The efficiency of a 20 kVA 15.4 / 0.4 kV three-phase power transformer is 73% for a load with unity power factor at rated power. Relative short circuit voltage% Uk = 30.0 and relative no-load current% I0 = 30. Since transformer (star-delta) is connected; 1-) Draw the primary reduced equivalent circuit and find its parameters. 2-) What is the power value measured in the short circuit test of this transformer? 3-) What is the iron loss value of this transformer?

The efficiency of a 20 kVA 15.4 / 0.4 kV three-phase power transformer is 73% for a load with unity power factor at rated power. Relative short circuit voltage% Uk = 30.0 and relative no-load current% I0 = 30. Since transformer (star-delta) is connected; 1-) Draw the primary reduced equivalent circuit and find its parameters. 2-) What is the power value measured in the short circuit test of this transformer? 3-) What is the iron loss value of this transformer?

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

Chapter8: Symmetrical Components

Section: Chapter Questions

Problem 8.39P

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