A synchronous generator operates initially at steady state with a mechanical power of 1pu and a corresponding maximum electrical power of 2.5 pu. Calculate the initial load angle. A three phase to earth fault occurs on the associated bus reducing the maximum electrical power to 0.9 pu. After the clearance of the fault by automatic switchgear operation the maximum electrical power rises to 2.1 pu. Calculate the load angle after the clearance of the fault. Calculate the critical clearing angle. Calculate also the accelerating and decelerating areas. Comment on the accelerating and decelerating areas.

A synchronous generator operates initially at steady state with a mechanical power of 1pu and a corresponding maximum electrical power of 2.5 pu. Calculate the initial load angle. A three phase to earth fault occurs on the associated bus reducing the maximum electrical power to 0.9 pu. After the clearance of the fault by automatic switchgear operation the maximum electrical power rises to 2.1 pu. Calculate the load angle after the clearance of the fault. Calculate the critical clearing angle. Calculate also the accelerating and decelerating areas. Comment on the accelerating and decelerating areas.

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

Chapter7: Symmetrical Faults

Section: Chapter Questions

Problem 7.6MCQ

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