Design and analysis of high power density permanent magnet-assisted synchronous reluctance motor

Permanent magnet-assisted synchronous reluctance motor (PMSRM) has been widely used in many fields due to their advantages of less permanent magnets and low cost. However, the permanent magnet torque and reluctance torque of the traditional PMSRM reach their maximum values at different current angles. Therefore, the utilization ratio of the total torque to each torque component is low, which leads to the low power density of the PMSRM. To solve this problem, a new rotor structure suitable for PMSRM is proposed in this paper. The rotor can improve the total torque by increasing the maximum value of permanent magnet torque and the utilization rate of total torque to each torque component. Thus, the power density of the motor is effectively improved. In order to realize the matching design of each parameter in the proposed rotor structure, the Taguchi method is used to optimize the design, and the influence of each optimization variable on torque and torque ripple is analyzed. The finite element simulation analysis method is used to establish the electromagnetic simulation model of the traditional structure, the new structure proposed and the optimized structure of the new structure by Maxwell simulation software. The simulation results show that the proposed new rotor structure not only effectively improves the torque density, but also effectively reduces the torque ripple.