Multi-Objective Optimization of Permanent Magnet Assisted Synchronous Reluctance Motor

Permanent Magnet Assisted Synchronous Magnetic Reluctance Motor (PMaSynRM) exhibits lower efficiency and torque density. This paper focuses on optimizing the efficiency and average output torque of PMaSynRM, emphasizing the impact of permanent magnet quantity and end angles of the flux barrier on motor performance. The analysis determines the rotor's flux barrier shape, number of layers, and optimal flux barrier ratio of the rotor. Subsequently, the Taguchi method conducts sensitivity analysis on permanent magnet width at different positions. Combining the end angles of the flux barrier, a Kriging surrogate model of PMaSynRM is established using Latin hypercube sampling. The model's accuracy is improved through additional point selection based on the expected improvement criterion. A multi-objective particle swarm optimization algorithm is then employed to obtain Pareto frontiers related to motor efficiency and average output torque. After optimization, while maintaining constant output torque, magnet usage is reduced by 22%, torque contribution per unit of magnet increases by 29%, and motor efficiency improves by 2.7%. Finally, based on the optimization results, a prototype is fabricated and experimentally tested, demonstrating an efficiency of 94.4% at the rated operating point and validating the accuracy of the optimized design.