Multi-Objective Optimization Design of a Segmented Asymmetric V-Type Interior Permanent Magnet Synchronous Motor

Abstract

A segmented asymmetric V-type permanent magnet structure is proposed to address the issues of high output torque ripple and large cogging torque in traditional permanent magnet synchronous motors. First, the relationship between the pole-span angles of the segmented asymmetric V-type permanent magnet structure and the output torque, torque ripple, and cogging torque is investigated. Then, the rationality of the segmented asymmetric V-type permanent magnet structure and the correctness of the theoretical derivation are verified by the finite-element simulation. Subsequently, with the optimization objectives of increasing the average output torque of the motor, reducing the torque ripple, and decreasing the cogging torque, the optimal pole-span angle combination of the motor is determined by using the Pareto frontier distribution and the weight analysis method. The effectiveness of the optimized design is finally verified by the finite-element simulation and prototype tests. The results reveal that the segmented asymmetric V-type permanent magnet structure can ensure ample output torque while having low cogging torque and torque ripple in output characteristics.