Consider a 25-kVA, 400/1600 V single-phase transformer supplying full-load current at 0.85 lagging power factor. The O.C./S.C. test results are as follows: O.C. test: 400 V, 1.5 A, 470 W (L.V. side) S.C. test: 35 V, 18 A, 620 W (H.V. side) Find: (i) The parameters of the transformer, (ii) The full-load efficiency. (iii) The maximum efficiency. (iv) The efficiency at 50% of full-load and p.f. 0.75 lagging.

Consider a 25-kVA, 400/1600 V single-phase transformer supplying full-load current at 0.85 lagging power factor. The O.C./S.C. test results are as follows: O.C. test: 400 V, 1.5 A, 470 W (L.V. side) S.C. test: 35 V, 18 A, 620 W (H.V. side) Find: (i) The parameters of the transformer, (ii) The full-load efficiency. (iii) The maximum efficiency. (iv) The efficiency at 50% of full-load and p.f. 0.75 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 3.57P: A two-winding single-phase transformer rated 60kVA,240/1200V,60Hz, has an efficiency of 0.96 when...

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