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

Authors: Zheng, Li | Qing, Chen | Yu, Xiao | Dixin, Wang | Leiyong, Wang | Qunjing, Wang

Article Type: Correction

DOI: 10.3233/JAE-189064

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

Authors: Kim, Hong-seok | Kwon, Jung-woo | Kwon, Byung-il

Article Type: Correction

DOI: 10.3233/JAE-191919

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

Authors: Chen, Yuanyang | Bao, Xiaohua | Gao, Ge | Tang, Yizhui

Article Type: Research Article

Abstract: This paper studies the impact of Poloidal Field (PF) coil current disturbance on plasma shape in Experimental Advanced Superconductive Tokamak (EAST). First, the concept of the free-boundary equilibrium problem is studied. Based on the non-rigid plasma model, a free-boundary equilibrium solver developed in MATLAB software is presented to calculate the flux distribution and plasma profile of EAST plasma equilibrium, and the results are validated against the experiments. Second, given a typical double-null plasma equilibrium, the responses of plasma shape to the lower PF coil currents are computed using the orthogonal test method. The dependences of the elongation and triangularity of …plasma shape on PF coil currents are obtained, showing that the currents in PF6 and PF8 have the greatest impact on triangularity and elongation for lower single-null (LSN) divertor configuration, respectively. And for double-null (DN) divertor plasma configuration, PF5 and PF7 play equally important roles due to the up-down symmetry. The conclusions will be useful for the design of EAST plasma shape feedback control. Show more

Keywords: EAST tokamak, plasma shape response, free-boundary equilibrium calculation, orthogonal test method

DOI: 10.3233/JAE-180133

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-9, 2019

Authors: Fenercioğlu, Tevfik Ozan | Yalçinkaya, Tuncay

Article Type: Research Article

Abstract: As an integral part of Strapdown Inertial Navigation Systems, ring laser gyroscopes (RLG) are exposed to joint loading conditions where thermal, static and dynamic loads occur simultaneously. The effects of different loading conditions on overall RLG performance should be addressed in parallel for an optimum design. A crucial aspect in this process is the development of the path length controller (PLC), consisting of a mirror, a composite piezo electric bending actuator and other motion transfer elements. This study presents an analogy between the external loading (static, dynamic, thermal, and vibration) on PLC and the RLG signal stability, which has been …studied only partially in the open literature. 5 different PLC designs are analyzed through finite element method and the results are validated experimentally using the composite piezo electric bending actuator by mode-scanning and PZT feedback tests. Obtained results illustrate the axial and the radial displacement (also named mirror tilt) capacity of different PLC designs. Disruptive effects of radial displacement of the PLC mirrors on RLG signal stability are observed. The study is concluded with the classification of different PLC designs for distinctive loading conditions, which is believed to be valuable for the aerospace industry. Show more

Keywords: Path length controller, ring laser gyroscope, finite element analysis, optimization, laser stability, strapdown inertial navigation system

DOI: 10.3233/JAE-190019

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

Authors: Zhou, Dong | Wei, Min-Xiang | Shi, Li-Hua | Cao, Jie

Article Type: Research Article

Abstract: The mechanism of electromagnetic interference (EMI) is studied for an engine speed acquisition system in this paper. The effect of states and terminal loads is analyzed for the interference signal, which is simulated by using a commercial software. The oscillation of the voltage interference signal is produced by the speed sensor under the radiation of high-altitude nuclear electromagnetic pulse (HEMP), which has been validated by both simulation and experiment. The interference signal can be collected by the speed acquisition system and the normal operation of the engine will be obstructed. The GTEM cell is used for producing the plane wave …for the experiment and the speed acquisition controller is used to test the ability of acquisition for interference signals. Show more

Keywords: Speed acquisition, EMI, HEMP, speed sensor

DOI: 10.3233/JAE-180131

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

Authors: Huang, Lantao | Zhang, Jing | Zou, Jiahao | Zhou, Yihan | Qiu, Li

Article Type: Research Article

Abstract: Electromagnetic forming (EMF) technology uses pulsed current to generate a pulsed electromagnetic force on metal workpiece to accomplish plastic deformation. It is a promising solution for the room temperature processing of lightweight alloy. Coil design is important to energy efficiency and forming performance of EMF. In order to clarify the effect of the equivalent radius of the drive coil on the forming performance, a simulation study is conducted. The preliminary experiment results show good agreement with results of the simulation, and prove the reliability of the simulation model. Then the process of the electromagnetic sheet free bulging is simulated and …analyzed. It is found that the combined action of the boundary constraint and the inertia effect will influence the maximum forming depth. And the maximum values can be obtained at different systems when the ratio of the equivalent coil radius to the active workpiece radius is about 0.68. Show more

Keywords: Electromagnetic forming, coil design, the maximum forming depth

DOI: 10.3233/JAE-190009

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

Authors: Zhang, Yunfeng | Ren, Huan | Zhao, Chenlong | Chen, Jiawen

Article Type: Research Article

Abstract: The three-dimensional model of a lightning rod under a thunderstorm simulated by COMSOL Multiphysics software is established in this paper to study the influencing factors on electric field distortion including the position, height and shape of the lightning rod. In the model, the thunderstorm cloud is equivalent to a plate capacitor; and the building, the lightning rod and the ground are regarded as perfect conductors; whereas their surface potential is zero. The electric field distortion coefficient K is used to measure the influencing parameters on the lightning attachment to the lightning rod. The analysis of model leads to the following …conclusions: influenced by the electric field distortion, a lightning rod at a higher height or at the edge of the building is more likely stuck by the lightning. Considering the effects of the upward connecting leaders in the attachment process, we can further infer that the upward leaders usually start from the tip with greater distortion electric field in the attachment process. However, when the tip of the rod is too sharp, it is often accompanied by the fast attenuation of the electric field, which is not beneficial for the continuous development of the upward connecting leaders. Therefore, in the process of lightning protection design, it is necessary to consider both the position and the height, as well as the shape of the lightning rod in a comprehensive manner. Show more

