A 270 kVA transformer has primary and secondary winding resistances of 0.6Ω, and 0.0016Ω respectively. The iron loss is 2.25 KW and the primary and secondary voltages are 7kV and 320 V respectively. If the power factor of the load is 0.6 lag, find the efficiency of the transformer for 20% of full load.

A 270 kVA transformer has primary and secondary winding resistances of 0.6Ω, and 0.0016Ω respectively. The iron loss is 2.25 KW and the primary and secondary voltages are 7kV and 320 V respectively. If the power factor of the load is 0.6 lag, find the efficiency of the transformer for 20% of full 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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