Robust stability bounds for time-delay systems: LMI characterization and computation

This paper is concerned with the computation of robust stability bounds for time-delay systems with nonlinear time-varying perturbations. Firstly, a delay-independent condition on the robust stability is presented and a method to determine the maximum upper bound of robust stability is given. Then, a delay-dependent robust stability condition is provided. All results are given in terms of LMIs where efficient solution procedures are available. Numerical examples have showed that the results are less conservative than some previous established bounds.