PMU-based power transmission line fault line selection system and method

The invention relates to a PMU-based power transmission line fault line selection system and method, and the method comprises the steps: reading transient current data from a PMU after a fault begins, comparing the transient current phase at an initial stage of the fault, determining a bus fault if the continuous change of the phase is less than 90 degrees, and otherwise, determining a feeder fault; calculating the transient energy of each feeder line based on the transient current data to serve as a main characteristic quantity, and calculating the average current amplitude difference of each feeder line to serve as a second characteristic quantity of auxiliary line selection; and calculating the fault credibility of each feeder line, wherein the feeder line with the highest fault credibility is a fault feeder line. The method has the advantages of a transient high-frequency energy calculation method and an average current amplitude difference method so that weight determination is more reasonable. The metho