Topology Optimization of a Surface Permanent Magnet Motor With High Torque Density

This article introduces a topology optimization method for a surface permanent magnet (SPM) motor with high torque density suitable for air mobility. The proposed method can be used to determine the material distribution and magnetization direction in PMs to maximize the torque density at a constant current. The torque performance of the optimized motor is superior to that of a conventional motor with a Halbach array, whose magnetization varies linearly along the circumferential direction. The novel optimized motor has a triangular magnetic material on the rotor surface and an air region inside the rotor.