On Selecting Low Order Discrete-Time Modes Based on Dominant Energy Modes

Abstract

This brief proposes a simple criterion for selecting low order modes of discrete multivariable systems for model reduction. From the view point of power spectrum of the system output, the dynamic modes with dominant energy contributions instead of those with dominant eigenvalues will be retained. By using this criterion a simple model reduction procedure is developed. One advantage of this reduction technique is that the stability of the original system is preserved.