PSA Past Year University Questions of Unit-3

2018-19

1. Classify and explain the various types of buses of a power system used in power flow analysis?
2. What are the advantages of Ybus over Zbus?
3. Develop and explain the load flow equation by Gauss Method.
4. What is infinite bus?
5. Form Ybus for 4-bus system. If the line series impedances are as follows: Line (bus to bus) Impedance

1 – 2      0.13 + j 0.4 pu

1 – 3      0.1 + j 0.6 pu

1 – 4     0.15 + j 0.5 pu

2 – 3     0.05 + j 0.2 pu

3 – 4    0.06 + j 0.3 pu
Neglect shunts capacitance of line.

2017-18

1. Explain the matrix partitioning in load flow study.
2. Develop ZBus matrix for the network shown in figure
3. Define Load bus, Generator bus and Slack bus.
4. Explain clearly the computational procedure for load flow solution using NewtonRaphson method when the system contains only PQ buses.
5. Discuss the fast decoupled load flow method in load flow study.
6. In the 3 bus system shown in figure the series and shunt impedances of line (L1) is (14.3+j97) ohm and (-j3274) ohm, line (L2) is (7.13+j48.60) ohm and (-j6547) ohm,and line (L3) is (9.38+j64) ohm and (-j4976) ohm respectively, find [YBus].

2016-17

1. What is the necessity of load flow study in a power system? What is Newton-Raphson method? How it is applied for the solution of power flow equation? Explain with the help of an example.

2015-16

1. State Gauss-Seidel load flow formula.
2. Mention the quantites specified and not specified at the reference bus defined for load flow study.
3. Mention the quantites specified and not specified at the reference bus defined for load flow study.
4. Develop the rmthematical model for the load flow analysis of a power slatem using Gauss-Seidal method and discuss its solution algorithm.
5. A 3-bus slatem is shown in figure-2 given below. The series impedance and shunt admittance of each line are (0.01 97 + I 0.0788) PU and j0.04 pu respectively. The bus specification and power input etc. at the buses are given in the table.