Model Order Reduction of a Single Area Power System Using Direct Truncation with Mihailov Criteria Technique

In this paper, a single-area power system (SAPS) model is reduced to lower-order (LO) model. A mixed model order reduction (MOR) method is applied to obtain reduced order model (ROM). Direct truncation (DT) approach is applied for order reduction of numerator polynomial, where as, Mihailov criteria technique adopted to obtain reduced order denominator polynomial. The eleventh-order SAPS is taken into account as a numerical example to obtain second-order model. The validity of ROM is tested by plotting time and frequency responses, and comparing the time domain specifications. Also error indices including integral square error (ISE), integral absolute error (IAE), integral time absolute error (ITAE), and integral time squared error (ITSE) are utilized for performance comparison of the proposed model.