New converter-fed power source to increase the dynamic performance of the three-phase electric arc furnace

The conventional three-phase electric are furnaces frequently cause undesir ed distortions in the power system, which has a low short-circuit capacity in the form of voltage fluctuations (flicker) at the point of common coupli ng. This is due to the fluctuating reactive power consumption of the furnac e. This paper describes a electronic-controlled furnace transformer which e nables the reactive power consumed by the furnace to be kept constant. This is made possible if the conventional power system of the three-phase elect ric are furnace is supplemented with three-phase power controllers and a bo oster transformer. By regulating the (reactive) power input, these disturba nces can be reduced to a minimum. This new power source was experimentally tested on a single-phase model and the results, which are presented, are ve ry satisfactory.