The Analysis and Calculation of Load Radial Electromagnetic Force of the Interior Permanent Magnet Synchronous Machine

In this paper, the combination of finite element and magneto motive force magnetic conductance methods is used to calculate the load radial electromagnetic force. Firstly, based on the principle of frozen permeability (FP), this paper presents a new d-axis magnetic permeability model, and the expression of the radial flux density in the air gap is proposed by this model. Furthermore, the radial electromagnetic force with different orders and frequencies at load situation are calculated by the interaction of different order harmonics in radial flux density. Finally, for the force wave reduction, the optimal pole arc coefficient is calculated by the analytic method and verified by finite element method.