Time-domain simplification of linear time-invariant systems using Cauer continued-fraction expansion about s=a and s=0 alternately

Abstract

A simple time-domain procedure is presented for deriving simplified models for linear time-invariant systems. It is based on deriving a new realization form for the Cauer continued fraction expansion about s  a and s  0 alternately. A new similarity transformation is also developed which can be used to construct approximate aggregation matrices for the reduced order models obtained by the proposed procedure. Particularly when the original state-space model is in a phase-variable canonical form, the similarity matrix is given explicitly.