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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Fortuna L, Nunnari G, Gallo A (2012) Model order reduction techniques with applications in electrical engineering. Springer, LondonGoogle Scholar
Singh J, Vishwakarma C, Chattterjee K (2016) Biased reduction method by combining improved modified pole clustering and improved Pade approximations. Appl Math Model 40(2):1418–1426MathSciNetCrossRefGoogle Scholar
Prajapati AK, Prasad R (2019) Reduced-order modelling of LTI systems by using Routh approximation and factor division methods. Circuits Syst Signal Process 38:3340–3355CrossRefGoogle Scholar
Sastry G, Krishnamurthy V (1987) Biased model reduction by simplified Routh approximation method. Electron Lett 23(20):1045–1047CrossRefGoogle Scholar
Chen T, Chang C, Han K (1980) Stable reduced-order Padé approximants using stability-equation method. Electron Lett 16(9):345–346CrossRefGoogle Scholar
Panda S et al (2009) Reduction of linear time-invariant systems using Routh-approximation and PSO. Int J Appl Math Comput Sci 5(2):82–89Google Scholar
Bandyopadhyay B, Ismail O, Gorez R (1994) Routh-Pade approximation for interval systems. IEEE Trans Autom Control 39(12):2454–2456MathSciNetCrossRefGoogle Scholar