The Y/Y connected 3-phase step-up transformer has a rating of 1200 MVA, operating at 33 kV/340 kV and 60 Hz. Its impedance is characterized solely by a reactance of 11.5 percent. Its purpose is to increase the voltage from a generating station in order to supply power to a 340 kV transmission line. Answer the following questions: a) Draw and determine the equivalent circuit of this transformer, per phase, in per-unit. b) Using the per-unit method, determine the generator terminal voltage when the high-voltage (HV) side of the transformer supplies 800 MVA at a power factor of 0.90 with a lagging angle, and the voltage is 360 kV. Hint: Select the nominal voltage as a base voltage, and the nominal power rating as a base power.

The Y/Y connected 3-phase step-up transformer has a rating of 1200 MVA, operating at 33 kV/340 kV and 60 Hz. Its impedance is characterized solely by a reactance of 11.5 percent. Its purpose is to increase the voltage from a generating station in order to supply power to a 340 kV transmission line. Answer the following questions: a) Draw and determine the equivalent circuit of this transformer, per phase, in per-unit. b) Using the per-unit method, determine the generator terminal voltage when the high-voltage (HV) side of the transformer supplies 800 MVA at a power factor of 0.90 with a lagging angle, and the voltage is 360 kV. Hint: Select the nominal voltage as a base voltage, and the nominal power rating as a base power.

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 3.16P: A single-phase, 50-kVA,2400/240-V,60-Hz distribution transformer has the following parameters:...

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