On the vehicle stability control for electric vehicle based on control allocation

This paper proposes a vehicle stability control (VSC) scheme for a four-wheel-drive electric vehicle based on the control allocation techniques. The wheels of the electric vehicle are driven by the electric motor individually, which makes it more convenient to control tires forces and moments for stabilizing vehicle motion. But the over-actuated system is complex to control. The control allocation technique is well-known used in marine craft and aircraft to resolve over-actuated problems. By introduction of control allocation to electric vehicle control, a large degree of modularization of the different levels of control is obtained. A control analysis layer is designed using a sliding mode control, which specifies a desired yaw moment to satisfy the vehicle stability. And then the control allocation distributes this yaw moment among the individual wheels by commanding appropriate wheel longitudinal slip. Simulation results in the Carmaker^reg environment have shown that the proposed control scheme takes advantages of electric vehicle and enhances the vehicle stability.