不确定非线性切换系统鲁棒容错H∞控制与仿真

摘要

为了克服外部扰动与执行器失效对切换系统的不良影响,使系统具有可靠性和抗干扰性,针对一类不确定非线性切换系统,研究了鲁棒容错H∞控制器设计与切换问题.假设系统中存在外部扰动,并且所有的矩阵同时带有未知、时变和范数有界的不确定性.当有执行器失效,并使得每个子系统均不能镇定的情况下,利用线性矩阵不等式技术和多李亚普诺夫函数法设计γ次优鲁棒H∞反馈容错控制器和切换策略,保证切换系统能全局二次稳定并且满足日∞性能指标,对得到的γ次优鲁棒H∞容错控制器进行优化,通过变量替换法获得了γ最优鲁棒H∞容错控制器.仿真结果表明,在执行器正常工作和一些执行器发生失效时,容错控制器和切换策略是有效的.%To overcome the passive effect of external disturbance and actuator failures on switched systems,and make systems fault-tolerant and anti-jamming,a design approach of robust fault-tolerant H∞ controller and switched law for uncertain nonlinear systems was investigated.Suppose the systems contain external disturbance and all systems matrices contain unknown and time-varying norm-bounded parameter uncertainties,the purpose of this approach is to designγ-suboptimal robust H∞ feedback fault-tolerant controllers and a switching law,and they can guarantee the systems globally quadratically stability and H∞ performance,when some actuators experience failures such that each subsystem can not be stabilized.Linear matrix inequality (LMI) technique and multiple Laypunov function method were adopted to accomplish the purpose addressed,and the variable substitution was used to acquireγ-optimal robust H∞ feedback fault-tolerant controllers.Finally,simulation results illustrate that the proposed approach is valid not only when all actuators are operational,but also when some actuators faults occur.