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