DETECTION METHOD FOR DETECTING SMALL-CURRENT SINGLE-PHASE GROUND FAULT IN 10 KV DISTRIBUTION NETWORK

摘要

A detection method for detecting a small-current single-phase ground fault in a 10 kV distribution network, the method comprising the following steps: (1) performing data acquisition by tracking and accumulating outgoing line scheduling and measurement data of distribution network lines in normal operation over a long period of time, acquiring data of operating TTUs and negative control terminals of the lines, and accordingly calculating the power loss level of each outgoing line of the distribution network under different loads; (2) analyzing correlations between various variables, and establishing a normal-state loss model for each outgoing line of the distribution network and a ground fault loss model for single-phase grounding; and (3) identifying a faulty phase line by means of measuring voltage values on an open-delta PT secondary side of each substation bus. The detection method uses steady-state big data analysis to monitor automatic operation of 10 kV distribution network lines, thereby achieving line selection and fault identification and prediction with respect to small-current ground faults.