Delay-dependent robust H∞ control of uncertain linear systems with time-varying delays

This paper proposes an optimization-based approach to the robust H∞ control problem of uncertain continuous or discrete-time linear time-invariant systems with different time-varying delays in the state vector and control input of the dynamic equation and controlled output. Sufficient delay-dependent conditions are derived for the control stabilization problem, where both the size of the time-varying delay and the size of its time derivative (in the continuous-time case) play a crucial role for the closed-loop stability with a guaranteed H∞ performance index. The solutions that are proposed for the H∞ control problem are similar or less conservative, when compared to other recent approaches.