Observer-based fault detection for continuous–discrete systems in T-S fuzzy model

Abstract

The observer design problem for fault detection is considered for nonlinear continuous–discrete systems with Takagi–Sugeno fuzzy scheme and finite frequency specification in this paper. Two finite frequency performance indices H− and H∞ are introduced to evaluate the sensitivity to faults and the robustness against disturbances in finite frequency domains. Based on the H−/H∞ technique, this research is aimed to design a fault detection observer for the addressed system. Sufficient conditions are derived to guarantee the asymptotic stability, fault sensitivity and disturbance robustness of the residual error system. Simulation results further demonstrate effectiveness of the proposed approach.