SKM Generator Tab Information help

[samir]

Hello,

I am filling up the generator tab in SKM from the alternator data sheet (attached).

1.What should be entered for subtransient reactance for positive, negative and zero?

2.How to calculate the Ra in pu on machine base? Is it just to find base impedance and divide the Ohms with it.

3.Also need help in plotting the decrement curve. Can someone direct me to link or thread with example explained on how plot the same on SKM?

Thank you in advance

 

[jusme123]

http://www.cumminspower.com/www/literature/technicalpapers/PT-6008-GeneratorReactances-en.pdf

 

[samir]

http://www.cumminspower.com/www/literature/technicalpapers/PT-6008-GeneratorReactances-en.pdf

I did refer to this document earlier but does not infer on what is the positive, negative and zero sub-transient reactance.

Also need some advise or literature to refer for decrement curve.