Dynamical compensation for time-delay systems: an LMI approach

This paper presents simple and explicit formulae of an 'observer-based H-in finity controller' for linear time-delay systems. Based on the LMI approach , we design a dynamical controller which guarantees the asymptotic stabilit y of the closed-loop system and reduces the effect of the perturbation to a prescribed level. The main contribution of the paper is to provide closed- loop stability analysis when the system time delay is unknown. We give dela y-dependent and delay-independent stability results. The proposed method is illustrated by examples. The paper completes the work of the same authors. Copyright (C) 2000 John Wiley & Sons, Ltd.