Line reactance and voltage level

[electrics]

At transmission lines how a relationship can be made about the voltage level and the reactance?

 

[Hameedulla-Ekhlas]

I know two ways voltage and reactance.

1. You can find voltage and reactance relationship in cable catalog and appropriate voltage drop and ampere capacity calculation and consideration.


2. You can find voltage and reactance relationship through calculation

Suppose you know the voltage and you want to find line reactance for selecting a cable according to reactance. In this case, you can select transposed line and distance between conductors.

Through this formula you can find

L = 2*10^-7ln(Deq/Ds)
X = 2*3.14*f*l km/ph

there are many methods hope others will explain more clearly for you.

 

[Hameedulla-Ekhlas]

after finding the reactance , you can find the ampere capacity of line and voltage level.

 

[electrics]

i mean it decreases or increases with voltage increasing?

 

[Hameedulla-Ekhlas]

Mmmmmm, I got what you mean.

to increase voltage level ofcourse current decreases and since current decreases you can select small size of conductor

Indeed, reactance depends on cable size larger cable smaller reactance and resistance. Smaller cable larger reactance and resistance.

So, when you decrease voltage, current increases and you have to select larger cable size. Larger cable size has smaller reactance.