增强电动助力转向系统抗干扰性能的混合H_2/H_∞控制

根据纯电动大客车电动助力转向(EPS)系统工作的具体要求,开发了适合电动大客车EPS系统使用的循环球式转向器,并建立了其动力学模型。针对EPS系统存在模型、干扰、噪声等不确定性,以及对系统鲁棒性和动态特性的要求,运用加权指标方法设计和优化了混合H2/H∞控制器,并进行了仿真分析。结果表明:基于混合H2/H∞控制的EPS系统可有效抑制路面随机激励、转矩传感器噪声以及减少转向盘振动,使驾驶员获得较满意的路感。台架试验表明:提出的控制方法是有效可行的,设计的EPS系统可有效改善大客车的操纵稳定性。

Mixed H_2/H_∞ control for enhancing anti-interference performance of EPS system

According to the requirements of the electric bus on the electric power steering(EPS), a recirculating ball type EPS system was designed and its dynamic model was established. Because of the existence of system uncertainties in modeling, signal disturbance, sensor noise, considering the requirements on the system robustness and the dynamic performance, a mixed H_2/H_∞ controller was designed and optimized by the mixed weighted index optimization. The simulation results showed that this optimal control method could attenuate the random road excitation, torque sensor measurement noises and disturbances, reduce oscillations that might occur in the steering column,provide satisfied road feeling for drivers. The simulation results were verified by the bench test. The test results showed that the mixed H_2/H_∞ controller for the recirculating balltype EPS system is feasible and effective, and it improves the vehicle steering and handling stability.