QUESTION #2: A 50 MVA, 11 kV, 3 phase alternator has a direct subtransient reactances of 0.1 pu. The negative and zero sequences reactances are 0.15 and 0.25 pu respectively. The neutral of the generator is solidly earthed. Determine the subtransient current in the generator and the line to line voltages for subtransient conditions when a single line to ground fault occurs at the generator terminals with the generator operating unloaded at rated voltage.

QUESTION #2: A 50 MVA, 11 kV, 3 phase alternator has a direct subtransient reactances of 0.1 pu. The negative and zero sequences reactances are 0.15 and 0.25 pu respectively. The neutral of the generator is solidly earthed. Determine the subtransient current in the generator and the line to line voltages for subtransient conditions when a single line to ground fault occurs at the generator terminals with the generator operating unloaded at rated voltage.

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 3.35P: Consider a bank of this single-phase two-winding transformers whose high-voltage terminals are...

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Concept explainers

Synchronous Generator

In comparison to an asynchronous generator, it is a machine where the rotor speed is equal to the rotating magnetic field produced by the stator, i.e., mechanical speed is equal to the electrical speed, thus called synchronous, and not asynchronous.

Salient Pole Rotor

Salient pole rotor includes a large number of exposed poles mounted on a magnetic wheel. The construction of a bright pole is as shown in the image on the left. The proposed poles are made of metal laminations. The rotor winding is provided on these poles and is supported by pole shoes.

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