International Journal of Applied Electromagnetics and Mechanics - Volume 66, issue 3

Authors: Li, Ming | An, Yuejun | Zhang, Zhiheng | Deng, Wenyu | Wang, Guangyu | Qi, Lijun | Kong, Xiangling | Bi, Delong | Shi, Yong | Zhu, Sheng

Article Type: Research Article

Abstract: Canned induction motors fed by inverters are widely used in pharmaceutical, chemical, and nuclear fields. It is necessary to analyse the effect of time harmonic injected by the inverter on the performance of the canned induction motor. However, the existing researches are to consider the inverter and the motor separately, without analyzing the reverse effect of the induction motor as a nonlinear active load on the time harmonics of the inverter. Therefore, this paper establishes a field-circuit coupling analysis model of the canned induction motor considering the influence of load, and studies the effect of time harmonic current under different …load conditions on the electromagnetic field, eddy current loss, and temperature field of the canned induction motor. The paper first uses the analysis method to determine the relationship between the time harmonic voltage of the inverter and the time harmonic current of the motor. Then, the electromagnetic field distribution, eddy current loss, and temperature field distribution of the canned induction motor under different load conditions are calculated. Besides, the laws of time harmonic current on the electromagnetic field, can loss and motor temperature distribution are found. These research results can not only provide a meaningful reference for analysis of the canned induction motor but also provide methods for design optimization and multi-physical field modeling analysis of the canned induction motor. Show more

Keywords: Canned induction motor, time harmonic, can eddy current loss, field-circuit coupling analysis, temperature field

DOI: 10.3233/JAE-201552

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 66, no. 3, pp. 369-385, 2021

Authors: Jia, Chen | Xu, Liang | Ji, Jinghua | Zhao, Wenxiang

Article Type: Research Article

Abstract: By incorporating the merits of partitioned stator and flux modulation techniques, the partitioned stator flux modulation motors featuring high torque, have attracted much attention. This paper investigates four partitioned stator flux modulation motors with different types of PM arrays, including surface-mounted type, consequent-pole type, Halbach-array type, and half-Halbach type. The influences of key parameters on the average electromagnetic torque is conducted and compared. Then, based on the optimal designs, four motors are compared in terms of magnetic field distribution, back-electromotive force, torque characteristics, loss and overload ability. The result reveals that the half-Halbach motor is capable of utilizing more PM …to improve electromagnetic torque. Also, the consequent-pole motor achieves the highest torque per PM usage. In addition, performance comparison under the same PM usage is carried out. The result shows that the half-Halbach motor not only exhibits the highest average torque but also achieves the highest PM utilization. Last, the prototype of half-Halbach motor is built for experimental verification. Show more

Keywords: Partitioned stator, permanent magnet motor, Halbach array, flux-modulation

DOI: 10.3233/JAE-201563

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 66, no. 3, pp. 387-405, 2021

Authors: Gong, Yongxing | Xu, Fengqiu | Xu, Xianze | Zhang, Kaiyang

Article Type: Research Article

Abstract: Precision machining fields require the worktable to have a large-scale multi-degree-of-freedom motion capability. In order to provide a more accurate magnetic model for the control strategy decoupling process and the size parameter optimization design process of the maglev rotary table. This paper proposes a new magnetic modeling method based on the Two-Dimensional Harmonic method. Different from the existing harmonic method, this method simultaneously considers the tangential and radial magnetic field changes of circumferential magnetic array. And it eliminates the edge effect of the magnetic flux density distribution in the radial aperiodic direction. The magnetic force and torque are solved by …the Lorenz integral formula and the Gaussian quadrature method. In order to verify the accuracy of the TDH method, the boundary element software RadiaTM is used for simulation, and a prototype is made for measurement. The experimental results shown that this method reduced the maximum error of the radial edge magnetic field from 104.19% to 3.29%. And it improved the calculation accuracy of magnetic force and torque by 60.74% and 84.39% respectively. This method does not rely on special example, and is beneficial to cross-platform applications. It is more suitable for realizing the magnetic modeling of the maglev rotary table with both rotational motion and large-stroke translational motion. Show more

Keywords: Circumferential magnetic array (CMA), edge effect, maglev rotary table, two-dimensional harmonic (TDH) method, magnetic modeling method

DOI: 10.3233/JAE-201567

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 66, no. 3, pp. 407-424, 2021

Authors: Halim, Mohd Firdaus Mohd Ab | Sulaiman, Erwan | Othman, Raja Nor Firdaus K. Raja

