Influences Analysis of In-wheel Motor on EV Vibration Performance

To analyse the influence of the increased unsprung mass on electric vehicle vibration performance as in-wheel motor embedded within the hub, Using one-quarter vehicle system with two degree-of-freedom, the vibration model of in-wheel motor electric vehicle is established, and the vibration performance indexes are presented. The frequency response characteristics and statistical characteristics of vibration response quantity are built by the method of frequency domain analysis. The influence of the increased unsprung mass on the vibration performance of electric vehicle is analysed based on B-level road and urban driving condition. The results show that vehicle speed variation has greater impact on the vibration response varibles of in-wheel motor electric vehicle; and the increased unsprung mass of in-wheel motor electric vehicle exerts a little influence on body acceleration and wheel displacement, but has a serious impact on wheel acceleration and an evident influence on relative dynamic load of wheel, as well as a certain influence on suspension deflection.