Model reduction of discrete interval system using dominant poles retention and direct series expansion method

This paper presents a method for reduction of discrete interval system using Padé approximation. For a given high-order system, denominator of the reduced model is obtained by retaining dominant poles of the original system and the numerator is obtained by matching first r time moments of the system and its model. The time moments are calculated using novel method i.e. direct series expansion method. Numerical example is given to illustrate the procedure.