Transmission Line Voltage Level and MVA Capacity

DO YOU MEAN TRANSMISSION LINE VOLTAGE LEVEL & MVA CAPACITY ?

nascon

YES.

Quote "how to find what Kva line is running by visual inspection"

You can't. You must know the conductor ampacity and the voltage. Unless you are the utility employee you would know know this information. Suggest you contact the utility and ask them to provide the details.

Hi,

But we can find the Transmission Line Volatge by counting the number of discs in the string or suspension insululator. Is't It?

Regards,

Kailash

That is a crude way but yes, however insulator construction varies and so do the number of disks (or rain sheds).

Approximate maximum current capacity of a line can be estimated if you know the line type (all aluminium, aluminium with steel core, copper, etc) and its cross sectional are, but this is hardly practical.

VOLTAGE 66 KV 132 KV 220 KV 400 KV

INSULATORS

SUSPENSION 5 9 15 23

70/90 KN 70/90 KN 70/90 KN 120 KN

TENSION 6 10 16 24

90/120 KN 90/120 KN 90/120 KN 120/160 KN

THIS WILL GIVE YOU IDEA ABOUT THE TRANSMISSION LINE VOLTAGE LEVEL.

REGARDING MVA :- (MW/P.F) DEPENDNS ON TYPE OF CONDUCTOR USED :-

AMBIENT TEMP 45 DEG C AND CONDUCTOR TEMP 75 DEG C

ACSR CONDUCTOR RATING IN MW

SINGLE PANTHOR :- 66 KV 33.6 MW AT@ 0.80 P.F.

35.7 MW AT @ 0.85 P.F

SINGLE MOOSE :- 220 KV 182 MW AT@ 0.80 P.F.

193 MW AT @ 0.85 P.F

TWIN MOOSE :- 400 KV 659.2 MW AT@ 0.80 P.F.

700.4 MW AT @ 0.85 P.F

TWIN BERSIMIS :- 400 KV 772.8 MW AT@ 0.80 P.F.

821.8 MW AT @ 0.85 P.F

nascon

Do not shout at us.

My experience is that the number of disc insulators, or rain skirts, vary depending on type of material used to make the insulators and the atmosphere that they are installed in. In the SE United States you will see 130 KV with 9 skirts/discs and 7 in the more arid SW. In one industrial area we had a 130 KV line with 11 skirts/discs due to the heavy air pollution, ditto for coastal lines where salt contamination was a problem. The best way to tell what you have in the field is to find a transformer data plate and read it. When you start making assumptions you have taken the first step towards screwing something up.

What is the loading capacity of 132 kV Zebra, 132kV Moose, 220kV Zebra, 220kV Moose transmission line? ? ?

Abient temp 45 degree and conductor temp 75 degree c., Zebra rated as 546 Amp., and Moose as 595 Amp., Bergimis as 697 Amp.

The number of insulators is applicable to the voltage, ie KV in KVA.

The A is the conductor diameter, which is also controlled by KV as too small a conductor diameter will be in corona all the time. There are basicly two types of conductors aluminum wrapped over a steel strength cable and aluminum wrapped over a composite strength cable. The new composite conductors can carry twice as much A as the steel core for the same diameter conductor.

The construction of the conductor, takes a keen eye, as there are also conductor bundles with multiple conductors and spacers between them as KV and A increase.

I hope there are no more questions as I have no more simple answers.