A 240-kVA, 480/4800-V, step-up transformer has the following constants: Rs = 2.5 Ω, Xs = j5.75 Ω, Rp = 25 mΩ, Xp = j57.5 mΩ. The core-loss resistance and the magnetising reactance on the high-voltage side are 18 kΩ and j12 kΩ, respectively. The transformer is operating at 50% of its rated load. If the load is purely resistive, determine the percent power efficiency of the transformer

A 240-kVA, 480/4800-V, step-up transformer has the following constants: Rs = 2.5 Ω, Xs = j5.75 Ω, Rp = 25 mΩ, Xp = j57.5 mΩ. The core-loss resistance and the magnetising reactance on the high-voltage side are 18 kΩ and j12 kΩ, respectively. The transformer is operating at 50% of its rated load. If the load is purely resistive, determine the percent power efficiency of the 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

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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