Proximity of bundled conductors in overhead transmission system in terms of ampacity? 1

[JTailor]

can anyone guide me on how to capture proximity effect of bundled conductor spacing on ampacity calculations of an overhead AC line? I am aware of IEEE 738-2006 but cannot find anything on bundled conductor proximity effect.

 

[bacon4life]

A while back copper.org had calculations methodologies for calculating proximity effects of various busbar configurations. Unfortunately the have reorganized the site so my bookmarks no longer works. Even though your conductors probably are not copper the same physics applies to both materals.

 

[7anoter4]

Since the distance between different conductors it is more than conductor diameter the proximity effect is negligible. See:
Aluminum Electrical Conductor Handbook chapter 3 Engineering Design
Proximity Effect:
“When two conductors are spaced relatively close to one another and carry alternating current, their mutual inductance affects the current distribution in each conductor. However, if the distance apart of the conductors exceeds ten times the diameter of a conductor the extra I'R loss caused by this crowding is less than 1 percent, hence ordinarily can be neglected.”
For 3 single core cable IEC 60287-1-1 /2.1.4 Proximity effect factor yp for three-core cables and for three single-core cables- may be used in the case of transmission overhead line too.