GB191107045A - Improvements in and connected with Continuous Electric Current Generators with Separate Excitation. - Google Patents

Abstract

7045. Krupp Akt. - Ges., F. May 18, 1910, [Convention date]. Exciting. -In a Ward-Leonard system in which continuous-current motors are driven by a series generator having also separate excitation, the generator is provided with an additional counter-compounding coil carried by an auxiliary magnet-frame, which is saturated when the series current is relatively small. The motors are thereby brought to rest with certainty, and are caused to take a small standstill current when the separate excitation of the generator is switched off. The machine has small auxiliary poles F, Fig. 3, carrying the series current and so wound as to oppose the main poles H magnetically, the latter poles having additional coils for separate excitation. The magnetization curve of the counter-winding K is steeper than that of the main winding D, and then rapidly bends over to saturation. The volt-ampere characteristics for such a generator are shown in Fig. 1, in which the line Ml gives the volts required solely for overcoming the resistance of the motor circuit. The lines Cc, Cd<1>, Cn<1> respectively indicate the volts due to the residual field, the residual field plus the additive compounding, and the residual field plus the additive and auxiliary counter-compoundings. It is shown in the Specification that the standstill current of a motor driven by such a generator may be reduced from the value FG to F'G'. When the generator separate excitation is switched on, the voltage curve is, as shown at p, parallel to and slightly above the resistance line Ml, from which it follows that the generator will drive motors stably, even at slow speeds. disks clamped together produce a hollow cylinder with radiating arms a' and a rim a<3>, the openings therethrough having stepped sides a<5> making an acute angle with the plane of the disks. The stepped sides may be filed or machined.