摘要：对基于90° Halbach阵列的盘式无铁心永磁同步电机的磁钢进行形状优化，以改善电机的气隙磁密波形。分析了电机的结构和空载电磁场，在此基础上采用改变永磁体边缘形状方法将90°Halbach型永磁体阵列优化为内圆型、外圆型和削角型3种，并利用有限元法分析不同永磁体形状对气隙磁密波形的正弦性和基波幅值的影响。分析表明优化后的90°Halbach 型盘式无铁心永磁同步电机能够获得和45°Halbach 型电机基本相同的气隙磁密，并且在永磁体充磁、加工和安装定位等方面要优于45°Halbach 型电机。3种永磁体形状优化中内圆型永磁体的优化效果最佳。

关键词：盘式无铁心；Halbach；形状优化；气隙磁通密度；有限元分析
Abstract: The paper investigated the magnet optimization of a disc coreless permanent magnet synchronous motor (PMSM) which was based on 90° Halbach array to improve its waveform of air-gap flux density. The structural characteristics and the electromagnetic field of the motor were studied firstly. The shape of the magnet was optimized by considering different magnet shapes including rounding out shape, rounded inside shape, and rectangular chamfered shape. The effects of different magnet shapes on the waveform of flux density were analyzed with FEA, and the optimal parameters of the magnet were obtained. It is shown disc coreless PMSM with optimized 90° Halbach array can get sinusoidal air-gap flux density as same as the motor with 45° Halbach array. It has advantages in permanent magnet magnetization, processing and location. Rounding out shape is the best one of three shape optimization.

Key words: disc coreless; Halbach; shape optimization; air-gap flux density; FEA