Robust stabilization of a class of uncertain systems with time delay

In this paper, the problem of stabilizing uncertain systems with time delay by low order controllers is considered. The set of all stabilizing controllers, having three parameters, are determined for this class of time delay systems. First, the D-decomposition method is employed to solve the problem for plants without uncertainty. The approach consists of using two subsidiary quasi-polynomials. Next, the convex direction concept together with Kharitonov plants are used to solve the original problem. Examples are given to illustrate the application of the proposed method.