International Journal of Applied Electromagnetics and Mechanics - Volume 65, issue 4

Authors: Li, Jianqi | Zhou, Yu | Li, Jianying

Article Type: Research Article

Abstract: This paper presented a novel analytical method for calculating magnetic field in the slotted air gap of spoke-type permanent-magnet machines using conformal mapping. Firstly, flux density without slots and complex relative air-gap permeance of slotted air gap are derived from conformal transformation separately. Secondly, they are combined in order to obtain normalized flux density taking account into the slots effect. The finite element (FE) results confirmed the validity of the analytical method for predicting magnetic field and back electromotive force (BEMF) in the slotted air gap of spoke-type permanent-magnet machines. In comparison with FE result, the analytical solution yields higher …peak value of cogging torque. Show more

Keywords: Magnetic field, permanent-magnet machines, conformal transformation, spoke-type, slots

DOI: 10.3233/JAE-201505

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 65, no. 4, pp. 609-622, 2021

Authors: Zhang, Yunpeng | Wang, Houfu | Gao, Shuning | Liu, Shuqin

Article Type: Research Article

Abstract: The axial and radial load capacity of axial hybrid magnetic bearing (HMB) is critical for the magnetic levitation system. In this paper, the effect of permanent magnet (PM) position on axial and radial magnetic force and stiffness in axial HMB is investigated. Six different configurations are considered and the equivalent magnetic circuits of HMBs for each configuration is built and studied based on the distribution of magnetic field and magnetic leakage. The dependence of axial and radial magnetic force and stiffness on the axial displacement, radial displacement and control current is calculated and investigated for different configurations. To validate the …calculated results, the axial and radial magnetic forces for each configuration are simulated by finite element method. A good agreement between the calculated and simulated results validated the proposed magnetic circuit models. Show more

Keywords: Hybrid magnetic bearing, permanent magnet position, load capability, equivalent magnetic circuit, finite element method

DOI: 10.3233/JAE-190149

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 65, no. 4, pp. 623-641, 2021

Authors: Song, Shouxu | Hu, Mengcheng | Xia, Yan

Article Type: Research Article

Abstract: In order to optimize and analyze the cogging torque of hybrid stator motor, a hybrid stator motor is taken as the research project. The axial distribution of air gap magnetic flux density was analyzed, and the analytical formula of the cogging torque of the hybrid stator motor was derived. Combined with the cogging torque analytical formula, the superposition calculation method of cogging torque of hybrid stator motor was proposed, and the correctness of the superposition calculation method was verified by simulation analysis. The silicon steel segment and the amorphous alloy segment of hybrid stator core were optimized by using the …uneven air gap structure, and the optimized results of the silicon steel segment and the amorphous alloy segment were obtained by two-dimensional simulation. Based on the results of two-dimensional simulation analysis, a three-dimensional model was built for simulation analysis. After optimization, the cogging torque of the motor was weakened by 48.1% and the torque ripple was reduced by 1.32%, while the loss and output torque remained basically unchanged. Show more

Keywords: Hybrid stator, cogging torque, superposition calculation method, uneven air gap

DOI: 10.3233/JAE-190159

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 65, no. 4, pp. 643-659, 2021

Authors: Bu, Wenshao | Zhang, Fei | Chen, Youpeng | Zhang, Xiaofeng

Article Type: Research Article

Abstract: As for the inverse decoupling control system of a bearingless induction motor (BL-IM), in order to eliminate the influence of rotor resistance variation on its control performance, on the basis of the reactive power calculation of torque system, a novel fuzzy model reference adaptive (MRAS) identification method of rotor resistance is proposed. The reference model and adjustable model of instantaneous reactive power are derived in detail. In order to improve the identification performance of rotor resistance, a fuzzy PI adaptive law based on popov super stability theory is constructed. On this basis, a rotor resistance identifier is constructed, and it …is used to on-line correct the rotor resistance parameter in the inverse system mathematical model of a BL-IM system. Based on the inverse decoupling control system of a BL-IM, the simulation experimental analysis and verification are carried out. The simulation experimental results have shown that when the proposed identification method of rotor resistance is used, not only the identification- and tracking-speed of rotor resistance can be effectively improved, but also the identification accuracy of rotor resistance can be improved; as for the BL-IM system, after the rotor resistance parameter is on-line corrected, not only the inverse dynamic decoupling control performance can be effectively improved, but also the robustness of BL-IM system to the variation of rotor resistance parameters can be improved. Show more

Keywords: Bearingless induction motor, instantaneous reactive power, MRAS rotor resistance identification, fuzzy PI adaptive law, inverse system decoupling control

