A 3-phase short circuit fault at point E in a plant with single line representation below. consists of. Draw the impedance diagram pu of the system and calculate the short circuit current that will occur. calculate. (Ubaz 33 kV, Sbaz 10 MVA, take the voltage source as 1 pu) Uk: %8 5 MVA 33/15 kV Xd"=%12 Uk=%16 15 MVA 10 MVA over heo d line 10 kV A 10/33 kV B C D cable G1 TR1 TR2 havai hat 20 km. %2 6 km. Z=(0,12+j0,08)Q 1 pu Z=(0,18+j0,27)Q

A 3-phase short circuit fault at point E in a plant with single line representation below. consists of. Draw the impedance diagram pu of the system and calculate the short circuit current that will occur. calculate. (Ubaz 33 kV, Sbaz 10 MVA, take the voltage source as 1 pu) Uk: %8 5 MVA 33/15 kV Xd"=%12 Uk=%16 15 MVA 10 MVA over heo d line 10 kV A 10/33 kV B C D cable G1 TR1 TR2 havai hat 20 km. %2 6 km. Z=(0,12+j0,08)Q 1 pu Z=(0,18+j0,27)Q

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 9.54P

See similar textbooks

Similar questions

Equipment ratings for the five-bus power system shown in Figure 7.15 are as follows: Generator G1:Â Â Â Â 50Â MVA,Â 12kV,Â X=0.2 per unit Generator G2: 100Â MVA, 15 kV, X=0.2 per unit Transformer T1: 50 MVA, 10 kV Y/138kVY,X=0.10 per unit Transformer T2: 100 MVA, 15 kV /138kVY,X=0.10 per unit Each 138-kV line: X1=40 A three-phase short circuit occurs at bus 5, where the prefault voltage is 15 kV. Prefault load current is neglected. (a) Draw the positive-sequence reactance diagram in unit on a 100-MVA, 15-kV base in the zone of generator G2. Determine (b) the ThĂ©venin equivalent at the fault, (c) the subtransient fault current in per unit and in kA rms, and (d) contributions to the fault from generator G2 and from transformer T2.
Equipment ratings for the four-bus power system shown in Figure 7.14 are as follows: Generator G1: 500 MVA, 13.8 kV, X=0.20 per unit Generator G2: 750 MVA, 18 kV, X=0.18 per unit Generator G3: 1000 MVA, 20 kV, X=0.17 per unit Transformer T1: 500 MVA, 13.8/500YkV,X=0.12 per unit Transformer T2: 750 MVA, 18/500YkV,X=0.10 per unit Transformer T3: 1000Â MVA, 20/500YkV,X=0.10 per unit A three-phase short circuit occurs at bus 1, where the prefault voltage is 525 kV. Prefault load current is neglected. Draw the positive-sequence reactance diagram in per unit on a 1000-MVA, 20-kV base in the zone of generator G3. Determine (a) the ThĂ©venin reactance in per unit at the fault, (b) the subtransient fault current in per unit and in kA rms, and (c) contributions to the fault current from generator G1 and from line 1-2.
b) A fault occurs at bus 4 of the network shown in Figure Q3. Pre-fault nodal voltages throughout the network are of 1 + j0 p.u, and the impedance of the electric arc is neglected (Zf = 0 + j0 p.u.). The positive, negative and zero sequence impedance parameters of the generator, transmission lines and transformer are given in Figure Q3. (i) Determine the positive sequence fault current for the case when a three-phase-to-ground fault occurs at bus 4 of the network (ii) Determine the short-circuit fault current for the case when a one-phase- to-ground fault occurs at bus 4. Recall that phasors can be expressed in terms of their symmetrical components as shown in the picture attached. where F stands for any three-phase quantity (e.g., current, voltage) (iii) Determine the short-circuit fault current for the case when a phase-to-phase fault occurs at bus 4 ReplyForward
The single line diagram of a power system is shown in Figure Q2.1 including generator and transformer winding connection and earthing details. The parameters for this system have been calculated on a common 100 MVA base and are given in Table Q2.1. All resistances and shunt susceptances are neglected. This system experiences a single line to ground fault at a point F on line L1. The point F is at a distance d from Bus 4 along the line L1. The total length ?? of the line L1 is 50 km. Note that the location of ?? is not drawn to scale in Figure Q2.1. The fault current at the fault point F is measured to be 6.106 kA. i) Determine the zero, positive, and negative sequence Thevenin equivalent impedances as seen at the fault point F. These should be evaluated in per unit and shown as a function of d.ii) Use the sequence impedances calculated in part (i) to determine the distance d of the fault (in km) from Bus 4.
