6) In a 3-phase power as shown in the following figure, voltages of both the generators A and B are1.020° in per unit. The impedances of the first generator (A) are X1 = j0.3, X2 = j0.2, and Xo = jo.05,all in per-unit. Similarly, the impedances of the second generator (B) are X1 = j0.25, X2 = j0.15, and Xo = j0.03, all in per-unit. Impedances of the first transformer (TR1) are X1 = X2 = Xo = j0.12 and impedances of the second transformer (TR2) are X1 = X2 = Xo = j0.10. Positive, negative and zero sequence impedances of both lines are X1 = X2 = 0.3 an Xo = j0.7 in per unit, respectively.If a double line to ground fault occurs at point F (assume the voltage at the point F before the fault 0is 1.020° in per unit); (a) Find the sequence networks and equivalent impedances. (b) Combine the equivalent circuits according to the connections of a double line to ground fault. (c) Find the per-unit value of fault current If.

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