Impact of Asymmetrical Disturbance Events on Voltage Sag Source Detection

Abstract

Methods for voltage sag source detection based either on energy or current criteria are discussed in this work. They are tested by applying extensive simulations and field tests. The obtained results show severe impact of asymmetrical disturbance events on voltage sag source detection, particularly in cases of upstream ground faults. However, all discussed methods show very high effectiveness in cases of voltage sags due to heavy motor starting and other symmetrical voltage sags. Based on the performed evaluation it can be concluded, that further development is still needed to increase the degree of confidence in the discussed methods for voltage sag source detection.