A 150-kVA transformer has a core loss of 8 kW and a copper loss of 22 kW at full load. a. What is the kVA rating at the maximum efficiency of the transformer? b. Express the load current at maximum efficiency as a percent of the rated current. If the transformer operates at a power factor of 0.9 lagging, c. Determine the maximum efficiency and d. the full-load efficiency of the transformer.

A 150-kVA transformer has a core loss of 8 kW and a copper loss of 22 kW at full load. a. What is the kVA rating at the maximum efficiency of the transformer? b. Express the load current at maximum efficiency as a percent of the rated current. If the transformer operates at a power factor of 0.9 lagging, c. Determine the maximum efficiency and d. the full-load 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 3.11P: For the transformer in Problem 3.10. The open-circuit test with 11.5 kV applied results in a power...

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