| 摘要 |
PROBLEM TO BE SOLVED: To provide a ground fault detection/display device low in price without being structured as a ground fault zone detection system. SOLUTION: In the ground fault detection/display device, current detectors 40a, 40b and 40c that detect line currents are arranged at arbitrary points of a three-phase distribution line 2 drawn out of a substation 1, and a voltage detector 41 that detects a prescribed inter-line voltage of the distribution line as a reference inter-line voltage is arranged in the device. The device also comprises a phase comparison circuit 423 that compares the reference inter-line voltage detected by the voltage detector and a phase of a zero-phase current calculated from the line current detected by the current detector, determines whether the zero-phase current has a leading phase or a delayed phase, and calculates a phase difference. The phase comparison circuit is further provided with a ground fault indicator 41 that encodes the determined leasing phase or the delayed phase and the calculated phase angle, and when a ground fault accident is determined, displays the encoded code information. COPYRIGHT: (C)2007,JPO&INPIT
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