Reduced-order output feedback controllers for discrete-time systems

摘要

This article considers the stabilization by output feedback controllers for discrete-time systems. The controller can place all of the closed- loop poles within a specified disk D(-α,1/β), centred at (-α, 0) with radius 1/β, where |-α|+1/?<1. The design method involves the decomposition of the system into two portions. The first portion comprises of all of the poles that are lying outside of the specified disk. a reduced-order model is constructed for this portion. The second portion comprises of all of the remaining poles of the system and is characterized by an H_∞-norm bound. The controller design is then accomplished y using H_∞-control theory. It is shown that, subject to the solvability of an algebraic Riccati equation, output feedback controllers can be systematically derived.