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.
Q: Figure 2 shows the circuit of a simple power system. The ratings of the generators, transformers and…
A: We are authorized to answer three subparts at a time, since you have not mentioned which part you…
Q: Three zones of a single-phase circuit are identified in Figure. The zones are connected by…
A: per unit system The ratio of actual value to the base or reference value in the same unit is called…
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Q: Q1/ Equipment ratings for the four-bus power system shown in Figure are as follows: Generator G1:…
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Q: 1- Draw the zero-, positive-, and negative-sequence reactance diagrams using a 1000-MVA, 20-kV base…
A: Thevenin Theorem is highly useful for assessing power systems and other circuits where one specific…
Q: Line to line to line fault is an asymmetrical type of fault in power system which occurs very…
A: Given Line to line fault is an asymmetrical type of fault in power system.
Q: The following figure shows the single-line diagram of a three-bus power system. Additionally, a…
A: y23=-j20-j25 =-j45 If three phase fault occurs at bus 3
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A: We can redraw the per-phase equivalent circuit as
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Q: Q2/K/ The positive-sequence reactances for the power system shown in Figure are in per unit on a…
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Q: Problem 6 a- Explain the reasons for applying system grounding in electric power systems. Consider…
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Q: 5. The positive sequence network, negative sequence network and zero sequence network are shown in…
A: It is given that: Zf=0.05
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Q: The magnitude of the fault current depends on the generator and fault impedance and ________________…
A: The magnitude of fault current depends on voltage at fault point and impedance upto fault point…
Q: 96\ Derive equations of critical clearing angle and time for a symmetrical three-phase fault at…
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Q: For the circuit shown, if a symmetrical three-phase fault occurs in node 2, determine a. The…
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Q: For grounded systems, the _ for the service and the system bonding jumper for separately derived…
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Q: three phase generator with constant terminal voltages gives the following currents when under fault:…
A: The solution can be achieved as follows.
Q: Problem 5: Thevenin equivalent sequence networks looking into the faulted bus of a power system are…
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Q: Q1. Given Z, = 0.3L60º, Z¡ = 0.17L80° and, Z2 = 0.45L120°. Compute the fault current and voltages…
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Q: 1. Consider a single-phase 11 KV/0.11 kV 1.1 MVA transformer protected by percentage differential…
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Q: Q2/The positive-sequence reactances for the power system shown in Figure are in per unit on a common…
A: Current: It is the time rate of the change of the charges. It is also known as the flow of the…
Q: V, =1.025Z0°pu P=300MW j0.05 Bus 1 Bus 3 V = 1.03 Slack j0.025 j0.025 Bus 2 400MW 200MVAR
A: The given power system can be redrawn as shown below:
Q: The one line diagram of a simple three bus power system is shown in figure Each generator is…
A: The fault occurred on bus 3 is a three phase fault. Three phase fault is a balanced fault (All…
Q: The one-line diagram of a simple power system is shown in the figure. The neutral of each generator…
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Q: For the system shown in figure Q5. а. Determine the three-phase fault power (in MVA) and the short…
A: Base MVA= 20MVA Per unit reactance of all the generators: Per unit reactance of transformers:
Q: 2) Draw equivalent diagram for this network with all per unit resistances and reactance near their…
A: The detection and diagnosis of faults in technical systems, particularly using a strategy in which…
Q: Question 2: A single-line diagram of the power system is shown in Figure 2, where negative- and…
A: Since you have posted a question with multiple sub-parts, we will solve the first three sub-parts…
Q: Figure 2 shows the circuit of a simple power system. The ratings of the generators, transformers and…
A: Base MVA =150MVA Base Kv=13.8kV Xnewpu=Xold×MVAnewMVAold×KvoldKvnew2…
Q: 3) The single-line diagram of a three-phase system is given in Figure 3. The three-phase generator…
A: Since you have asked multiple questions in a single request, we will be answering only the first…
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Q: Q2/The positive-sequence reactances for the power system shown in Figure are in per unit on a common…
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Q: 1. A three-phase short-circuit fault occurs at point F in the system shown. Calculate the p.u. fault…
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Q: Suppose V-1.0°p.u., z= j0.50 p.u., z z-jo.25 p.u.; draw a sequence network cannection in case of…
A: When there is no fault impedance present in between fault points then it is called bolted fault…
Q: Given the network shown, for a solid three-phase fault on bus 2 (a) find the sub transient current…
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Q: The positive sequence reactance for the power system shown in Figure below are in per unit on a…
A: Given: The positive sequence reactance for the power system shown in the Figure below is per unit on…
Q: All Choose the correct answer: 1. One of the advantage of using a per unit system in power system…
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Q: Q9: The reactance data for the power system shown in Figure below in per unit on a common base is as…
A: As per the guidelines of Bartley we supposed to answer first three subpart only for solution of…
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- Consider the oneline diagram shown in Figure 3.40. The three-phase transformer bank is made up of three identical single-phase transformers, each specified by X1=0.24 (on the low-voltage side), negligible resistance and magnetizing current, and turns ratio =N2/N1=10. The transformer bank is delivering 100 MW at 0.8 p.f. lagging to a substation bus whose voltage is 230 kV. (a) Determine the primary current magnitude, primary voltage (line-to-line) magnitude, and the three-phase complex power supplied by the generator. Choose the line-to-neutral voltage at the bus, Va as the reference Account for the phase shift, and assume positive-sequence operation. (b) Find the phase shift between the primary and secondary voltages.Consider a single-phase electric system shown in Figure 3.33. Transformers are rated as follows: XY15MVA,13.8/138kV, leakage reactance 10 YZ15MVA,138/69kV, leakage reactance 8 With the base in circuit Y chosen as 15MVA,138kV determine the per-unit impedance of the 500 resistive load in circuit Z, referred to circuits Z, Y, and X. Neglecting magnetizing currents, transformer resistances, and line impedances, draw the impedance diagram in per unit.Three single-phase two-winding transformers, each rated 3kVA,220/110volts,60Hz, with a 0.10 per-unit leakage reactance, are connected as a three-phase extended autotransformer bank, as shown in Figure 3.36(c). The low-voltage winding has a 110 volt rating. (a) Draw the positive-sequence phasor diagram and show that the high-voltage winding has a 479.5 volt rating. (b) A three-phase load connected to the low-voltage terminals absorbs 6 kW at 110 volts and at 0.8 power factor lagging. Draw the per-unit impedance diagram and calculate the voltage and current at the high-voltage terminals. Assume positive-sequence operation.