Keywords: Lightning rod, electric field, distortion coefficient, attachment process

DOI: 10.3233/JAE-180091

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

Authors: He, Tianhu | Ma, Jintao | Li, Yan

Article Type: Research Article

Abstract: In present work, the transient responses of a hollow cylindrical conductor based on the generalized thermoelastic theory with memory-dependent derivative are investigated The conductor with temperature-dependent mechanical properties is subjected to a thermal shock on its internal surface. The hollow cylindrical conductor is placed in a magnetic field along the axial direction of the cylinder. The effects of memory-dependent derivative and temperature-dependent properties influenced by the variable material property factors on the heat conduction and structural responses are emphatically discussed. The coupled governing equations containing time delay factors and kernel functions, which can be chosen freely according to specific problems, …are solved by the Laplace transform together with its numerical inversion. The distributions of the non-dimensional induced electric field, induced magnetic field, hoop stress, radial stress, temperature and displacement at different values of time delay factors, kernel functions and variable material property factors are obtained and illustrated graphically. Finally, some conclusions are summed up, based upon which guidelines may be provided in the design of a hollow cylindrical conductor working in a thermo-mechanical coupling environment. Show more

Keywords: Memory-dependent derivative, hollow cylindrical conductor, induced electric field, induced magnetic field, Laplace transform

DOI: 10.3233/JAE-180124

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

Authors: Suzuki, Reiya | Okamoto, Yoshifumi | Wakao, Shinji

Article Type: Research Article

Abstract: Although rare earth materials are actively utilized in permanent magnets for a wide variety of applications including electric vehicles and trains, the cost of these materials is on the rise. Therefore, the synchronous reluctance motor (SynRM) which does not require permanent magnets is remarkable from the perspective of high efficiency and low cost. However, the torque characteristic of the SynRM is much lower than that of the interior permanent magnet synchronous reluctance motor (IPMSM). Then, a permanent magnet assisted synchronous reluctance motor (PMASynRM) which bonded magnet was attached to the rotor structure of SynRM has been proposed. The manufacturing cost …of the PMASynRM is lower than that of the IPMSM because a bounded magnet is utilized former. In this work, the structure of the PMASynRM has been drastically changed by topology optimization to average torque maximization and cogging torque minimization. Show more

Keywords: Average torque, cogging torque, Heaviside function, permanent magnet assisted synchronous reluctance motor, topology optimization

DOI: 10.3233/JAE-191115

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. s1-s9, 2019

Authors: Diampovesa, Sephora | Hubert, Arnaud | Yvars, Pierre-Alain | Meyer, Yann | Zimmer, Laurent

Article Type: Research Article

Abstract: In electrical engineering, current methods show limits when it comes to complex design problems with heterogeneous and multidisciplinary requirements in the preliminary steps. Also, the setting and the solving of those problems is a simultaneous challenge that needs to be more explored. It may be necessary to recall the need to re-think the conventional design process when it comes to complex electrical systems. Particularly, by considering first the problem admissibility before its solving or optimization. Being able to detect an ill-posed or an over-constrained problem (causal analysis) can help in finding admissible solutions but also forces the designers to understand …the meaning of the problem modeling. A synthesis point of view is proposed to ensure admissible and relevant solutions during the preliminary design (pre-design) process. Intervals and constraint-based methods are shown suitable for proposing efficient modeling, solving tools and addressing optimal design. This paper is illustrated by the case study of a benchmark transformer, taking into account multi-physical requirements. The optimal design includes mixed-type variables and tabulated constraints such as manufacturer datasheets. The computed results are then compared with solutions found in the literature and show the advantages of the implemented method in terms of solutions and computation time. Show more

Keywords: Optimal design, interval methods, constraints satisfaction problems, pre-design of electromagnetic devices

DOI: 10.3233/JAE-191104

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. s1-s14, 2019

Authors: Formisano, Alessandro | Martone, Raffaele

Article Type: Research Article

Abstract: The resolution of inverse problems is a quite common task in the diagnostic processes based on electromagnetic field measurements, in particular when internal characteristics of the object under test must be estimated from external measurements. This class of problems are well known to be ill posed, and a number of different regularization techniques have been proposed to make the estimation process reliable. In this paper, with reference to an application in the framework of low frequency magnetic fields measurements, a comparison of some regularization techniques is presented, in order to highlight advantages and drawbacks of each in the proposed application.

Keywords: Inverse problems, magnetic measurements, regularization, tolerance assessment

DOI: 10.3233/JAE-191105

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. s1-s14, 2019

Authors: Poline, Marie | Gerbaud, Laurent | Pouget, Julien | Chauvet, Frédéric | Castaing, Ali

Article Type: Research Article

Abstract: In France, most of the trains are electrical and some are fed by 1500 V DC voltage. When a train is traveling, the power consumption creates a voltage drop. Therefore, below a certain limit, the train has to slow down its speed. This limitation prevents the increase of traffic in some area that needs an electric reinforcement. This paper proposes to use embedded storage systems to support the voltage of the catenary. The main issue is how to size such an energy storage system? In this way, several aspects (e.g.: the energy management strategy) have to be taken into account. The …paper deals with an optimization-based sizing method for the embedded energy storage systems. The proposed method takes into account the energy management strategy in the sizing by optimization. A comparison is made between the use of batteries or supercapacitors. Show more

Keywords: Electric hybrid train, energy management, optimization, sizing, SQP

DOI: 10.3233/JAE-191112

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. s1-s16, 2019

Authors: Otomo, Yoshitsugu | Igarashi, Hajime

Article Type: Research Article

Abstract: This paper presents three-dimensional topology optimization of magnetic cores for wireless power transfer with double-sided winding coils. In this optimization, the magnetic core shape is represented by the linear combination of the normalized Gaussian functions. The core shape is optimized so that the coupling coefficient between the transmitting and receiving coils is maximized. Moreover, robustness against misalignment between the coils is taken into account in the optimization. It is found that the optimized core shape effectively increases the net magnetic flux interlinked with the receiving coil, and outperforms the conventional core shapes.

