1. A 500-KVA, 3-phase, 50-Hz transformer has a voltage ratio (line voltages) of33/11-kV and is delta/star connected. The resistances per phase are: high voltage35 , low voltage 0.876 Q and the iron loss is 3050 W. Calculate the value ofefficiency at full-load and one-half of fullload respectively (a) at unity p.f. and (b)0.8 p.f.

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1. A 500-KVA, 3-phase, 50-Hz transformer has a voltage ratio (line voltages) of 33/11-kV and is delta/star connected. The resistances per phase are: high voltage 35 , low voltage 0.876 and the iron loss is 3050 W. Calculate the value of efficiency at full-load and one-half of fullload respectively (a) at unity p.f. and (b) 0.8 p.f.

1. A 500-KVA, 3-phase, 50-Hz transformer has a voltage ratio (line voltages) of 33/11-kV and is delta/star connected. The resistances per phase are: high voltage 35 , low voltage 0.876 and the iron loss is 3050 W. Calculate the value of efficiency at full-load and one-half of fullload respectively (a) at unity p.f. and (b) 0.8 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 3.4P: A single-phase 100-kVA,2400/240-volt,60-Hz distribution transformer is used as a step-down...

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