A single phase stepped-down transformer rating 500 kVA have a primary and secondary winding resistances 0.5 Ω and 0.02Ω, respectively. The primary and secondary voltage are 11 kV and 400 V, respectively. Consider core loss 5.0 kW. i. Explain the difference between core loss and copper loss. ii. If the power factor is 0.8, estimate the efficiency at full load and half load.

A single phase stepped-down transformer rating 500 kVA have a primary and secondary winding resistances 0.5 Ω and 0.02Ω, respectively. The primary and secondary voltage are 11 kV and 400 V, respectively. Consider core loss 5.0 kW. i. Explain the difference between core loss and copper loss. ii. If the power factor is 0.8, estimate the efficiency at full load and half 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 3.9P

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