Distribution Substation - Clearances

[johnaeus]

Hello,

I am a beginner and I have to conceive a little distribution substation for the rural electrification, 10MVA, 110/10kV. We are going to tap the 110 kV line.
How can I find the air clearances beetwen the lines / equipment.
Could you recommend me something: Internet sites, IEEE, ANSI, IEC standards / norms ?

Are there any Internet sites where I can learn more about rural electrification methods and distribution substations.

Many Thanks,

Johnaeus

 

[davidbeach]

The USDA has a good substation guide for rural electrification, it has been mentioned several times in this forum, a search should turn it up quickly, try searching for "substation design". You will also need a copy of the NESC (National Electrical Safety Code).

 

[RalphChristie]

David is correct, the USDA guide (Bulletin 1724E-300, Design Guide for Rural Substations) is a very helpful reference. You can download it at:

http://www.usda.gov/rus/electric/pubs/1724e300/1724e300.pdf

(It is a rather big file - 10MB)

check also:

http://www.eng.uwi.tt/depts/elec/staff/alvin/ee35t/notes/Substation-Design.html

Just one thing to add:
It depends on where you are located to determine which standards to use. Standards from other regions might be helpful references, but may not necessarily be used in your country.

 

[stevenal]

http://www.nema.org/redirect/redirectfile.cfm?id=6281&filename=/stdssg6.pdf

See table 36-2 on page 13.

 

[Xuewei]

What does IEC say about the clearance?

 

[johnaeus]

Thanks guys,

You are extraordinary. I have downloaded your suggested links and the documents are very interesting (especially the the USDA guide-Bulletin 1724E-300, Design Guide for Rural Substations).

Best,

Johnaeus

 

[cuky2000]

For clearance comparison purposes, here is sometime to start.

The ANSI clearances are slightly more conservative than the one published by IEC. Both standards base the clearances in the BIL for HV = 220 & 230 kV and for higher voltages the clearances are based in the switching surge levels.