Article Type: Research Article

Abstract: The inclusion of high energy density permanent magnet (PM) in MG contributes to the high eddy current loss in magnetic gear and reduces its efficiency. There was limited research done that focused on gear efficiency behavior over a broader range of speed and in different gear ratios. In this paper, the function of gear efficiency concerning gear ratio and rotational speed is proposed. Torque and eddy current loss data were obtained through transient magnetic analysis using finite element software at several rotational ranges and gear ratios. The analytical approach through mathematical substitution was discussed to confirm the finding in the …simulation. The result showed that the gear efficiency decreases as the speed increases. Nonetheless, the gear efficiency revealed improvement in efficiency as the gear ratio increases. Finally, gear efficiency behavior was modeled using the curve fitting method. Subsequently, based on the correlation study, an equation was proposed, yielding a 1% error compared to the new simulated data. With this proposed method and equation, the analysis and estimation of gear efficiency behavior over wider speed and gear ratios are simplified, thus reducing the need to perform simulation over different speeds and gear ratios. Show more

Keywords: Magnetic gear, machine design, gear efficiency, eddy current loss, curve fitting modeling

DOI: 10.3233/JAE-201576

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 66, no. 3, pp. 425-443, 2021

Authors: Xu, Dongying | Bao, Xiaohua | Xu, Wei | Xu, Yixiang

Article Type: Research Article

Abstract: Synchronous Reluctance Motors (SynRMs) have been widely used in some industrial fields because of their attractive characteristics, such as high efficiency, low cost, and simple structure. In order to reduce the torque ripple of the SynRMs, a non-parametric model is usually used to optimize the rotor structure. However, the conventional method has the problems of the low-accuracy and poor generalization ability. In this paper, an optimization method of the rotor structure is proposed to reduce the torque ripple by utilizing the deep learning algorithm. Firstly, the sample data of the relationship between the rotor structural parameters and torque ripple are …obtained with the finite element analysis (FEA). The fast calculation model is established by the deep neural network (DNN). Then, with the goal of not weakening the torque density and minimizing the torque ripple, the immune clone algorithm (ICA) is utilized to optimize the structural parameters of the rotor at different operating points. Finally, the correctness and validity of the method are verified by the simulation analysis. It is concluded that the accuracy of the model established by DNN is acceptable. The proposed method can significantly reduce the torque ripple and increase the torque density. Show more

Keywords: Deep neural network (DNN), immune clone algorithm (ICA), synchronous reluctance motor (SynRM), torque ripple

DOI: 10.3233/JAE-201577

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 66, no. 3, pp. 445-459, 2021

Authors: Fan, Xinyu | Yin, Jie | Su, Shichuan | Pang, Hongyan | Song, Yindong

Article Type: Research Article

Abstract: Electromagnetic valve train (EMVT) can realize independent, real-time and continuous valve motion regulation through the precise motion servo control, which has great potential to improve the efficiency of internal combustion engines. As an electromechanical integration device, EMVT is driven by electric energy, and the loss distribution is complex and changeable under different service conditions. Especially when the EMVT is used in exhaust system, the high gas pressure after combustion will increase the energy loss and operating temperature significantly. In order to improve the device performance, this study analyses the loss distribution and variation law of EMVT under different service conditions. …First, the flux density is obtained by the 3D finite element simulation. In combination with the valve train dynamic Matlab/Simulink model, the copper loss and iron loss of EMVT under typical conditions are explored in detail. Then, the influence of the motion parameters (transition time) and condition parameters (gas pressure) on EMVT’s loss are calculated and analyzed significantly. In the end, the accuracy of the loss models and analysis results is verified by the experiment based on linear load simulator. Show more

Keywords: Electromagnetic linear actuator, loss distribution, camless engine, gas pressure disturbance, dynamic analysis

DOI: 10.3233/JAE-201589

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 66, no. 3, pp. 461-473, 2021

Authors: Jun, Zhu | Zhenyi, Zhang | Di, Cao | Shaotong, Du | Xiangwei, Guo | Penghui, Liu | Ming, Yang

Article Type: Research Article

Abstract: Aiming at the “light wind start, light wind power generation” of vertical axis wind turbine, a new T-shaped radial passive magnetic bearing with high suspension characteristics is proposed. Passive magnetic bearings used in vertical axis wind turbines usually have small bearing capacity and difficult magnetization. The new T-shaped radial PMB can improve the radial bearing capacity, and the three magnetic rings all adopt simple axial magnetization. The new T-shaped radial PMB is combined with mechanical auxiliary bearing to form the suspension system of wind turbine. In the stable state, the suspension system can realize radial and axial stable suspension. The …structure and working principle of the suspension system are briefly described. Through the finite element simulation, the characteristics of the new T-shaped radial PMB, the traditional double-ring PMB and the T-shaped PMBs are compared. Taking the high bearing capacity and high stiffness of the new T-shaped radial PMB as the optimization objective, the multi-objective optimization of the new T-shaped radial PMB was carried out by changing its geometric parameters (inner diameter, magnetization length and air gap). The research results show that: Under the same bearing capacity, the volume of the new T-shaped radial PMB is reduced by about 78.64%. Under the same volume, its bearing capacity increased by about 30.7%, and its stiffness increased by about 96.1%. After optimization, its radial bearing capacity increased to 101.38 N, and its stiffness increased to 202.76 N/mm. Show more

