4. Obtain the equivalent circuit of a 200/400V 50 Hz single phase transformer from the following test data. O.C.test: 1100V, 0.5A, 55W on primary Side, secondary being open circuited S.C. test: 10V, 80A, 400 W on LV side, high voltage side being short circuited. Calculate the voltage regulation and efficiency for the above transformer when supplying 100A at 0.8 p.f. lagging.

4. Obtain the equivalent circuit of a 200/400V 50 Hz single phase transformer from the following test data. O.C.test: 1100V, 0.5A, 55W on primary Side, secondary being open circuited S.C. test: 10V, 80A, 400 W on LV side, high voltage side being short circuited. Calculate the voltage regulation and efficiency for the above transformer when supplying 100A at 0.8 p.f. lagging.

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter3: Power Transformers

Section: Chapter Questions

Problem 3.26MCQ: In per-unit equivalent circuits of practical three-phase transformers, under balanced thr-phase...

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For an ideal transformer, the efficiency is (a) 0 (b) 100 (c) 50
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For an ideal 2-winding transformer, an impedance Z2 connected across winding 2 (secondary) is referred to winding 1 (primary) by multiplying Z2 by (a) The turns ratio (N1/N2) (b) The square of the turns ratio (N1/N2)2 (c) The cubed turns ratio (N1/N2)3
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