A plant for melting and/or heating metal material includes a furnace, electrical energy feed means and an electric power apparatus connected between the feed means and the furnace; and a corresponding method to power the melting and/or heating plant.

A power supply system for an electric arc furnace includes an AC input connectable to an electrical grid and an AC output for supplying at least one power electrode of the arc furnace; a resonant circuit interconnected between the AC input and the AC output. The resonant circuit includes a controllable bypass switch for connecting and disconnecting a circuit input and a circuit output of the resonant circuit and a capacitor and a main inductor connected in parallel with the bypass switch.

A control system includes a vision system including an imaging device and a VAR monitoring system configured to determine a power adjustment phase of the VAR process based on the images from the vision system and a process parameter. The VAR monitoring system includes a vision analysis module configured to analyze the images from the vision system to detect a melt marker based on a remelt image process model, and a prediction module configured to predict an operational characteristic of the VAR process that is associated with the power adjustment relative to a melt marker location and a remelt prediction model. The VAR monitoring system is configured to initiate the power adjustment phase in response to the melt marker satisfying a predetermined melt marker condition, the operational characteristic of the VAR process satisfying a predetermined operational condition, or a combination thereof.

A supply device for a high-power load includes a DC/DC voltage converter disposed between a high-voltage side and a low-voltage side. The DC/DC voltage converter includes a first sub-converter and a second sub-converter. The sub-converters are connected to one another in a converter series circuit between first and second primary-side DC voltage poles. The second sub-converter is connected between first and second secondary-side DC voltage poles. The sub-converters each have at least one AC voltage terminal connected to one another by a coupling device to permit an exchange of electrical power between the first and second sub-converters. The secondary-side DC voltage poles are configured for connection to the high-power load. An arrangement for converting electrical energy into chemical energy with gas generation includes the supply device.

A supply device for a high-power load includes a DC/DC voltage converter disposed between a high-voltage side and a low-voltage side. The DC/DC voltage converter includes a first sub-converter and a second sub-converter. The sub-converters are connected to one another in a converter series circuit between first and second primary-side DC voltage poles. The second sub-converter is connected between first and second secondary-side DC voltage poles. The sub-converters each have at least one AC voltage terminal connected to one another by a coupling device to permit an exchange of electrical power between the first and second sub-converters. The secondary-side DC voltage poles are configured for connection to the high-power load. An arrangement for converting electrical energy into chemical energy with gas generation includes the supply device.

A power supply system for an arc furnace, suitable for converting voltage of a three-phase electric power network into power supply voltage for the arc furnace, has an indirect AC/AC converter having a converter input and a converter output, and a matching apparatus having a matching transformer having a secondary side connectable to the arc furnace and a primary side operatively connected to the converter output. An input transformer group, inserted between the indirect AC/AC converter and the three-phase electric power network, has an input transformer primary side connectable to the three-phase electric power system, an input transformer secondary side connected to the converter input, a first input transformer and a second input transformer. Each of the first and second input transformers has three mutually displaced groups of secondary windings, each of which has a winding for each phase corresponding to a phase of the three-phase electric power network.

A power supply system for an electric arc furnace includes an AC input connectable to an electrical grid and an AC output for supplying at least one power electrode of the arc furnace. The power supply system further includes a converter circuit interconnected between the AC input and the AC output. The converter circuit includes at least one converter cell with a capacitor and semiconductor switches for series connecting the capacitor between a circuit input and a circuit output of the converter circuit.

A method for identifying, classifying, and sending notification of an electric arc furnace's (EAF) anomalies to improve the EAF efficiency. The method includes the steps of establishing baseline state measurements of the EAF, receiving new state measurements of the EAF and statistically testing the new state measurements against the baseline state measurements. The method further includes the steps of identifying as an anomaly a failed statistical test, classifying the identified anomaly and sending notification of the classified anomaly to a configurable list of recipients.

A melting method including a step of loading solid metal material into an electric furnace, a step of generating an electric arc between at least one electrode and the metal material, a step of perforating the metal material during which the electrode is moved through the metal material, a step of melting the solid metal material in order to obtain a molten material, and a step of refining the molten material by adding reaction compounds. At least one of the steps includes regulating the electric parameters of the electric arc.

A melting method including a step of loading solid metal material into an electric furnace, a step of generating an electric arc between at least one electrode and the metal material, a step of perforating the metal material during which the electrode is moved through the metal material, a step of melting the solid metal material in order to obtain a molten material, and a step of refining the molten material by adding reaction compounds. At least one of the steps includes regulating the electric parameters of the electric arc.