BIASED MODEL REDUCTION BY SIMPLIFIED ROUTH-APPROXIMATION AND CONTROLLER DESIGN

Abstract

Model reduction by Simplified Routh Approximation method (SRAM) is presented for both frequency as well as time domain. In the frequency domain this method is extended to produce biased models. The method uses only one Routh-type array to generate both numerator and denominator of the Kth -order model . Computation of the time moments and Markov parameters of the retained, system beforehand and solving the pade equation for the reduced numerator are not necessary. In the time domain (State-space form), it avoids the necessity for matrix inversion and multiplication of the system matrices and the use of recursive formulas. PID controller design is done using Pade-Approximation technique and by Tuning of PID parameters. The performance of reduced order models and controller has been tested by comparing the respective step responses using MATLAB.