Neutral Grounding Reactor Size

I need help sizing a neutral grounding reactor so the Isc 3p=Isc SLG

Reactor sizing:

Isc SLG=3(E/1.73) / (x''d+x2+x0) and Isc 3p=(E/1.73)/x''d

3(E/1.73) / (x''d+x2+x0)= (E/1.73)/x''d

Add new reactance

3(E/1.73) / (x''d+x2+x0)+3xnew=(E/1.73)/x''d

The reason I chose 3xnew is for the sum of the single line to ground faults

Zbase=480V^2/3125kVA = .073

x''d .1194

x2=.1166

x0=.0081

Isc 3p= (480/1.73) / x''d = 2319/Zbase = 31780A

31780A=3(E/1.73) / [(x''d+x2+x0)+3xnew]

Convert from pu

31780A=3(480/1.73) / [(.018 ohms)+3xnew]

3xnew = .0084 therefore the new neutral grounding reactance for the generator is .0028 ohms

Thoughts…