A transformer with rated power of 250 kVA and a secondary voltage of 230/400 V, 50...

A transformer with rated power of 250 kVA and a secondary voltage of 230/400 V, 50 Hz, delivers energy to the following loads:
- 1 three-phase engine of nominal power 30 kW, 93% efficiency and power factor 0.9
- 90 lightning systems of 250 W each, rated voltage 230 V, and cos(phi)=0.6 (i), connected in a balanced manner
Consider a direct sequence and a reference of voltages V1=V∠0º
Find:
a) The true, reactive and apparent power provided by the transformer
b) The effective value of the current in each load
c) The phasors of the line currents provided by the transformer
d) The equivalent single phase circuit of the load
e) The reactive power and capacity (in wye and delta configurations) of a battery of capacitors so that we obtain a global power factor of 0.95 (i)
f) The new apparent power provided by the transformer after correcting the power factor
g) The effective value of the line currents if the transformer works at a power factor of 0.7 (i) in a balanced manner
h) The effective value of the line currents if the transformer works at a power factor of 1 in a balanced manner

Expert Solution

Manojponduru answered 1 month ago

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