执行器有时滞的馈能式主动悬架的鲁棒控制

车辆用的馈能式主动悬架系统具有不确定参数,而且执行器有时滞.为了保证其稳定性、减振性和能量回收性能,我们提出了一种保成本/H∞鲁棒控制器设计方法.对车辆悬架系统性能方面的要求,用二次型加权性能指标和H∞性能指标反映.定义了一个Lyapunov函数代表这两个性能指标;根据这个Lyapunov函数,把闭环系统设计问题转化为一组线性矩阵不等式以求解控制器.根据直流电机工作原理,分析了参数摄动和执行器时滞对系统能量平衡的影响,推导出了能量平衡方程.最后对二自由度1/4车悬架模型进行了仿真;结果表明:对一定范围内的参数摄动和有界时滞,悬架系统在有效减振的同时,实现了能量的回收.

Robust control for self-powered active suspension with time-delay in actuator

For the self-powered active vehicle suspension system with parameter uncertainties and time-delay in the actuator, a guaranteed-cost/H-infinity robust controller is designed to ensure the system performances in stability, vibration isolation and energy feedback. In the controller design, parameter uncertainties and the time-delay in actuator are taken into consideration. The requirements on vehicle suspension systems are described by a quadratic weighted performance index and an H-infinity performance index. Both performance indices are combined into a Lyapunov function which is to be satisfied by the closed-loop system, formulating the design problem into linear matrix inequalities that are solved for the controller. Based on the DC motor principle, the impact of parameter perturbations and time-delay in the actuator on the energy balance is analyzed, and an energy balance equation is developed. Simulation is made on a two degrees-of-freedom quarter-car suspension model with a certain range of parameter perturbations and bounded time-delay. Results show that this suspension system guarantees effective vibration isolation while realizing energy reproduction.