Delay-dependent adaptive robust H∞ control for uncertain linear systems with time-varying delay

This paper considers the problem of delay-dependent adaptive robust H_infin control for uncertain linear systems with time-varying delays. The uncertainties are assumed to be time-varying, unknown, but bounded. A new adaptive robust H_infin controller is presented, whose gains are updating automatically according to the online estimates of uncertain parameters. By combining the idea of indirect adaptive control method and linear matrix inequality method to derive a new adaptive H_infin controller, sufficient conditions with less conservativeness than those of the corresponding controller without adaptive mechanism are given to guarantee both robust asymptotic stability and H_infin disturbance attenuation. An numerical example and its simulation results are given to demonstrate the effectiveness and the benefits of the proposed method.