For the four bus system as shown in Fig. Determine the fault current when the fault takes place at bus no.3 with fault impedance Zf =0 p.u. The Subtransient reactance of the generators and positive sequence reactance of other elements are given. Assume prefault Votage Eth= 120° p.u Generator X = j0.11p.u ; Transmission line X = j0.29p.u ; Transformer X = j0.37p.u G2 A

For the four bus system as shown in Fig. Determine the fault current when the fault takes place at bus no.3 with fault impedance Zf =0 p.u. The Subtransient reactance of the generators and positive sequence reactance of other elements are given. Assume prefault Votage Eth= 120° p.u Generator X = j0.11p.u ; Transmission line X = j0.29p.u ; Transformer X = j0.37p.u G2 A

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

Chapter12: Power System Controls

Section: Chapter Questions

Problem 12.13P

See similar textbooks

Similar questions

The sample large power system network data's are given below, The total number of buses is 5 Three-phase short circuit fault subjected at the bus 5 The initial voltage of the faulted bus is 1.0 p.u The Zbus matrix element Z55 is 0.704 p.u Fault impedance Zf= 0.33 p.u Fault current (If )in p.u ..........
b) The one-line diagram for a simple power system is given in Figure 1(b). į. Draw the impedance diagram of the system. i. Construct the bus admittance matrix, Xeus and bus impedance matrix, Zous of the system. I. Evaluate the fault current, bus voltages and line current during the flow when a balanced three-phase fault occurs on bus 1. bus 1 bus 2 j65 N G G 25 MVA 25 MVA 13.8 kV 15% 13.2/69 kV 11% 25 MVA 69/13.2 kV 11% 15 MVA 13 kV 15% Figure 1(b) m
b) A fault occurs at bus 4 of the network shown in Figure Q3. Pre-fault nodal voltages throughout the network are of 1 p.u. and the impedance of the electric arc is neglected. Sequence impedance parameters of the generator, transmission lines, and transformer are given in Figure Q3, where X and Y are the last two digits of your student number. jX(1) j0.1Y p.u. jX2)= j0.1Y p.u. jXko) = j0.1X p.u. V₁ = 120° p.u. V₂ = 120° p.u. (i) (ii) 0 jX(1) = j0.2 p.u. 1 jx(2) j0.2 p.u. 2 jX1(0) = j0.25 p.u. jXT(1) jXT(2) 종 3 j0.1X p.u. JX3(1) j0.1Y p.u. j0.1X p.u. JX3(2) j0.1Y p.u. jXT(0) j0.1X p.u. JX3(0)=j0.15 p.u. 0 = x = 1, jX2(1) j0.2Y p.u. V₁=1/0° p.u. jX(2(2) = j0.2Y p.u. jX2(0) = j0.3X p.u. = V3 = 120° p.u. Figure Q3. Circuit for problem 3b). For example, if your student number is c1700123, then: y = 7 = = jXa(r) = j0.13 p.u., jXa(z) = j0.13 p. u., and jXa(o) = j0.12 p. u. Assuming a balanced excitation, draw the positive, negative and zero sequence Thévenin equivalent circuits as seen from…
A hydro powered 50 MVA generator, with a synchronous reactance 0.33 p.u., delivers 40 MW over a transmission line of 0.15 p.u. reactance to an infinite system. A 3-phase short circuit transient fault occurs on the busbar between the generator and transmission line. Given that the generator emf is 1.4 p.u. prior to and during the fault and all reactances are to a 50 MVA base: Sketch the single line schematic diagram of the system. Determine the maximum load angle the generator can swing to without losing stability. i) ii) iii) iv) Sketch the corresponding power-angle curve for the system showing the accelerating and decelerating areas. Calculate the critical clearing angle of the system to keep its stability.
Q3: - A three-phase fault occurs at bus-1 of the network shown in figure below. The pre-fault voltage is 1.05 PU and the pre-fault load current is neglected. (45%) i) determine the bus impedance matrix. ii) calculate the sub-transient fault current and the contribution to the fault current from the transmission line. T1 T2 T.L j0.1 PU 10.1 PU j0.105 PU G jXdg j0.15 PU M jXdm $0.2 PU
