Order Reduction using Basic Characteristics and Factor Division Method

Abstract

The authors propose a mixed method for reducing the order of the high order dynamic systems. In this method, the denominator polynomial of the reduced order model is obtained by using the basic characteristics of the higher order system which are maintained in the reduced model while the coefficients of the numerator are obtained by using factor division method. This method is fundamentally simple and generates stable reduced models if the original high-order system is stable. The proposed method is illustrated with the help of the numerical example taken from the literature.

Introduction

Conclusion

The authors presented an order reduction method for the linear dynamic system of high order systems. The basic characteristics of original system are utilized for determination of denominator polynomial of the reduced model while Factor division algorithm is used for calculation of the numerator coefficients. The advantages of proposed method are stable, simplicity, efficient and computer oriented. The proposed method has been explained with an example taken from the literature. The step responses and Bode plots of the original and reduced system of second order are shown in the Figure-1 and Figure-2 respectively. A quantitative comparison of reduced order model obtain by proposed method with the original system is shown in the Table-I from which we can conclude that proposed method is comparable in quality.

References

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Copyright

Copyright © 2023 Naaz ., Jasvir Singh Rana. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.