轴向磁通永磁电机空载气隙磁场建模分析

Analysis and Modeling for Open Circuit Air Gap Magnetic Field Prediction in Axial Flux Permanent Magnet Machines

针对轴向磁通永磁电机有限元仿真较为耗时的问题,建立了轴向磁通永磁电机空载气隙磁场解析模型。提出通过建立虚拟等效直线电机模型用以计算气隙磁场端部效应修正函数,使得空载气隙磁场模型得以整体解析化。给出了气隙磁导函数相应的替代函数,并对此替代函数进行了傅里叶级数转换,使空载气隙磁场函数具有形式上统一的解析表达式,便于计算机编程实现。对空载气隙磁密、空载反电动势和齿槽转矩进行了解析计算,与有限元计算结果对比,验证了该文所建立的空载气隙磁场模型的正确性和可行性,可以作为轴向磁通永磁电机设计人员参考使用。

To solve the problem of the simulations for a axial flux permanent magnet machines by 3 D finite element method is time-consuming, an open circuit air gap magnetic field analytical model was built for axial flux permanent magnet machines. A virtual equivalent linear machines model was built in order to calculate the end effect correction function of air gap magnetic field, which accomplishes the analysis of open-circuit air gap magnetic field model completely. As the replace function of air gap permanence function and its Fourier series were given in this paper, the function of open-circuit air gap magnetic field gained a unified form, thus the program difficulty for open circuit air gap magnetic field will be reduced correspondingly. The calculations of open-circuit air gap magnetic field, back EMF and cogging torque were conducted by finite element method and analytical method respectively, the outcome proves that the open circuit air gap magnetic field analytical model in this paper is correct and practical. Therefore, the analytical model can be used as a reference for the researchers who design axial flux permanent magnet machines.