Abstract: Rigid connection of inwheel motor and wheel may increase the unsprung mass of electric vehicle and deteriorate the ride comfort of vehicle. To overcome the negative effects of vertical vibration of wheel, a nonlinear optimal sliding mode fuzzy control scheme is proposed for the inwheel active vibration damper in electric wheel. A quarter vehicle dynamics model is established with consideration of the generalized nonlinear characteristics of suspension, the control of inwheel active vibration damper is fulfilled by linearizing the nonlinear system, constructing an optimal sliding mode fuzzy controller, and delinearization. A comparative simulation is then conducted and the results show that the inwheel active vibration damper in electric wheel with nonlinear optimal sliding mode fuzzy control can effectively reduce the negative effects of vertical vibration of inwheel motor and ensure a better comprehensive ride comfort performance of electric vehicle.

Key words: electric vehicle, inwheel motor, active vibration damper, nonlinearity, optimal sliding mode fuzzy control