5. A 150 kVA transformer has iron-loss of 1-4 kW and full-load copper loss of 2-8 kW. Calculate (1) the efficiency of transformer at full-load (ii) the maximum efficiency of the transformer and (iii) the output power at the maximum level of efficiency. Assume unity power factor. [(1) 97-2 % (ii) 98-13 % (iii) 106-05 kW]

5. A 150 kVA transformer has iron-loss of 1-4 kW and full-load copper loss of 2-8 kW. Calculate (1) the efficiency of transformer at full-load (ii) the maximum efficiency of the transformer and (iii) the output power at the maximum level of efficiency. Assume unity power factor. [(1) 97-2 % (ii) 98-13 % (iii) 106-05 kW]

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 3.57P: A two-winding single-phase transformer rated 60kVA,240/1200V,60Hz, has an efficiency of 0.96 when...

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