For the power system with a single line diagram; a) By choosing the base values of 1000 MVA and 20 kV in the Generator G3 region, the system is zero, Draw the reactance diagrams of the positive and negative sequence circuits. (for each line ?0 = ?1 = ?2 = 50 ?ℎ?) b) Find the Thevenin equivalents according to the fault condition in busbar 1.
Consider the single-line diagram of a power system shown below. The transient reactance of cach part of the system is as shown in table and expressed in p.u. on a common 100 MVA base. A three-phase fault with impedance of 0.16 p. occurs at bus (5). Determine short- circuit capacity (fault level) and short circuit current? Assume the fault voltage at bus (5) equal 112 KV
At a 220 kV substation of a power system, it is given that the three-phase fault level is 4000 MVA and single-line to ground fault level is 5000 MVA. Neglecting the resistance and the shunt susceptances of the system, (B) And the zero sequence driving point reactance at the bus is: (@)2.2Q (b) 4.84Q (€)18.18 Q (d)22.72Q
For the following single line diagram of a three-phase system, a three-phase fault occurs at point P and just before the fault the line voltage is 18 kV at P. Find out the transient fault current in pu and original value at point P. Take, the given kVA and kV of the G1 as the new base. Answer follow image.
For the following network, calculate the fault currents (IF1, IF2, IF3 and IF4) in pu and in kA, and circuit breaker ratings (i.e. fault MVA ) at the indicated locations. Internal reactance of generators are j0.9 pu. Base quantities: 11 kV, 400 MVA on the generator side.
Thévenin equivalent sequence networks looking into the faulted bus of a power system are given with ?1=?0.15 , ?2=?0.15 , ?0=?0.2and ?1=1∠0°per unit. Compute the fault currents and voltages for the followingfaults occurring at the faulted bus: (a) Balanced three-phase fault (b) Single line-to-ground fault (c) Line-line fault (d) Double line-to-ground fault Which is the worst fault from the viewpoint of the fault current?
The single line diagram of a power system is shown in Figure Q2.1 includinggenerator and transformer winding connection and earthing details. The parametersfor this system have been calculated on a common 100 MVA base and are given inTable Q2.1. All resistances and shunt susceptances are neglected. This systemexperiences a single line to ground fault at a point F on line L1. The point F is at adistance d from Bus 4 along the line L1. The total length l of the line L1 is 50 km.Note that the location of d is not drawn to scale in Figure Q2.1. The fault current atthe fault point F is measured to be 6.106 kA. i) Determine the zero, positive, and negative sequence Thevenin equivalentimpedances as seen at the fault point F. These should be evaluated in per unitand shown as a function of d.ii) Use the sequence impedances calculated in part (i) to determine the distance dof the fault (in km) from Bus 4. It's different from the answer, please don't send it
Given the 4 bus network shown below, assume that there are no loads and all buses are at the rated voltage and all have the same phase angles. Assume that shunt capacitances are neglected. The relevant transient reactances for the generators and the reactances for the transformers are shown. Solve for the fault current through the fault impedance for a fault at bus 4 with a fault impedance of j0.1 pu. HINT: Use Delta to Wye conversion.