QUESTION 5a) Obtain the sequence networks reduced to their Thevenin equivalents for the systemshown in Figure 4 in the case of a fault at F. Prefault is VF = 1.05Z 0° per unit.System data in per unit on the same base are given as follows:G1 : XI = 0.2 p.u.G2 : XI = 0.33 p.u.X2 = 0.12 p.u.X2 = 0.22 p.u.Хо - 0.06 р.u.Хо- 0.066 р.u.T1:XI =X2 = Xo = 0.2 p.u.T2:X = X2 = Xo 0.225 p.u.T3 :X1 =X2 = Xo = 0.27 p.u.T4 :X1 = X2 = Xo = 0.16 p.u.L1 :XI = X2 = 0.14 p.u. Xo = 0.3 p.u.L2 :X1 = X2 0.35 p.u. Xo = 0.6 p.u.T1T2L1G1G2L2T4T3Figure 4b) Calculate the per-unit subtransient fault current in phase a, b, c for a bolted threephase to ground short circuit at fault F in Figure 4. Justify your answer.

Answered: Image /qna-images/answer/f5f744ca-e581-4e4d-a262-a715d04cc183.jpg

QUESTION 5 a) Obtain the sequence networks reduced to their Thevenin equivalents for the system shown in Figure 4 in the case of a fault at F. Prefault is VF = 1.05Z 0° per unit. System data in per unit on the same base are given as follows: G1 : Xi = 0.2 p.u. G2 : XI = 0.33 p.u. X — 0.12 р.u. Х 3D0.22 р.u. Xo = 0.06 p.u. Xo = 0.066 p.u. T1:X1 =X2 = Xo = 0.2 p.u. T2 :XI =X2 = Xo = 0.225 p.u. T3: XI =X2 = Xo = 0.27 p.u. T4 :XI = X2 = Xo = 0.16 p.u. Li :XI = X2 = 0.14 p.u. Xo = 0.3 p.u. L2:X1 = X2 = 0.35 p.u. Xo = 0.6 p.u. T1 T2 L1 G1 G2 F L2 T4 T3 Figure 4 b) Calculate the per-unit subtransient fault current in phase a, b, c for a bolted three phase to ground short circuit at fault F in Figure 4. Justify your answer.

QUESTION 5 a) Obtain the sequence networks reduced to their Thevenin equivalents for the system shown in Figure 4 in the case of a fault at F. Prefault is VF = 1.05Z 0° per unit. System data in per unit on the same base are given as follows: G1 : Xi = 0.2 p.u. G2 : XI = 0.33 p.u. X — 0.12 р.u. Х 3D0.22 р.u. Xo = 0.06 p.u. Xo = 0.066 p.u. T1:X1 =X2 = Xo = 0.2 p.u. T2 :XI =X2 = Xo = 0.225 p.u. T3: XI =X2 = Xo = 0.27 p.u. T4 :XI = X2 = Xo = 0.16 p.u. Li :XI = X2 = 0.14 p.u. Xo = 0.3 p.u. L2:X1 = X2 = 0.35 p.u. Xo = 0.6 p.u. T1 T2 L1 G1 G2 F L2 T4 T3 Figure 4 b) Calculate the per-unit subtransient fault current in phase a, b, c for a bolted three phase to ground short circuit at fault F in Figure 4. Justify your answer.

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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