750MW 120hz Excitor/Alternator Diff

[TheEasty]

This is my 1st experience with a 120hz excitor. The original system has an 87 surrounding just the excitor wdgs GE CFD12 configured for 120hz. We are looking at a digital relay upgrade.

Can anyone give me some wisdom on this 120hz excitor and diff protection scheme?

I never seen a diff on an excitor. Unsually it’s a stator/rotor gnd protection scheme.

Thank you
The Easty

 

[edison123]

You cannot have a differential protection on a rotating brushless exciter armature, which are normally at higher frequency of 120 to 240 Hz for a lesser ripple content in DC output.

Muthu

http://www.edison.co.in