T-S fuzzy descriptor systems are used to approximate or represent global nonlinear descriptor systems by using multiple local linear descriptor systems.Sliding mode control can overcome the uncertainty of the systems,and has strong robustness to disturbance and unmodeled dynamics,especially for nonlinear systems.At present,most of the mature and perfect theoretical results of sliding mode control are based on the state feedback information,but the state variables are internal variables,which can not be measured directly,and the information that can be provided to actual T-S fuzzy descriptor systems is often about the output rather than the state information.Therefore,it is important for T-S fuzzy descriptor systems to study how to design the sliding mode controller only based on the output information and guarantee its excellent robust performance under full state feedback as much as possible.Considering several types of uncertain time-delay T-S fuzzy descriptor systems,the problems of output feedback sliding mode control are studied based on sliding mode control theory,Lyapunov method,and LMI(linear matrix inequality)method in this thesis.The main content may be summarized as follows:1.The admissibility analysis and output sliding mode controller design are studied for a class of T-S fuzzy descriptor systems with external disturbances.Firstly,an integral sliding surface is given,which can be designed by output information.Then,by the theory of sliding mode control,Lyapunov function and LMI method,the regularity,the absence of impulse and stability of sliding mode are proved,and a sufficient condition of admissibility is obtained.Finally,the output sliding mode controller is designed to make that the state trajectories can be reached onto the sliding mode surface in a limited time and tended to be stable.The simulation results have been verified by MATLAB.2.The output sliding mode control is studied for a class of uncertain continuous T-S fuzzy descriptor systems with time-delay and external disturbance.Firstly,a new integral type sliding surface is proposed,which has been designed by output information.Under the condition of the hypothesis,sufficient conditions for the admissibility of sliding mode dynamics have been obtained by designing a delay-dependent Lyapunov function.Another sufficient condition for the admissibility of sliding mode dynamics is considered in the case of uncertainties.Finally,an output sliding mode controller is designed.An example illustrates its effectiveness of the conclusion.3.The output sliding mode control is studied for a class of uncertain discrete T-S fuzzy descriptor systems with time-varying delay.Firstly,a new type of output-dependent sliding surface is designed.According to the sliding mode control theory of discrete systems,the quasi sliding mode dynamics equation is obtained.Then,sufficient conditions for the quasi sliding mode to be allowed have been obtained by Lyapunov function and LMI method,and the feedback gain matrices are obtained.Finally,an output sliding mode controller is designed,and the validity of the conclusion is illustrated by an example and Simulink. |