5.26 An unloaded generator with a pre-fault voltage 1 pu has the following sequence impedance: Z = 0.15 pu, Z, = Z, = j0.25 pu The neutral is grounded with a reactance of 0.05 pu. The fault current in pu for a single-line to %3D ground fault is (a) 3.75 pu (b) 4.28 pu (c) 6 pu (d) 7.25 pu

5.26 An unloaded generator with a pre-fault voltage 1 pu has the following sequence impedance: Z = 0.15 pu, Z, = Z, = j0.25 pu The neutral is grounded with a reactance of 0.05 pu. The fault current in pu for a single-line to %3D ground fault is (a) 3.75 pu (b) 4.28 pu (c) 6 pu (d) 7.25 pu

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

Chapter9: Unsymmetrical Faults

Section: Chapter Questions

Problem 9.32P: For the system of Problem 9.13, compute the fault current for the following faults at bus 3: (a) a...

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Question

5.26 An unloaded generator with a pre-fault voltage
ct
1 pu has the following sequence impedance:
Z, = j0. 15 pu, Z, = Z, = j0.25 pu
The neutral is grounded with a reactance of
0.05 pu. The fault current in pu for a single-line to
ground fault is
(a) 3.75 pu
(c) 6 pu
(b) 4.28 pu
(d) 7.25 pu

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