A 50 Hz, 50 MVA, 13.2 kV star grounded alternator is connected to a line through...

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A 50 Hz, 50 MVA, 13.2 kV star grounded alternator is connected to a line through a delta-star transformer as shown in Fig.11. The positive-sequence, negative-sequence and zero-sequence impedance of the alternator are j0.1 p.u, j0.1 p.u and j0.05 p.u, respectively. The transformer rated at 13.2 kV (delta) / 120 kV (star), 50 MVA with star solidly grounded has the sequence impedances of X₁ = X₂ = Xo =j0.1 p.u. each. The line impedances between Q and R are: 3X₁ = 3X₂ = Xo = j0.09 p.u. Find the fault current (in kA) for a double line-to-ground fault at point R (shown in Fig. 11). BIE a. 0.72 0.73 b. 2.15-2.16 c. 0.39 0.40 d. 1.181.19 Fig.11 IR XX A 50 Hz, 50 MVA, 13.2 kV star grounded alternator is connected to a line through a delta-star transformer as shown in Fig.11. The positive-sequence, negative-sequence and zero-sequence impedance of the alternator are j0.1 p.u, j0.1 p.u and j0.05 p.u, respectively. The transformer rated at 13.2 kV (delta) / 120 kV (star), 50 MVA with star solidly grounded has the sequence impedances of X₁ = X₂ = Xo =j0.1 p.u. each. The line impedances between Q and R are: 3X₁ = 3X₂ = Xo = j0.09 p.u. Find the fault current (in kA) for a double line-to-ground fault at point R (shown in Fig. 11). BIE a. 0.72 0.73 b. 2.15-2.16 c. 0.39 0.40 d. 1.181.19 Fig.11 IR XX