Output feedback adaptive command following and disturbance rejection for nonminimum phase uncertain dynamical systems

摘要

In this paper, we develop an output feedback adaptive control framework for continuous-time nonminimum phase multivariable systems for output stabilization, command following, and disturbance rejection. The approach is based on a nonminimal state space realization that generates an expanded set of states using the filtered inputs and filtered outputs and their derivatives of the original system. Specifically, a direct adaptive controller for the nonminimal state space model is constructed using the expanded states of the nonminimal realization and is shown to be effective for multi-input, multi-output nonminimum phase systems with unstable dynamics. The adaptive controller does not require any model information nor does it require information of the system poles and system zeros or estimation of the system Markov parameters. Several illustrative numerical examples are provided to demonstrate the efficacy of the proposed approach. Copyright © 2010 John Wiley & Sons, Ltd. Received 14 January 2010; Revised 19 April 2010; Accepted 29 June 2010 【keyworks】 output feedback; direct adaptive control; nonminimum phase systems; nonminimal statespace realization; command following; disturbance rejection