9.1 The single-line diagram of a three-phase power system is shown in Figure 9.17. Equipment ratings are given as follows: Synchronous generators: GI 1000 MVA 15 kV G2 1000 MVA 15 kV G3 500 MVA 13.8 kV 13.8 kV G4 750 MVA Transformers: TI 1000 MVA T2 1000 MVA T3 500 MVA T4 750 MVA Transmission lines: 1-2 765 kV 1-3 765 kV 2-3 765 kV XX₂ = 0.18, X, -0.07 per unit X=X₂-0.20, X, 0.10 per unit XX₂ = 0.15, X, = 0.05 per unit X-0.30, X₂= 0.40, X, 0.10 per unit 15 kV A/765 kV Y 15 kV A/765 kV Y 15kV Y/765kVY 15 kV Y/765 kVY X = 0.10 per unit X = 0.10 per unit X = 0.12 per unit X= 0.11 per unit Χ = 50 Ω, X = 150 Ω X = 40 Ω, X = 100 Ω X = 100 Ω Χ, " 40 Ω, Line 1-3 Line 1-2 T₂ Line 2-3 The inductor connected to Generator 3 neutral has a reactance of 0.05 per unit using generator 3 ratings as a base. Find fault current occurs at bus 3 if: 1- L-G fault actual 2- L-L-G fault 3- L-L fault base. using a 1000-MVA, 765-kV base in the zone of line 1-2 25 ase والمسيرا FI Pr

9.1 The single-line diagram of a three-phase power system is shown in Figure 9.17. Equipment ratings are given as follows: Synchronous generators: GI 1000 MVA 15 kV G2 1000 MVA 15 kV G3 500 MVA 13.8 kV 13.8 kV G4 750 MVA Transformers: TI 1000 MVA T2 1000 MVA T3 500 MVA T4 750 MVA Transmission lines: 1-2 765 kV 1-3 765 kV 2-3 765 kV XX₂ = 0.18, X, -0.07 per unit X=X₂-0.20, X, 0.10 per unit XX₂ = 0.15, X, = 0.05 per unit X-0.30, X₂= 0.40, X, 0.10 per unit 15 kV A/765 kV Y 15 kV A/765 kV Y 15kV Y/765kVY 15 kV Y/765 kVY X = 0.10 per unit X = 0.10 per unit X = 0.12 per unit X= 0.11 per unit Χ = 50 Ω, X = 150 Ω X = 40 Ω, X = 100 Ω X = 100 Ω Χ, " 40 Ω, Line 1-3 Line 1-2 T₂ Line 2-3 The inductor connected to Generator 3 neutral has a reactance of 0.05 per unit using generator 3 ratings as a base. Find fault current occurs at bus 3 if: 1- L-G fault actual 2- L-L-G fault 3- L-L fault base. using a 1000-MVA, 765-kV base in the zone of line 1-2 25 ase والمسيرا FI Pr

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 9.1P

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