Electromagnetic Induction Heating (EMIH )
The basic of induction heating equipment is electromagnetic induction.Electromagnetic Induction uses a primary magnetic field which induces an electrical current in the earth.Current is caused to flow in the circuit to which the coil is attached. If the magnet is withdrawn, the direction of the current is reversed. Such currents are called INDUCED CURRENTS. The current flows in the conductor as a result of an electromotive force that is induced - the so-called INDUCED EMF, which is often given the symbol ε.
The size of the current depends on how fast the magnet moves in or out of the coil, and the number of loops in the coil.
The phenomenon of inducing a current by changing the magnetic field in a coil of wire is known as ELECTROMAGNETIC INDUCTION.
This phenomenon underpins the design of all electric generators.
Electromagnetic induction takes place whenever the magnetic field in the vicinity of a circuit changes - this can happen when -
A magnet moves near a coil;
A coil moves near a magnet;
The current in a neighbouring coil changes;