Do system impedances really affect power swings — Applying power swing protection elements without complex system studies

One of the traditional techniques for detecting power swings uses a dual-quadrilateral characteristic. It is based on the measurement of the time interval it takes the positive-sequence impedance to cross two blinders. Another technique monitors the variation of the swing center voltage approximation. This paper presents a performance comparison between applications of these two techniques in cases derived from a sample network transient simulation and in cases recorded during real operations in the field.