A 20-MVA, 13.8-kV generator has a direct-axis subtransient reactance (X") of 0.25 per unit. The negat and zero-sequence reactances are, respectively, 0.35 and 0.10 per unit. The neutral of the generator is solidly grounded. Determine: 1. The subtransient current in the generator when a three-phase fault occurs at the generator terminals. 2. The subtransient current in the generator when a single line-to-ground fault occurs at the generator terminals.

A 20-MVA, 13.8-kV generator has a direct-axis subtransient reactance (X") of 0.25 per unit. The negat and zero-sequence reactances are, respectively, 0.35 and 0.10 per unit. The neutral of the generator is solidly grounded. Determine: 1. The subtransient current in the generator when a three-phase fault occurs at the generator terminals. 2. The subtransient current in the generator when a single line-to-ground fault occurs at the generator terminals.

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

Chapter9: Unsymmetrical Faults

Section: Chapter Questions

Problem 9.20P

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