3.6. A 60-KVA, 4800/2400-V single-phase transformer gave the following test results: 1. Rated voltage is applied to the low voltage winding and the high volt- age winding is open-circuited. Under this condition, the current into the low voltage winding is 2.4 A and the power taken from the 2400 V source is 3456 W. 2. A reduced voltage of 1250 V is applied to the high voltage winding and the low voltage winding is short-circuited. Under this condition, the current flowing into the high voltage winding is 12.5 A and the power taken from the 1250 V source is 4375 W. (a) Determine parameters of the equivalent circuit referred to the high volt- age side. (b) Determine voltage regulation and efficiency when transformer is operat- ing at full-load, 0.8 power factor lagging, and a terminal voltage of 2400 V. (c) What is the load kVA for maximum efficiency and the maximum effi- ciency at 0.8 power factor? (d) Determine the efficiency when transformer is operating at 3/4 full-load, 0.8 power factor lagging, and a terminal voltage of 2400 V.

3.6. A 60-KVA, 4800/2400-V single-phase transformer gave the following test results: 1. Rated voltage is applied to the low voltage winding and the high volt- age winding is open-circuited. Under this condition, the current into the low voltage winding is 2.4 A and the power taken from the 2400 V source is 3456 W. 2. A reduced voltage of 1250 V is applied to the high voltage winding and the low voltage winding is short-circuited. Under this condition, the current flowing into the high voltage winding is 12.5 A and the power taken from the 1250 V source is 4375 W. (a) Determine parameters of the equivalent circuit referred to the high volt- age side. (b) Determine voltage regulation and efficiency when transformer is operat- ing at full-load, 0.8 power factor lagging, and a terminal voltage of 2400 V. (c) What is the load kVA for maximum efficiency and the maximum effi- ciency at 0.8 power factor? (d) Determine the efficiency when transformer is operating at 3/4 full-load, 0.8 power factor lagging, and a terminal voltage of 2400 V.

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 3.11MCQ: For a short-circuit test on a 2-winding transformer, with one winding shorted, can you apply the...

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