Furnance Transformer

The induction furnace has a coil of heavy copper tubing. Designed and tuned to the inverter circuit which applies medium frequency voltage (usually 500 Hz or 1000 Hz) to the Induction coil. Eddy currents induced in the charge by the magnetic field of the induction coil heat the charge. A medium frequency is needed to increase the rate of heat generation.

The operation of the inverter circuit requires a D.C. Voltage obtained from available three phase A.C. voltage. Induction Furnace Transformers: The transformers used to convert available three phase A.C. voltage to required voltage for converter circuit of the Induction Furnace are called as Induction Furnace Transformers. So basically they are Rectifier/Converter Duty Transformers.

These transformers have to be designed to withstand the high levels of electrical, thermal and mechanical stress to which they are subjected during utilization.

Thus the furnace transformer has special features to deal with such high currents compared with conventional transformers. The electric arc furnace has 3 electrodes which are connected to the secondary terminals of the furnace transformers.

The secondary terminals of the transformers are short-circuited by the charge and arc during the melting process. Therefore, the furnace transformer must be specially designed to withstand the frequent short circuit.