A class of adaptive controllers with application to robust adaptive control

Abstract

This paper deals with discrete time, single-input single-output systems. A parametrization of a general class of adaptive controllers is given. Using this paramtrization it is shown that an adaptive controller based on the l1 optimal design strategy leads to a globally convergent adaptive scheme. The use of adaptive l1 controllers is motivated by the problem of robust adaptive control, and the results of this paper offer an alternative way of handling this problem.