中文摘要：

动力转向系统对电动汽车的设计与装配具有重要的影响.动力转向系统具有典型的不确定性、未建模动态、测量噪声和干扰等非线性动力学特征,是包含离散事件与连续事件的混杂动力学系统.分析了分布式驱动电动汽车动力转向系统的控制结构、控制功能及其动力学行为,建立了反映连续和离散控制行为的混杂控制系统模型;建立了动力转向系统的切换控制结构,进行了20 km/h和40 km/h下的蛇形实验.结果表明：在20 km/h下,转向系统转矩的峰值和平均值分别降低了40.93％和40.99％;在40 km/h下,转向系统转矩的峰值和平均值分别降低了31.11％和32.12％,转向轻便性得到明显改善.不仅改善了动力转向系统的鲁棒性能,而且对电动汽车控制性能的改善、性能的优化及安全性能的提高都具有重要的实用价值.

英文摘要：

Power steering system is one of the key parts of distributed electric drive vehicles in their design and assembly.Power steering system is not only a complex nonlinear dynamic system with uncertainty,unmodeled dynamics,measurement noise and interference,but a hybrid system including both discrete event and continuous dynamics also.The structure,control function and dynamic behavior of power steering system were analyzed.The functional model structure and implement model structure reflecting both the discrete and continuous dynamic behavior of hybrid system of power steering system were established.The switched control of hybrid system was established.The pylon course slalom test was executed under 20 km/h and 40 km/h speed condition respectively.The results show that the peak value and standard deviation of steering torque are reduced by 40.93％ and 40.99％ respectively when 20 km/h speed,and by 31.11％ and 32.12％ respectively when 40 km/h speed,the steering portability is improved obviously.The dynamic mechanism and equation has improved the robustness of power steering system.It has practical significance to the overall design of power steering system,the improvement and optimization of system＇ s function and the steering manipulation safety.