New results on delay-dependent control of time-delay systems

This note presents new results pertaining to the delay-dependent stability and control design of a class of linear time-delay systems. A new state transformation is introduced to exhibit the delay-dependent dynamics. For stability, we construct an appropriate Lyapunov functional to derive delay-dependent linear matrix inequality-based sufficient condition. For the feedback control design, we establish schemes based on quadratic H/sub 2/ performance, H/sub /spl infin//, criteria and simultaneous H/sub 2//H/sub /spl infin// synthesis. Under the developed transformation, both the instantaneous and delayed feedback control yield identical results. Numerical examples are presented to illustrate the analytical development.