Keywords: Electric vehicle, genetic algorithm, robust optimization, topology optimization, wireless power transfer

DOI: 10.3233/JAE-191110

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. s1-s9, 2019

Authors: Di Barba, Paolo | Mognaschi, Maria Evelina | Rezaei, Najmeh | Lowther, David Alister | Rahman, Tanvir

Article Type: Research Article

Abstract: The main aim of this work is to determine the optimal shape design of a class of Interior Permanent-Magnet (IPM) motors for electric vehicles (EV), by means of many-objective optimisation which is an emerging area in the automated optimal design. As the case study, a 3-phase, 4-pole single-barrier IPM motor is modelled by means of using finite-element analysis. The goal is to optimise the motor’s performance in terms of a number of design criteria such as the power losses, running torque, torque ripple and material costs, by varying size and position of the permanent magnet and flux barriers.

Keywords: Finite-element analysis, interior permanent-magnet motor, many-objective optimisation, optimal shape design

DOI: 10.3233/JAE-191113

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. s1-s14, 2019

Authors: Alnajjar, Belal M.K. | Buchau, André | Anders, Jens | Blümich, Bernhard

Article Type: Research Article

Abstract: An H-shaped low-field permanent magnet is presented. It has been designed, simulated and optimized using the finite element method. The magnet mainly consists of two poles, each of which consists of 37 hexagonal magnetic blocks that are magnetically connected by an iron yoke. To achieve the magnetic field homogeneity in the ppm range required for NMR applications, mechanical shimming by a vertical adjustment of the hexagonal magnetic blocks has been applied. Here, the displacement of each block from the initial equidistant symmetric design has been optimized by applying a pattern search method. In addition, two pole pieces made of iron …have been added to the magnet to further improve the magnetic field homogeneity. The dimensions of these pole pieces have been optimized using a genetic algorithm. The magnetic field homogeneity of 15 ppm (parts per million) measured inside the manufactured prototype verifies the accuracy of the proposed simulation based design approach. Show more

Keywords: Finite element methods, genetic algorithms, mobile NMR, NMR magnet, permanent magnet design, pattern search algorithms, shimming

DOI: 10.3233/JAE-191101

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. s1-s12, 2019

Authors: Haltmeier, Markus | Zangerl, Gerhard | Schier, Peter | Baumgarten, Daniel

Article Type: Research Article

Abstract: Magnetorelaxometry imaging is a novel tool for quantitative determination of the spatial distribution of magnetic nanoparticle inside an organism. The use of multiple excitation patterns has been demonstrated to significantly improve spatial resolution. However, increasing the number of excitation patterns is considerably more time consuming, because several sequential measurements have to be performed. In this paper, we use compressed sensing in combination with sparse recovery to reduce the total measurement time and to improve spatial resolution. For image reconstruction, we propose using the Douglas-Rachford splitting algorithm applied to the sparse Tikhonov functional including a positivity constraint. Our numerical experiments …demonstrate that the resulting algorithm is capable to accurately recover the magnetic nanoparticle distribution from a small number of activation patterns. For example, our algorithm applied with 10 activations yields half the reconstruction error of quadratic Tikhonov regularization applied with 50 activations, for a tumor-like phantom. Show more

Keywords: Compressed sensing, magnetorelaxometry, image reconstruction, magnetic nanoparticles, multiple excitation, Douglas-Rachford splitting, sparse recovery

DOI: 10.3233/JAE-191106

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. s1-s16, 2019

Authors: Le Luong, H.T. | Messine, F. | Hénaux, C. | Bueno Mariani, G. | Voyer, N. | Mollov, S.

Article Type: Research Article

Abstract: Numerical optimization algorithms based on finite element analysis are widely used to design electrical machines, especially with complex geometries. The advantage of these approaches is that they have high accuracy by taking into account nonlinear properties of the materials. However, the computational time is important. In this paper, quasi-Newton based algorithm using fmincon Matlab solver and mesh adaptive direct search based algorithm using NOMAD solver are compared by testing several relaxed design problems in order to find an appropriate algorithm for our optimization problem. Finally, we achieve the optimal solution and the shape of the optimal machine is …then validated. Show more

Keywords: Design optimization, NOMAD , fmincon , finite element analysis, wound rotor synchronous machine

DOI: 10.3233/JAE-191108

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. s1-s14, 2019

Authors: Moreno, Sinvaldo R. | Klein, Carlos E. | Mariani, Viviana C. | Coelho, Leandro dos S. | Alotto, Piergiorgio | Torchio, Riccardo | Bauernfeind, Thomas | Baumgartner, Paul

Article Type: Research Article

Abstract: This paper presents the application of the Partial Element Equivalent Circuit (PEEC) approach, which is a full wave electromagnetic modelling technique for conductors embedded in arbitrary dielectrics based on equivalent circuits, to the optimal design of antennas with non-uniform spacing between the array elements. The design optimization problem is solved by means of the new nature-inspired Cheetah metaheuristic. The main aim of this paper is to introduce the Cheetah optimization algorithm to the electromagnetics and antenna community. The results are compared to two well-known optimization algorithms and to show the effectiveness of the proposed algorithm on a realistic benchmark problem.

