Robust H∞ control of time-delay systems with polytopic uncertainty

In this paper, an improved H_infin performance criterion is derived for a class of time-delay systems. It partially rules out the technical restriction of using a single Lyapunov function, and therefore, is less conservative when used in robust performance analysis and synthesis problems. Based on the criterion, robust H_infin state-feedback controller is designed. Furthermore, multichannel H_infin dynamic output-feedback control problem is also considered. A numerical example is included to illustrate the obtained results.