Reducing conservatism of stability criteria for linear systems with time-varying delay using an improved triple-integral inequality

Abstract

This paper focuses on stability analysis of linear systems with time-varying delay, where two cases of the time-varying delay are discussed, that is, the time-varying delay is either differentiable or just uniformly continuous. First, an improved triple-integral inequality is proposed to estimate triple-integrals tightly. Then, by introducing two novel Lyapunov–Krasovskii functionals catering for two cases of time-varying delay, two sufficient conditions on stability, respectively, for the system under two cases of time-varying delay are derived using the improved triple-integral inequality and a necessary and sufficient condition on quadratic matrix inequalities reported recently. Finally, three numerical examples show that the obtained results outperform some existing ones.