DOI: 10.3233/JAE-200018

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 65, no. 4, pp. 661-680, 2021

Authors: Zhao, Qiang | Zhu, Baoquan | Pei, Yulong | Wang, Na

Article Type: Research Article

Abstract: This paper investigates how to control suspension system and steering system to cooperatively ensure their performance. A model predictive controller is designed for their integrated model, which includes three parts: predictive model, rolling optimization and online correction. Repeated online optimization is based on actual output feedback information, real-time consideration of the impact of uncertainties, and timely correction. The simulation results show that the integrated model predictive control effect of steering system and suspension system is better than those of non-integrated passive control and integrated optimal control. The ride comfort, handling stability and driving safety of the vehicle are all improved …with the integrated model predictive control. Show more

Keywords: Integrated control, model predictive algorithm, electric power steering, active suspension

DOI: 10.3233/JAE-201519

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 65, no. 4, pp. 681-701, 2021

Authors: Aditya, Kuragayala | Bobba, Phaneendra Babu | Satyavani, Yadlapalli

Article Type: Research Article

Abstract: Wireless power transfer system is playing an important role in biomedical applications by transferring power wirelessly to the implants present in the body. In this paper, magnetic coupling resonance wireless power transfer system is used to recharge battery of implantable cardioverter defibrillator. The proposed system operates at 300 KHz frequency. The LCC-C compensation topology is used to tune the coils for operating the system at stable resonant frequency and to obtain higher efficiency. In this paper, we have investigated the performance of different coil structures in multiple layer configurations and we offer recommendations on the best suitable configuration for effective transfer …of power. Show more

Keywords: Implantable cardioverter defibrillator (ICD), LCC-C compensation, magnetic coupling resonance (MCR), wireless power transfer (WPT)

DOI: 10.3233/JAE-201524

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 65, no. 4, pp. 703-714, 2021

Authors: Li, Ke | Ling, Feng | Sun, Xiaodong | Yang, Zebin

Article Type: Research Article

Abstract: In this paper, a novel decoupling control scheme combining least squares support vector machines (LSSVM) inverse models and 2-degree-of-freedom (DOF) internal model controllers (IMC) is employed in the decoupling control system of the bearingless permanent magnet synchronous motor (BPMSM). This scheme can be used to enhance the control properties of high-precision, fast-response, and strong-robustness for the BPMSM system, and effectively eliminate the nonlinear and coupling influence. It introduces LSSVM inverse models into the original BPMSM system to constitute a decoupled pseudo-linear system. In addition, the particle swarm optimization algorithm (PSO) is used to optimize parameters of the LSSVM, which improves …its fitting ability and prediction accuracy. What is more, the internal model control scheme is used to design additional closed-loop controllers, thereby improving the robustness of the entire control system. Therefore, this scheme successfully combines the advantages of the LSSVM inverse models and the internal model controller. It can enhance the stability and the static as well as dynamic properties of the whole BPMSM system while independently adjusting the tracking and interference rejection performances. The effectiveness of the proposed scheme has been verified by simulation results at various operations. Show more

Keywords: Bearingless permanent magnet synchronous motor (BPMSM), invert decoupling control, internal model controllers, least squares support vector machines (LSSVM)

DOI: 10.3233/JAE-201529

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 65, no. 4, pp. 715-734, 2021

Authors: Wang, Tingting | Zheng, Changbao | Zhou, Rui | Wang, Qunjing | Ju, Lufeng | He, Jingxiong

Article Type: Research Article

Abstract: The magnetic field and torque of permanent-magnetic spherical motor (PMSpM) are difficult to analyze due to the complicated structure, and therefore are often analyzed by the finite-element method (FEM) or Lorentz force method, with large amount of calculation and time consumption. This paper first establishes a three-dimensional (3-D) magnetic field analytical model of a spherical motor with permanent magnets (PMs) by the equivalent surface current method. Secondly, through the Lorentz force spatial integration of energized stator coil, a torque analytical model is established. Thirdly, in order to avoid repeated integration operation, a torque interpolation model based on torque Map is …established. Both magnetic field and torque analytical models are verified by comparing with FEM and the experiment respectively. It is shown that the method proposed not only ensures the modeling accuracy but also significantly speeds up the analysis. Show more

Keywords: Permanent-magnet spherical motor (PMSpM), Lorentz force method, Torque modeling, Interpolation calculation

DOI: 10.3233/JAE-201538

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 65, no. 4, pp. 735-752, 2021

