GB631697A - Regulated power supply equipment comprising parallel connected rectifiers - Google Patents

Abstract

631,697. Rectifying; automatic regulation. STANDARD TELEPHONES & CABLES, Ltd. June 13, 1947, No. 15646. Convention date, March 10, 1943. [Classes 38 (ii) and 38 (iv)] Regulated power supply equipment comprises rectified units L1-L4 adapted to supply in parallel a D.C. load circuit from an A.C. supply and provided with D.C. saturable reactors having regulating windings V1-V4 in their A.C. supply circuits and is characterised by a cascade connection of the rectifier units whereby the units are successively brought into use as the load increases, the rectified current from one rectifier unit passing through a regulating winding on the reactor of the succeeding rectifier unit with the exception of the last unit the rectified current of which traverses no other unit. When the voltage output of the rectifier unit L1 is higher than that of the remaining units it only supplies the load circuit but as the load increases the output voltage of the rectifier unit L2 increases (if the winding V2 has the appropriate direction of magnetization) until it equals that of the unit L1 at which point the unit L2 begins to supply current to the load circuit. Further increases in load current bring the rectifier units L3, L4 into operation. The load voltage will, however, always be determined by the voltage of the rectifier unit L1 which may' have a smaller output rating than the remaining rectifier units and which may be regulated by any suitable means, manual or automatic. The system may also be arranged to be selfregulating without the provision of additional means to the first rectifier unit by a suitable choice of voltage/current characteristic for the rectifier units so that the load voltage may increase, decrease or remain constant as the load current increases. The characteristic of each unit may be given a particular form by providing its associated 'reactor with an additional winding supplied with feed-back from the rectifier unit output. A stabilizing device S may be included so that a constant D.C. output voltage may be obtained independent of any A.C. supply voltage fluctuations which D.C. voltage may be regulated manually by tappings on a transformer TR1 or on an additional transformer placed in circuit before the reactor R1. The equipment may be provided with any known system of automatic regulation on the first rectifier unit based on, for example, the output voltage or current.