(Solved): 3. Two generators are connected in parallel to the low-voltage side of a three-phase Y transfo ...

3. Two generators are connected in parallel to the low-voltage side of a three-phase $??Y$ transformer, as shown in the figure below. Generator 1 is rated 50,000 kVA, 13.8kV. Generator 2 is rated 25,000kVA, $13.8\mathrm{kV}$. Each generator has a sub transient reactance of $25\%$ on its own base. The transformer is rated $75,000\mathrm{kVA},13.8?/69\mathrm{Y}\mathrm{kV}$, with a reactance of $10\%$ on its own base. Before the fault occurs, the voltage on the high-voltage side of the transformer is $66\mathrm{kV}$. The transformer is unloaded and there is no circulating current between the generators. Find the sub transient current in each generator when a three-phase short circuit occurs on the high-voltage side of the transformer. Hint: The circuit to analyze should appear as below.