METHOD FOR SUPPRESSION OF ARC SHORT CIRCUITS TO EARTH IN LOAD WINDINGS AND SUPPLYING TRANSFORMERS OF THREE- PHASE SUPPLY LINE WITH NON-GROUNDED NEUTRAL WIRE

摘要

FIELD: electric engineering. SUBSTANCE: method involves measuring instantaneous levels of voltage in phases of supply line and neutral bias voltage. If arc short circuit to earth is detected, compensation of capacitance and active constituents of current of single-phase short circuit to earth is controlled. . This involves measuring amplitude and phase of electromotive force which exist between earth short circuit and neutral wire of supply line, and keeping amplitude and phase of neutral bias voltage at level which is equal to these values. Device provides possibility to suppress arc short circuits to earth in windings of electric motors, load transformers, power supply transformers regardless to method of their connection (star or delta connection) and to position of short circuit in destroyed winding. EFFECT: increased field of application. 5 cl, 7 dwg