Robust output regulation and tracking for linear periodic systems under structured uncertainties

The problem of robust output regulation and tracking is studied for a linear periodic discrete-time system whose state-space description depends on some unknown parameters. The preservation of asymptotic regulation and tracking under perturbations of such parameters is obtained for classes of exponential disturbance functions and reference signals. Both the conditions for the existence of a solution and a constructive design procedure for the periodic compensator are given. Copyright © 1996 Elsevier Science Ltd