Keywords: Antenna array, Cheetah optimization algorithm, genetic algorithm, partial element equivalent circuit, particle swarm optimization algorithm

DOI: 10.3233/JAE-191102

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. s1-s10, 2019

Authors: Di Barba, Paolo | Mognaschi, Maria Evelina | Nowak, Tomasz | Blaszczyk, Andreas

Article Type: Research Article

Abstract: A method of free-form optimisation for shaping an electrode surface is proposed in the context of shape design of high voltage devices. The subsequent comparison of various optimisation approaches in dielectric design is developed. In particular, a mesh-based model, driven by free-form optimisation, is presented and compared with a parameter-based model and a NURBS-based model driven by parametric optimisation algorithms. In each model, the electric field analysis is computed by means of the Boundary Element Method. In order to assess the proposed method in a comparative way, the optimal shape design of a L-shaped tunnel electrode and a ring electrode …are considered as the case studies. Show more

Keywords: Free-form optimisation, shape design, dielectrics, boundary element method

DOI: 10.3233/JAE-191109

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. s1-s13, 2019

Authors: Hiruma, Shingo | Igarashi, Hajime

Article Type: Research Article

Abstract: This paper introduces a new method for fast computing of the iron and copper losses in electromagnetic systems. In the method, the finite element equation is reduced to the equivalent Cauer circuit via model order reduction. The nonlinear property due to core saturation is pre-computed and included in the Cauer circuit. While the copper loss is computed as the Jule loss in the circuit, the iron loss is computed in the post process by restoring the field distribution from the solution to the circuit equation with aid of the proper orthogonal decomposition.

Keywords: Cauer circuit, eddy current problems, equivalent circuit, proper orthogonal decomposition

DOI: 10.3233/JAE-191107

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. s1-s8, 2019

Authors: Di Barba, Paolo | Dughiero, Fabrizio | Mognaschi, Maria Evelina | Sieni, Elisabetta

Article Type: Research Article

Abstract: In the paper, a multi-objective optimization of an electrode pair for electrochemotherapy is performed. The aim is to design the electrode pair geometry in order to obtain an effective treatment, which means a homogeneous and suitable electric field distribution. To solve this problem, two recently developed algorithms, M-NSGA and 𝜇-BiMO, are applied.

Keywords: Electric field, electrochemotherapy, finite-element methods, optimal design

DOI: 10.3233/JAE-191114

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. s1-s10, 2019

Authors: Seo, Kyung Sik | Park, Il Han

Article Type: Research Article

Abstract: This paper presents a method for optimizing the shape of the interface between ferromagnetic materials and air in eddy current systems through a continuum sensitivity analysis and level-set method. The continuum sensitivity formula of the eddy current system is obtained as the surface integral form in terms of the velocity field. The shape evolution of the material interface is represented by solving the level-set equation coupled with the common velocity term in the continuum sensitivity formula. The optimization method is validated by shape design examples.

Keywords: Continuum sensitivity analysis, ferromagnetic material, eddy current system, level-set method, shape design

DOI: 10.3233/JAE-191111

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. s1-s8, 2019

Authors: Cirimele, Vincenzo | Dimauro, Luca | Repetto, Maurizio | Bonisoli, Elvio

Article Type: Research Article

Abstract: This paper proposes the study of a magnetic gear by means of multi-objective optimisation. Magnetic gears are structures able to transfer motion between two or more mechanical axles with a given speed ratio. In this aspect they are analogous to a classical mechanical gear but they allow to transfer motion without contact between the moving parts. To replace a standard mechanical gear in an automotive powertrain, the design of a magnetic gear able to transfer the torque needed by the application is required. At the same time, beside the torque, the replacement of the mechanical gear should not alter the …dynamic of the powertrain so that also mechanical parameters, as for instance the moment of inertia, must be considered in the design. To cope with these requirements, a multi-objective optimisation approach is proposed that maximises the transmitted torque per unit mass of the magnetic gear while minimising the moment of inertia of the moving parts. Due to the computational intensive evaluation of the magnetic performance, the optimisation is carried out by a deterministic optimisation algorithm coupled to a weighted sum approach of objectives. Results are discussed and compared with those of a commercial application. Show more

Keywords: Electromechanics, magnetic gears, multi-objective optimization, automotive

DOI: 10.3233/JAE-191103

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. s1-s10, 2019

Authors: Zhang, Lei | Zhuan, Xiangtao

Article Type: Research Article

Abstract: Active electromagnetic isolator systems are used to isolate vibration with variable stiffness and damping, flexible controllability, varied control methods and fast response. In order to achieve better vibration isolation performance, an electromagnetic isolator system is designed with small volume and simple structure and the control block diagram with the nonlinear relationships and PID controller is proposed to simulate and verify in this paper. The structure of the electromagnetic isolator system can not only save space, but also provide the controllable electromagnetic force to counteract external disturbances quickly and actively. For improving the vibration isolation performance of the designed electromagnetic isolator …system, a mathematical model which can accurately reflect the relationship between electromagnetic force and coil current and gap is established using structural information and experimental data. A control block diagram of the electromagnetic vibration isolator system containing nonlinear characteristics with PID controller is then designed. The PID control system shows the good performance of active anti-jamming of the designed isolator system. The experimental result demonstrates that the designed electromagnetic isolator system can effectively isolate vibration, and that the control block diagram with PID controller based on the nonlinear system can effectively describe and control the electromagnetic isolator system. The better vibration isolation performance, such as fast response, less overshoot and so on, can be achieved through deliberately designed controllers. Show more

Keywords: Electromagnetic isolator system, vibration control, PID controller, nonlinear system

DOI: 10.3233/JAE-180112

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-12, 2019

Authors: Bafghi, Mohammad Hossein Barzegari | Vahedi, Abolfazl | Alikhani, Arta Mohammad | Takorabet, Noureddine

