A 30MVA, 3-phase, 50HZ 13.8kV, star-connected synchronous generator has positive, negative and zero sequence reactance, 15%, 15% and 5% respectively. A reactance (X,) is connected between the neutral of the generator and ground. A double line to ground fault takes place involving phases 'b' and 'c', with a fault impedance of jo.1 p.u. The value of X,(in p.u) that will limit the positive sequence generator current to 4270 A is Ans: 1.108

A 30MVA, 3-phase, 50HZ 13.8kV, star-connected synchronous generator has positive, negative and zero sequence reactance, 15%, 15% and 5% respectively. A reactance (X,) is connected between the neutral of the generator and ground. A double line to ground fault takes place involving phases 'b' and 'c', with a fault impedance of jo.1 p.u. The value of X,(in p.u) that will limit the positive sequence generator current to 4270 A is Ans: 1.108

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 8.34P

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