Generalization of Methods for Voltage Sag Source Detection Using Vector Space Approach

This paper discusses methods for voltage sag source detection, which are based either on energy, current or impedance criteria. It is shown that methods known from the literature do not work well, particulary in cases of asymmetrical voltage sags. Therefore generalized methods for voltage sag source detection are proposed, using a vector space approach. All the discussed methods, both the already known and proposed ones, were tested by applying extensive simulations, as well as laboratory and field tests. The correctness of the proposed generalized methods was verified in this way. The obtained results show, that all the proposed methods are highly effective in all cases of voltage sags, whereas the overall effectiveness of those methods known from literature is mainly unacceptable.