GB190325053A - Improvements in Electric Lighting and Power Systems. - Google Patents

Abstract

25,053. Milne, G. G. Nov. 17. Dynamos, regulating.-In a train or other electric lighting or power system in which a main generator is driven at variable speeds and is liable also to have its rotation reversed, the current from the generator is kept constant in value and direction by the use of a regulating-generator C driven with the main generator A and supplying variable current to the field of a motor F which drives the exciter D of the generator A. The field currents of the generators C, D and the armature current of the motor F are taken from a constant source, such as the storage battery B' of the lighting-system. When the speed of the shaft a' falls, the current supplied to the motor field also falls, so that the generator D is driven at an increased speed to supply an increased field current to the generator A. If the rotation of the shaft a<1> reverses, the field current of the motor F reverses, thus causing the motor to reverse and also causing the generator D to supply a reversed current to the generator A ; the main current thus continues as before. The motor F is preferably worked at a low degree of saturation, and an automatic switch I may be arranged in the motor armature circuit as shown, to prevent the generator A from being excited until the speed of the shaft a<1> is sufficiently great for the generation of the proper electromotive force in the generator A.