Fault current in YN/Yn0 transformer
Fault current in YN/Yn0 transformer
(OP)
Could any please confirm or contradict my understanding regarding distribution of fault current between hv and lv winding of a YN (ungrounded)/YN(grounded) transformer for phase to ground fault on lv side.As permy understanding the fault current distribution on hv side will be 1:1:2 ratio for phase to ground to fault on lv side






RE: Fault current in YN/Yn0 transformer
GE's Why's of Wyes
https://www.google.com/url?url=http://files.engine...
RE: Fault current in YN/Yn0 transformer
I think this thread is the same as what you are asking.
http://www.eng-tips.com/viewthread.cfm?qid=184543
RE: Fault current in YN/Yn0 transformer
RE: Fault current in YN/Yn0 transformer
The short answer is: virtually no fault current will flow, unless the transformer is a three-limb core form type, in which case the phantom delta effect means that some current will flow. The fault current in the phantom delta case shouldn't be as much as it would be if you had a Grd-Y/Grd-Y or Delta/Grd-Y connection.
Cheers,
mgtrp
RE: Fault current in YN/Yn0 transformer
There must be a complete path for the current to flow.
Ignoring exciting current, if current is flowing in a secondary winding there must be a corresponding (opposing) current flowing in the primary winding.