An alternator and synchronous motor each rated for 50 MVA, 13.2 kV having subtransient reactance of 20% are connected through a transmission link of reactance 10% on the base of machine ratings. The motor is delivering a load of 30 MW at 0.8 pf lead and terminal voltage 12.5 kV when a 3-phase fault takes place at the motor terminals. Determine the subtransient current in the generator, motor and the fault. Ans: 6023.3 A, 11470.16 A, 17247.54 A

An alternator and synchronous motor each rated for 50 MVA, 13.2 kV having subtransient reactance of 20% are connected through a transmission link of reactance 10% on the base of machine ratings. The motor is delivering a load of 30 MW at 0.8 pf lead and terminal voltage 12.5 kV when a 3-phase fault takes place at the motor terminals. Determine the subtransient current in the generator, motor and the fault. Ans: 6023.3 A, 11470.16 A, 17247.54 A

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 3.56P: Three single-phase two-winding transformers, each rated 3kVA,220/110volts,60Hz, with a 0.10 per-unit...

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