A 4.2-kVA, 366 / 126 -volt distribution transformer has the following equivalent resistance and leakage- reactance values referred to the primary: rep = 4.5 ohm; xep = 7.4 ohms. If this transformer is operating at 125% full-load with 0.63 power factor leading, what is its total copper losses in watts

A 4.2-kVA, 366 / 126 -volt distribution transformer has the following equivalent resistance and leakage- reactance values referred to the primary: rep = 4.5 ohm; xep = 7.4 ohms. If this transformer is operating at 125% full-load with 0.63 power factor leading, what is its total copper losses in watts

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 3.16P: A single-phase, 50-kVA,2400/240-V,60-Hz distribution transformer has the following parameters:...

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A single-phase, 50-kVA,2400/240-V,60-Hz distribution transformer has the following parameters: Resistance of the 2400-V winding: R1=0.75 Resistance of the 240-V winding: R2=0.0075 Leakage reactance of the 2400-V winding: X1=1.0 Leakage reactance of the 240-V winding: X2=0.01 Exciting admittance on the 240-V side =0.003j0.02S (a) Draw the equivalent circuit referred to the high-voltage side of the transformer. (b) Draw the equivalent circuit referred to the low-voltage side of the transformer. Show the numerical values of impedances on the equivalent circuits.
The ideal transformer windings are eliminated from the per-unit equivalent circuit of a transformer. (a) True (b) False
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