Several Networked Systems With Time Delay Control Problem

This paper is concerned Networked control systems(NSCs) with the communica-tion limitations including signal transmission delay and packet-loss. First of all, anuncertain discrete-time system model of NSCs is established. Then, stability and ro-bust stabilization problems for NSCs with time-delay, and the problem of designinga robust state-feedback guaranteed cost controller are studied, respectively.Firstly, consider the stability problem of NSCs with time-delay. A new model ofnetwork control systems is frstly established with two additive delay components,where one is known constant, and the other is unknown. By constructing a newLyapunov functional and using the so-called delay-partitioning method combinedwith Jensen inequality technique, a new sufcient criterion for stability of NCSs isproposed in terms of linear matrix inequality, and it is shown to be less conservative.Secondly, based on the obtained stability criterion, a network controller forNCSs such that the resultant closed-loop systems is robustly stable is designed.Furthermore, by comparing with our approach and one in literature, we fnd thatthe approach proposed in this paper is less conservative.Thirdly, the guaranteed cost control problem of NCSs is studied. We designa robust guaranteed cost controller for NCSs, such that the resultant closed-loopsystems is robustly stable, and a specifed quadratic cost function is bounded forall admissible uncertainties. A gain matrix of the robust state-feedback guaranteedcost controller can be obtained by determining feasible solutions of linear matrixinequalities.The efectiveness of these methods proposed in this thesis are demonstrated bynumerical examples.