低附着系数路面ESP与EPS协调控制研究

Research on Coordination Control of ESP and EPS on Low Adhesion Road

针对低附路面车辆转向行驶时,由ESP系统工作引起的轮胎自回正力矩严重缺失,设计基于EPS回正力矩补偿控制下的ESP与EPS协调控制策略。当车辆在低附路面出现过度转向时,由EPS回正力矩补偿控制器对轮胎自回正力矩进行补偿,避免驾驶员因路感的缺失而过度反向转动方向盘,并输出控制后的方向盘转角。对由线性两自由度车辆模型求得的理想横摆角速度进行修正,修正值输入给ESP,提高ESP控制精度,保证车辆在低附系数路面转向行驶的操纵性和稳定性。

For the problem of serious loss of self-aligning torque caused by the work of ESP system when the vehicle turns on low adhesion road, coordinated control strategy of ESP and EPS is designed based on compensation of self-aligning torque of the EPS system. When the vehicle is excessively steering on low adhesion road, the EPS aligning torque compensation controller can compensate the self-aligning torque of tires, which can avoid reverse excessive steering by the driver because of the loss of road feel, and can output the steering wheel angle to correct ideal yaw velocity obtained from the linear two degrees of freedom vehicle model. The correction value is input to ESP, which can improve the control precision of ESP, and ensure the handling and stability when vehicle steers on low adhesion road.