表贴式永磁电机偏心削极技术的优化方法

Optimization Method of Eccentricity Cutting Technology for Surface-mounted Permanent Magnet Motor

偏心削极是表贴式永磁电机常用的削极方式,可以用来优化电机的气隙磁场正弦度,改善电机性能。由于偏心削极没有唯一解,本文针对偏心削极的寻优问题,提出了通过改变削极厚度和极弧系数对偏心削极寻优的方法。采用有限元法对偏心削极的优化效果进行寻优,将削极厚度和极弧系数作为两个变量,分析对比每种偏心磁极的气隙磁密波形以及气隙磁密谐波畸变率。选取其中谐波畸变率最小的削极厚度和极弧系数参数组合作为最优解,此时气隙磁场正弦度最优,达到了改善永磁电机性能的目的。

Eccentric pole cutting is a commonly used method of pole-cutting for surface mount permanent magnet motors, which can optimize the sinusoid of the air gap magnetic field of the motor and improve the performance of the motor. Since there is no unique solution for the eccentric cutting, for the optimization problem of eccentric cutting, a method for optimizing the eccentric cutting by changing the thickness of the pole and the arc coefficient is proposed. The Finite Element Method is used to optimize the effect of the eccentricity. The thickness and the polar arc coefficient are used as two variables to analyze and compare the air gap magnetic density waveform of each eccentric magnetic pole and the air gap harmonic distortion rate. The combination of the minimum thickness and the polar arc coefficient of the harmonic distortion rate is selected as the optimal solution. At this time, the sinusoidality of the air gap magnetic field is optimal, which improves the performance of the permanent magnet motor.