Article Type: Research Article

Abstract: Torque transmission along a shaft results in the shaft twisting which is negligible in the conventional motors. However, a long and thin shaft is subject to non-negligible twisting effect. This Phenomenon can affect the electromagnetic performance of the motor. In this article, the shaft twisting effect on the electromagnetic behavior of a flux-switching permanent magnet (FSPM) motor is studied. A model of an FSPM motor is proposed to study the electromagnetic performances of the motor. The electromagnetic torque and twisting rate of each point are calculated along the shaft. Then the model results are compared with finite element analysis results …for a long motor. Show more

Keywords: Shaft twisting, mathematical model, long electric motor, flux switching motor

DOI: 10.3233/JAE-180071

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

Authors: Huang, Songling | Sun, Hongyu | Wang, Shen | Wang, Qing | Zhao, Wei

Article Type: Research Article

Abstract: As the focal position of a line-focusing electromagnetic acoustic transducer (LF-EMAT) affects the intensity of the focal signal, we measure the displacement signal and the selection method of the focal line position is then studied in this work to improve the signal intensity and detection precision for a shear-vertical (SV) wave LF-EMAT. We calculate the magnetostatics field and bulk wave propagation utilizing the finite element method (FEM). We simulate the characteristics of the SV wave, and we find that the radiant distance and propagation direction has a great influence on the amplitude of the displacement of the specimen. The superposition …area of SV waves from different sources possesses better focusing ability, and the triangular area (normalized amplitude of the SV waves lower than 10%) near the surface of a specimen should be avoided to be chosen when designing the meander line coils. As for the line-focusing EMAT described in this manuscript, the selection of focal positions for different thickness specimens or detection depth is completely different. Moreover, we perform an experiment to validate the simulation results and lead to a conclusion that the position of the focal point is required to be appropriately close to the excitation coils to enhance the intensity of the signal, while the best focal position should be calculated. Show more

Keywords: EMAT, line focusing, focal position selection, numerical simulation

DOI: 10.3233/JAE-190021

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

Authors: Guo, Liang | Lu, Wenqi | Cai, Junjun

Article Type: Research Article

Abstract: Double-sided air-cored tubular generators (DSTG) have higher power density than traditional air-cored generators, and are desirable for applications in renewable energy conversion systems. In order to achieve best power quality and maximum efficiency with minimum cost, multi-objective optimization of the DSTG is carried out. Aim to decrease the computational time and guarantee the accuracy of the multi-objective optimization of DSTGs, a new integrated modeling method is proposed and focused in this paper. The new modeling method integrates the analytical models and the machine learning models together. The experimental results prove that the new integrated model can provide higher accurate calculation …results than analytical models and need fewer samples than machine learning models. The optimization time needed by the new model is 5 times shorter than that needed by the FE model. Show more

Keywords: Double-sided tubular generator, machine learning, multi-objective optimization

DOI: 10.3233/JAE-190015

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

Authors: Wang, Siqi | Liu, Yongkai | Li, Decai | Zhang, Zhili

Article Type: Research Article

Abstract: With the emergence of shared bicycles, people travel is more and more convenient. However, the smart bicycle lock with wireless transceiver system must have sufficient electric energy for normal work. In this paper, a ferrofluid-based planar vibration energy harvester is proposed to convert low-frequency vibration energy into electrical energy. The electromagnetic generator is designed and studied experimentally. The energy harvesting system is installed in the backseat and the front basket turning with the front fork, respectively. Experimental results indicate the collected energy is 0.010 J in the backseat and 0.020 J in the front basket for the maximal experiment distance of 1.16 km, …respectively, which can meet the demand of the smart bicycle lock. Show more

Keywords: Ferrofluid, energy harvester, shared bicycle, vibration

DOI: 10.3233/JAE-180123

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

Authors: Klach, Moufida | Aloui, Helmi | Neji, Rafik

Article Type: Research Article

Abstract: This paper presents the modeling by Magnetic Equivalent Circuit model (MEC) of a Simple Excited Automotive Alternator (SE2A) where DC-excitation winding is transferred from rotor side to stator one rather than in conventional automotive claw pole alternators, to overcome the disadvantages of the ring-brush system. Following the resolution of the MEC using Newthon-Raphson numerical method, the alternator performances at both no-load and under resistive load regimes are achieved considering the saturation effect. It has been found that alternator’s performances carried out using the proposed MEC are with closed proximity to experimental records on a built prototype of the considered alternator. …Then, a modified SE2A is proposed by the integrating Barium ferrites permanent magnets between adjacent rotor claws in order to combine the high-energy density of permanent magnets with the commonly controllability. This configuration is named the Hybrid Excited Automotive Alternator (HE2A). The improvement of its topology performance is provided through the optimization of the device topology based on a Sequential Quadratic Programming (SQP) coupled to a magnetic equivalent circuit considering iron losses minimization case. It has been found that the efficiency of the alternator could be improved especially at high speed rate. Show more

Keywords: Claw pole alternator, simple excitation, experimental tests, hybridization, optimization, iron losses

DOI: 10.3233/JAE-170021

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

Authors: Xu, Yongming | Ai, Mengmeng | Wang, Wenyi | Wang, Yaodong

Article Type: Research Article

Abstract: Due to the high rotational speed, the permanent magnet of surface-mounted high-speed permanent magnet generator is easily damaged by the centrifugal force. So a high strength alloy sheath is installed to protect the permanent magnet. The material, thickness and eddy current loss of the composite sheath of the high-speed permanent magnet generator with rotor strength constraint is studied thoroughly in this paper. Generator rotor strength under different limit conditions is calculated by numerical analysis method based on the thick-cylinder theory of elastic mechanics. Various methods have been used to reduce the eddy current. The composite sheath of high-speed permanent magnet …generator on the basis of rotor strength constraint is presented. Change of the material, thickness of each layer of the sheath is determined by calculation of stress and eddy current loss and optimized design of composite sheath with reasonable stress distribution and lower eddy current loss. Strength test of prototype rotor is carried out. Show more

