ELECTRODE ASCENT AND DESCENT CONTROL DEVICE FOR ALTERNATING CURRENT ELECTRIC ARC FURNACE AND METHOD THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide an electrode ascent and descent control device for an alternating current electric arc furnace which can be operated under not more than the rated capacity of a furnace transformer and a method therefor by controlling an electrode current within not more than the rated value of an electrode from a receiving end facility through the intermediary of a series reactor and the furnace transformer. SOLUTION: An electrode ascent and descent control device 20 comprises analog multipliers 11, 12, 14, 21, 23 analog adders 13, 15, an electrode ascent and descent control circuit 16 and an analog devider 22, and is adapted to control the arc length of an alternating current are furnace 5 by amending a reactor correction constant based on a drop in the electric voltage of a series reactor 1 in the case of the rated capacity of a furnace transformer 3 into a value based on the drop in the electric voltage of the series reactor 1 under an actual operation condition of the alternating current electric arc furnace 5 which is calculated with the analog multipliers 21, 23 and the analog devider 22.