Definition of Commutating and Through-Fault Impedance?

[jimbofitz]

I'm looking at a customer spec that asks for a specific Commutating Impedance and Through-fault Impedance. It is for a 12 pulse transformer-rectifier application. I think commutating impedance would be the leakage inductance and copper losses in the transformer. I would imagine through-fault impedance would be the same. They are asking for a 6.5% commutating and 4% through-fault impedance. I have no information about what is feeding me so I can't add any source impedance to the calculation if neccesary.

Any insight would be helpful.

Regards,
Jim

 

[7anoter4]

See:
Electric Power Engineering Handbook
By Leonard L. Grigsby, James H.
Para 5.4-5.8

http://books.google.com/books?id=_r...X&oi=book_result&resnum=3&ct=result#PPT120,M1

 

[jimbofitz]

Thank you 7anoter4.

That link was perfect.