Current supply device for electrically heating a molten medium

摘要

A system for generating in-phase alternating current components which are fed into a medium held in a melting trough and flow in the medium between electrodes and counterelectrodes immersed in the medium to effect resistance heating. One embodiment of the system includes a supply voltage source, and a plurality of transformers each having a primary winding and a secondary winding, with the primary windings being connected together in series and to the source, each secondary winding being connected between a respective electrode and counterelectrode to provide a respective alternating current component, and each winding having a number of turns corresponding to the desired relative amplitudes of the current components. A second embodiment of the system includes a supply voltage source, at least one input transformer having a primary winding connected to the source and at least one secondary winding, and a plurality of additional transformers each having a primary winding and a secondary winding, with the primary windings of the additional transformers being connected together in series and in a closed loop, each secondary winding of the input transformer being connected in series with at least one secondary winding of the additional transformers between a respective electrode and counterelectrode to provide a respective alternating current component, and each winding of the additional transformers having a number of turns corresponding to the desired relative amplitudes of the current components.