四轮独立驱动电动汽车路径跟踪鲁棒控制

Robust Control of Path Tracking for Four-Wheel Independent Drive Electric Vehicles

针对四轮独立驱动电动汽车具有结构参数、外部干扰不确定性与非线性和过驱动等特征,提出了一种分层控制框架,以实现前轮转向与直接横摆力矩控制系统协同的车辆路径跟踪控制。首先,基于路径跟踪运动学模型,将车辆的路径跟踪问题转化为约束跟随问题;其次,设计了基于约束跟随的自适应鲁棒上层控制算法,该方法可以有效处理由模型不确定性和外部干扰引起的失配问题,并保证闭环系统的一致有界性和一致最终有界性;最后,设计了一种基于二次规划的下层分配算法满足所需的直接横摆力矩,并在Simulink-Carsim平台进行联合仿真。通过不同工况的仿真结果表明,所设计的自适应鲁棒控制算法具有良好的路径跟踪精度和鲁棒性。

For the characteristics of four-wheel independent drive electric vehicles,such as structural parameters,external disturbance uncertainty,nonlinearity,and over-drive,a hierarchical control framework is proposed to realize the vehicle path tracking control with the coordination of front wheel steering and direct yaw torque control system.Firstly,based on the path tracking kinematics model,the vehicle path tracking problem is transformed into a constrained following problem.Secondly,an adaptive robust upper-layer control algorithm based on constrained following is designed,which can effectively deal with the mismatch problem caused by model uncertainty and external disturbances,and guarantee the consistent boundedness and consistent ultimate boundedness of the closed-loop system.Finally,a quadratic programming-based lower-level allocation algorithm is designed to satisfy the required direct yaw moment.Co-simulation is conducted on the Simulink-Carsim platform.The simulation results of different working conditions show that the designed adaptive robust control algorithm has good path tracking accuracy and robustness.