INDUCTION-TYPE ON-LOAD STEPPING TAP CHANGER "UVAR" Russian patent published in 1995 - IPC

FIELD: electrical engineering. SUBSTANCE: tap changer has winding built up of two parallel circuits 3 and 4. Each circuit has series-connected main coil 5(6) and regulating coil 7(8). Like-polarity leads of circuits 3 and 4 are connected to one of terminals 1 of external circuit. Regulating coils of circuits have taps from same number of turns. Each of two switching systems is built up of series-connected main and auxiliary switches. Auxiliary switches 17,18 are made for changing over leads 9-16. Terminal leads of main switches 19 and 20 are connected to other terminal 2 of external circuit. With auxiliary switches 17,18 connected to leads brought out from same number of turns, load current flows through both parallel-connected circuits 3 and 4. During tap changing and continuous operation, when auxiliary switches 17,18 are connected to taps from different number of turns, circulating current is limited by opposing series connection of circuits 3 and 4. EFFECT: enlarged functional capabilities. 3 cl, 3 dwg