GB436447A - Improvements in and relating to voltage and power factor control systems - Google Patents

Abstract

436,447. Transformers. BRITISH THOMSON - HOUSTON CO., Ltd., Crown House, Aldwych, London. April 5, 1934, No. 10363. Convention date, April 5, 1933. [Class 38 (ii)] The power factor of the circuit supplying current to the transformer 10, Fig. 1 is regulated by connecting condensers 18 between the minimum voltage tapping points 15 of, and the tapping switches 16 associated with, the two secondary windings 12, 13. The load circuit 14 is connected on one side to the junction of the windings 12 13 and on the other side through circuit breakers 17 to the tapping switches 16. Increases in the secondary voltage caused by operation of the switches 16 cause corresponding increases in the leading current introduced into the transmission circuit by condensers 18. In a modification the transformer 10 has one secondary winding, an associated condenser being connected between the minimum tap of this winding and the middle point of a reactor which is connected also at its middle point to one load conductor and at its ends to the tapping switches. Alternatively the primary winding and not the secondary winding is provided with tappings and associated switches and reactor. The condenser being connected between the minimum voltage tap and the reactor. In another arrangement a tapped auto-transformer 10 is employed and a series transformer 19 is arranged with its secondary winding 20 in the load circuit 14 and has its primary winding 21 connected between the middle tap of winding 12 of transformer 10 and the middle point of the reactor 22 which is connected to tapping switches 24 through circuit breakers 23. In the position shown the transformer 19 produces a negative boost in the circuit 14, the condenser 18 being connected as shown to take a leading current which increases as the voltage in circuit 14 increases. In a modification the winding 21 is connected between the tapping switches and one side of the auto-transformer the condenser 18 being connected across a tertiary winding of the series transformer 19 or alternatively being connected across the secondary winding of the series transformer 19.