A 3-phase, 200 MVA, 44 kV, 50 Hz synchronous generator is operating under no load and excited to give the rated terminal voltage. A 3-phase, symmetrical short circuit develops at the terminals. The de and double frequency components are to be neglected. The generator has the following parameters in usual notations: X =1.0 pu X, =0.3 pu X =0.2 pu Tf =1.0 sec Tdw =0.04 sec (a) Find the initial rms current in Amperes. (b) The current after 4-cycles in Amperes.

A 3-phase, 200 MVA, 44 kV, 50 Hz synchronous generator is operating under no load and excited to give the rated terminal voltage. A 3-phase, symmetrical short circuit develops at the terminals. The de and double frequency components are to be neglected. The generator has the following parameters in usual notations: X =1.0 pu X, =0.3 pu X =0.2 pu Tf =1.0 sec Tdw =0.04 sec (a) Find the initial rms current in Amperes. (b) The current after 4-cycles in Amperes.

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

Chapter11: Transient Stability

Section: Chapter Questions

Problem 11.8P

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