The severity of line-to-ground and 3-phase faults at the terminals of an unloaded star connected synchronous generator is to be same. If the terminal voltage is 1 p.u. and X, = X2 = j0.35 p.u., Xgo = j0.05 p.u., for the alternator, then the required inductive reactance for neutral grounding is (a) X = j0.1 p.u. (b) Xn =j0.015 p.u. (c) Xạ =j0.15 p.u (d) Xn =j02 p.u.
The one-line diagram of a simple three- bus power system is shown below. Each generator is represented by an emf behind the transient reactance. All impedances are expressed in per unit on a common 100 MVA base. Determine the fault current during a fault when a balanced three-phase fault occurs on Bus 1. Use the Thevenin Theorem approach. j0.2 Hint j0.1 J0.8 j0.2 RRRR. R RRR j0.4 j0.4,5 RR. R RRRR. R.RRRRR RRR 2.84xj p.u. 6.25xj p.u. -4.58xj p.u. -6.25xj p.u. 5.10xj p.u.
Figure shows a generator connected to a metropolitan system (infinite bus) through highvoltage lines. The numbers on the figure indicate the reactances in p.u. Breakers adjacent to afault on both sides are arranged to clear simultaneously. Determine the critical clearing anglefor the generator for a 3-phase fault at the point P when the generator is delivering 1.0 p.u.power. Assume that the voltage behind transient reactance is 1.2 p.u. for the generator andthat the voltage at the infinite bus is 1.0 p.u.
b) A fault occurs at bus 2 of the network shown in Figure Q3. Pre-fault nodal voltages throughout the network are of 1 p.u. and the impedance of the electric arc is neglected. Sequence impedance parameters of the generator, transmission lines, and transformer are given in Figure Q3, where X and Y are the last two digits of your student number. JX20 /0.1X p.u. jXa2) 0.1X p.u. JX20 j0.2Y p.u. V,= 120° p.u. V, 120° p.u. V, 120° p.u. jX4-70.2X p.u. jX2 j0.2X p.u. jX o 0.2Y p.u. jXncay J0.25 p.u. jXna J0.25 p.u. 3 jXno0.3 p.u. jXTu) /0.2Y p.u. jXra j0.2Y p.u. - j0.2Y p.u. Xp-10.1X p.u. jXa j0.1X p.u. jXp0)- j0.05 p.u. 0 Figure Q3. Circuit for problem 3b). For example, if your student number is c1700123, then: jXac1) = j0.22 p.u., jXac2) = j0.22 p.u., and jXaco) = j0.23 p. u. X-2 Y=8 (iv) Determine the short-circuit fault current for the case when a phase-to- phase fault occurs at bus 2.
estion 9 The fault current level of a circuit breaker used in a transmission line with phase voltage 2.2 kV and breaking capacity 50 MVA is yet ......kA. vered -ked out of Flag question estion 10 The voltage between lines in a transmission line is the maximum value of the sine waveform. yet vered Select one: -ked out of O True Flag question O False
ns. or A 25 MVA, 13.2 KV, alternator with solidly grounded neutral has a sub transient reactance of 0.025 p.u. The negative and zero sequence reactances are 0.35 and 0.1p.u. respectively. A single line to ground fault occurs at the terminals of an unloaded alternator; Determine the fault current and the line-to-line voltages. Neglect resistance. iont ctability
A 15,000 KVA, 6.9 KV generator, star connected has positive, negative and zero sequence reactances of 0.25, 0.25 and 0.08 p.u. respectively. A reactor of 0.06 p.u. reactance on the generator rating is placed in the line from neutral to ground: A double line to ground fault occurs at the terminals of the generator when it is operating at its rated voltage and unloaded. Find the unitial r.m.s. line and ground wire current for a solidly grounded fault, and also the voltage to ground of the unfaulted line. (UPSC-1975) Ans: 1-1,-4970 A; I, 5480 A; V. 69.7 KV