Inverse Model based Torque Vectoring Control For a Rear Wheel Driven Battery Electric Vehicle

Abstract

This paper presents the torque vectoring control concept for a vehicle with two powerful wheel individual electric drives at the rear axle. The direct yaw moment control which is enabled by a differential torque at the rear axle drives offers the potential for shaping the yaw motion of the car in a considerable range. The control concept introduced here is primarily oriented at practical considerations. Together with the tools presented it is conveniently adaptable to any vehicle data. The focus is on yaw dynamics control. A reference yaw rate is determined by combining conveniently tunable linear dynamics with a nonlinear steady state gain, the latter in order to establish a desired self-steering behavior. An inverse single track model is used for cancellation of the yaw dynamics induced by the yaw torque. It is a significant part of the applied feed-forward control. Moreover, it is employed by the optional yaw rate feedback control which is based on the inverse disturbance observer scheme. Both the effectiveness of the control concept and the practical ease of control parameter calibration were validated in driving experiments.