Electric machinery fundamentals
5th Edition
ISBN: 9780073529547
Author: Chapman, Stephen J.
Publisher: MCGRAW-HILL HIGHER EDUCATION
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Textbook Question
Chapter 2, Problem 2.20P
A 50-kVA, 20,000/480-V, 60-Hz, single-phase distribution transformer is tested with the following results:
- Find the per-unit equivalent circuit for this transformer at 60 Hz.
- What is the efficiency of the transformer at rated conditions and unity power factor? What is the voltage regulation at those conditions?
- What would the rating of this transformer be if it were operated on a 50-Hz power system?
- Sketch the equivalent circuit of this transformer referred to the primary side if it is operating at 50 Hz.
- What is the efficiency of the transformer at rated conditions on a 50-Hz power system, with unity power factor? What is the voltage regulation at those conditions?
- How does the efficiency of a transformer at rated conditions and 60 Hz compare to the same physical device running at 50 Hz?
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Chapter 2 Solutions
Electric machinery fundamentals
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