A 20-kVA 8000/480-V distribution transformer has the following resistances and reactances: R, = 32N R =0.05 2 X, = 45N X =0.06 Q %3D R. = 250 kN XM = 30 k2 The excitation branch impedances are given referred to the high-voltage side of the transformer. (a) Find the equivalent circuit of this transformer referred to the high-voltage side. (b) Find the per-unit equivalent circuit of this transformer. (c) Assume that this transformer is supplying rated load at 480 V and 0.8 PF lagging. What is this transformer’s input voltage? What is its voltage regulation?

A 20-kVA 8000/480-V distribution transformer has the following resistances and reactances: R, = 32N R =0.05 2 X, = 45N X =0.06 Q %3D R. = 250 kN XM = 30 k2 The excitation branch impedances are given referred to the high-voltage side of the transformer. (a) Find the equivalent circuit of this transformer referred to the high-voltage side. (b) Find the per-unit equivalent circuit of this transformer. (c) Assume that this transformer is supplying rated load at 480 V and 0.8 PF lagging. What is this transformer’s input voltage? What is its voltage regulation?

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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