Active fault-tolerant control for switched systems with time delay

This paper focuses on the problem of active fault-tolerant control for switched systems with time delay. By utilizing the fault diagnosis observer, an adaptive fault estimate algorithm is proposed, which can estimate the fault signal fast and exactly. Meanwhile, a delay-dependent criterion is obtained with the purpose of reducing the conservatism of the adaptive observer design. Based on the fault estimation information, an observer-based fault-tolerant controller is designed to guarantee the stability of the closed-loop system. In terms of linear matrix inequality, sufficient conditions are derived for the existence of the adaptive observer and fault-tolerant controller. Finally, a numerical example is included to illustrate the efficiency of the proposed approach. Copyright (C) 2011 John Wiley & Sons, Ltd.