Design of direct-drive axial flux permanent magnet in-wheel machine for electric vehicle

Abstract

Indirect-drive electric vehicle system will improve the overall reliability and efficiency due to elimination of reduction gear and the differential gear. The paper discusses the design of direct-drive axial flux permanent magnet in-wheel machine for electric vehicle in order to achieve a wide speed range operation and low cogging torque. Fractional-slot winding and wedges made from soft magnetic composition material are adopted for increasing the value of the inductance, so as to improve the AFPM flux-weakening capability. Design results as well as simulation results verify the validation of the proposed method.