Q2:- a synchronous generator is 25 MVA, 11kV, it is star- connected with the neutral point solidly grounded the generator is operating at no load rated voltage. Its reactances are X₁ = X₂ = 0.2 and Xo = 0.08 pu, calculate : a) The symmetrical sub transient line currents for SLG, LL, LLG and symmetrical three phase current. b) The value of reactance to be included in the generator neutral and grounded, so that line to ground fault current equals to the three phase fault current what will be the value of ground resistance to achieve the same condition ? c) With reactance value calculated in (b) included between neutral and ground. Calculate the line to line current and double line to ground fault current.

Q2:- a synchronous generator is 25 MVA, 11kV, it is star- connected with the neutral point solidly grounded the generator is operating at no load rated voltage. Its reactances are X₁ = X₂ = 0.2 and Xo = 0.08 pu, calculate : a) The symmetrical sub transient line currents for SLG, LL, LLG and symmetrical three phase current. b) The value of reactance to be included in the generator neutral and grounded, so that line to ground fault current equals to the three phase fault current what will be the value of ground resistance to achieve the same condition ? c) With reactance value calculated in (b) included between neutral and ground. Calculate the line to line current and double line to ground fault current.

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

Chapter6: Power Flows

Section: Chapter Questions

Problem 6.48P

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