scholarly journals Multi-Objective Optimization of the Halbach Array Permanent Magnet Spherical Motor Based on Support Vector Machine

Energies ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 5704
Author(s):  
Hongfeng Li ◽  
Lifeng Cui ◽  
Zigang Ma ◽  
Bin Li
Keyword(s):  
Magnetic Field ◽  
Support Vector Machine ◽  
Air Gap ◽  
Moment Of Inertia ◽  
Support Vector ◽  
Spherical Motor ◽  
Halbach Array ◽  
Waveform Distortion ◽  
Air Gap Magnetic Field ◽  
Distortion Rate

The fundamental harmonic amplitude and waveform distortion rate of the air-gap flux density directly affect the performance of a permanent magnet spherical motor (PMSM). Therefore, in the paper, the axial air-gap magnetic field including the end leakage of the Halbach array PMSM is analyzed and optimized. In order to reduce the calculation time of the objective function, the air gap magnetic field model adopts a non-linear regression model based on support vector machine (SVM). At the same time, the improved grid search (GS) algorithm is used to optimize the parameters of SVM model, which improves the efficiency and accuracy of parameter optimization. Considering the influence of moment of inertia on the dynamic response of the motor, the moment of inertia of the PMSM is calculated. This paper takes the air gap magnetic density fundamental wave amplitude, waveform distortion rate and rotor moment of inertia as the optimization objectives. The particle swarm optimization (PSO) algorithm is used to optimize the motor structure with multiple objectives. The optimal structure design of the PMSM is selected from all of non-dominated solutions by the technique for order preference by similarity to an ideal solution (TOPSIS). The performance of the motor before and after the optimization is analyzed by the method of finite element (FEM) and experimental verification. The results verify the effectiveness and efficiency of the optimization method for the optimal structure designing of the complex PMSM.

Air-Gap Magnetic Field Optimization to Reduce Losses in High Speed Bearingless Permanent Magnet Synchronous Motor

2013 ◽  
Vol 387 ◽  
pp. 360-364
Author(s):  
Tao Zhang ◽  
Hong Yun Jia ◽  
Hui Ping Zhang ◽  
Jian Xiang Ji
Keyword(s):  
Magnetic Field ◽  
Permanent Magnet ◽  
High Speed ◽  
Permanent Magnet Synchronous Motor ◽  
Magnetic Bearing ◽  
Air Gap ◽  
Time Stepping ◽  
Bearing Unit ◽  
Halbach Array ◽  
Air Gap Magnetic Field

In this paper, the high speed motor hybrids with a radial-axial 3 degree of freedom hybrid magnetic bearing unit and BPMSM unit is proposed. The radial suspension force and magnetic field distributions with different magnetized mode are calculated. The losses are calculated and compared using time-stepping finite element method. The research results have shown that the high-speed BPMSM with Halbach array permanent magnet rotor has sinusoidal air-gap magnetic field, minimum losses.

Torque ripple optimization for synchronous reluctance motors based on a virtual permanent magnet harmonic machine model

2021 ◽  
Vol 67 (3) ◽  
pp. 327-338
Author(s):  
Yixiang Xu ◽  
Chong Di ◽  
Xiaohua Bao ◽  
Dongying Xu
Keyword(s):  
Magnetic Field ◽  
Permanent Magnet ◽  
Torque Ripple ◽  
Air Gap ◽  
Analysis Model ◽  
Machine Model ◽  
Asymmetric Rotor ◽  
Rotor Flux ◽  
Air Gap Magnetic Field ◽  
Intermediate Variables

The torque ripple is affected by both the stator and the rotor magnetic field harmonics. In synchronous reluctance motors (SynRM), there are only rotor permeance harmonics existing on the rotor side for the absence of the rotor windings. Since the asymmetric rotor flux barriers are widely applied in the SynRM rotor, it is difficult to calculate the rotor permeance accurately by the analytical method. In this article, the effects of the rotor permeance harmonics on the air-gap magnetic field are studied by a virtual permanent magnet harmonic machine (VPMHM), which is a finite-element (FE) based magnetostatic analysis model. The air-gap flux density harmonics produced by the SynRM rotor are extracted from the VPMHM model and used as the intermediate variables for the torque ripple optimization. The proposed method does not need to solve the transient process of motor motion. Hence, the time of the optimization process can be significantly shortened. Finally, a full electric cycle is simulated by dynamic FE simulation, and the torque ripple is proved to be effectively reduced.

Electromagnetic Field Analysis of Hybrid Excitation Vehicle Generator with Low Voltage and High Current

2012 ◽  
Vol 229-231 ◽  
pp. 945-948
Author(s):  
Yue Jun An ◽  
Li Min Zhou ◽  
Li Ping Xue ◽  
Yong Li
Keyword(s):  
Magnetic Field ◽  
Permanent Magnet ◽  
Permanent Magnets ◽  
Low Voltage ◽  
Air Gap ◽  
Installation Space ◽  
Velocity Variation ◽  
High Current ◽  
Hybrid Excitation ◽  
Air Gap Magnetic Field

In order to further improve the power supply system reliability of low voltage high current vehicle generator, hybrid excitation is used and the permanent magnets are added between the main magnetic poles body and pole shoes. Aiming at reply the problem of limited installation space, the asymmetric pole structure, non-uniform commutating pole, single wave windings playing a role of the pressure line and oblique brush etc are investigated for improving commutation. This paper researched on the distribution of the flux line, the waveform of the air gap magnetic field, and analysis inner magnetic field at the loading by hybrid excitation and no loading by permanent magnet excitation alone respectively with the method of finite element. The results reveal that the magnetic field established by several excitation systems is still symmetric and uniform although the asymmetric structure, so it ensures the provision of suitable medium space for mechanical and electrical energy conversion. By comparing the permanent magnets excitation alone and hybrid excitation in a generator magnetic field distribution and air gap magnetic field waveform, the permanent magnet excitation and electricity excitation realized the superposition of magnetic field, and common establish main generator magnetic field. Hybrid excitation also reduces the current density of excitation coils and improves the heat dissipating performance compared with electrically excited alone. Through the performance analysis of the hybrid excitation, the output voltage waveform is very stable. The curve of auxiliary excitation current along with velocity variation provide important basis for excitation control devices and the development of control algorithm. It will help to improve the stability, reliability and security of the generator, the results can provide key technical support to the development of low-voltage high-current hybrid excitation vehicle generator.

Sign in / Sign up

Export Citation Format

Share Document