Unique Delta-Wye Transformer Fault

Thread Starter

garrettb11

Joined Feb 1, 2021
2
I am trying to determine what the secondary voltages would be after the following fault occurred. Basically one phase energized two bushings on a delta-wye transformer.

1612199830781.png

I believe it would be something like this but I am not entirely sure.

1612199908694.png
 

Thread Starter

garrettb11

Joined Feb 1, 2021
2
Phasors.... is this homework?
No, I work for a power company and had a fault occur a few weeks back that we couldn't quite figure out. The fault occurred on the high side of the transformer but our metering data only displays voltage magnitudes on the low side (no angles). The low side voltage magnitudes in the image are what we gathered and we think this type of fault may have caused it. Just wanted to see if anyone agreed or not.
 

Marley

Joined Apr 4, 2016
502
Surely a short across a winding like that would immediately trip circuit breakers? As it's a star/delta, probably on all three phases. Otherwise I expect some serious heat generation!
 
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