At normal voltage and frequency, an 800 kVA single-phase transformer draws an input power of 7.5 kW on no-load. With reduced voltage applied and full-load current flowing in short- circuited secondary winding, it draws an input power of 14.2 kW. If the transformer operates on the following duty cycle in a day, calculate its all-day efficiency. Duration Load (kW) Load power factor (hours) 500 0.8 4 700 0.9 4 300 0.95 10 Nil

At normal voltage and frequency, an 800 kVA single-phase transformer draws an input power of 7.5 kW on no-load. With reduced voltage applied and full-load current flowing in short- circuited secondary winding, it draws an input power of 14.2 kW. If the transformer operates on the following duty cycle in a day, calculate its all-day efficiency. Duration Load (kW) Load power factor (hours) 500 0.8 4 700 0.9 4 300 0.95 10 Nil

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 3.28MCQ

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