An unloaded star connected solidly grounded 10 MVA, 11 KV generator has positive, negative and zero sequence impedances are j 1.3 Ω,j 0.8Ω and j 0.4Ω respectively. A single line to ground fault occurs at the terminals of the generator. (i) Calculate the fault current. (ii) Determine the value of the inductive reactance that must be inserted at the generator to limit the fault current to 50% of the value obtained in (i)

An unloaded star connected solidly grounded 10 MVA, 11 KV generator has positive, negative and zero sequence impedances are j 1.3 Ω,j 0.8Ω and j 0.4Ω respectively. A single line to ground fault occurs at the terminals of the generator. (i) Calculate the fault current. (ii) Determine the value of the inductive reactance that must be inserted at the generator to limit the fault current to 50% of the value obtained in (i)

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 9.2P

See similar textbooks

Similar questions

Last time i got wrong please help me
The sequence components of the fault current are as follows: Ipositive = j2 p.u., Inegative = - j0.5 p.u. and Izero = -j 1.5 p.u. The type of fault in the system is
A 13.2 kV, 60 Hz, 3-phase synchronous generator is connected in star and its neutral point is earthed while inductance per phase is 0.02 Henry. The generator is connected to a bus bar through a circuit breaker. The distributed capacitance up to circuit breaker between phase and neutral is 0.015 micro Farad. Determine the following: (i) Peak re-striking voltage (in kV) across the contact of circuit breaker; (ii) Frequency of oscillations (in kHz); (iii) Time to occurs first peak re-striking voltage (in micro second) and (iv) The average rate of rise of re-striking voltage (in mega volts per second)
A 12 MVA, 132/6.6 kV, transformer having a reactance of 0.15 pu is fed from an infinite bus. The transformer feeds two motor each 6 MVA, 6.6 kV. Each motors has a transient reactance of 0.14 pu and a subtransient reactance of 0.30 pu based on its own rating. A three phase balanced fault occurs at the terminals of one motor as shown in the figure below. Find the subtransient fault current and subtransient current in breaker. M1) 132/6.6 KV СВ 38 CB Infinite Bus M2 Fault
A generator operating at 60 Hz delivers 1 Pu MW power. Suddenly a three phase fault takes place reducing the maximum power transferable to 0.40 pu MW whereas before the fault, this power was l.8 pu MW and after the clearance of the fault, it is l.30 pu MW Determine the critical clearing angle
The negative sequence current of a solidly grounded generator for single line to ground fault is j 2.5 p.u. Then the current flow through the neutral during the fault is j 2.5 pu j0.75 pu j7.5 pu j0.25p.u
The negative sequence current of a solidly grounded generator for single line to ground fault is j 2.5 p.u. Then the positive sequence current during the fault is equal to o j7.5 pu o jo.75 pu o j2.5 pu o jo.25p.u
(9) An unloaded generator with a pre-fault voltage 1 pu has the following sequence impedance: Zo = 0.15 pu, Z₁ = Z₂ = 0.25 pu The neutral is grounded with a reactance of 0.05 pu. The fault current in pu for a single-line to ground fault is (a) 3.75 pu (b) 4.28 pu (d) 7 25 pu
A three phase fault is applied at the point P as shown in the figure. Find the criticalclearing angle for clearing the fault with simultaneous openings of the breakers 1 and 2. Thegenerator is delivering 1.0 pu at the instant preceding the fault
The zero sequence current of a generator for line to ground faults is j 3.0 p.u. Then the current through the neutral during the fault is
pls solve it before 10 min
A 15 MVA, 6.6 kV, wye connected generator has X 1 = X 2 = 20%and X 0 = 10%. The neutral of the generator is groundedthrough a reactor of 5% reactance based on the generatorrating. A double line-to-ground fault occurs at terminals band c. What is the current in the ground?