A 100 kVA distribution transformer has an iron loss of 2.0 kW and a total load copper loss of 4.5 kW. During the day this transformer supplies a load of 80 kW at 0.8 power factor for 5 hours, a load of 42.5 kW at 0.85 power factor for 9 hours, a load of 21 kW at 0.7 power factor for 4 hours and the rest of the time the load is zero. So find its energy efficiency.

A 100 kVA distribution transformer has an iron loss of 2.0 kW and a total load copper loss of 4.5 kW. During the day this transformer supplies a load of 80 kW at 0.8 power factor for 5 hours, a load of 42.5 kW at 0.85 power factor for 9 hours, a load of 21 kW at 0.7 power factor for 4 hours and the rest of the time the load is zero. So find its energy efficiency.

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 3.15P: Rework Problem 3.14 if the transformer is delivering rated load at rated secondary voltage and at...

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