A method of reducing cogging torque for IPMSM based on stator auxiliary slot

Abstract

Built-in permanent magnet synchronous motor (IPMSM) has short effective air gap and large torque ripple caused by cogging torque, resulting in speed fluctuation, vibration and noise and other problems. The mechanism of cogging torque generation is studied theoretically, and the method of cogging torque weakening based on stator opening auxiliary slot is presented. Taking the V+1 interior permanent magnet synchronous motor for example, the effects of the slot number, shape, slot width, depth and slot center line Angle of each stator tooth on the cogging torque were analyzed by ANSYS Maxwell finite element simulation software. The results show that when the slot number is two, the slot shape is rectangular, the slot width is 1.6mm, the slot depth is 1.1mm, and the position Angle is 1.2°, the cogging torque is reduced by 61.9% compared with that without slotting, and the weakening effect is the best and the performance of the motor is verified to be improved.