A 500-kVA, 3-phase, 50 Hz transformer has a voltage ratio (line voltages) of 33/11 kV and isdelta/star connected. The resistances per phase are: high voltage 35 02, low voltage 0.876 22 andthe iron loss is 3050 W. Calculate the value of efficiency at full-load and one-half of full-loadrespectively (a) at unity pf and (b) 0.8 pf

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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 2 and the iron loss is 3050 W. Calculate the value of efficiency at full-load and one-half of full-load respectively (a) at unity pf and (b) 0.8 pf

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 2 and the iron loss is 3050 W. Calculate the value of efficiency at full-load and one-half of full-load respectively (a) at unity pf and (b) 0.8 pf

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 3.9P

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