GB623873A - Improvements relating to the automatic regulation of alternating current dynamos working in association with batteries - Google Patents

Abstract

623,873. Automatic voltage control of variable speed alternators. ROTAX, Ltd., and HAMILTON, R. F. G. May 22, 1947, No. 13760. [Class 38 (iv)] An automatic regulator for an alternator 2 supplying a load 4 and battery 3 through a rectifier 5, more particularly for maintaining close regulation over wide ranges of speed and load, comprises a variable resistor, such as a carbon pile 11, 12, varied in response to the battery voltage and controlling direct current saturation of a saturable reactor 8, 10, through which the field 1 of the alternator is fed over rectifier 9. Adjustable magnetic bias may also be applied to the reactor by a further D.C. winding energized from the battery through a rheostat and opposing the winding 10. Field excitation may also be provided in part, by current transformers 7 in the alternator output leads, the transformers feeding recti. fiers 6. A switch 13 and resistor 14 permit excitation from the battery, when required. To reduce the variation required of the pile 11, the saturating circuit may be energized from across the field. circuit. Instead of the current transformers 7 and rectifiers, a winding assisting winding 10 and carrying the rectified output current of the alternator may be provided on the reactor.