Three singlephase transformers are to be connected as 3phase

Three single-phase transformers are to be connected as 3-phase transformer bank. The ratings of each transformer is 500 kVA, 2250/225 V. The ratings of the 3-phase transformer bank when connected as a step-up transformer as shown below are 1500 kVA 1.5 MVA 1500 kVA 1.5 MVA; 2250/225 V; 225/3900 V; 3900/390 V; 390/2250 V

Solution

S=3*s = 3*500 =1500 kVA

Voltage ratio is not changed.

Option A is correct.