A three phase transformer of 200MVA, 33kV/380kV, Yd11 is delivering nominal power at cosφ = 1....

A three phase transformer of 200MVA, 33kV/380kV, Yd11 is delivering nominal power at cosφ = 1.

Calculate the nominal primary and secondary line current.
Calculate the winding ratio n of this transformer.

The primary line current is 15,9A during an open circuit test. The measured power per phase is then 53kW. During a short circuit test (at nominal current), 271V primary line voltage is measured at cosφ = 0,225.

Calculate the total iron losses and total copper losses of this transformer.
Calculate the total iron losses if the transformer would be connected to 16,5kV (primary side).
Draw the single-phase equivalent circuit of this transformer. Give also the phase quantities of the voltages and currents and indicate what the circuit elements represent.

Please show process and computations with comments.

Expert Solution

Manojponduru answered 2 years ago

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