Delay-dependent robust H∞ control of nonlinear uncertain time-delay systems

Delay-dependent robust H∞ controller design problem for time-delay systems with a class of nonlinear uncertainties is discussed in the paper. Assuming that the nonlinear uncertain functions in the considered model are gain-bounded, we obtain a sufficient condition for the robustly asymptotic stability and H∞ performance of the closed-loop system in the light of Lyapunov stability theory. By solving a linear matrix inequality (LMI), we construct state feedback control law which guarantees the robustly asymptotic stability of the closed-loop system and reduce the effect of the disturbance input on the controlled output to a prescribed level. The delay-bound or the H∞ performance bound can be optimized. A numerical example illustrates the potentiality of our claim.