Active fault tolerant control for a class of linear time-delay systems in finite frequency domain

Abstract

This article deals with the problem of active fault tolerant control (AFTC) for a class of linear time-delay systems in a finite frequency domain. A new ℋ_∞ controller in generalised internal model control architecture with an observer-based fault estimator is proposed for the AFTC system. Based on online fault estimation and accommodation, the closed-loop system stability and ℋ_∞ performance for both fault free and faulty cases are guaranteed. With the aid of the generalised Kalman–Yakubovich–Popov lemma for time-delay systems, sufficient conditions on the existence of such an AFTC system ensuring simultaneous finite frequency estimation and control performance are derived. The calculation procedure of the parameter matrices of the fault estimator and ℋ_∞ controller is also proposed. Finally, a numerical example is given to illustrate the effectiveness of the proposed method.

Keywords:

• active fault tolerant control
• linear time-delay system
• generalised Kalman–Yakubovich–Popov lemma
• finite frequency
• generalised internal model control

Acknowledgements

The work was supported in part by NSFC (60774071), the National 863 Program (2008AA121302), the 973 Programme (2009CB724000), and the State Scholarship Fund of China.