Due to the failure of circuit breaker the two phases of bus bar connected to generator are short circuited through fault impedance of jo.12 According to what would be the voltage at another phase ? Select one: O a. Equal voltages in all the three phases O b. Zero voltages in all the three phases O c. Low voltage compared to other two phases O d. High voltage compared to other two phases

Due to the failure of circuit breaker the two phases of bus bar connected to generator are short circuited through fault impedance of jo.12 According to what would be the voltage at another phase ? Select one: O a. Equal voltages in all the three phases O b. Zero voltages in all the three phases O c. Low voltage compared to other two phases O d. High voltage compared to other two phases

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 9.13P: Consider the oneline diagram of a simple power system shown in Figure 9.20. System data in per-unit...

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In a power system the fault is occurred in all the lines and to the ground without fault impedance at bus-2 and it is found that the positive sequence fault current as j2.15. According to you what could be the current in Phase-A at bus -2? Select one: O a. -j2.15 O b. Infinity O C. +j2.15 O d. 0
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Q2. The single-line diagram of a simple three-bus power system is shown in Figure-2. Each generator is represented by an emf behind the sub-transient reactance. All impedances are expressed in per unit on a common MVA base. All resistances and shunt capacitances are neglected. The generators are operating on no load at their rated voltage with their emfs in phase. A three-phase fault occurs at bus 3 through a fault impedance of Zf = j0.19 per unit. (i) Using Th'evenin's theorem, obtain the impedance to the point of fault and the fault current in (ii) Determine the bus voltages per unit. ) j0.05 j0.075 j0.75 2 j0.30 j0.45 Figure-2: Single line diagram of the power system network for Q2 3
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7.In a line-to-ground fault we can expect that A) There are no currents to ground. B) The voltages at the fault point with respect to ground are zero in all three phases. C) The current in the faulted phase flows to ground. D) There are short circuit currents in all three phases. E) N. A.
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Single line to ground fault of a solidly grounded generator positive sequence current is j2.5 p.u, then the current flow in the neutral during the fault is O j1.05 p.u O jo.25 p.u O j2.5 p.u O j7.5 p.u
1-The following sequence currents were recorded in a power system under a fault condition Ipositive=j1.5pu, Inegative=–j0pu, Izero=– j0pu. The fault is a.Three-phase b.Double Line to ground c.Line to ground d.Line to line also if this case 2- he following sequence currents were recorded in a power system under a fault condition Ipositive=j1.5pu, Inegative=j0pu, Izero=j0pu. The fault is a.Three-phase b.Double Line to ground c.Line to ground d.Line to line i uploded the houndots (book )here :https://seomidea.com/hct/nu.pdf