| 摘要 |
1,193,308. Control of D.C. motors. LICENTIA PATENT-VERWALTUNGS-G.m.b.H. 28 June, 1967 [30 June, 1966], No. 29858/67. Heading H2J. [Also in Division G3] D.C. traction motors 4a, 4b are supplied via controlled rectifiers 3a, 3b from a three-phase, separately excited generator 2 driven by a variable speed diesel engine 1. Firing of the rectifiers is determined by the difference between the actual power delivered to the motors, as determined at 6 by the product of the current measured at 14 and the voltage at 16, and a reference value produced by function generator 5 in dependance upon the speed of the generator as measured by its frequency at 15. The function generator is designed so that the diesel operates at its optimum power output for the speed at which it is running. The power difference is amplified at 7, the output of which may be opposed by a current limit device 12 or a wheel slip detector 11 which detects misbalance between motor currents. After further amplification at 8 the signal controls a firing circuit 9a directly, and another 9b via a device 10 which causes less power to be delivered to the leading driving axles. The generator 2 has a voltage-speed characteristic rising steeply in the lower speed range and less steeply thereafter. Each rectifier may supply one or more motors. The firing circuits comprise transistors or thyristors which deliver either individual pulses or trains of pulses. |
