Slot and Pole Ratio of Permanent Magnet Synchronous Motor for Cogging Torque and Torque Ripple Performance

This paper presents electromagnetic design and analysis of a electric vehicle(EV) motor used in e-Van. For EV traction motor, Noise vibration and harshness(NVH) performance is important for end-user. Motor is one of the main excitation source in EV. Motor slot and pole ratio design is critical point for cogging torque and torque ripple which are directed related to NVH. In this paper, we discuss four motors at similar output power and torque. Motor electromagnetic finite element analysis results show that different slot and pole ratio motors performance. Furthermore, design guideline for choosing better slot and pole ratio design and ripple reducing method is proposed. Finally, the real case study for NVH behavior improving is mentioned from the e-Van traction motor.