2. A 3-phase, 75 MVA, 11-8 kV star-connected alternator with a solidly earthed neutral point has th lowing p.u. impedances based on rated phase voltage and rated phase current : Positive phase sequence impedance j2 p.u. Negative phase sequence impedance j0-16 p.u. j 0-08 p.u. Zero phase sequence impedance Determine the steady-state fault current for the following : (i) 3-phase symmetrical short-circuit (i line-to-earth fault (iii) two line-to-earth fault. The generated e.m.f. per phase is equal to the rated vo [(01840 A (ii) 4920 A (iii) 35

2. A 3-phase, 75 MVA, 11-8 kV star-connected alternator with a solidly earthed neutral point has th lowing p.u. impedances based on rated phase voltage and rated phase current : Positive phase sequence impedance j2 p.u. Negative phase sequence impedance j0-16 p.u. j 0-08 p.u. Zero phase sequence impedance Determine the steady-state fault current for the following : (i) 3-phase symmetrical short-circuit (i line-to-earth fault (iii) two line-to-earth fault. The generated e.m.f. per phase is equal to the rated vo [(01840 A (ii) 4920 A (iii) 35

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

Chapter8: Symmetrical Components

Section: Chapter Questions

Problem 8.32P

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Similar questions

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