Abstract: A method for controlling a melt process in an arc furnace and signal processing component, program code, and data medium for performing said method are provided. According to the method, sound signals or vibrations from the interior of the furnace container are captured by solid-borne sound sensors, from which characteristic values can be derived for the distribution of melting material, melt, and slag in the furnace fill. A characteristic value SM for thermal radiation impinging on the furnace wall of the container, a characteristic value M for the lumpiness of the melting material in the volume of furnace fill, and a characteristic value MM for the change to the portion of solid melting material contacting the furnace wall are generated in priority sequence. The energy distribution at the electrodes is changed by a control system analyzing the characteristic values in priority sequence, such that thermal load peaks are dampened or even completely prevented.

Abstract: A reactance ballast device (V), in particular for an arc furnace, has an induction coil (1) and a free-standing load stepping switch (2), with the load stepping switch (2) being designed to adjust the reactance of the induction coil (1) while on load. A transformer (T), in particular for an arc furnace (O), has an associated reactance ballast device (V) of the type mentioned initially. An arc furnace (O), in particular for steel smelting, is preceded by a transformer (T) such as this.

Abstract: In a method for operating an arc furnace (2) with at least one electrode (3a, 3b, 3c), a solid material fed to the arc furnace (1) is melted by an arc (1) formed by the at least one electrode (3a, 3b, 3c). A measurement (MM) for the mass of one part of the solid material arranged on a boundary (2) of the arc furnace (1) is determined, and using the determined measurement (MM), a process variable of the arc furnace (1) is controlled and/or regulated. A method which can reduce the risk of electrode damage caused by metal scraps falling into the treated area is provided.

Abstract: In a method, a variable characterising an operational state of an electrode of an arc furnace can be determined. An electrode flow guided to the electrode is detected in the method and the structure-borne noise oscillations are detected. From the detected electrode flow, a flow evaluation signal associated with the frequency range of the detected electrode flow is determined. From the detected structure-borne noise oscillations, an oscillation evaluation signal that is associated with a frequency range of the detected structure-borne noise oscillations is detected and a quotient from the oscillation evaluation signal and the flow evaluation signal is formed as a radiation measurement for at least one frequency common to the detected electrode flow and the detected structure-borne noise oscillation.

Abstract: In a method for determining the size and shape value (M) for a solid material (S), in particular scrap metal, in an arc furnace (1), an electrode flow fed to an electrode (3a, 3b, 3c) for forming an arc furnace (L) between the electrode (3a, 3b, 3c) and the solid (S) is measured (30) and from the measured electrode flow (I (t)), an effective measurement value of the electrode flow is determined (31) and from the measured electrode flow (I (t)) (32), a flow part associated with a frequency range of the measured electrode flow is determined (32), and a quotient of the flow part and an effective measurement value is formed as a measurement of the shape and size value of the flow (M). Thus, a method is provided that enables a property of a fusible element introduced into one of the arc furnaces to be determined.

Abstract: A device for controlling an arc furnace installation has an automatic controller (3) wherein a functional unit (6) for furnace control, a functional unit (7) for electrode control and a functional unit (8) for melting control are integrated in the controller (3).

Abstract: A reactance ballast device (V), in particular for an arc furnace, has an induction coil (1) and a free-standing load stepping switch (2), with the load stepping switch (2) being designed to adjust the reactance of the induction coil (1) while on load. A transformer (T), in particular for an arc furnace (O), has an associated reactance ballast device (V) of the type mentioned initially. An arc furnace (O), in particular for steel smelting, is preceded by a transformer (T) such as this.