4.33 Three single-phase, 10-kVA, 2400/120-V, 60-Hz transformers are connected to form a three-phase, 4160/208-V transformer bank. The equivalent impedance of each single-phase transformer referred to the primary side is 10+ j25 . The transformer bank delivers 27 kW at 208 V and 0.9 power factor leading. a. Draw the three-phase schematic diagram showing the transformer connection. Draw a per-phase equivalent circuit. b. Determine the primary current and power factor. c. Determine the primary voltage.

4.33 Three single-phase, 10-kVA, 2400/120-V, 60-Hz transformers are connected to form a three-phase, 4160/208-V transformer bank. The equivalent impedance of each single-phase transformer referred to the primary side is 10+ j25 . The transformer bank delivers 27 kW at 208 V and 0.9 power factor leading. a. Draw the three-phase schematic diagram showing the transformer connection. Draw a per-phase equivalent circuit. b. Determine the primary current and power factor. c. Determine the primary voltage.

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 3.31MCQ

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