1. A 200-kVA, 3-phase, 50-Hz transformer has a voltage ratio (line voltages) of 33/11-kV and is delta/delta connected. The resistances per phase are: high voltage 30 , low voltage 0.88 Q and the iron loss is 2000 W. Calculate the maximum efficiency and the efficiency at 75 kVA loading, both at 0.75 power factor lagging.

1. A 200-kVA, 3-phase, 50-Hz transformer has a voltage ratio (line voltages) of 33/11-kV and is delta/delta connected. The resistances per phase are: high voltage 30 , low voltage 0.88 Q and the iron loss is 2000 W. Calculate the maximum efficiency and the efficiency at 75 kVA loading, both at 0.75 power factor 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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