正弦极宽调制式永磁电机的磁场分析与实验

Magnetic field analysis and experiment of sinusoidal pole width modulation permanent magnet motor

为提高传统表面式永磁电机气隙磁场的正弦程度,降低永磁电机的谐波影响,提高表面式永磁电机的效率与力能指标,提出一种正弦磁极调制式的永磁电机转子结构。转子铁心表面磁极是由若干小磁块阵列构成的,阵列中磁块的宽度、高度及磁块之间的间隔符合一种调制关系,合理设置转子永磁替的结构和位置使其产生的气隙磁场波形更加接近正弦波。通过电磁场有限元分析和样机实验检测电机内气隙磁场波形,实验表明气隙磁场正弦性畸变率实际降低了24.45%,说明本文提出改善表面式永磁电机气隙磁场波形正弦化程度的正弦极宽调制方法和结构正确有效。

In order to improve the sinusoidal waveform of surface-mounted permanent magnet motor,cut down its harmonic component and increase its efficiency and power index,this paper put forward a sinusoidal magnetic pole modulation permanent magnet motor.Rotor iron core surface was composed of a number of small arrayal magnetic blocks.Its width height and interval between arrayed magnets met a modulation relationship.Air-gap magnet field waveform was generated more closely to sinusoidal waveform by setting the structure and location of the rotor and poles reasonably.At the same time,the magnetic field analysis was carried out by ANSOFT program.Then,the results are verified that sinusoidal air gap magnetic field distortion is actually lowered of 24.45%.It shows that the proposed method of improving PMSM magnetic field sinusoidal waveform is effective and correct.