MODEL REDUCTION OF CONTINUOUS AND DISCRETE TIME SYSTEMS USING MODIFIED CAUER FORM

Abstract

In this dissertation the model order reduction problem for continuous and discrete time systems has been carried out using Modified Cauer Form (MCF)- of Continued Fraction Expansion (CFE). The model reduction problem has been tried using three different methods for continuous time systems (1) Modified Cauer Form of Continued Fraction Expansion (2) mixed method using Routh Stability Criterion And Modified Cauer Form and (3) mixed method using Stability Equation method and Modified Cauer Form. The above _methods have also been extended for discrete time systems using the advantages of (1) Linear Transformation and (2) Bilinear Transformation. Beside. it a PID controller has also been designed for the original plant and by taking reduced order models of plant. The performance comparisons of original and reduced order systems has been carried out by comparing the step responses of original system and reduced order models. The suitability of reduction methods have also been tested by designing a PID controller and also by comparison of the dynamic characteristics such as maximum overshoot, rise time, peak time , settling time etc.