Principle of Induction heating: The basic principle of induction heating is that, supply is given to primary winding of furnace transformer & heat is produced in the secondary (charge) due to electromagnetic action.
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Principle of Induction heating: It is based on principle of transformer. In this type primary winding is as usual which is wound around one limb of magnetic core but secondary winding is actually charge which is to be melted is kept in crucible. When AC Supply is given to primary winding current flows through primary winding which creates alternating flux in magnetic core this flux links to the secondary winding i.e. charge through magnetic core. Hence according to faraday’s law of electromagnetic induction emf will be induced in secondary winding, that is in the charge. As charge forms a close circuit (secondary) heavy current flows through charge this current is responsible to produce heat in charge due to I2R losses. This heat is utilized to melt the charge. Where, R = Resistance of charge & I secondary current