# Power System Transients EE2027 AM11 6th Semester Question Paper

Question Paper Code : 11306
B.E./B.Tech. DEGREE EXAMINATION, APRIL/MAY 2011
Sixth Semester
Electrical and Electronics Engineering
EE2027 - POWER SYSTEM TRANSIENTS
(Regulation 2008)

PART A — (10 x 2 = 20 marks)

1. Draw the double frequency transient with an example.
2. List the effects of transients on power system.
3. What is meant by Resistance switching?
4. Define ferroresonance.
5. What is called charge formation?
6. Write the formula for tower footing resistance.
7. What are the specifications of a travelling wave?
8. Why velocity of propagation over all overhead lines is same?
9. What is meant by kilometric fault?
10. What are the effects of transients when a switch is closed?

PART B — (5 x 16 = 80 marks)

11. (a) Define Transient. Describe in detail about its importance. (16)
(Or)
(b) What are the broad classifications of power system transients? Describe its different types depending upon its nature. (16)

12. (a) What is known as Load switching? Derive its equivalent circuit.(16)
(Or)
(b) What is called capacitive switching? With necessary sketches, explain capacitive switching with a restrike and multiple restrike. (16)

13. (a) With necessary diagrams, describe the mechanism of lightning discharges and also the characteristics of lightning strokes. (16)
(Or)
(b) (i) What are the factors contributing to good line design in a power system? (8)
(ii) With a neat diagram, explain the protection offered by ground wires. (8)

14. (a) What are called lumped parameters? Explain the transient response of systems with series and shunt lumped parameters. (16)
(Or)
(b) Compare Travelling Waves and Standing Waves. (16)

15. (a) Derive the reflection and transmission coefficient in an integrated power system.
(Or)
(b) Describe in detail about the causes of over voltages induced by various faults occurring in a power system.(16)