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Q10.a) Draw the complete phasor diagram of the transformer under no-load conditions. (6)

b) The following results were obtained on a 50 KVA transformer: open circuit test-primary voltage, 3300 V; secondary voltage, 415 V; primary power, 430 W. Short circuit test primary voltage, 124 V; primary current, 15.3 A; primary power, 525 W; secondary current full load value. Calculate: (10)

(i) The efficiencies at full load and at half load for 0.7 power factor

(ii) The Voltage regulations for power factor 0.7 (i) lagging, (ii) leading

(iii) The secondary terminal voltages corresponding to (i) and (ii)