Texts:
A 3-phase, 3-winding, 1.5 MVA, 50 Hz transformer is required to meet the following specifications:
Primary: 66 kV (line), star connected.
Secondary: 6.6 kV (line), delta connected.
Tertiary: 440 V (line), star connected.
The maximum flux is not to exceed 0.1 Wb.
(i) Determine the required number of turns per phase on each winding.
(ii) Taking the magnetizing current as 5% of the rated current and the iron loss as 15 kW total, determine the input current, power factor, MVA, and MW when the secondary is loaded at 1.2 MVA, 0.9 p.f. lagging, and the tertiary is loaded at 300 kVA, 0.8 p.f. lagging.