Simulation for a transmission loop using PowerWorld
I think you may be mistaking x^0 for x" - your document quality is poor so I'm doing my best to decipher. x" is probably a shortened version of x"d which is "generator direct axis subtransient reactance". x0 on the other hand is "generator zero sequence reactance". x2 is "generator negative sequence reactance".

Here is a paper that deals in how to calculate them. I don't know if this helps work out numbers to plug into your program but it might be a step on the way Here is another paper that is informative about the wonderful world of power generation and generator impedances.