| 摘要 |
533,455. Field control of D.C. motors. AKT.- GES. BROWN, BOVERI, & CIE. Sept. 29, 1939. No. 26896. Convention date, Oct. 17, 1938. [Class 38 (iii)] Varying E.M.F.- A motor 7 driving a vehicle and fed from generator 6 driven by a diesel engine 19 has a field-winding 10 separately-excited from a source 8 and controlled automatically in accordance with the speed or armature voltage of the motor, so that with increasing voltage or speed the excitation is reduced. The control may be effected by resistance regulator in the field or by supplying the field through a circuit including an opposing voltage proportional to the armature voltage. Such a voltage may be tapped from a resistance 9, or provided by an exciter driven by the motor. The generator characteristic is preferably selected which conforms to the most economical engine characteristic over a speed range. Braking is effected with the motor returning current to the generator, and in addition a resistance may be connected across the motor when the motor voltage falls below that of the generator. |
