The intermediate frequency electric furnace is a power supply device that converts the power frequency 50HZ alternating current into the intermediate frequency (300HZ above to 10000 HZ), which is composed of frequency conversion device, furnace body, furnace front control and other parts. Using the principle of electromagnetic induction, the raw materials in the furnace are heated, and the steel raw materials in the alternating magnetic field will generate a large "eddy current" current due to cutting the magnetic lines of force, and then heat and melt.