Low-order Controller Design Using Coprime Factors and Linear Matrix Inequalities for Discrete SISO Systems

Jaw-Kuen  Shiau; Tsung-Li  Chuang

doi:10.6180/jase.2004.7.1.05

Low-order Controller Design Using Coprime Factors and Linear Matrix Inequalities for Discrete SISO Systems

Aerospace Engineering

Jaw-Kuen Shiau ¹ and Tsung-Li Chuang¹

¹Department of Aerospace Engineering Tamkang University Tamsui, Taiwan 251, R.O.C.

Received: July 2, 2003
Accepted: December 11, 2003
Publication Date: March 1, 2004

Download Citation: ||https://doi.org/10.6180/jase.2004.7.1.05

ABSTRACT

This paper develops a low-order controller design method for linear discrete time-invariant single-input, single-output systems. Using the coprime factors and the properties of discrete outer functions, the low-order controller design becomes a zero-placement problem which is convex. The solutions are obtained using the linear matrix inequality techniques. The proposed design method is used to solve for several optimal control problems, such as pole-placement design, model-matching design, and H∞ optimization problems.

Keywords: Coprime Factorization, Discrete Outer Functions, Linear Matrix Inequalities, Low-order Controller Design, Robust Control Design

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