Research on the Method of Reducing Cogging Force of Vernier Motor

In this paper, the method of reducing the cogging force of permanent magnet vernier motor(PMVM) by auxiliary slots in the top of stator teeth is studied. Fourier decomposition of the analytical formula of the cogging force is carried out, the finite element software ANSYS Maxwell is used to model and simulate the auxiliary slot structure, and the peak values of cogging force at different width and depth of the auxiliary slots are calculated, and the influence principles of the auxiliary slots on the cogging force are obtained. The total harmonic distortion(THD) of air gap magnetic field, THD of back electromotive force and torque ripple of the motor with adopting auxiliary slots are calculated. The results show that reasonable number and size of auxiliary slots can weaken the slot force and restrain the torque fluctuation.