Approximation of interconnected power system models using enhanced Schur method for balanced truncation and application to controller design

This paper presents a novel method for reducing the complexity of high-order LTI MIMO systems. Utilising the Schur technique for balanced truncation (SMBT), the approach avoids the need for balancing transformation in obtaining the denominator coefficients of the reduced model. A straightforward mathematical procedure is employed to construct the numerator coefficients, enhancing steady-state approximation and eliminating the need for Routh tables, time moments, and Markov parameters. The reduced model is used to design a controller for the original plant using model-matching concepts in the Pade sense. The performance of the simplified model and controllers is evaluated through numerical examples, with improvements in time response characteristics, ISE, and RMSE over the existing SMBT method.