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Large Transformer Inrush

Large Transformer Inrush

Large Transformer Inrush

(OP)
IS there a way to calculate the inrush current manually?  I have had this 34.5kV delta:12.47kV wye transformer tested and obtained the following test data:
winding resistance between taps
turns ratio test
dar/polorization index

Would an open circuit test give me the required values?
I am buying the EMTP software, so what should I have my EC test?

The manufacturer is not helping at this time and I cannot energize my line until I can prove to the utility I want trip there recloser.

RE: Large Transformer Inrush

(OP)
The no load watt losses at 85 are 7913
Load losses (watts) at 85 are 22124
Target impedance 5.55%+-6.3%
Efficiency at 50% load is 99.417

RE: Large Transformer Inrush

To have a first estimate of inrush current amplitude you should know the air-core (or saturated) inductance of energized winding, the nominal and saturation flux density of the core. The formula can be find  for instance in:
G. Bertagnolli, "Short circuit duty of power transformers" ABB. or in: http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=5607995
I report the formula in the attached jpg.
  

Si duri puer ingeni videtur,
preconem facias vel architectum.

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