OUTPUT DEADBEAT CONTROL THROUGH AN OBSERVER IN NONLINEAR DISCRETE-TIME SYSTEMS

摘要

An observer-based output deadbeat control problem for general mul-tivariable discrete-time nonlinear systems is discussed in this paper. We find that the sufficient conditions for the existence of observer-based deadbeat controllers, which regulate the output of the system from any initial state to zero in a finite time, are that the system is locally uniformly N-observable and the distinguishable subsystem is locally feedback linearizable. The proposed deadbeat controllers can be actually constructed, and the deadbeat time can be exactly calculated. Next, we also find that the closed-loop system is asymptotically stable if the maximal unobservabilizable dynamics is asymptotically stable. Moreover, the time-optimal state deadbeat control problem can also be solved via the proposed observer-based controller. Finally, a design algorithm is introduced, and two examples are given to illustrate our results.