| 摘要 |
<p>PURPOSE:To reduce a loss in operation and improve the productivity by calculating the ratio of the moving amount of a movable electrode to the change amount of an arc voltage, and controlling the electrode moving amount based on the relation between this ratio and evaluation coefficients. CONSTITUTION:A high voltage is applied to a movable electrode 4, and a scrap 2 is fused while an arc is generated from the electrode 4 top end. In this case, a detected voltage Vr of an arc voltage detector 11 and an electrode position signal H from a position sensor 21 are supplied to a voltage change amount calculating means 22. The means 22 determines the change amount of the detected voltage V, which is then sent to an electrode speed judging means 23. The means 23 judges whether the change amount had the relation of k1< V<k2 or not using evaluation coefficients k1, k2 when the electrode is raised, and outputs a signal for reducing the electrode raising speed when it does not have this relation. When the change amount V is larger than an evaluation coefficient k3 in the electrode falling control, a judgment signal for increasing the electrode falling speed is outputted. Hence, a proper position control of the electrode 4 can be carried out, considering the state within an arc furnace 1.</p> |
