GB624504A - Improvements in or relating to engine driven electric generating plant - Google Patents

Abstract

624,504. Automatic control systems for generating plant; exciting dynamos. ENGLISH ELECTRIC CO., Ltd., and BINNEY, E. A. June 18, 1946, No. 18257. [Classes 35 and 38 (iv)] In an engine-driven generating plant, the generator is at least in part excited from an amplifying generator, the output of which is varied in a sense to maintain the engine speed substantially constant. As shown, Fig. 1, the main generator field winding 1b is energized from the amplifying generator 3 (set forth in Specification 579,570), comprising the armatures 3a, 3b, and the associated fields 3d, 3e, 3c. The separately excited auxiliary generator 6, mounted on the main generator shaft, supplies the field 3e through the non-linear, negative characteristic resistor, 7. Upon a decrease of load on 1, and a consequent speed increase, a larger voltage generated at 6 is amplified at 3 and raises the excitation of 1, the output of which rises and thus tends to return the speed to the datum. In a second embodiment, (not shown), the sensitivity is increased by applying a P.D. proportional to the load current, in series opposition to the output of generator 6.