Q5 (b) A synchronous generator and a motor are both rated at 30MVA, 2kV and both have transient reactance of 20%. The transmission line connecting them has a reactance of 10% on the base of the machine ratings. The motor is drawing 20MW at 0.8 power factor lagging and a terminal voltage of 12.8kV when a symmetrical three-phase fault occurs at the motor terminals. Using the internal voltage of the machines, carry out design calculations to determine: 1. The prefault generator terminal voltage. 2. The sub-transient current in the generator and the motor. 3. The total fault current

Q5 (b) A synchronous generator and a motor are both rated at 30MVA, 2kV and both have transient reactance of 20%. The transmission line connecting them has a reactance of 10% on the base of the machine ratings. The motor is drawing 20MW at 0.8 power factor lagging and a terminal voltage of 12.8kV when a symmetrical three-phase fault occurs at the motor terminals. Using the internal voltage of the machines, carry out design calculations to determine: 1. The prefault generator terminal voltage. 2. The sub-transient current in the generator and the motor. 3. The total fault current

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

Chapter7: Symmetrical Faults

Section: Chapter Questions

Problem 7.3MCQ: The amplitude of the sinusoidal symmetrical ac component of the three-phase short-circuit current of...

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