Transformer core loss 1

[Amri80]

I had a problem about core losses of a three phases transformer. I did test on a three phases transformer at no load condition for measuring its core losses, it didn't show the same result when measuring at Y or Delta or Z connection of the windings. I hope some of you can help me about this problem. Thanks before.

 

[dpc]

How are you making the measurements? For highly accurate results you may need to compensate for the harmonics present in the exciting current. Also, any source voltage flucuations can degrade measurement accuracy.

 

[busbar]

§8 in IEEE Std C57.12.90 (1993) is typical boilerplate for loss tests. Has that been reviewed?