METHOD AND DEVICE FOR SUPPLYING AN ELECTRIC ARC MELTING FURNACE WITH CURRENT

• Main Authors: SCHMALE, KLAUS, GRUND, GUIDO, BREKER, DIRK, ESPENDILLER, BERNHARD
• Format: Patent
• Language: English; French; German
• Published: 23.01.2002
• Edition: 7
• Subjects: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC,OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWERSUPPLY SYSTEMS; BLASTING; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTINGELECTRIC POWER; CONTROL OR REGULATION THEREOF; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUTPOWER; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRIC HEATING; ELECTRIC LIGHTING NOT OTHERWISE PROVIDED FOR; ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; FURNACES; FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; GENERATION; HEATING; KILNS; LIGHTING; MECHANICAL ENGINEERING; OPEN SINTERING OR LIKE APPARATUS; OVENS; RETORTS; SYSTEMS FOR STORING ELECTRIC ENERGY; WEAPONS

The invention pertains to a process and to a device for supplying current to an electric-arc melting unit for melting and heating metal, especially steel, with a three-phase a.c. source, which sends the current via devices for producing direct current or alternating current to at least one electrode projecting into the vessel of the melting unit. The three-phase a.c. source (91) is followed by at least two power supply modules (41, 4n), connected in parallel, where each power supply module (41; 4n) has an uncontrolled three-phase bridge (51, 5n), a direct-current intermediate circuit (61, 6n), and a transistor unit (71, 7n) connected in series, and where, downline from the power supply modules (41, 4n) in the current flow direction, a common current-carrying line (31) leads to at least one electrode (21) of the melting unit (11) and away from at least one other electrode (22, 24).