Multi-objective Optimization and Design of Flux-concentrating Permanent Magnet In-wheel Motor

In-wheel drive system puts forward more demands on the space size and speed of the motor due to integration with the two-stage planetary reducer. First, a new flux-concentrating permanent magnet (PM) in-wheel motor is proposed to improve the torque density and flux-weakening range. In addition, the influence law of PM rotor key parameters on torque density, flux-weakening ability and rotor strength is analyzed, and the motor’s initial optimization objectives are determined. Furthermore, the surrogate model of torque density, characteristic current, and rotor stress is built based on finite element method (FEM) and response surface method (RSM), and the improved cuckoo search (CS) algorithm is applied to multi-objective optimization design. The electromagnetic and mechanical performance of the initial and optimal motor are compared and analyzed. Finally, a 75kW PM in-wheel motor prototype is manufactured, and the feasibility and effectiveness of the proposed multi-objective optimization method are verified by the tested results. © 2024 Chin.Soc.for Elec.Eng.