GB497653A - Improvements in and relating to transformer voltage regulators - Google Patents

Abstract

497,653. Automatic regulation; boosting transformers. BRITISH THOMSONHOUSTON CO., Ltd. June 18, 1937, No. 17048. Convention date, June 20, 1936. [Class 38 (iv)] The voltage of an A.C. circuit A, B, N is regulated by a boosting transformer having its series winding or windings 4, 4<1> connected in this circuit and its exciting winding or windings 9 connected to A, B through a switching device 7, one of the windings 5 other than a series winding having a device 8 connected across it, this device being of such a character that increase of the voltage applied to it causes a considerable decrease in its impedance, whereby the impedance of the series winding 4, 41 is limited during operation of the switch 7. The switch 7 may be operated by an electromagnet 10 to energize the winding 9 when the circuit voltage falls below the required value and the resonant circuit 15 becomes dissonant, relay 19 being allowed to close its contacts. On rise of the voltage above the required value, the circuit 15 which comprises saturable reactor 17 and condenser 18 beoomes resonant and relay 19 is energized to de-energize electromagnet 10, the switching device 7 being then operated to short-circuit the exciting winding 9. The winding 4<1> is omitted on applying the arrangement to a two wire A.C. circuit. The winding 5 may be connected in series with winding 9 to act as a second exciting winding and may, for example, be connected so as to assist or oppose the winding 9 in one position of the switch 7, one of the windings 5, 9 being disconnected or short-circuited in the other position of the switch 7. A large number of alternative methods of connecting the windings 5 and 9 with switching device 7, each giving a different range of regulation, are described in the Specification. Specification 292,110, [Class 38 (iv)], is referred to.