Example 33.2. 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 p.f. and (b) 0.8 p.f. (Electrical Machinery, Madras Univ. 1985)

Example 33.2. 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 p.f. and (b) 0.8 p.f. (Electrical Machinery, Madras Univ. 1985)

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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Similar questions

Consider an ideal transformer with N1=3000andN2=1000 turns. Let winding 1 be connected to a source whose voltage is e1(t)=100(1| t |)volts for 1t1ande1(t)=0 for | t |1 second. A2- farad capacitor is connected across winding 2. Sketch e1(t),e2(t),i1(t),andi2(t) versus time t.
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