GROUND FAULT PHASE DETECTOR AND GROUND FAULT PHASE DETECTION METHOD

摘要

PROBLEM TO BE SOLVED: To provide a ground fault phase detector and a ground fault phase detection method that are capable of detecting a ground fault phase.SOLUTION: A ground fault phase is detected using a neutral potential of three-phase transmission line to be monitored and each potential of three phases of reference distribution line. Therefore, a ground fault phase detector 10 is configured to comprise first to third phase voltage conversion means 21 to 23, first to third determination means 31 to 33 and display means 40. The first to third phase voltage conversion means generates first to third DC voltage signals with a size corresponding to a phase difference between the neutral point of three-phase transmission line and each potential of the first to third phases of reference distribution line, respectively. The first to third determination means determines whether or not each voltage value of the first to third DC voltage signals falls within a predetermined range, respectively. The display means determines the ground fault phase based on the result of determination by the first to third determination means to display it.