离散Halbach永磁电动机气隙磁通密度特点及其空载电动势波形优化

利用离散Halbach阵列气隙磁通密度分布特点,合理选择电动机转子结构参数,对发挥永磁体潜力至关重要。文中采用电磁场有限元数值计算方法,揭示离散Halbach阵列气隙磁通密度的谐波和基波与每极磁体数、磁体厚度以及极对数之间的变化规律。并以此为依据设计样机一台,实验结果验证了有限元模型的正确性。同时进一步以样机的结构参数为基础,对反电动势进行优化,提出一种削弱集中非叠绕组结构空载电动势谐波的方法,为离散Halbach阵列集中非叠绕组电机设计提供参考。

Features of Air-Gap Flux Density in Segmented Halbach Permanent Magnet Synchronous Motor and Its No-Load EMF Waveform Optimization

Magnetic field distribution of segmented Halbach array is influenced by the rotor parameters. So the rational choice of them is very critical to realize the high performance of permanent motor. This paper discusses the rule of the air-gap flux density varying with the magnet number per pole, the thickness of magnet and the pole number by static-steady electromagnetic field theory. A prototype motor is also designed according to the theoretical analysis, and the experimental results verify the finite element analysis model well. Non-overlapping concentrated windings are equipped in the prototype motor and the no-load electromotive force (EMF) of the prototype motor contains a great quantity of harmonics. A novel method is proposed in order to reduce the harmonic of no-load EMF waveform induced in non-overlapping concentrated windings. The rule and the method presented in this paper provide reference for study and design the segmented Halbach array and non-overlapping concentrated windings.