Question

# Please do study question 4.18 4.18: For the transformer of Problem 4.15, draw approximate equivalent circuits...

4.18: For the transformer of Problem 4.15, draw approximate equivalent circuits
as viewed from (a) the primary side and (b) the secondary side. In each
case, determine (a) the efficiency and (b) the regulation if the load has a
lagging power factor of 0.8.

4.15: A 230-kVA, 2300/230-V, 60-Hz, step-down, two-winding transformer has
the following parameters R(H), = 1.2 ohms, X(H), = 3ohms, R(L), = 12 mohms, X(L) , = 30 mohms,
R(CH), = 2 kohms, X(MH), = 1.8 kohms. If the transformer operates at half load at its
rated terminal voltage with a unity power factor, what is its efficiency?

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