Three single-phase 100-kVA, 2400:240-V, 60-Hz transformers (each of which has an equivalent series impedance of 0.045+j0.16 Ω referred to its low-voltage side) are connected to form a three phase, 4160:240-V transformer bank, which in turn is connected to a three-phase feeder with an impedance of 0.5 + j1.5 Ω/phase. When the three-phase transformer bank delivers 250 kW at 240 V and 0.866 lagging power factor, determine:
(a) The transformer winding currents.
(b) The sending-end voltage (line to line) at the source.