Keywords: Electromagnetic high-speed permanent magnet generator, strength constraint, composite sheath, eddy current loss

DOI: 10.3233/JAE-180117

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

Authors: He, Yichao | Liang, Guanqun | Xue, Bing | Peng, Zhizhao | Wei, Yintao

Article Type: Research Article

Abstract: Magnetorheological (MR) damper is one of the key technologies in the field of semi-active suspensions. However, the dynamic model and control strategy are not yet well established. A unified MR damper model and its inverse characterization are proposed to investigate MR damper dynamics. First, a novel unified model is proposed to describe the shear term of the MR damper force. This forward unified MR damper model uses one set of parameters to describe all MR force behavior under all currents and velocities, which agrees well with experimental data. Then, an inverse MR model based on the adaptive neuro-fuzzy inference system …(ANFIS) technique has been established, where the precise training data are obtained from the proposed unified hysteretic model. A clear step-wise modeling process is proposed to decrease coupling degree of system which can be beneficial to improve inverse modeling efficiency. The inverse MR model is used for a semi-active suspension control, which can obtain the excitation current, exactly tracking the desired damping force computed by suspension control algorithm. Finally, validation of the proposed ANFIS inverse model has been conducted by comparison with three traditional empirical inverse approaches. The results reveal that the ANFIS inverse model could achieve much more tracking capability for the desired damping force and thus contributes to the development of semi-active suspension controllers. Show more

Keywords: Magnetorheological damper, unified model, inverse characteristics, adaptive neuro-fuzzy inference system, suspension controller

DOI: 10.3233/JAE-180114

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-21, 2019

Authors: Zhang, Xiao | Li, Changxing | Wang, Xiaoguang | Zhao, Yun | Li, Liang

Article Type: Research Article

Abstract: The controllability of the distribution of Lorentz force on tube is poor in electromagnetic forming when using a conventional single coil forming system. To solve this issue, a triple-coil forming system was developed in this work, which includes three coils and two independent power supplies. To validate the effectiveness of the system, experimental studies for the forming of aluminium tube AL6061 under different conditions were carried out. Results showed that when using this novel forming system, the deformation behavior of tube can be obviously improved, including larger deformation depth, better performance of sizing, and lower occurrence of cracking.

Keywords: Electromagnetic forming, lorentz force distribution, deformation depth, sizing, cracking

DOI: 10.3233/JAE-180122

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

Authors: Yao, Xing-Yan | Pecht, Michael

Article Type: Research Article

Abstract: Magnetorheological (MR) dampers are important devices for reducing and controlling vibration. Dynamic response time is one of the key factors that determines the control ability and application of the MR damper. Metal foam MR dampers are potentially superior to conventional dampers due to their low cost and fast response. The dynamic response time of metal foam MR dampers is distinct from conventional dampers. In this paper, the effects of different metal foam materials on the dynamic response time of metal foam dampers are studied. Three response time parameters were defined, and an experimental system including a DC motor, force sensor, …damper, and time relay was designed to collect dynamic response time parameter values using metal foam Cu and Ni, respectively. The experimental results show that the response time of MR dampers is faster using Ni rather than Cu metal foam due to the different permeability of the materials. The magnetic resistance model and Ansys simulation further prove that magnetic flux density is the main contributor to the differences in response time. Show more

Keywords: Magnetorheological (MR) fluid, MR damper, metal foam, dynamic response time

DOI: 10.3233/JAE-190022

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

Authors: Coufal, Oldřich | Bátora, Branislav | Radil, Lukáš | Toman, Petr

Article Type: Research Article

Abstract: A method is proposed for the calculation of current density in a long solid metallic conductor placed in an external variable magnetic field. The external magnetic field is perpendicular to the conductor and constant on straight lines parallel to the conductor. The conductor is passive, connected to neither a voltage source nor a current source. It is assumed that the external magnetic field is quasi-stationary and is not affected by the magnetic field of the currents induced in the conductor under examination. The frequency of external field does not exceed 1 MHz and the displacement current is neglected. The proposed method …enables the calculation of current density not only in the steady state but also in the case that the external field has an arbitrary time-dependent course. Results are given of the calculation of current density in conductors with symmetrical and unsymmetrical cross section, with constant and non-constant resistivity in the conductor cross section, for both homogeneous and non-homogeneous external steady-state sinusoidal field, and for switching the external sinusoidal field on and off. Show more

Keywords: Applied classical electromagnetism, magnetic induction, eddy currents, numerical simulation

DOI: 10.3233/JAE-180118

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-24, 2019

Authors: Ye, Lezhi | Liu, Yupeng | Li, Desheng

Article Type: Research Article

Abstract: We propose a novel dual air-gaps and liquid-cooled eddy current retarder (ECR) based upon observing the (1) heat fade of the continuous braking and (2) large rotor weight of the traditional ECR for heavy vehicles. The new ECR maintains a low working temperature because of the liquid cooling stator structure. The eddy current distribution and braking torque characteristic curves are obtained by finite element method (FEM). Combining with 3-D FEM, Kriging approximation model is employed to optimize the structural parameters of rotor tooth. Based on the optimization method, the number of rotor teeth is determined to be 12. The braking …torque increases by 14.8% after optimization and the rotor tooth weight decreases by 9.5%, which reduces the adverse influence on the vehicle transmission system. The bench test was carried out to verify the optimized calculation results and the braking torque can be stepless controlled by adjusting the excitation current. Compared with traditional ECR, the dual air-gaps and liquid-cooled ECR has better continuous braking performance and is more suitable for heavy vehicle auxiliary braking. Show more

Keywords: Dual air-gaps, eddy current retarder, liquid cooling, Kriging model, structural optimization

