车用永磁同步电机(PMSM)的电磁噪声是新能源汽车噪声的主要来源，直接影响整车的振动噪声特性。作用于电机定子结构的低阶径向电磁力是电机电磁噪声的主要原因，以1台额定功率35 kW的新能源车用PMSM为研究对象，提出一种转子外缘开辅助槽的优化方案以降低电机的振动噪声，通过对辅助槽的多个参数进行多变量寻优确定最优的参数值。采用有限元法对采用辅助槽前后的电机进行振动噪声的仿真对比，最后通过样机的振动噪声试验验证了理论研究的正确性，实测样机通过转子开辅助槽的优化方案使电机振动加速度幅值降低了2g，噪声降低了4 dB。

The electromagnetic noise of permanent magnet synchronous motor (PMSM) for vehicles is the main source of new energy vehicle noise, which directly affects the vibration and noise characteristics of the vehicle. The low-order radial electromagnetic force acting on the stator structure of the motor is the main reason for the electromagnetic noise of the motor. Taking a PMSM for new energy vehicle with a rated power of 35 kW as the research object, an optimization method with auxiliary slots on the outer edge of the rotor is proposed to reduce the vibration and noise of the motor. The optimal parameter values are determined by multivariate optimization of multiple parameters of the auxiliary slot. The finite element method is used to compare the vibration and noise of the motor with and without the auxiliary slots. Finally, the correctness of the method is verified by the vibration and noise experiment of the prototype. Through the optimization of the rotor with auxiliary slots, the amplitude of the motor vibration acceleration is reduced by 2g and the noise is reduced by 4 dB.