独立驱动电动汽车横摆力矩的模糊控制算法

A Fuzzy Control System for the Direct Yaw Moment of4WD Electric Vehicles

利用驱动力矩独立可控的优点,设计了四轮独立驱动电动汽车直接横摆力矩的模糊控制系统,以提高整车的操纵稳定性。控制器的上层联合反馈横摆角速度和质心侧偏角两个控制变量的偏差,进行模糊PI控制计算出整车所需总的横摆力矩;控制器的下层根据各轮对横摆力矩的贡献、各轮驱动极限和附着极限制定模糊规则,将所需横摆力矩有效地分配到各轮。同时,应用主流的V模式开发方法实现控制算法的快速开发和验证:运用自动代码生成工具,分别将控制算法和整车模型下载到实际控制器和AD5435仿真机,进行硬件在环仿真。不同工况下的仿真结果分析表明:控制系统能够有效地改善车辆的操纵稳定性,控制算法具有可行性和高效性。

A fuzzy control system for the direct yaw moment of four-wheel drive electric vehicles is proposed to improve vehicle＇s steering stability.The upper layer of the controller is a fuzzy PI controller,and uses the deviation between actual value and reference of side slip angle and yaw rate to calculate the desired yaw moment.The lower layer of the controller effectively distributes the required yaw moment to each wheel following fuzzy logic rules based on the contribution of each wheel to the yaw moment and the driving limit of the vehicle.Moreover,the control algorithm is rapidly developed and verified in V mode：a vehicle model with the proposed control system is established and downloaded into the AD5435simulator to conduct a hardware-in-theloop test.Simulation results show that the proposed control system can effectively improve vehicle＇s handling and stability in different situations,and that the control algorithm is feasible and effective.