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3. Two (2) generators are connected to the low voltage bus of a station feeding into a three phase 13.8kV delta to 69kV wye transformer as illustrated in the single line diagram below LV Bus 50MVA Xd"=0,25 25MVA Xd" = 0.25 G₁ G₂ 13.8kV Ti A3 EY 75MVA X = 10% Total Value Question 3: (a) 5 marks (b) 8 marks 69kV Transformer T, is initially unloaded, and there is no circulating current between the machines. At the instant a fault occurs, the voltage on the high tension side of transformer T, is 66kV (a) Draw and label the correct system reactance diagram on a base of 69kV and 75MVA in the high tension circuit. (b) Calculate the magnitude of the subtransient short circuit current in per unit at point of fault when a three phase symmetrical short circuit occurs on the high voltage terminals of transformer T₁.