Models for Synchrophasor With Step Discontinuities in Magnitude and Phase: Estimation and Performance

Abstract

This paper proposes models for the reference phasor in the context of phasor measurement unit calibration, under conditions of step discontinuities in magnitude and phase, along with methods to estimate the model parameters. Two parametric mathematical models, which are proposed to represent these signals, are fitted to signal samples via an iterative numerical method. The proposed approach does not require any time adjustment of the analysis window to skip the discontinuity. The estimated parameters can be used to calculate the frequency, the magnitude, and the phase during magnitude or phase steps. During a window with the step transient, we propose reference phasors with an appropriate definition. Moreover, we quantify the errors of the phasor-related estimates, for both computer-simulated cases and laboratory measurements.