A three-phase synchronous generator was open-circuit and short-circuit tested. During an opencircuit test of the synchronous generator, rated voltage of 380 V was obtained for the field current of IfNL = 5 A while for a short-circuit test, rated current of 8 A was reached for the field current of IfSC = 6 A. The synchronous generator is connected to rated voltage of 380 V. Assuming negligible armature resistance determine: (a) internal voltage E, under rated current and power factor of 0.8 lagging; (b) for the internal voltage from (a) determine the steady-state stability limit; (c) at the steady-state stability limit in (b), determine reactive power of the generator, and generator loading in pu. Use rated power of the machine as the base.

A three-phase synchronous generator was open-circuit and short-circuit tested. During an opencircuit test of the synchronous generator, rated voltage of 380 V was obtained for the field current of IfNL = 5 A while for a short-circuit test, rated current of 8 A was reached for the field current of IfSC = 6 A. The synchronous generator is connected to rated voltage of 380 V. Assuming negligible armature resistance determine: (a) internal voltage E, under rated current and power factor of 0.8 lagging; (b) for the internal voltage from (a) determine the steady-state stability limit; (c) at the steady-state stability limit in (b), determine reactive power of the generator, and generator loading in pu. Use rated power of the machine as the base.

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

Chapter12: Power System Controls

Section: Chapter Questions

Problem 12.11P

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