubular conductor, analytical modeling, hybrid model

DOI: 10.3233/JAE-171006

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-9, 2018

Authors: Su, Zhiyi | Rosell, Anders | Ye, Chaofeng | Udpa, Lalita | Udpa, Satish S. | Tamburrino, Antonello

Article Type: Research Article

Abstract: Eddy current methods are commonly used in the inspection of riveted multilayer structures. In a practical scenario, steel rivets may be magnetized to varying levels which can distort the magnetic field and pose a major challenge since the distortion can result in false positives and negatives. This paper presents an invariance transformation procedure that renders the signal insensitive to changes in magnetization while retaining the sensitivity to defect information. The approach is first implemented on simulated data, where the signals from magnetized steel rivets can be generated under controlled variation of relative permeability. The algorithm is then validated on experimental …data acquired using steel rivets with different residual magnetization levels. Show more

Keywords: Nondestructive evaluation, eddy current, magnetoresistance, invariance transformation

DOI: 10.3233/JAE-171037

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-8, 2018

Authors: Ishikawa, Takeo | Watanabe, Taiki | Suzuki, Yuichiro

Article Type: Research Article

Abstract: The authors designed a rotor structure of permanent magnet synchronous machine (PMSM) to develop a large output power by the proposed topology optimization method. As the obtained magnet shape is complex and less practical, this paper proposes a rotor topology of PMSM considering ease of manufacturing. Finite element simulation confirms that the average output power of the designed machine is higher than that of a generator used in Prius under the condition of the same stator, the same weight of rotor and the same permanent magnet volume.

Keywords: Topology optimization, permanent magnet synchronous machine, asymmetrical rotor

DOI: 10.3233/JAE-171030

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-8, 2018

Authors: Ustun, Ozgur | Kara, Duygu Bayram

Article Type: Research Article

Abstract: In this paper, an electromagnetic analysis study of a double-sided linear motor topology is conducted both for conventional and Halbach array magnet assemblies. Halbach arrays can condense flux lines on the one side of magnet assembly and cancel them on the reverse side, so they enable light motor structures due to the lack of back iron material. By means of the analyses, the critical performance criteria of linear motor are investigated. The designs are verified experimentally. The induced voltages and force production of prototype motors are captured to validate the design study. The findings show that Halbach array magnet assembly …type linear motor has superiority for force production and lightness of design. Show more

Keywords: Linear coreless motor, double-sided linear motor, PM motor, Halbach array

DOI: 10.3233/JAE-171035

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-7, 2018

Authors: Kim, Sung-An | Park, Soo-Keun | Cho, Yun-Hyun

Article Type: Research Article

Abstract: This paper presents the cost reduction design of a brushless DC motor (BLDCM) considering twelve step control. The twelve step control can improve the output of the motor using the conventional six step control. Weight reduction can be effectively achieved by reducing rotor, stator and magnet through optimization of BLDCM using a response surface method (RSM). The BLDCM volume was decreased by about 45%, while satisfying basic performance requirements and improving efficiency. Original and optimized motors were built and tested. Experimental results are compared in terms of output power and efficiency.

Keywords: Brushless DC motor, sensorless control, twelve step, response surface method, finite element method analysis

DOI: 10.3233/JAE-171002

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-8, 2018