ROBUST REJECTION OF PERIODIC AND ALMOST PERIODIC DISTURBANCES

摘要

We present algorithms to exponentially reject periodic and almost peri- odic disturbances, the motivating application being a rejection of reel eccentricity induced disturbances in tape-drive systems. The prevalent periodic disturbance rejection algorithms rely on a constant gain approximation of the system at a particular frequency. These are inadequate for this application because a tape-drive system has parametric uncertainties and because the disturbance is time-varying. We present a robust extension of an existing technique derived by Bodson et al. and further use quadratic and parameter-dependent Lyapunov functions to synthesize gain-scheduled feedback compensators.