线控双电机转向系统滑模同步控制及其硬件在环仿真

To meet the high safety standards of high-grade automatic-driving steering actuators, a steering-by-wire system with redundant dual-motor steering actuators was studied. To address the problem of unsynchronized dual-motor steering servo control, a synchronous control strategy based on sliding mode control was proposed. First, the structural principles of a steering-by-wire system with redundant dual-motor steering actuators were analyzed, and a steering actuator model of a steering-by-wire system and a two-degree-of-freedom vehicle model were established. Then, to realize the angle servo control of the steering actuators, a speed synchronization controller was designed based on closed-loop control strategies for position, speed, and current. To handle speed unsynchronization in the operation of the two steering motors, a sliding mode control method was adopted. The speed difference between the motors was used as the input of the controller, and the compensation amount for the current of the dual motor was obtained, which was superimposed on the target current. Moreover, by comparing the proposed control strategy with traditional PID control, it was verified that the wire-controlled dual-motor actuator based on sliding mode synchronous control can better coordinate the speed of the dual motor and realize synchronous operation. Finally, a hardware-in-loop test bench for a steering-by-wire system was constructed to verify the effectiveness of the proposed control strategy. The results demonstrate that the sliding mode synchronous control strategy of the dual-motor steering-by-wire system can realize angle servo control, reduce the speed synchronism of the dual-motor, and ensure synchronous operation of the angle servo of the steering-by-wire system.