Robust fault estimation based on Proportional Integral observer for Takagi-Sugeno fuzzy systems with actuator and sensor faults

This paper addresses the problems of states and faults estimation for a class of Takagi-Sugeno (T-S) fuzzy systems subject to simultaneously sensor faults, actuator faults and output disturbances. A Proportional Integral (PI) observer is proposed in this paper. The observer can not only estimate system states, sensor faults and actuator faults, but also attenuate the influence of output disturbances by introducing the H
_∞
performance index. In order to get the gain matrices of the observer, one sufficient conditions are deduced in form of Linear Matrix Inequality (LMI) using Lyapunov theory. A numerical example is proposed to verify the effectiveness of the proposed method.