Transformer inductance & resistance 1

[coconutalley]

Is there a rule of thumb as to figuring out what the inductance and resistance should be in a transformer for a given power rating [kVA or MVA], turns ratio, and may be voltages?

I heard there is this 5% or 10% rule. I am putting together a model but Manufacturers don't usually give you the specs on inductance and resistances.

 

[dpc]

There are recommended impedances in the ANSI standards for power transformers. The impedance is almost entirely inductive. Impedance is a function of the transformer voltage (BIL) and size (as a first approximation). It can vary quite a bit.

The IEEE Red Book has typical values of impedance and X/R for various types and sizes of transformers - that would be a good starting point.

But no, there is no one-size fits all method to estimate transformer impedance based only on the kVA rating.

Hope that helps.