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. d. Determine the voltage regulation.

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. d. Determine the voltage regulation.

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 3.14P: A single-phase 50-kVA,2400/240-volt,60-Hz distribution transformer is used as a step-down...

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