Robust Control Of A Class Of Switched Systems

In the field of modern control,simple linear systems or nonlinear systems are no longer sufficient for engineering needs.In practical systems,it is difficult to describe with a continuous time system or a discrete system,so it is necessary to find a suitable model to represent these complex systems.It is difficult to describe the system accurately,because there are always some perturbations of model parameters or disturbances of external environment,so the accurate model cannot be obtained.At the same time,due to physical constraints,the system will always shows some non-linear phenomena,such as input saturation.The switched systems consist of continuous subsystems and discrete switching rules,and is the most important class of complex systems.According to the special structure of the switched systems and the related problems that may exist in the switched systems,the main results of this paper are summarized as follows:Firstly,the robust control problem for a class of uncertain input-saturation linear systems is considered.The model of the linear system contains model parameter uncertainties,and the system also has external disturbances.UDE-based robust control methods are used to give appropriate filters to estimate the uncertainty and disturbance,and a robust stabilization controller is obtained to stabilize the system.Next,the robust control problem for uncertain linear switched systems is studied.For the linear switched systems with model parameter uncertainty and external disturbance,the common Lyapunov function method is combined with the UDE-based robust control method.The stability conditions of the system under arbitrary switched signals are given,and a robust controller is designed to stabilize the system.By combining the mean dwell time method with UDE-based robust control method,the conditions for the stability of the system under given switching signals are given,and a robust controller for stabilizing the system is designed.Then,the robust control problem of a special Hamilton nonlinear switched system is studied.The UDE-based control method is combined with the state feedback method to design a robust controller to make the nonlinear switched systems globally asymptotically stable.Finally,the work of this paper is summarized and the future research work is prospected.