A New Biased Model Order Reduction for Higher Order Interval Systems

Mangipudi Siva Kumar,Gulshad Begum

doi:10.15598/aeee.v14i2.1395

Abstract

This paper presents a new biased method for order reduction of linear continuous time interval systems. This method is based on the Stability equation method, Pade approximation and Kharitonov’s theorem. The higher order interval system is represented by four Kharitonov transfer functions using the Kharitonov’s theorem, and then reduced order models are obtained by the general form of the Stability equation method and Pade approximation. The Stability equation method is used to obtain a reduced order denominator polynomial while the Pade approximation is used for reduced order numerator coefficients. This method generates a stable reduced order model if the original higher order interval system is stable. The proposed method is illustrated with the help of typical numerical examples considered from the literature, and these are compared with well-known methods to show the efficacy of the proposed method.

Highlights

In recent decades, to carry out effective research much effort has been made in the field of model order reduction
Frequency domain order reduction methods are for a transfer function model
The reduced model of denominator polynomial is obtained by using the stability equation method and the numerator is determined by the Pade approximation

Summary

Introduction

To carry out effective research much effort has been made in the field of model order reduction. Some of the most popularly used frequency domain order reduction methods are Pade approximation and continued fraction methods These are computationally fast and being able to exactly match the maximum number of system parameters (usually time moments or Markov parameters) to the reduced model. The advantage of this method is that it preserves stability in the reduced model, if the original high-order system is stable, and retains the first two time–moments of the system These methods are applicable for fixed coefficients systems only. In [15] recently a reduction technique for linear interval systems using Kharitonov’s theorem interval and Routh-Approximation is presented to generate a stable reduced order interval system. Model order reduction of interval systems is carried out by using the Kharitonov’s theorem, stability equation method and Pade approximation method.

Proposed Method

Problem Formulation

A10 0 i

Numerical Example

Conclusion