Electromagnetic and NVH Analysis of PMSM with Eccentricity and Rotor Magnetization Variations

Permanent magnet synchronous motors (PMSM) are among the most promising motors in electric vehicles due to their high torque density and efficiency. This paper is devoted to detailed electromagnetic investigations of permanent magnet synchronous motor, accounting for specific rotor eccentricity and uneven magnetization. A series of simulations are performed for a 90 HP interior PMSM to investigate the changes in the radial and tangential forces when the rotor is perfectly aligned or with static, dynamic, and mixed eccentricities. Besides, the influence of uneven magnetization due to manufacturing, demagnetization, and magnet deterioration is discussed. The forces are then used to load a vibro-acoustic model to evaluate the impact on the noise, vibration, and harshness (NVH) performance and predict the radiated sound power level for the different conditions.