Evaluating Conventional Power Swing Blocking Methods

This research focused on conventional power swing blocking (PSB). The conventional PSB methods are tested with various fault conditions such as fault location and fault type scenarios consisting of stable and unstable power swings. PSB methods developed in MATLAB have been implemented on a two source test system simulated in PSCAD. Measurements taken from the reference bus are transformed to phasors using half cycle discrete fourier transform and they constitute the fundamental of the PSB methods. The methods used in this paper are as follows; decreasing resistance, swing center voltage, superimposed, and change of active and reactive power PSB methods. Threshold values for each PSB method are determined based on stable and unstable power swing conditions. The methods of the superimposed and change of active/reactive power are observed to be the most accurate ones while those of the decreasing resistance and swing center voltage found to be suffered from unstable power swing test conditions. This study revealed the importance and restriction of threshold determination.