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What is skin effect and proximity effect in electrical power system?

Skin Effect and Proximity effect are related to electrical terms Current and Current Density. In Conductors Skin Effect and Proximity Effects are present due Electromagnetism produced by Alternating Current flowing from it.
Skin Effect and Proximity Effect are the important term in power system. They are considered at the time of designing of Conductor of Power Transmission Line.

Skin Effect

Suppose there Conductors from which Alternating Current is flowing. Now what happens is due internal flux linkages Current density near the outer surface area is higher and it is gradually decreases toward the axis of the conductor.
This Non-uniform current density causes higher current flows near the surface of the conductor than the core for Alternating current. This Effect is Called “Skin Effect”.
Skin Effect becomes higher as the Frequency increases. Also due to skin effect DC resistance of the conductor becomes higher.
Skin Effect is absent in Direct Current (DC).

Proximity Effect

Current density in Conductor depends on internal magnetic flux distribution. Proximity means adjacency. So, Proximity effect present at when two Alternating current carrying conductors are near to each other.
Now what happens is Magnetic flux produced by both conductors” A & B” links with each other. That will change internal magnetic flux distribution such that for a conductor “A” current density near to the conductor “B” decreases and on the other side Increases. So, current in Conductor “A” will be less on Conductor “B” side and less on other side.
This Effect is called “Proximity Effect” in Power System. Proximity Effect will also increase effective Resistance of Conductor when Alternating current flows from it.

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