Study on Identification Method of Voltage Sags for Traction Electric Network of High-speed Railway

Abstract

In view of the important factor that the EMU can’t obtain rated voltage caused by the voltage sags of traction electric network in high-speed railway, more effective feature extraction methods of voltage sag must be established to achieve rapid identification and compensation. The recognition method combined the αβ_type orthogonal expanding phase and the instantaneous dq_, type transform, can extract accurately the key characteristics of voltage sags by using the orthogonal transformation of single-phase voltage and the coordinate transformation of spreading phase voltage. The experiment show that this method can not only identify accurately the voltage sag of the traction network, but also has the advantage of clear concept and small computation.