执行器饱和网络化控制系统鲁棒容错控制研究

Research on Robust Fault-Tolerant Control for Networked Control System with Actuator Saturation

针对实际网络化控制系统(NCS)中存在的执行器饱和约束,及冗余执行器分担故障执行器任务时更易进入饱和区域现象,研究了执行器饱和闭环故障不确定NCS的鲁棒H∞保性能容错控制问题。根据Lyapunov稳定性理论,通过引入辅助反馈矩阵,将执行器饱和项转换成线性函数的凸组合形式,并应用改进的Jensen积分不等式及更紧界引理,推证出执行器饱和闭环故障NCS具有鲁棒H∞保性能容错能力的少保守性时滞依赖充分条件,并给出了鲁棒H∞保性能容错控制器的设计方法及保性能指标、扰动抑制率指标的优化设计。仿真结果表明,所述方法可使同时受到执行器饱和约束、网络属性、模型参数摄动以及有限能量外部扰动影响的闭环故障NCS渐近稳定,且具有一定的抗扰动能力及保代价动态性能。

Because there is the actuator saturation in the networked control system （NCS） and the redundant actuator is easy to enter the saturation region when redundant actuator shares the task of the fault actuator, the problem of the robust H∞ guaranteed cost fault - tolerant control is studied for a class of closed - loop fault NCS with actuator saturation. The actuator saturation item can be expressed as a convex combination of the linear function by introducing the auxiliary feedback matrix. And based on Lyapunov stability theory, the delay - dependent and less conservative sufficient condition that guarantee robust H∞ guaranteed cost fault - tolerant performance of closed - loop fault NCS with actuator saturation is derived by utilizing the improved Jensen inequality and tighter bound lemma. The design method of robust H∞ guaranteed cost faulttolerant controller is given, meanwhile, the guaranteed cost index and the disturbance attenuation index are optimized. The simulation results show that the proposed design method can guarantee stability, and has disturbance resisting and guaranteed cost ability for closed - loop fault NCS, which is subjected to actuator saturation, network attributes, model parameter perturbation and norm - bounded external dis- turbance, simultaneously.