永磁无刷直流电机空载气隙磁场和绕组反电势的解析计算

该文利用许－克变换构造了考虑齿槽效应的气隙相对比磁导函数，该气隙相对比磁导函数反映了齿槽效应对气隙磁场分布的影响，且这种影响的程度随气隙中的径向位置而变化，在忽略铁心饱和的情况下，结合偏微分方程的解析算法，提出了一种考虑齿槽效应的永磁无刷直流电机空载气隙磁场分布和相绕相反电动势的解析计算方法，计算结果与二维有限元计算结果对比，其计算波形和大小吻合很好，证明此方法是正确的、可靠的、为永磁无刷直流电机优化设计和性能分析提供了基本分析手段。

ANALYTICAL CALCULATION OF NO-LOAD AIR-GAP MAGNETIC FIELD AND BACK ELECTROMOTIVE FORCE IN BRUSHLESS DC MOTOR

Based on the method of the Schwarz-Christoffel transformation, this paper presents an air-gap relative specific permeance function , considering the slots in stator core. This function reflects the effect of the slots in stator core on the no-load air-gap magnetic field. In fact, the effect is variant with the air-gap radius. Utilizing the analytical method of partial differential equation and neglecting the saturation of the core, an analytical method for the distribution of no-load air-gap magnetic field and back EMF in the phase windings is proposed ,which is suitable for permanent magnet brushless DC motors. Compared with the result derived from the 2D finite element method, the proposed method is confirmed. The presented work may function as a basic tool for optimizing design and performance analysis of permanent magnet brushless DC motors.