Power Transformer Capacitance?

[JMFenton]

Can anybody tell me what to expect for values of coupling capacitance between the windings and between the windings and core of power transformers. I'm particularly interested in 3 ph transformers rated at between 7 MVA and 100 MVA, with primary voltage of 72 kV L-L. Any help will be greatly appreciated. Thanks.

 

[bobziva]

Why you want to know that ? Capacitance exists but reactance is much higher and nobody calculate transformer capacitance.

 

[JMFenton]

To bobziva
On high impedance grounding systems (and ungrounded systems) the capacitance of the transmission and sub-transmission lines as well as that of lightning arresters and transformers (of all types) the reference pathway is through capacitive coupling. It's this path that is of concern to me.

 

[jbartos]

Suggestion: The transformer winding capacitance to ground will vary according to BIL anywhere from 4 microfarads to 10 microfarads

 

[jbartos]

Suggestion: Reference:
1. IEEE Std 399-1997 IEEE Recommended Practice for Industrial and Commercial Power Systems Analysis, (Brown Book)
Figure 11-34 Typical values of transformer winding capacitance to ground

 

[JMFenton]

I wish to thank all that have responded. You have pointed me in the correct direction.