there is a Line to Ground fault in a network, and it is found that the zero sequence current of a generator is 10<0° A, we can say that A) The current flowing in the generator from neutral to ground is zero. B) The generator has a floating neutral. C) The current flowing in the generator from neutral to ground is 10<0° A. D) The current flowing in the generator from neutral to

there is a Line to Ground fault in a network, and it is found that the zero sequence current of a generator is 10<0° A, we can say that A) The current flowing in the generator from neutral to ground is zero. B) The generator has a floating neutral. C) The current flowing in the generator from neutral to ground is 10<0° A. D) The current flowing in the generator from neutral to

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 7.10P

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The one-line diagram of a simple power system is shown in Figure below. The neutral of each generator is grounded through a current-limiting reactor of 0.25/3 per unit on a 100-MVA base. The system data expressed in per unit on a common 100-MVA base is tabulated below. The generators are running on no-load at their rated voltage and rated frequency with their emfs in phase. G Stark Item Base MVA Voltage Rating X' x² 20 kV 20 kV 20/220 kV 20/220 kV 100 0.05 0.15 0.15 0.10 0.10 220 kV 0.125 0.125 0.30 0.15 0.25 025 0.7125 0.15 100 100 0.15 0.05 0.10 0.10 0.10 100 0.10 100 100 Lu La 220 kV 0.15 220 kV 0.35 100 A balanced three-phase fault at bus 3 through a fault impedance Zf= jo.I per unit. The magnitude of the fault current in amperes in phase b for this fault is: Select one: A. 345.3 B. 820.1 C. 312500 3888888 产产

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