METHOD OF DETERMINING SINGLE-PHASE GROUND FAULT IN NETWORKS OF 6-10 kV WITH INSULATED NEUTRAL LINE

摘要

FIELD: electrical engineering.;SUBSTANCE: invention relates to electrical engineering, namely to determination of single-phase ground fault (SPGF) in 6–10 kV networks with insulated neutral. Voltage measurement devices record values of phase voltage at the beginning and at the ends of the power line and register voltage values of the damaged phase in steady-state conditions. Signals are transmitted to a control station, where they are jointly processed by a differential method, according to which the analyzed line is pre-modeled in the Matlab Simulink program and the functional connection L=f(U1-U2), where L is the distance to SPGF from the beginning of the line (km), U1 is the voltage value of the damaged phase in steady-state mode at the beginning of the line, U2, U3, etc. is the value of voltage of the damaged phase in steady-state mode at the ends of the line. By substituting the measured values into equations, it is determined on which branching there occurred a short circuit and what is the distance to it from the beginning of the line.;EFFECT: high reliability and accuracy of determining the point of damage in an overhead power line, reducing the cost of equipment owing to recording a steady-state process and eliminating the need for synchronization of recording devices in time.;1 cl, 1 dwg