Observer-based h 8control of uncertain singular systems with time-varying delay

This paper is devoted to the problem of robust H_infin control for a class of uncertain singular systems with time-varying delay and norm-bounded parameter uncertainties.The states of the singular system are unmeasured. A state feedback controller based on an observer is proposed. The observer system is singular and with the same dimension as that of the given singular system. By employing free-weighting matrix and linear matrix inequality (LMI)approach, a new stability criterion for the nominal and unforced singular system is obtained. Based on this criterion, a delay-dependent sufficient condition is given to ensure that there exists an observer-based state feedback stabilizing controller such that the augmented closed-loop system is regular, impulse free and stable with the prescribed H_infin performance level for all admissible parameter uncertainties, and the corresponding design algorithm of observer and controller is proposed.A numerical example is included to show the effectiveness of the proposed method.