ELECTRICAL NETWORK NEUTRAL GROUNDING CONTROL METHOD Russian patent published in 2023 - IPC H02H9/08 

FIELD: electrical engineering and electrical energy industry.

SUBSTANCE: invention relates to electrical engineering and electrical energy industry and may be used in electric distribution networks with insulated neutral points. The factors given in the technical results make it possible to increase the reliability of power supply by significantly reducing the risk of electrical and fire hazards and equipment failure. Technical result in the first engineering solution is achieved by introducing compensation current into neutral network at single-phase ground-fault, at occurrence of single-phase ground-fault create the phase artificial ground-fault circuit, measure current in the phase artificial ground-fault circuit, determine instantaneous ground-fault current, reproduce it in neutral network and the phase artificial ground-fault break circuit. Technical result in the first engineering solution is achieved by injecting a compensation current into neutral network at single-phase ground-fault, at occurrence of single-phase ground-fault create the phase artificial ground-fault circuit, measure current in phase artificial ground-fault circuit, determine instantaneous ground-fault current, reproduce it in neutral network and the phase artificial ground-fault break circuit. The neutral network compensation current can be injected by means of an adjustable source connected to the neutral network with the possibility of its adjustment by a signal extracted from the determined instantaneous ground-fault current. Technical result in the second engineering solution is achieved by injecting the compensation current formed from the currents in the phase ground-fault circuit and in the neutral earthing reactor circuit, the instantaneous ground-fault current shall be determined, reproduced in the network neutral, and the phase artificial ground-fault circuit shall be opened.

EFFECT: invention provides a possibility of fast and accurate monitoring of single-phase ground-fault current and monitoring its compensation, whatever its components are at the ground-fault point.

5 cl, 3 dwg