If the source impedance at a 13.2 kV distribution substation bus is (0:5 + 1:5) Q per phase, compute the RMS and maximum peak instantaneous value of the fault current, for a balanced three-phase fault. For the system (X/R) ratio of 3.0, the asymmetrical factor is 1.9495 and the time of peak is 7.1 ms (see Problem 1). Comment on the withstanding peak current capability to which all substation electrical equipment need to be designed.

If the source impedance at a 13.2 kV distribution substation bus is (0:5 + 1:5) Q per phase, compute the RMS and maximum peak instantaneous value of the fault current, for a balanced three-phase fault. For the system (X/R) ratio of 3.0, the asymmetrical factor is 1.9495 and the time of peak is 7.1 ms (see Problem 1). Comment on the withstanding peak current capability to which all substation electrical equipment need to be designed.

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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