Keywords: High bearing capacity, high stiffness, new T-shaped radial PMB, multi objective optimization

DOI: 10.3233/JAE-201591

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 66, no. 3, pp. 475-489, 2021

Authors: Li, Xiaoning | Wang, Xiaoyuan | Gao, Peng | Gu, Yuxi

Article Type: Research Article

Abstract: The disc coreless permanent magnet synchronous machine (PMSM) has a special coreless structure. This kind of PMSM has very low inductance, which is referred to as the low-inductance PMSM(LIPMSM) in this paper. The LIPMSM offers many advantages to drive systems. However, the current fluctuates strongly when driven by general converters, which makes the LIPMSM difficult to be popularized into modern drive systems. To tackle the above problems, a converter with output inductance is used. The influences of the inductance on the performance of the LIPMSM system are analysed, including current fluctuations, the maximum speed without flux weakening and the current …response time. Based on above analyses, a method of obtaining the optimal inductance is proposed to obtain the optimal inductance simply and efficiently. The method has been verified through simulations and experiments. The system cannot work due to the huge current fluctuations when driven by the general converter. By using the converter with the optimal inductance, the current fluctuations have been reduced to 2 A. The experimental LIPMSM can reach 11000 rpm with very short response time of the current. Therefore, the LIPMSM system performance can been improved significantly and meet the requirements by using the converter with the optimal inductance. Show more

Keywords: Disc coreless permanent magnet synchronous machine (DCPMSM), low inductance, current fluctuations, maximum speed, optimal inductance

DOI: 10.3233/JAE-201605

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 66, no. 3, pp. 491-508, 2021

Authors: Zhang, Yujiao | Chen, Yanran | Li, Houxu | Huang, Xiongfeng | Yan, Cheng

Article Type: Research Article

Abstract: The live working paths for equipotential operators in the hanging basket method is determined by minimum safety values of various clearances stipulated in regulations. However, the optimization of the safety path planning by the complex gaps is scarce. In this paper, an optimization method for path planning is proposed based on ant colony algorithm. Grid model is established to partition the operation area into different calculation districts, in which key parameters are grid data and obstacle grids. Grid data are the maximum value of the electric field strength on the body surface, calculated by the finite element model. And obstacle …grids are grids that dissatisfy the requirements of complex gaps and their data are larger than the air breakdown field strength. Then ant colony algorithm is employed to search for the best operation path with the minimum working distance and the minimum electric field strength value. After that, an application case is illustrated to demonstrate the optimizing processes. At last, the shock U50 test and power frequency corona discharge test are implemented to verify the safety of the optimized path. Therefore, the path obtained by the proposed method scientifically and effectively shortens the distance of the hanging basket method. Show more

Keywords: Hanging basket method, electric field calculation, finite element method, grid-ant colony algorithm

DOI: 10.3233/JAE-201614

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 66, no. 3, pp. 509-524, 2021

Authors: Fang, Hong Wei | Wang, Yu

Article Type: Research Article

Abstract: The magnetic gear integrated permanent magnet synchronous generator (MG-PMSG) can reduce the acoustic noise and mechanical loss, which are caused by the mechanical gear box. It also has the merits of increasing efficiency and reducing system volume when it is used for wave energy conversion system. In this paper, an improved bat algorithm (BA) based on velocity weighting factor is proposed. The improved BA is applied for the optimization design of permanent magnet (PM) to reduce the cogging torque of MG-PMSG. The numerical model is constructed by response surface methodology (RSM). The influences of key pole shape parameters on cogging …torque were investigated, including the eccentric distance, the pole-arc coefficient and the permanent magnet thickness. A global optimization design is then carried out by using the improved BA, so that the magnet dimensions corresponding to the optimal cogging torque are obtained. Finally, the performances of the MG-PMSG with the optimized permanent magnet are analyzed by finite element method. Results show that cogging torque, steady torque ripple and back electromotive force (EMF) waveform distortion of the optimized MG-PMSG are reduced. Show more

Keywords: Magnetic gear, wave energy conversion, cogging torque, bat algorithm, response surface methodology

DOI: 10.3233/JAE-201615

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 66, no. 3, pp. 525-542, 2021