Oscillation suppression system for furnace - prevents arc-furnace electrode-arm oscillating, by reducing proportional gain of impedance controller according to arc current fluctuation

摘要

The suppression system prevents the arm supporting the electrode of an arc furnace from oscillating as a result of periodic fluctuations in the arc current. (Such oscillations can cause the electrode to break). The proportional gain of the impedance controller is reduced depending on the fluctuations in arc current. To this end, the control difference is passed to the controller via an attenuator that reduces it by an amount depending ondthe periodic fluctuations superimposed on the control difference.