Practice Problem 1,2 A 60 - cycle, 150 kVA, three winding transformer is rated at 4,800 volts primary voltage, and there are two secondary windings, one rated at 720 Volts and the other at 240 Volts. There are 360 primary turns. The rating of each secondary winding is 75 kVA. Determine (a) turns in each secondary winding: (b) rated primary current at unity power factor; (c) rated primary current at 0.707 power factor lagging current; (d) rated current of the 600-Volt and 240-Volt secondaries at unity power factor. Answers: (c) I, = 31.25/-45" Amp. 104.167 /Q" Amp.; (a) NSI = 54 turnsi N = 18 turns (b) I, 31.25/0" Amp. (d) 312.5/0" Amp. %3!

Practice Problem 1,2 A 60 - cycle, 150 kVA, three winding transformer is rated at 4,800 volts primary voltage, and there are two secondary windings, one rated at 720 Volts and the other at 240 Volts. There are 360 primary turns. The rating of each secondary winding is 75 kVA. Determine (a) turns in each secondary winding: (b) rated primary current at unity power factor; (c) rated primary current at 0.707 power factor lagging current; (d) rated current of the 600-Volt and 240-Volt secondaries at unity power factor. Answers: (c) I, = 31.25/-45" Amp. 104.167 /Q" Amp.; (a) NSI = 54 turnsi N = 18 turns (b) I, 31.25/0" Amp. (d) 312.5/0" Amp. %3!

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 3.28MCQ

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