Approaches to diminish large unsprung mass negative effects of wheel side drive electric vehicles

Ride comfort and road holding ability of distributed drive electric vehicles are worsened due to large unsprung mass introduced by wheel side drive system. To diminish this large unsprung mass negative effects, three approaches ("Suspension and Reducer Integrated" Close-to-Wheel Drive System, "Dynamic Vibration Absorber" Close-to-Wheel Drive System and in-wheel drive system with "Active and Energy Regenerative Suspension") are introduced. The corresponding dynamics are analyzed and the schemes are provided. Evaluations of suspension performance show the superiorities of these approaches in different magnitude compared with the conventional configuration which is equipped with hub motor and passive suspension. Overall comparisons between three approaches are carried out and the feasibilities are discussed. With proper design according to specific application, these approaches are promising to be applied on various wheel side drive systems.