For the three-bus system shown in figure below: • The line from bus 1 to bus 2 has an imped- ance Z = 0.05+j0.1 The other two line (1-3 and 2-3) both have an impedance Z = j0.25 The load at bus 3 is consuming 150 MW and 87 Mvar wwwwww The generator at bus 1 has a voltage set- point of 1.03 per-unit о Bus 1 Bus 2 4-j12 -4+j8j4 Ybus = -4+j8 4j12 j4 j4 j4 -j8. Bus 3 Given the Y-bus above, with bus 1 as slack bus and buses 2 and 3 as PQ buses, write the real and reactive power balance equations for bus 3 only, in terms of 02, 03, V2 and V3. You do not need to find the Jacobian or solve the equations. Include the load P and Q.

For the three-bus system shown in figure below: • The line from bus 1 to bus 2 has an imped- ance Z = 0.05+j0.1 The other two line (1-3 and 2-3) both have an impedance Z = j0.25 The load at bus 3 is consuming 150 MW and 87 Mvar wwwwww The generator at bus 1 has a voltage set- point of 1.03 per-unit о Bus 1 Bus 2 4-j12 -4+j8j4 Ybus = -4+j8 4j12 j4 j4 j4 -j8. Bus 3 Given the Y-bus above, with bus 1 as slack bus and buses 2 and 3 as PQ buses, write the real and reactive power balance equations for bus 3 only, in terms of 02, 03, V2 and V3. You do not need to find the Jacobian or solve the equations. Include the load P and Q.

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

Chapter7: Symmetrical Faults

Section: Chapter Questions

Problem 7.14P: Equipment ratings for the five-bus power system shown in Figure 7.15 are as follows: Generator G1:Â...

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Figure below shows a power system where load at bus 5 is fed by generators at bus 1 and bus 4. The generators are rated at 100MVA; 11 KV with subtransient reactance of 25%. The transformers are rated each at 100 MVA, 11/112 KV and have a leakage reactance of 8%. The lines have an inductance of 1 mH/phase/km. Line L1 is 100 km long while lines L2 and L3 are each of 50 km in length. 1- For a 3-phase fault at bus 5, the fault current is equal to 2530A. What the value of the change in the fault current if the value of the base voltage is changed to 10 kV (i.e. new value/old value). 2- For a 3-phase fault at bus 5, the fault current is equal to 2530A. What the value of the change in the fault current if the length of L1 is reduced to 50 km (i.e. new value/old value).
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The figure below shows the one-line diagram of a four- bus power system. The voltages, the scheduled real power and reactive powers, and the reactances of transmission lines are marked at this one line diagram (The voltages and reactances are in PU referred to 100 MW base. The active power P2 in MW is the last three digits (from right) of your registration number (i.e for the student that has a registration number 202112396, P2 =396). [10] Starting from an estimated voltage at bus 2, bus 3, and bus 4 equals V2 (0) = 1.15<0°, V3 = 1.15 < 0°, V4 1.1< 0°. 1- Specify the type of each bus and known & unknown quantities at each bus. 2- Find the elements of the second row of the admittance matrix (i.e. [Y21 Y22 Y23 Y24]). 3- Using Gauss-Siedal fınd the voltage at bus 2 after the first iteration. 4- Using Newton-Raphson, calculate: |- The value of real power (P2), at bus 2 after the first iteration. Il- The second element in the first row of the Jacobian matrix after the first iteration. 2 P2…
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Figure below shows one-line diagram of a simple three bus power system with generation at bus 1. Bus 1 is considered as slack bus. A load consisting of 250 MW and 110 MVAR is taken from bus 2. A load consisting of 128 MW and 35 MVAR is taken from bus 3. Line impedances are marked in per unit on a 100 MVA base. Line susceptances are neglected. G1 0.01 +10.03 V₁ = 1.040° 0.02 +0.04 Select one: O a. None of these O b. 0.9245-j0.025 O c. 0.9245+j0.025 O d. -0.9245-j0.025 e. 0.9638-j0.03 0.0125+j0.025 ·0 P2 Q2 P3 Q3 Start with flat initial estimates of ₂0) = 1 + j0 & V3⁰) = 1 + j0, and keeping |V₂| = 1 pu, find V₂(¹)