Skin Effect

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Skin Effect:

If DC is passed in a conductor, the current density is uniform over the cross section of the conductor but when alternating current flows through a conductor, the distribution tends to become non uniform. There is a tendency of the current to crowd near the surface of the conductor. This is called skin Effect.

The current density is maximum at the surface of the conductor and minimum at the center of the conductor. The effect is equivalent to a reduction of the cross-section area of the conductor and, therefore the effective resistance of the conductor is increased.

Skin effect is caused by opposing eddy currents induced by the changing magnetic field resulting from the alternating current.

Fig. Skin Effect

Skin Effect increases with increase in

 i.) frequency

ii.) Diameter of Conductor

iii.) Permeability

Method to Reduce Skin Effect:

I.) Always use high conducting material such as copper, almunium etc.

II.) We should use stranded wire instead of solid wire.

III.) Frequency should be minimum during transmission.

IV.)  Diameter of Conductor should be less.

The main disadvantages of skin Effect are: skin Effect increases the Resistance in conductor results in power loss in transmission.



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