HIGH-VOLTAGE CABLE GROUND FAULT DETECTION CUT-OFF CIRCUIT IN POWER RECEPTION/DISTRIBUTION FACILITIES SYSTEM

摘要

To provide a high-voltage cable ground fault detection cut-off circuit in a power reception/distribution facilities system capable of reducing a time required for change in a method and simplifying a change work by preparing a configuration to switch to a method of zero phase voltage detection by ZVT and zero phase current detection by EVT of a base block of a power reception/distribution facilities system from a method of zero phase voltage detection by ZVT and zero phase current detection by EVT for an electric power company distribution station when ZVT and EVT are provided in the base block and predetermined conditions are met.SOLUTION: A high-voltage cable before being supplied to a base block is provided with an electric power company power distribution station EVT 1. Connection means capable of connecting an insulation transformer to an intermediate section in the base block is provided. Further, it is configured to extend through a high-voltage circuit breaker and connect to a high-voltage cable that activates other base block or a G/C or the like. A ZVT for detecting a zero phase voltage, an EVT for forming a ground fault current circuit, a ZCT for detecting a zero phase current, and an AND circuit for taking a logical product of a detection signal of a zero phase voltage and a zero phase current, and a relay are provided.SELECTED DRAWING: Figure 1A