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Z = 0.9 x 0.155 x sin(acos0.9) x 0.024 = 0.150 0.150 x 20 = 3 V 4 awg ~42,000 cmil

Do I get a cookie!?!   :)

~ 147.4 uF

 I think it works like this

Yepper sqrt[(20/sqrt3)^2 + 10^2] = 15.2753 sqrt(700/3) = 15.2753

No picture so I assume the fault is between the M and G. Looking bach into the system from the fault they are in parallel.

Zb = V^2 / S (single phase) x sqrt3 = 0.0399 or277/12028 = 0.023

2 WAG's P Max = 3 x Vs x Vr /  XL so if P load is constant raising V increases XL or does increasing V increase shunt C offsetting or 'lowering' apparent XL???

Lower V does not lower XL but raising V raises XL ?

Here's my take in summary the prim line/phase and sec phase to line offset/cancel.  The polarity offset is opposite or 180

Here's mine

I added the A and B individual contributions to A+B.  As you can see A (with B) is proportionally lowered from A alone. The Z 'seen' (sensed) is the same.

This may help.  Gen B does increase total  fault S (and reduces Gen A fault S) but the relay trips at same point.  Gen B will proportionally reduce A's fault Vdrop and I but the ratio (Z) should be ~ the same.  (Numbers are from my previous example).

Gen has 10 mva 'available' but it only supplies a portion of the fault's 3.75, 1/3 of it.. The fault is no different than any other 'load' and will be supplied by both gens. there may be a potential difference at  bus A but it will be equalized by i flow between the gens and load/i division

By inspection you can calc the fault since Z line >>> Z xfmr 277/2 or 480/(sqrt3 x 2) = 138

Sawtooth rms = 'AC' component = Peak/sqrt3 = 1.2/sqrt3 = 0.6928 DC rms = 0.75 Waveforms can be summed = sqrt(0.6928^2 + 0.75^2) = 1.02 if considered 'in phase' then 0.75 + 0.45 /sqrt3 = 1.0098

My take, won't be the first time I'm wrong (definitely not the last).  Using rough numbers And basic calcs for example

He is assuming the fault is a fixed Z. So the 'load' would be served by both G's.

Sym components are cool, but sometimes there are simpler methods. find Z base using 1 mva and 1 kv = 1 ohm and use pos seq values since pos=neg and convert PU values, consider we only need magnitude, no phase or Vdrop Gen Z = 0.15 Ohm and xfmr Z = 0.08 Ohm 2 lines x sum = 0.46 Ohm 1000 v /...

I get the same using PU or Imped or MVA