An alternative delay-dependent H∞ controller design is proposed for linear, continuous, time-invariant systems with unknown state delay. The resulting delay-dependent H∞ control criterion is obtained in terms of Park’s inequality for bounding cross term. The H∞ controller determined by a convex optimization algorithm with linear matrix inequality (LMI) constraints, guarantees the asymptotic stability of the closed-loop systems and reduces the effect of the disturbance input on the controlled output to within a prescribed level. A numerical example illustrates the effectiveness of our method.

Issue Section:
Technical Briefs
Keywords:
optimal control, delay systems, linear systems, continuous time systems, convex programming, linear matrix inequalities, asymptotic stability, closed loop systems, control system synthesis, Time-Delay System, Delay-Dependent Criterion, H∞ Control, Linear Matrix Inequality (LMI)
Topics:
Closed loop systems, Control equipment, Delays, Design, Linear matrix inequalities, Theorems (Mathematics), Stability
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