Novel Application of Detrended Fluctuation Analysis for State Estimation Using Synchrophasor Measurements

The phasor measurement unit (PMU), with its ability to directly calculate synchronized positive sequence voltages and currents (magnitude and phase), offers a more current and accurate view of the power system compared to that provided by traditional measurements and state estimation (SE). However, the high-resolution data, provided at rates of 50 Hz and 60 Hz (dependant on nominal frequency), capture any transient or dynamic events occurring on the network, potentially distorting the intended steady-state view at various points of the power system. In this paper we propose the use of detrended fluctuation analysis (DFA) to detect and isolate such events for alternative investigation. Comparisons are made between the state estimator and installed PMUs on the high-voltage transmission system of Great Britain.