Arc-furnace control by regulex exciters

FOR a number of years prior to the present urgency for the production of high-quality steel, the development in control methods for electric-arc furnaces remained substantially stationary in this country. These devices were in the general form of vibrating regulators or contact-making ammeters which rapidly connected the electrode motors to and disconnected them from a constant d-c voltage source. In Europe, meanwhile, various methods employing Ward-Leonard or hydraulic control means were developed, some of which were reported to result in smoother operation under the highly fluctuating transient conditions of the arc.