Transposition of transmission line

[eejacky]

Does any expert remember how to prove transposition of three equal length transmission line can minimise the mutual inductance and capacitance?

Thank you!!

 

[nihar]

Dear eejacky,
Kindly forward if any answers come to you on archunihar@rediffmail.com

Best Regards,
Nihar

 

[SMB1]

Actually the equation is too long to write, but please refer to (Electrical Transmission and Distrubution reference book) by Westinghouse, chapter 3 page 40.

Regards,

 

[jbartos]

Suggestion: Visit

http://www.ipst.org/TechPapers/2001/IPST01Paper107.pdf

http://www.selinc.com/techpprs/6090.pdf

http://eent1.tamu.edu/elen459/documents/Transmission_Line_Parameter_Calculation.pdf

etc. for more info

 

[GusD]

Hello eejacky

Sorry i don't know of any formula for this problem,but I do have a method that we have used quite successefully in our plant.
These are mostly long runs of 25KV or 5Kv trailing cables that power our major equipment.Due to the fluctuating loads, Voltages were being induced into the Trailing cable ground Monitoring circuits ,causing control relays to drop out and trip main switchouses.
In the long cable runs we have Junction Boxes and this allows us to "transpose" the phase cables at each JBox.
We identify the JBoxes cable entry and exits with "LINE" and "LOAD" signs and follow a transposition pattern as followsEg On the line side,left to right RED/BLACK/BLUE or A/B/C, on the load side BLACK/BLUE/RED or B/C/A.
We follow the same pattern for every other JBOx.
If you have to change the rotation,it would have to be done at the main Switch house.
I don't know if it applies to your system,it does work well for us.

GusD