- The induction heating works on the principle of transformer action.
- The transformer working principle is based on the Faraday’s law of electromagnetic induction. This transfers the electrical energy from primary side to the secondary side (circuit) of the transformer.
- The working principle of induction furnace is similar to the eddy current loss in transformer.
- This loss is dissipated in the form of heat in the transformer cores. If such a loss in the form of heat is utilized in heating of materials, then it will be useful to heat up the charge.
- When alternating current flows in a conductor, it produces reversing magnetic field.
- If any coil is placed in this reversing magnetic field, an emf will induce in it. Similar to the emf induced in the secondary of a transformer.
- This transfer of electric energy from primary winding to the secondary winding by electromagnetic induction is utilized to form the heat.
- The heat developed in the charge mainly depends on the following factors:
(i)The power drawn by the charge.
(il) Supply voltage and current
(iii) The resistance of the charge.
- The power depends upon the voltage, power frequency and the resistance of the charge, power
drawn is equal to V2/R
- Therefore, to develop sufficient amount of heat for one litre of the charge,
1)Resistance of the charge must be low which s possible only with metal.
2)Voltage must be higher which is obtained by employing higher flux and higher frequency
