基于非线性混合模型的模块组合式永磁电机磁场解析

Analytical Prediction of Magnetic Field in Modular Combined Permanent Magnet Motor by a Nonlinear Hybrid Model

为准确计算模块组合式永磁电机的电磁性能,该文建立了一种子域法和等效磁网络法相结合的非线性混合磁场解析模型。通过在子域模型定子槽边界施加等效电流片,非线性磁场解析模型可等效成为考虑了饱和效应的线性磁场解析模型。改进子域解析模型边界上的等效电流密度在等效磁网络模型中计算,等效磁网络中的磁通源需要在子域法中计算,因此需采用迭代算法进行求解。等效磁网络模型中考虑了相邻定子模块之间的装配气隙。基于该非线性混合磁场解析模型计算了电机的气隙磁通密度、空载反电动势和电磁转矩,并重点分析模块组合式永磁电机在不对称运行状态下的电磁特性。最后通过有限元仿真结果和样机实验数据验证了该非线性混合磁场解析模型的正确性。

This paper proposes a nonlinear subdomain and equivalent magnetic network hybrid analytical model for electromagnetic performance calculation in modular combined permanent-magnet machines(MCPMM).The nonlinear analytical model can be transformed into a linear subdomain model considering saturation effect with equivalent current densities on the boundary of the slots.The values of equivalent current densities are obtained by the equivalent magnetic network and used as boundary conditions in subdomain model,and the flux sources flowing to the equivalent magnetic network are calculated by the subdomain model.An iteration process is needed between the two analytical models.The air gap between adjacent modules is considered in the equivalent magnetic network model.The nonlinear hybrid model can accurately calculate the air gap flux density,no-load back EMF and torque.The electromagnetic characteristics of modular permanent magnet motor under asymmetric conditions are analyzed.The finite element results and experimental test verify the proposed nonlinear analytical method.