DIAGNOSIS OF INSULATION DETERIORATION OF HOT-LINE CABLE

摘要

PURPOSE:To make it possible to more accurately judge the insulation deterioration of a power cable during a hot-line state by applying positive and negative DC voltages between the conductor of a cable to be measured and the earth while calculating the difference of positive and negative currents. CONSTITUTION:Positive and negative DC voltage are applied between the conductor of a power cable 4 to be measured under a hot-line state and the earth through the primary side neutral point of the earthing transformer 3 of a power distribution bus 2 by a DC power source 7 to measure positive and negative currents flowing the cable 4 by a measuring device 8 while the difference of the positive and negative currents are calculated. This data is transmitted to a master station 11 from a slave station 9 to monitor an insulation deteriorated state in a hot-line state.