State and explain the losses in transmission line.

1 Answer

Losses in Transmission Line:- There are three ways in which energy, applied to a transmission may desperate before reaching the load. They are

1) Radiation Losses:-  Its occurs when a transmission line may act as an antenna when the separation of the conductor is an appreciable fraction of a wave length . This loss increase with frequency for any given transmission line eventually ending that lines usefulness at some high frequency.  This loss is more in parallel wire lines than to coaxial lines. 

2) Conductor Or I2 R loss:-

 This loss is proportional to the current and their fore inversely proportional to characteristics impedance

 It also increases with frequency, this time because of the skin effect.

3) Dielectric loss:

 This loss is proportional to the voltage across the dielectric and hence inversely proportional to the characteristic impedance for any power transmitted.

 It again increases with frequency because a gradually worsening properties with increasing frequency for any given dielectric medium.

4) Corona Effect:-

 Corona is a luminance discharge that occurs between the two conductors of a transmission line when the difference of proportional between them exceeds the break down voltage of the dielectric insulator.

 Generally when corona occurs, the transmission line is destroyed.
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