Multifunctional Optimal Design of Axial-Flux Permanent Magnet Wheel Motors for Light Electric Vehicles

This paper presents a systematic approach of optimal design for an axial-flux permanent magnet wheel motor to have high torque density for light electric vehicles. First, the winding type and the numbers of slots and poles are determined at the stage of preliminary design. A magnetic circuit model with an effective air-gap distribution is then established for sensitivity analysis and multifunctional optimization. Finally, the finite element analysis is performed for verifying and refining the motor with the best torque density to fulfill design specifications. The theory of maximum torque per ampere is also applied to estimate the torque and power versus speed curves of the resulting wheel motor before it is fabricated.