Robust fault estimation based on learning observer for Takagi-Sugeno fuzzy systems with interval time-varying delay

摘要

This paper studies the problem of robust fault estimation for a class of Takagi-Sugeno(T-S) fuzzy systems which subject to interval time-varying delay, external disturbance, and actuator fault. The designed learning observer can achieve simultaneous estimation of system state and time-varying or constant actuator fault. Then, we construct a new Lyapunov-Krasovskii functional including the information of the lower and upper delay bounds; compared with the time-varying delay, the interval time-varying delay is the less conservative form. Furthermore, one less conservative delay-dependent condition for the existence of learning observer is given in terms of linear matrix inequalities. In addition, the results for the systems with interval time-varying delay are simplified when the delay is not concluded. Finally, simulation results of two examples are presented to show the effectiveness of the proposed method.