SAFE OPERATIONAL METHOD FOR REDUCING VOLTAGE AND ELIMINATING PHASE ARCING OF EARTH FAULT OF SWITCHED OFF GROUNDING SYSTEM Russian patent published in 2020 - IPC H02J3/12 H02H9/00 

FIELD: electrical engineering.

SUBSTANCE: use: in electric power engineering. Present invention discloses a method of safe operation for reducing voltage for damping the phase of occurrence of earth fault of a system of inefficient grounding for use for safe operation with earth fault of a neutral point of a generator with inefficient grounding or distribution network. In case of single-phase ground fault on the side of system of inefficient grounding, external voltage source is used between bus and grounding, between line and grounding, between neutral point and grounding or between shunting stage of transformer winding on side of system of inefficient grounding and grounding to reduce phase-to-ground phase voltage so that it is less than the value of long-term electric winding of the grounding electrode, thus meeting the requirements of long-term continuous safe operation.

EFFECT: technical result is provision of elimination of instantaneous single-phase ground fault, damping of long-term current of single-phase earth fault, limitation of growing amplitude of phase voltage without short-circuit and risk of breakdown of insulation of this phase, reduced risks for safety of people and equipment, efficient prevention of failures at power outages and improvement of reliability and safety of power supply.

10 cl, 1 tbl, 6 dwg