Increased energy efficiency in MF induction melting furnaces by optimized operation

The introduction of static frequency converters in the 1980’s caused a new impetus to inductive melting. Medium-frequency crucible furnaces have since become established as standard melting systems, particularly in iron foundries [1]. The higher, adaptable frequency of the coil current enables crucible furnaces fed by converters to be operated in batch type mode at a much higher power density and without any loss of melting performance, even if the furnace is emptied completely each time. Apart from economic gains and technical process benefits, a particular advantage is that energy efficiency can be increased compared to crucible furnaces operated at line frequency. After a brief characterization of medium-frequency inductive melting technology, this paper goes on to describe how this increase can be optimized by means of action concerning operation processes and the system itself.