DOI: 10.3233/JAE-180109

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

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

Article Type: Research Article

Abstract: Based on the invalidation and damage of the field effect transistors under lightning radiation, we establish the breakdown experiment with open-circuit voltage wave and the protection experiment with TVS as the protection device. The junction field effect transistor and the metal oxide semiconductor field effect transistor are used as material. We draw some conclusions. In the breakdown experiment, the breakdown voltage of the MOSFETs is higher than that of the JFETs as a whole. The MOSFET can be adopted in the amplifier circuit which is expected to get higher input resistance and breakdown voltage. The drain-source resistance can recover to …the original resistance value after being placed a period of time, but the gate-source resistance is irreversible. The invalidation of the device under test is due to the breakdown of gate-source. The TVS can protect the FTEs well. The change of pin resistance of the MOSFET is inconspicuous. MOSFETs are more stable for debugging and development of the amplifier circuit. The results provide some significance for the development and improvement of the lightning electric fields change measuring instruments in the future. Show more

Keywords: Field effect transistor, JFET, MOSFET, invalidation

DOI: 10.3233/JAE-180100

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

Authors: Ouili, M. | Mehasni, R. | Feliachi, M. | Belounis, A. | Latreche, M.E.H.

Article Type: Research Article

Abstract: The aim of this work is the investigation of the simultaneous separation of magnetic (𝜇r > 80) and conductive (𝜎 ≈ 6 ×107  S/m) particles in a designed magnetic separator. Such a separator consists mainly of a drum on which permanent magnets are arranged and a conveyor belt carrying the material to be purified. The separately driving of the drum and the conveyor belt allows the independent control of the frequency of the generated magnetic field and the displacement speed of the material to be treated. To generate high magnetic field, identical NdFeB permanent magnet bars with residual magnetic flux …density B r = 1.2 T are used. To compute the particles trajectories, the magnetic field and the particle dynamic governing equations have been solved using the numerical finite element (FEM) and Runge Kutta (RK4) methods. The computing results have shown that the proposed separator permits the simultaneous separation of magnetic and conductive particles. To check the validity of the numerical results, experiments have been carried out on ferromagnetic powder and conductive particles of different sizes. Show more

Keywords: Magnetic separation, drum, particle trajectories, finite element, permanent magnets

DOI: 10.3233/JAE-180101

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

Authors: Zhang, Pengfei | Wang, Zhiheng | Xi, Guang

Article Type: Research Article

Abstract: This paper proposes a general multi-objective optimal design methodology for a new type of no-thrust-disk/thrust hybrid magnetic bearing that has been designed to reduce wind loss in centrifugal compressors. The approach dispenses with initial design results and has adjustable design objectives. To establish the proposed method we begin with its conceptual design, then look at how a parametric geometric model can facilitate manufacture, installation and cooling, before presenting a magnetic circuit model that can take into account eddy-current effects and significant magnetic leakage. The key optimization objectives selected include bearing capacity, mass, axial length, copper loss, iron loss, wind loss, …and outer diameter. The approach also takes into account the performance deterioration of permanent magnets at high temperatures. By using an optimization method that combines penalty factor and selection factor, we have been able to incorporate a function for adjusting and re-adjusting the optimization goals. To verify the validity of the approach we present a concrete design case. Out of four possible schemes, a scheme based on minimum mass and axial length proves to be the best solution in this example (assuming sufficient cooling capacity). Show more

Keywords: Thrust hybrid magnetic bearings (THMB), equivalent magnetic analysis, multi-objective optimization (MOO), eddy-current effect, wind loss

DOI: 10.3233/JAE-180062

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-30, 2019

Authors: Tang, Mingdong | Gu, Youlin | Wang, Shigang | Liang, Qinghua | Wang, Xiaoxi

Article Type: Research Article

Abstract: With the popularization of intelligent substations, hot-line working robots that can replace the manual operation without shutting down the power of the corresponding equipments are increasingly widely applied in the maintenance and monitoring of substations. Robotic operation can ensure the safety of the operators and reliability of operation while improving the economic benefits of substation. However, because of the compact structure of the intelligent substations, the operating space is small. Further, as the main material of hot-line working robots is metal, which greatly changes the strength and distribution of the electric field around its working position when entering the working …position and in the process of operation. In serious cases, interphases or phase to ground air breakdown occurs. Hence the working space of hot-line working robots is limited not only by the narrow space between devices in the substation but also by the electrical safety clearance of phase to phase and phase to ground. Therefore, it is necessary to find a safe working space (“SWS”) for the robot which should not be too small for the robot to accomplish the task effectively. The purpose of this paper is to provide: (i) a design reference for hot-line working robots which can not only guarantee the electrical safety distance but also minimize the effect to the electric field and (ii) a method to find the SWS of the robot in which the robot can accomplish the task effectively with the example of the hot-line working robot for isolated circuit breaker (“ICBot”). We analyze the influence of different installation positions and postures of the manipulators on the electric field in this paper and present a calculation method of the SWS of the manipulator in a very non-uniform electric field caused by the intervention of manipulators, which is significant to the research on hot-line working robots. The SWS has been tested in simulated and energized experimental system, and the experiment results show that the robot can work safely and efficiently. Show more

Keywords: Hot-line robot, electric field distortion, air breakdown, substation insulation

DOI: 10.3233/JAE-180057

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

Authors: Aguib, Salah | Nedjar, Ali | Zerrouni, Nassim | Djedid, Toufik | Tourab, Mohamed | Guedifa, Réda

Article Type: Research Article

Abstract: This paper is devoted to an experimental and theoretical study of the magneto-mechanical behavior of an elastomer loaded with 25% of ferromagnetic particles of micrometric size; elaborated under the action of a magnetic field. The characterization of the rheological properties and the interaction between the micron size ferromagnetic particles as a function of the intensity of the magnetic field are studied. The results obtained clearly show a high energy dissipation properties of the composite, accentuated by its modified structure from the interaction forces between the particles that are aligned, which gives adjustable viscoelastic structures properties, depending on the volume fraction …of particles and the magnetic field intensity. Show more

