Abstract: A new torque optimization control method based on predictive control for emergency braking of a four-wheel hub electric vehicle compound braking(hydraulic braking and regenerative braking)system is proposed. The torque optimization controller can quickly track and respond to the optimal slip ratio stable area of the vehicle under different pavement friction conditions. At the same time， an energy recovery trend optimization item is added into the control objective function so as to adjust the vehicle’s energy recovery target quickly and dynamically. By adjusting and optimizing the weight of the objective function， braking safety is achieved and the energy recovery capability of the vehicle is improved as well. A vehicle model was established in Carsim， and a joint simulation platform was built with Simulink. The results show the superiority of the proposed torque optimization method.

Key words: vehicle engineering; predictive control; slip rate; regenerative braking; hydraulic braking