基于Halbach阵列磁钢的PMSM气隙磁密波形优化

Air-Gap Flux Density Waveform Optimization of PMSM Based on Halbach Array Magnet Steel

为了提高永磁同步电机(PMSM)气隙磁密波形的正弦性,降低谐波磁场对运行过程中的电机性能影响,提出一种基于极间隔断的每极三单片不均匀Halbach阵列磁钢,其中,每块磁钢均由位于磁钢中部的主极以及双侧紧密连接的辅极构成,以磁钢的主极占比、磁钢圆周角度占比、辅极充磁角度为变量,研究了以上变量对气隙磁密谐波畸变率的影响。为了得到最优的气隙磁密波形,采用正交试验方法对三个变量进行合理均匀的实验安排,利用有限元软件ANSYS Maxwell 2D仿真分析,形成初始样本数据,采用支持向量机(SVM)对样本数据进行拟合回归,并检验了拟合结果的精度,采用粒子群算法(PSO),将SVM的回归函数作为适应度函数,进行寻优,得到最优解。以一款48槽8极的PMSM为例,采用有限元分析软件进行仿真分析,结果表明,基于极间隔断的每极三单片不均匀Hlabach阵列磁钢能有效减低气隙磁密谐波畸变率,改善气隙磁密波形正弦性。

In order to improve the sinusoidal property of air-gap flux density waveform of permanent magnet synchronous motor(PMSM)and reduce the influence of harmonic magnetic field on the performance of PMSM in the process of operation,this paper proposes a three-chip nonuniform Halbach array magnet steel with interval between poles.Each magnet steel consists of the main pole in the middle of the magnet steel and the auxiliary poles tightly connected on both sides.Taking the main pole proportion of magnet steel,circumferential angle proportion of magnet steel and magnetization angle of auxiliary pole as variables,the influences of the above variables on the harmonic distortion rate of air-gap flux density are researched.In order to obtain the optimal waveform of air-gap magnetic density,the orthogonal experimental method is used to arrange the three variables reasonably and uniformly.The simulation and analysis are carried out by finite-element software ANSYS Maxwell 2 D to form the initial sample data.The sample data is fitted and regressed by support vector machine(SVM),and the accuracy of the fitting results is tested.Taking the regression function of SVM as the fitness function,the particle swarm optimization(PSO)is used to obtain the optimal solution.Taking a 48-slot 8-pole PMSM as an example,the finite-element analysis software is used to carry out simulation and analysis.The results show that three-chip nonuniform Halbach array magnet steel with interval between poles can effectively reduce the harmonic distortion rate of air-gap magnetic density and improve the sinusoidal waveform of air-gap magnetic density.