Question

Can someone solve this with some notes explaning why is that so? When should we use a and when should we use a' in the calculation

b) Three sets of single-phase transformers each of rating 60 kVA, 1100/254 V, 50 Hz are connected to form a three-phase, 1100/440 V, transformer bank. The equivalent impedance of each transformer referred to low voltage side is (0.04 + j 0.16) ?. The three-phase transformer bank supplies a load of 150 kVA at a power factor f 0.8 lagging by means of a common three-phase feeder whose impedance is (0.008 + 10.04) ? per phase. The line voltage across the load is 440 V. ) Draw the schematic diagram showing the transformer connection ) Determine the single-phase equivalent circuit referred to the low voltage side. i) Determine the transformer winding currents (the phase currents) and the line currents. iv) Determine the sending end line voltage and voltage regulation (9 marks)

Answer 1