Answered: A 200 kva transformer has an efficiency…

A 200 kva transformer has an efficiency of 98% at full load. If the max. efficiency occurs at three quarters of full load, calculate the efficiency at half load. P.f. of 0.8 at all load

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 3.11P: For the transformer in Problem 3.10. The open-circuit test with 11.5 kV applied results in a power...

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Concept explainers

Single Phase Transformer

A single-phase transformer is a type of power transformer. It is an electrical device that accepts converts the single phase alternating power into single phase alternating power. In this power conversion the voltage is stepped up or down. If the voltage is stepped up, the current will be stepped down and if the voltage is stepped down, the current will be stepped up.

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A 200 kva transformer has an efficiency of 98% at full load. If the max. efficiency occurs
at three quarters of full load, calculate the efficiency at half load. P.f. of 0.8 at all loads.

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