Determination of Whitening Filter Order for Estimation of Electromechanical Mode by Regression Model Representing Power System Damping Characteristics

Abstract

This paper proposes a new method to estimate accurately modal damping of a weakly damped electromechanical oscillation in power systems. The proposed method is based on a whitening filter (FIR filter) to estimate modal damping from system response and a regression model to express the relation between the modal damping and system state variables such as active and reactive power outputs of generators. The feature of the method is that an optimal order of the whitening filter is determined so as to minimize the error of the linear regression model. The simulation study by using the IEEJ EAST 10 machine model shows that the proposed method is effective for accurate estimation of weakly damped oscillation mode.