Improving Step Performance of PMU Algorithms: Left and Right Taylor-Fourier Expansions

Modern power systems are characterized by fast dynamics, due to the massive presence of power electronic converters. In this scenario, the present paper proposes an approach for measuring synchrophasor, frequency and rate of change of frequency (ROCOF) that allows to effectively cope with abrupt transients. The method is based on Taylor-Fourier models, which typically consider a symmetric observation window with respect to the reporting instant. In this paper, the Taylor expansion is also performed on asymmetric windows, that look either at the left or at the right of the measurement instant. A robust rule enables detecting the presence of an abrupt transient, so that the best expansion is selected. Results show an exemplary behavior in amplitude and phase step tests, also in the presence of wideband noise.