A three-phase short circuit occurs at point P for the system shown in the following figure. (a) Assuming the new bases as 30 MVA and 15 kV from the generator side, draw the per unit impedance diagram. (b) Just before the fault, the voltage at point P was 65 kV. Neglecting pre-fault currents, determine the sub-transient fault current. Also determine the contribution to the fault current from the generator and motor side.

A three-phase short circuit occurs at point P for the system shown in the following figure. (a) Assuming the new bases as 30 MVA and 15 kV from the generator side, draw the per unit impedance diagram. (b) Just before the fault, the voltage at point P was 65 kV. Neglecting pre-fault currents, determine the sub-transient fault current. Also determine the contribution to the fault current from the generator and motor side.

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 7.17P

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