Reduction of Discrete Interval System Using Mixed Approach

  • V. Singh
  • A. P. Padhy
  • V. P. Singh
Conference paper
Part of the Algorithms for Intelligent Systems book series (AIS)


This article focuses on a new mixed method for finding a reduced order model (ROM) of single-input-single-output (SISO) discrete interval systems (DIS) using direct truncation method and matching of time moments (TM) of higher-order interval systems and ROM. In this method, the DIS is converted to an equivalent continuous interval system (CIS) by simple linear transformation. The denominator of the equivalent continuous interval model is determined using direct truncation method by neglecting higher-order terms of original CIS, and the coefficients of numerator polynomials are obtained by matching the TM. Finally, the obtained reduced order continuous interval model is reconverted into discrete interval model by using inverse linear transformation. The methodology of the proposed technique is depicted for a two-tank plant test system. The responses of system and model validate the effectiveness of the proposed technique.


Model order reduction Discrete interval system Time moments Direct truncation Reduced order model (ROM) 


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Copyright information

© Springer Nature Singapore Pte Ltd. 2020

Authors and Affiliations

  • V. Singh
    • 1
  • A. P. Padhy
    • 1
  • V. P. Singh
    • 2
  1. 1.Department of Electrical EngineeringNITRaipurIndia
  2. 2.Department of Electrical EngineeringMNITJaipurIndia

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