Citation :

Nagalla Sowjanya, D. Vijaya Kumar, P. MallikarjunaRao, "Model Order Reduction of Interval Systems in Z-Domain Using the Improvement of Simplified RAM," International Journal of Electrical and Electronics Engineering, vol. 13, no. 4, pp. 133-139, 2026. Crossref, https://doi.org/10.14445/23488379/IJEEE-V13I4P110

Abstract

This study emphasizes an improvement method for Simplified Routh Approximation with discrete-time SISO interval systems. The diminished order model's numerator and denominator are estimated using the θ interval table. The Kharitonov polynomial is also used to verify the proposed inferred interval model's stability. The enhanced approach sustains the reduced system's stability feature if the system of high-rise order intervals is sturdy. The limitation of calculating the reciprocal transformation and inverse reciprocal transformation, observed in the very recent Advanced Routh Approximation Method, has also been avoided in the suggested procedure. To substantiate the relevance of the initiated approach, plotting of impulse and step responses for the reduced models as well as the system. A mathematical example is comprehended to elucidate the proposed method and simplified to the Simplified Routh Method, Model order in discrete time order, uncertain method, and mixed method (α and β method) of integral square error values. To obtain the results, interpret the efficacy and accuracy of this intended approach.

Keywords

Interval Analysis, Discrete Systems, Improvement of Simplified Routh Approximation Method, Kharitonov Polynomials, Model Order Diminish, Integral Square Error.

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