X=2Y=8 b) A fault occurs at bus 2 of the network shown in Figure Q3. Pre-fault nodalvoltages throughout the network are of 1 p.u. and the impedance of theelectric arc is neglected. Sequence impedance parameterstransmission lines, and transformer are given in Figure Q3, where X and Y arethe last two digits of your student number.the generator,JX20 0.1X p.u.jXa= j0.1X p.u.Xaoy - J0.2Y p.u,%3DV, 120° p.u. V, 120° p.u.V,-120° p.u.jX4)-70.2X p.u.Xn= /0.25 p.u.i A1 2 Xae /0.25 p.u. 3jXo)-j0.3 p.u.Xaz= j0.2X p.u.jX40 /0.2Y p.u.jXT0)-/0.2Y p.u.jXr2 /0.2Y p.u.jXT1 j0.2Y p.u.jX) 0.1X p.u.jX2 0.1X p.u.jXpo) = J0.05 p.u.Figure Q3. Circuit for problem 3b).For example, if your student number is c1700123, then:jXa1) = j0.22 p.u., jXa2) j0.22 p.u., and jXaco) = j0.23 p.u.()Assuming a balanced excitation, draw the positive, negative and zerosequence Thévenin equivalent circuits as seen from bus 2.(i)Determine the positive sequence fault current for the case when a three-phase-to-ground fault occurs at bus 2 of the network.(iii) Determine the short-circuit fault current for the case when a one-phase-to-ground fault occurs at bus 2.

Answered: Image /qna-images/answer/0706a78c-b12c-431f-9b3b-95bc6e395710.jpg

b) A fault occurs at bus 2 of the network shown in Figure Q3. Pre-fault nodal voltages throughout the network are of 1 p.u. and the impedance of the electric arc is neglected. Sequence impedance parameters of the generator, transmission lines, and transformer are given in Figure Q3, where X and Y are the last two digits of your student number. JX20)- /0.1X p.u. jX2 0.1X p.u. Xao)- J0.2Y p.u. %3D %3D V= 120° p.u. V 120° p.u. V, 120° p.u. jXa) /0.2X p.u. iXa2 j0.2X p.u. jX40) 0.2Y p.u. !! jXn)= 10.25 p.u. i A 2 Xng 0.25 p.u. 3 jXno)- j0.3 p.u. 0 X-70.2Y p.u. XT2- /0.2Y p.u. jXT1=70.2Y p.u. jXp)" J0.1X p.u. Xp- 0.1X p.u. Xo - /0.05 p.u. 0- %D !! 0. Figure Q3. Circuit for problem 3b). For example, if your student number is c1700123, then: jXa1) = j0.22 p.u., jXa(2) j0.22 p.u., and jXaco) = j0.23 p. u. %3D %3D (i) Assuming a balanced excitation, draw the positive, negative and zero (1) sequence Thévenin equivalent circuits as seen from bus 2. (i1) Determine the positive sequence fault current for the case when a three- phase-to-ground fault occurs at bus 2 of the network. (iii) Determine the short-circuit fault current for the case when a one-phase- to-ground fault occurs at bus 2.

b) A fault occurs at bus 2 of the network shown in Figure Q3. Pre-fault nodal voltages throughout the network are of 1 p.u. and the impedance of the electric arc is neglected. Sequence impedance parameters of the generator, transmission lines, and transformer are given in Figure Q3, where X and Y are the last two digits of your student number. JX20)- /0.1X p.u. jX2 0.1X p.u. Xao)- J0.2Y p.u. %3D %3D V= 120° p.u. V 120° p.u. V, 120° p.u. jXa) /0.2X p.u. iXa2 j0.2X p.u. jX40) 0.2Y p.u. !! jXn)= 10.25 p.u. i A 2 Xng 0.25 p.u. 3 jXno)- j0.3 p.u. 0 X-70.2Y p.u. XT2- /0.2Y p.u. jXT1=70.2Y p.u. jXp)" J0.1X p.u. Xp- 0.1X p.u. Xo - /0.05 p.u. 0- %D !! 0. Figure Q3. Circuit for problem 3b). For example, if your student number is c1700123, then: jXa1) = j0.22 p.u., jXa(2) j0.22 p.u., and jXaco) = j0.23 p. u. %3D %3D (i) Assuming a balanced excitation, draw the positive, negative and zero (1) sequence Thévenin equivalent circuits as seen from bus 2. (i1) Determine the positive sequence fault current for the case when a three- phase-to-ground fault occurs at bus 2 of the network. (iii) Determine the short-circuit fault current for the case when a one-phase- to-ground fault occurs at bus 2.

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 9.19P

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Similar questions

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