Fault Estimation and Fault-Tolerant Control for a Class of Continuous-Time PWA Systems: A Region-Dependent Intermediate Variable Observer Approach

In this paper, the design issues of both the fault estimation (FE) and fault-tolerant control (FTC) are investigated for a class of piecewise-affine (PWA) systems against actuator fault. Firstly, a novel region-dependent intermediate variable observer is designed to estimate the system states and the actuator fault simultaneously. Secondly, based on the above estimated information, a class of output-feedback-based PWA FTC strategies is proposed. Furthermore, by using two region-dependent Lyapunov functions and the S-procedure with an ellipsoidal outer approximation estimation method, sufficient conditions are obtained such that the estimation error system is uniformly asymptotically bounded and the closed-loop system is asymptotically stable with a guaranteed
$H_{\infty}$
performance index, respectively. Finally, the effectiveness of proposed methods is demonstrated via an illustrative example.