METHOD OF DISCRIMINATING FAULT LINE AND FAULT PHASE IN UNGROUNDED DISTRIBUTION SYSTEM BY USING ZERO PHASE VOLTAGE OF BUS AND ZERO PHASE CURRENTS OF EACH LINE

摘要

PURPOSE: A method of discriminating a fault line and a fault phase in an ungrounded distribution system is provided to discriminate easily a fault line by comparing a zero phase voltage of a bus with zero phase currents of each line. CONSTITUTION: A zero phase voltage detection process is performed to measure a zero phase voltage of a bus for a system. A zero phase current detection process is performed to measure zero phase current of each line. A phase of the zero phase voltage of the bus is compared with a phase of the phase current of the lines. A fault line is determined according to a compared result between a phase of a zero phase current for a particular line and the phase of the zero image voltage.