Abstract: On the basis of considering the electric motor vibration, a time domain vertical dynamics model of the electric vehicle with 11 DOF is built, and the road roughness input model and the numerical method are given. Aiming at an electric passenger vehicle, the basic characteristics of the typical vehicle dynamics responses under the condition of the impulse and random road roughness inputs are calculated, the influence of the different mount stiffness, damping and motor mass on the motor and the vehicle vibration is analyzed under the condition of the impulse input. The results show that the proposed model is able to analyze not only the vehicle ride, but also the motor vibration and its influence on the vehicle ride. Under the impulse input, the variation of the electric motor parameters has little impact on the vehicle ride, but has obviously effect on the motor vibration. The higher mount stiffness and damping, and the lower motor mass, the smaller the motor vibration will be.

Key words: electric vehicle, vehicle ride, electric motor vibration, mount, impulse input, random road roughness