GB670782A - Dynamo-electric machine for regulation - Google Patents

Abstract

670,782. Exciting dynamos; boosting. SOC. ITALIANA E. BREDA PER COSTRUZIONI MECCANICHE. Dec. 6, 1948 [Dec. 6, 1947], No. 31576/48. Classes 35 and 38 (iv). By providing similarly excited coils on saturated and unsaturated parts of its field core to give a differential effect, the voltage of a generator can be built up positively or negatively and the voltage variations are amplified by deriving from the armature a supplementary exciting current. The saturated core with its field coil can be replaced by a permanent magnet. As shown in Fig. 1, the opposing windings 1, 2 give no resultant flux at a predetermined value of exciting current but at higher values, winding 2 on the unsaturated core part 5 will more than neutralize the effect of winding 1. The core 5 may carry another winding 17 which may be fed as shown in Fig. 5 when the machine acts as an exciter 18 for a battery-charging generator 15, and the exciter has a winding 10 fed from the armature. The booster 19 for maintaining constant volts across the lamps 21 may be similar to the exciter and driven with it by a motor 22. The machine could also be used as the exciter of an alternator.