New condition for improved robust reliable controller design for neutral system with time delay

In this paper, the guaranteed cost control problem for a class of neutral delay-differential systems with a given quadratic cost functions is investigated. The problem is to design a memory state feedback controller such that the closed-loop system is asymptotically stable and the closed-loop cost function value is not more than a specified upper bound. Some criteria for the existence of such controllers is derived based on the linear matrix inequality (LMI) approach combined with the Lyapunov method. A parameterized characterization of the controllers is given in terms of the feasible solutions to the certain LMIs. A numerical example is given to illustrate the proposed method.