W型永磁电机转矩脉动分析与抑制方法

Torque Ripple Analysis and Suppression Method of W-type Permanent Magnet Synchronous Motor

针对永磁同步电机转矩脉动偏大时电机输出性能较差的问题,对W型永磁同步电机的转矩脉动进行详细分析并研究其抑制方法。首先利用等效磁路法与洛伦兹力定律,推导出电机转矩脉动解析式,基于解析式对W型磁极的位置参数进行优化,并利用有限元软件仿真验证;然后利用转子极面偏心的方法进一步削弱电机转矩脉动,并分析最优偏心距。研究表明,当W型磁极布置位置合适时,电机具有良好的输出特性;通过转子极面偏心,电机转矩脉动降低12%,齿槽转矩与气隙磁密谐波含量大幅降低,电机性能显著提升。

Aiming at the problem that the output performance of permanent magnet synchronous motor(PMSM)is poor when the torque ripple is too large,the torque ripple of W-type PMSM was analyzed in detail and its suppression method had been studied.Firstly,the equivalent magnetic circuit method and Lorentz force law were used to derive the analytical formula of the motor torque ripple.Based on the analytical formula,the position parameters of the W-shaped magnetic pole were optimized and verified by finite element simulation.Then the rotor pole eccentricity method was used to further weaken the torque ripple and the optimal eccentricity was analyzed.The results show that the motor has good output characteristics when the W-type magnetic poles are properly arranged.By means of rotor pole eccentricity,the motor torque pulsation is reduced by 12%,the cog torque and air gap magneto-dense harmonic content are significantly reduced,and the motor performance is distinctly improved.