An 22kV, 100 MVA alternator is provided with differential protection. The percentage of winding be protected against phase to ground fault is 75%. The relay is set to operate when there is 20% out of balance current. Determine the value of the resistance to be placed in the neutral to ground connection.

An 22kV, 100 MVA alternator is provided with differential protection. The percentage of winding be protected against phase to ground fault is 75%. The relay is set to operate when there is 20% out of balance current. Determine the value of the resistance to be placed in the neutral to ground connection.

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

Chapter10: System Protection

Section: Chapter Questions

Problem 10.27P

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