- The per-unit equivalent circuit of two transformers Ta and Tb connected in parallel, with the same nominal voltage ratio and the same reactan of 0.1 per unit on the same base, is shown in Figure 3.43. Transformer Tb has a voltage-magnitude step-up toward the load of 1.05 times that of Ta (that is, the tap on the secondary winding of Tb is set to 1.05). The load is represented by 0.8+j0.6 per unit at a voltage V2=1.0/0 per unit. Determine the complex power in per unit transmitted to the load through each transformer, comment on how the transformers share the real and reactive powers.With the same transformer banks as in Problem 3.47, Figure 3.41 shows the oneline diagram of a generator, a step-up transformer bank, a transmission line, a stepown transformer bank, and an impedan load. The generator terminal voltage is 15 kV (line-to-line). (a) Draw the per-phase equivalent circuit, aounting for phase shifts for positive-sequence operation. (b) By choosing the line-to-neutral generator terminal voltage as the reference, determine the magnitudes of the generator current, transmiss ion-line current, load current, and line-to-line load voltage. Also, find the three-phase complex power delivered to the load.PowerWorid Simulator case Problem 3_60 duplicates Example 3.13 except that a resistance term of 0.06 per unit has been added to the transformer and 0.05 per unit to the transmission line. Since the system is no longer lossless, a field showing the real power losses has also been added to the oneline. With the LTC tap fixed at 1.05, plot the real power losses as the phase shift angle is varied from 10 to +10 degrees. What value of phase shift minimizes the system losses?
- Three single-phase, two-winding transformers, each rated 450MVA,20kV/288.7kV, with leakage reactance Xeq=0.10perunit, are connected to form a three-phase bank. The high-voltage windings are connected in Y with a solidly grounded neutral. Draw the per-unit equivalent circuit if the low-voltage windings are connected (a) in with American standard phase shift or (b) in Y with an open neutral. Use the transformer ratings as base quantities. Winding resistances and exciting current are neglected.Equipment ratings for the five-bus power system shown in Figure 7.15 are as follows: Generator G1:    50 MVA, 12kV, X=0.2 per unit Generator G2: 100 MVA, 15 kV, X=0.2 per unit Transformer T1: 50 MVA, 10 kV Y/138kVY,X=0.10 per unit Transformer T2: 100 MVA, 15 kV /138kVY,X=0.10 per unit Each 138-kV line: X1=40 A three-phase short circuit occurs at bus 5, where the prefault voltage is 15 kV. Prefault load current is neglected. (a) Draw the positive-sequence reactance diagram in unit on a 100-MVA, 15-kV base in the zone of generator G2. Determine (b) the Thévenin equivalent at the fault, (c) the subtransient fault current in per unit and in kA rms, and (d) contributions to the fault from generator G2 and from transformer T2.Consider the adopted per-unit system for the transformers. Specify true or false for each of the following statements: (a) For the entire power system of concern, the value of Sbase is not the same. (b) The ratio of the voltage bases on either side of a transformer is selected to be the same as the ratio of the transformer voltage ratings. (c) Per-unit impedance remains unchanged when referred from one side of a transformer to the other.
- Consider a bank of this single-phase two-winding transformers whose high-voltage terminals are connected to a three-phase, 13.8-kV feeder. The low-voltage terminals are connected to a three-phase substation load rated 2.0 MVA and 2.5 kV. Determine the required voltage, current, and MVA ratings of both windings of each transformer, when the high-voltage/low- voltage windings are connected (a) Y-, (b) -Y, (c) Y-Y, and (d) -.Three single-phase two-winding transformers, each rated 25MVA,54.2/5.42kV, are connected to form a three-phase Y- bank with a balanced Y-connected resistive load of 0.6 per phase on the low-voltage side. By choosing a base of 75 MVA (three phase) and 94 kV (line-to-line) for the high-voltage side of the transformer bank, specify the base quantities for the low-voltage side. Determine the per-unit resistance of the load on the base for the low-voltage side. Then determine the load resistance RL in ohms referred to the high-voltage side and the per-unit value of this load resistance on the chosen base.Consider three ideal single-phase transformers (with a voltage gain of ) put together as three-phase bank as shown in Figure 3.35. Assuming positive-sequence voltages for Va,Vb, and Vc find Va,Vb, and VC. in terms of Va,Vb, and Vc, respectively. (a) Would such relationships hold for the line voltages as well? (b) Looking into the current relationships, express IaIb and Ic in terms of IaIb and Ic respectively. (C) Let S and S be the per-phase complex power output and input. respectively. Find S in terms of S.