Research on Location and Recognition Method of Voltage Sag Disturbance

The accurate positioning of the voltage sag disturbance source relative to the monitoring point helps to clarify the responsibilities of both parties. This paper proposes a brand-new single-frequency cross S-transform perturbation power positioning method for locating voltage sag disturbance sources. First, the voltage and current signals collected at the monitoring point are transformed into a single fundamental frequency S to obtain a complex vector of the fundamental frequency of the voltage and current; then, the complex vector of the voltage and current fundamental frequency is subjected to a single fundamental frequency cross S transformation. The module extracts the instantaneous apparent power, and then obtains the instantaneous apparent disturbance power; finally, the disturbance power criterion is used to locate the source of the voltage sag disturbance. Through analyzing and judging the monitoring point of the problem caused by short circuit fault, the result proves the accuracy and effectiveness of the proposed method.