Research on cogging torque of disk motor based on stator structure optimization

In order to weaken the cogging torque of disk permanent magnet motors, two structural optimization methods of stator offset and unequal stator boot are proposed. The cogging torque formula of axial motor is derived by energy method and Fourier decomposition, and the minimum cogging torque of the original model is obtained by optimizing the width of the stator groove. Then, the offset angle of the stator offset structure is obtained by calculating and finite element analysis. Finally, through theoretical analysis and simulation calculation, the expansion width of the stator gear boots based on the minimum cogging torque is obtained, and the unequal stator gear boots structure can make the stator’s upper and lower cogging torque cancel each other. The comparison results show that the unequal stator boot structure has the best effect on the reduction of cogging torque. When the expansion width is 1.2, the cogging torque is reduced by 71%.