Keywords: Magneto-mechanical behavior, micrometric particles, rheological properties, magnetic force, elastomer

DOI: 10.3233/JAE-180108

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

Authors: Shi, Minxia | Zhang, Xuanrui | Qiu, Aici | Li, Junhao

Article Type: Research Article

Abstract: As the core material of electrical equipment, electrical steel sheet is often under rotational magnetization and DC-biased magnetization simultaneously. The rotating magnetic flux density, rotating magnetic field strength and total iron loss density under various DC-biased magnetizing condition are measured and analyzed in this paper to investigate the effects of DC magnetizing angle and amplitude on rotating magnetic properties. An improved model considering saturation and hysteresis is established for describing the rotating magnetic properties of electrical steel sheet under DC-biased field based on experimental results. It can be concluded that offset and distortion of the rotating magnetic parameters loci occur …with the increase of DC-biased magnetization. When the electrical steel sheet is magnetized to deep saturation, the total loss density decreases due to the diminishment of magnetic domain walls. The impact of DC-biased excitation on rotating properties is most obvious in hard magnetization direction. Show more

Keywords: Electrical steel sheet, DC-biased magnetization, rotating magnetic properties, iron loss density

DOI: 10.3233/JAE-180125

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

Authors: Wu, Jian | Sun, Jikang | Zhang, Tao | Sun, Hongbing | Ji, Sai | Sun, Yajie

Article Type: Research Article

Abstract: At present, the sampling rate in a wireless sensor network is generally low, which does not meet the requirements for high-speed sensor signal acquisition and detection. To address the shortcomings of wireless sensor networks in terms of the design methods and effects assessment, a high-speed wireless sensor network node was designed based on structural health monitoring. Based on the general framework of a wireless sensor node, combined with the requirement of active health monitoring, a test of screws loosening in a reinforced aluminum plate were conducted. The theory of compressed sensing was used to test the effects of compressed sampling …for the high-speed acquisition nodes. The results demonstrated that high-speed wireless sensor nodes could complete active excitation, sampling, and processing of the response signal for the application of active structure monitoring with integrated software and hardware and that the system could distinguish the looseness of the screws in the aviation specimens accurately. The nodes also met the requirements of small size, low cost, and low power consumption. The results of the experiment verified that the hardware and software modules for the high-speed wireless sensor nodes functioned and monitored the structural damage effectively. The system solves many key problems of node design in wireless sensor networks in the industrial field. Show more

Keywords: Wireless sensor network (WSN), structural health monitoring (SHM), high-speed sampling

DOI: 10.3233/JAE-170051

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-24, 2019

Authors: Wajnert, Dawid

Article Type: Research Article

Abstract: A hybrid magnetic bearing (HMB) with six poles is an effective construction of the magnetic bearing. It is energy efficient due to the presence of permanent magnets and it can be supplied from a three phase inverter. Unfortunately, the cross-coupling effect and nonlinearity of magnetic force occur in the 6-pole construction of the HMB. The purpose of this paper is to investigate the cross-coupling effect and nonlinearity of magnetic force as well as to propose two methods of reducing them. The proposed methods include division of the stator joke into three parts and exciting an additional current in one winding. …Presented HMB was analysed with the 3D finite element method. The numerical model was verified by measurement. Show more

Keywords: Hybrid magnetic bearing, electromagnetic calculations, cross-coupling effect, magnetic nonlinearity

DOI: 10.3233/JAE-180088

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

Authors: Martinez-Muñoz, Miriam | Diez-Jimenez, Efren | Sanchez-Montero, Rocio | Lopez-Espi, Pablo Luis | Martinez-Rojas, Juan Antonio

Article Type: Research Article

Abstract: Magnetic actuators, magnetic gears, vibrational energy harvesters and other micro-electromagnetic devices requires micro-magnetic rotors with alternant magnetizations to optimize their performance. Different approaches have been used for multipole magnetization of micro-magnets like fixed micro-fixtures, thermomagnetic patterning or laser machining. The main limitation of previous techniques is that the inversion of the magnetic polarizations is done only partially. In this work, a concept based on 2D multipole magnetization printing of micro-magnets is proposed and analyzed to overcome current limitations. The fixtures are designed to be printed on a standard 35 μm PCB. The dependence of the magnetizing field with respect to the …geometrical parameter of the fixture is analyzed. Maps of the required current for the magnetizing fields are also given. Some design recommendations to optimize the magnetizing field and to minimize current, thus the heat, are given. Show more

Keywords: Magnetizing fixtures, magnetic polarization patterning, micro-magnets

DOI: 10.3233/JAE-180121

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

Authors: Cheng, Yuhua | Qian, Gaorong | Chen, Guoxiong | Sun, Haoran | Wang, Gaofeng

Article Type: Research Article

Abstract: L-type impedance matching circuits (IMCs) can maximize the power transfer efficiency (PTE) by converting the load to the optimum one in the wireless power transfer system. However, their effectiveness is inadequately studied. In this work, the applicability of the L-type IMCs is carefully examined under the restriction of capacitance realization. The sensitivities with respect to the deviation of the capacitance in mass production as well as the variations of the load and the mutual inductance are analyzed in detail and validated by experiments. By comparison with the basic-type IMCs, the L-type IMCs have higher, nearly equal and lower sensitivities with …respect to the deviation of the capacitance, the variation of the load, and the variation of the mutual inductance, respectively. Show more

Keywords: L-type impedance matching circuit, sensitivity, power transfer efficiency

DOI: 10.3233/JAE-180089

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