Study on vibration and noise of fractional slot IPMSM for electric vehicle based on multi-physical field coupling method

Electric vehicles (EVs) have attracted growing interests worldwide because of their advantages of zero emission, low noise and energy saving. Fractional slot interior permanent magnet synchronous motors (IPMSMs) are attractive for EV applications due to their high power density and high efficiency. However, the fractional-slot IPMSMs normally suffer large vibration noise induced by the abundant harmonics in the airgap magnetic field. In this paper, the radial electromagnetic force and the mode of the motor are analyzed based on finite element method (FEM), respectively. Besides, the vibration and noise of the fractional slot IPMSM are studied by the multi-physical field coupling simulation. Finally, the prototype is manufactured and tested to verify the correctness of the theoretical analyses.