A 3 phase, 50 Hz, 50 MVA, 11 kV, alternator has a solidly grounded neutral with zero, positive, negative sequence reactance's of j0.05 p.u , jo.2 p.u and j0.12 p.u respectively. It is desired to limit the double line to ground fault current to 75% of three phase fault current. Calculate the ohmic value of reactance that must be placed between the alternator neutral and ground.

A 3 phase, 50 Hz, 50 MVA, 11 kV, alternator has a solidly grounded neutral with zero, positive, negative sequence reactance's of j0.05 p.u , jo.2 p.u and j0.12 p.u respectively. It is desired to limit the double line to ground fault current to 75% of three phase fault current. Calculate the ohmic value of reactance that must be placed between the alternator neutral and ground.

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 7.2MCQ: Even though the fault current is not symmetrical and not strictly periodic, the rms asymmetrical...

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