1. A 50 KVA, 1100/220 V, single-phase transformer is used to serve a prime subdivision. The core loss is 4050 W and the primary impedance of 0.15 + j 0.24 ohms and secondary impedance of 0.13 + j 0.18 ohm. Calculate: A. Calculate the full-load copper loss. B. Calculate the efficiency at full-load at 0.85 power factor lagging. C. Calculate the efficiency at half-load at 0.9 power factor lagging. D. Calculate the maximum efficiency at 0.8 power factor lagging. E. Calculate the efficiency at 35 KW loading, 0.707 power factor lagging.

1. A 50 KVA, 1100/220 V, single-phase transformer is used to serve a prime subdivision. The core loss is 4050 W and the primary impedance of 0.15 + j 0.24 ohms and secondary impedance of 0.13 + j 0.18 ohm. Calculate: A. Calculate the full-load copper loss. B. Calculate the efficiency at full-load at 0.85 power factor lagging. C. Calculate the efficiency at half-load at 0.9 power factor lagging. D. Calculate the maximum efficiency at 0.8 power factor lagging. E. Calculate the efficiency at 35 KW loading, 0.707 power factor lagging.

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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