FIELD: power engineering.
SUBSTANCE: invention relates to the electric power industry and is intended for use in the search for a ground fault (GF) location in the high voltage line (HVL) in the operating mode of the network. Reveal a HVL ground fault phase. Periodically transfer the HVL from single-phase GF mode to dual double-earth GF mode and vice versa by connecting and disconnecting the adjacent operational HVL phase with ground through the current-limiting resistor. Transfer of HVL from single-phase GF mode to double GF mode and the reverse is performed remotely by commands of the operational-visiting brigade in the process of short stops on the HVL path at the moments of zero crossing, respectively, of the voltage and current of the zero sequence, ahead of time for the production of these operations. Zero-sequence pulsed current superimposed on the capacitive current of the overhead line is controlled. Required position of the GF to HVL is fixed at the boundary between the zone of presence of jumps of the impulse superimposed current and the zone of their absence. Invention makes it possible to improve the accuracy of the location of the GF using widely used current topographic portable pointers.
EFFECT: providing high sensitivity and selectivity, which increases the speed of the search for a ground fault location.
5 cl, 4 dwg
