Short Circuit Testing

[Tinh123]

A field person asked me this question and I couldn't find the document to justify, so we need your help. Given a 3-phase transmission line with length (L)and all three phases are shorted, what is the 3-phase voltage need to apply in the other end to achieve an "X" Amp Line-Ground Current for each phase? If you have any link relates to the above subject would be great. Thank you.

 

[dpc]

If all three phases are shorted and you apply three-phase voltage, you have a three-phase fault and there is no line-to-ground current.

 

[DanDel]

This sounds like sequence impedance testing, where, if I remember correctly, the three phases are shorted to ground at one end, and the same voltage is applied between all three and ground at the other end. The current is measured and the impedance is calculated.

 

[JBinCA]

DanDel,

That would be a test to measure 3Io, right?

Thanks,

JB

 

[DanDel]

I think so. I remember reading the procedures for field testing both zero and positive sequence impedances, but can't remember the specifics.