EHV Cables and OHL Modeling Assumptions

[lionheart333]

Dear Madams/ Sirs,

I am a fresh graduate power engineering engineer recently hired as a transmission planning engineer. Actually I am in charge of maintaining the system modeling and database in my utility. Particularly, I want to ask if there are any guidelines or practically valid assumptions of Positive / Negative and Zero sequences modeling of EHV cables and OHLs for different voltage levels. Kindly, could anybody give me a useful link that may be useful for me to identify the reasonable ranges of (Ro/R+) and (Xo/X+) of the EHV cables and OHLs modeling.

 

[davidbeach]

Overhead lines are vastly easier to deal with than cables. faq238-1287 contains several good references for calculating line impedances; Anderson's Analysis of Faulted Power Systems probably goes into the most detail. For cables your probably best off with software intended for that purpose or getting impedance calculations from the manufacturer for specific configurations. Part of the difficulty of calculating the impedance of cables is that you have to know all of the electrical properties of all of the layers of the cable.

 

[Marmite]

Chapter 5 of the Areva NPAG has some useful typical data.
Regards
Marmite

 

[lionheart333]

Thank you Guys. I really appreciate your kindness