Authors: Mingliang, Zheng

Article Type: Research Article

Abstract: The spin Hall effect of electromagnetic wave has important application prospects in the fields of Optical-electromechanical conversion, condensed matter and high energy physics. Based on the Euler–Lagrange equations of electromagnetic field by four-dimensional covariation, a deflection model of electromagnetic wave reflecting and refracting on interface of media is established in this paper. By using Lie group analysis method, the allowable infinitesimal symmetries, conserved quantities of partial differential equations and motion equation of energy center are derived. More importantly, their detailed analytical expressions and properties are given. The content of this paper can reveal the mechanism and influencing factors for transverse …shift of the electromagnetic wave energy center, and provide a powerful theoretical basis for the numerical simulation of nonlinear photoelectric wave equation and spin regulation. Show more

Keywords: Electromagnetic wave, Lie symmetries, conserved quantities, transverse shift

DOI: 10.3233/JAE-201543

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 65, no. 4, pp. 753-761, 2021

Authors: Xu, Hao | Chen, Long | Sun, Xiaodong

Article Type: Research Article

Abstract: Permanent magnet synchronous hub motors (PMSHMs) have been gradually introduced into the applications of electric vehicles. In order to output more torque, many researchers turned their research direction to six-phase motors. Because it is composed of two sets of three-phase windings, there will be interference between the windings, affecting the performance of the motor. In order to improve the steady and dynamic-state performance of permanent magnet six phase synchronous motor, a predictive torque control method based on multi vector model is proposed in this paper. Finally, experimental results show the effectiveness of this method.

Keywords: Auxiliary voltage vectors (AVVs), model predictive torque control (MPTC), permanent magnet synchronous hub motors (PHSHM)

DOI: 10.3233/JAE-201550

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 65, no. 4, pp. 763-779, 2021

Authors: Meng, Kai | Gu, Yong | Ma, Jianhui | Liu, Xidong | Geng, Xiangqian | Liu, Yuxi | Liu, Xuhe | Zhang, Haoming | Shao, Fengxiang

Article Type: Research Article

Abstract: In this study, a novel negative stiffness spring is developed. The developed spring possesses the characteristics of the controllable stiffness and can be employed in vibration isolation system with a low resonance frequency. The controllable electromagnetic negative stiffness spring (CENSS) is obtained by the coaxial permanent magnets (PMs) and the circular current-carrying coils. The stiffness control is accomplished by changing the current in the coils. Furthermore, the mathematical model of CENSS is established, based on the filament method. According to the model, the relationship between the exciting current and the axial stiffness is obtained. Moreover, the influence of the structural …parameters of CENSS on the magnetic force and the stiffness is analyzed. The results demonstrate that the thickness of PMs and the coils have the ability to adjust the range of the negative stiffness. Finally, performance experimental study of CENSS in the stiffness domain is carried out under different exciting currents and thicknesses. The experimental results have shown a good agreement with the model. It demonstrates that the performance of negative stiffness in CENSS can be controlled efficiently by the exciting current and optimized by the thickness. Show more

Keywords: Magnetic stiffness, electromagnetic springs, negative stiffness, vibration isolation

DOI: 10.3233/JAE-201561

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 65, no. 4, pp. 781-802, 2021

Authors: Liu, Chuan | Chen, Renwen | Zhang, Yuxiang | Wang, Liping | Qin, Jinchang

Article Type: Research Article

Abstract: Converting persistent and renewable wave energy into electricity has been studied in recent years. This research develops a novel fully floating three-body direct-drive wave energy converter (DD-WEC) prepared for the research of the multi-body DD-WEC. Its prototype consists of three floating bodies, but both three bodies act as buoys to extract the wave energy, not just a body. And the relative motion of the buoys induces the voltage in Halbach array permanent magnet linear generators coils. Its feasibility is investigated theoretically by analyzing the dynamics of motion of the floating buoys. As a result, parametric design of the WEC is …achieved. The load performance of the DD-WEC is investigated by using the Simulink, and it can be found that the relative displacements between buoys are different. Then, the electromagnetic power of the proposed WEC is much higher compared to a two-body DD-WEC by using numerical simulation Finally, the DD-WEC prototype is manufactured and tested in the wave tank. The results show that the WEC can produce the most electricity for the case with the wave period of 1.6 s, and the maximum voltage reaches 14.2 V, which is consistent with the simulation results. The results show that the proposed DD-WEC is well suited for wave energy conversion. Show more

Keywords: Three-body, direct-drive wave energy converter, Halbach permanent magnet linear generator, electromagnetic power

DOI: 10.3233/JAE-201566

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 65, no. 4, pp. 803-818, 2021