l(1) robust performance of discrete-time systems with structured uncertainty

摘要

This paper addresses the robust performance problem when a linear time-invariant system is subjected to both norm bounded time-varying uncertainty and worst-case external bounded input. The tightest upper bounds for steady-state robust performance measures over classes of finite memory and fading memory perturbations are computed in the regulation and tracking problems. Since the classes of finite memory and fading memory perturbations are inappropriate to the purposes of model validation and adaptive control, approximating subclasses of bounded memory perturbations and perturbations with exponentially decreasing impulse responses are considered. It is shown that the robust performance bounds obtained are nonconservative in the case of bounded memory perturbations. The worst-case steady-state robust performance measures for SISO system under coprime factor perturbations are computed for illustration. (C) 2001 Elsevier Science B.V. All rights reserved. [References: 10]