I would appreciate any help with this question:
A 100kVA transformer has 400 turns on the primary and 80 turns on the secondary. The primary
and secondary resistances are 0.3ohms and 0.01ohm respectively, and the corresponding leakage
reactances are 1.1ohms and 0.035ohm respectively. The supply voltage is 2.2kV. Calculate equivalent
impedance of the transformer referred to the primary side, and the magnitude of the secondary
terminal voltage for full load having a power factor of 0.8 lagging. Repeat this for full load with a
power factor of 0.8 leading. Assume as an approximation that the power factors seen on the
primary and secondary side of the transformer are the same and Sin=Sload
I can get the first part which is the equivalent impedance of 2.05 ohms angle
77.4 degrees.
But the next part the answer should be 425V and 447.2V
I tried working out the primary which is 100KVA/2.2KV = 45.45 A
hen using the turns ratio Is = 227.25
hence on the secondary side it is 100KVA/227.25 = 440V
A 100kVA transformer has 400 turns on the primary and 80 turns on the secondary. The primary
and secondary resistances are 0.3ohms and 0.01ohm respectively, and the corresponding leakage
reactances are 1.1ohms and 0.035ohm respectively. The supply voltage is 2.2kV. Calculate equivalent
impedance of the transformer referred to the primary side, and the magnitude of the secondary
terminal voltage for full load having a power factor of 0.8 lagging. Repeat this for full load with a
power factor of 0.8 leading. Assume as an approximation that the power factors seen on the
primary and secondary side of the transformer are the same and Sin=Sload
I can get the first part which is the equivalent impedance of 2.05 ohms angle
77.4 degrees.
But the next part the answer should be 425V and 447.2V
I tried working out the primary which is 100KVA/2.2KV = 45.45 A
hen using the turns ratio Is = 227.25
hence on the secondary side it is 100KVA/227.25 = 440V