A25KVA, 2500/250V, transformer takes 3A and 150W when 250V is applied to L.V Winding and H.V winding is kept open. It takes 10 A and 350W when the L.V winding is short-circuit and 90 V is applied to H.V winding Find: i) Percentage regulation on full-load at 0.8 p.f. lagging ii) KVA supply at maximum efficiency iii) The maximum efficiency at unity p.f.

A25KVA, 2500/250V, transformer takes 3A and 150W when 250V is applied to L.V Winding and H.V winding is kept open. It takes 10 A and 350W when the L.V winding is short-circuit and 90 V is applied to H.V winding Find: i) Percentage regulation on full-load at 0.8 p.f. lagging ii) KVA supply at maximum efficiency iii) The maximum efficiency at unity p.f.

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 3.5MCQ: For an ideal 2-winding transformer, an impedance Z2 connected across winding 2 (secondary) is...

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For a short-circuit test on a 2-winding transformer, with one winding shorted, can you apply the rated voltage on the other winding? (a) Yes (b) No
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The efficiency of a transformer at load 0.8 p.f. Lag is -- at load 0.8 p.f. Lead * equal less than more than none of these