A three-phase alternator has a nameplate rating of 10MVA, 4160V, 10%X and is connected to a step up transformer T1 with a rating of 5MVA, 4.16kV/110kV, 20%X. The high voltage side of the transformer T1 is connected to a 40km transmission line with resistance of 0.1 ohm per km and reactance of 1 ohm per km. At the end of the transmission line, the transmission line is connected to a step-down transformer T2 with a rating of 5MVA, 110kV/34.5kV, 15% X. The low voltage side of transformer T2 is connected to a synchronous motor with a rating of 1MVA, 34.5kV, 50%X. Neglecting 30-degree phase shift between phase and line voltage, if the voltage at the terminals of the synchronous motor is 34kV at 0.95 leading at full load, determine: a. the current at the HV side and LV side of transformer T1 in Amperes. b. back emf of the synchronous motor in kV. c. generated emf and terminal voltage of the alternator in kV.

A three-phase alternator has a nameplate rating of 10MVA, 4160V, 10%X and is connected to a step up transformer T1 with a rating of 5MVA, 4.16kV/110kV, 20%X. The high voltage side of the transformer T1 is connected to a 40km transmission line with resistance of 0.1 ohm per km and reactance of 1 ohm per km. At the end of the transmission line, the transmission line is connected to a step-down transformer T2 with a rating of 5MVA, 110kV/34.5kV, 15% X. The low voltage side of transformer T2 is connected to a synchronous motor with a rating of 1MVA, 34.5kV, 50%X. Neglecting 30-degree phase shift between phase and line voltage, if the voltage at the terminals of the synchronous motor is 34kV at 0.95 leading at full load, determine: a. the current at the HV side and LV side of transformer T1 in Amperes. b. back emf of the synchronous motor in kV. c. generated emf and terminal voltage of the alternator in kV.

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 3.26P: A bank of three single-phase transformers, each rated 30MVA,38.1/3.81kV, are connected in Y- with a...

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