Control allocation of vehicle dynamics control for a 4 in-wheel-motored EV

This paper presents a new control allocation scheme for the stability control of a 4WD EV. A hierarchical vehicle stability control strategy is used. The high level of the control strategy is the vehicle motion control level. And the low level is the control allocation level in which the longitudinal force´s distribution is the focal point. Through the analysis of the tire characteristics under the combined longitudinal and lateral forces, an effectiveness matrix for the control allocation considering the longitudinal force´s impact on the lateral force was proposed. Then based on Quadratic Programming method the longitudinal force of each wheel has been optimal distributed. The simulation results indicate that the proposed method can enhance the vehicle handling stability, meanwhile the control efficiency is also improved.