Protection against Overvoltages due to Lightning Interview Questions:

Following are the below Protection against Overvoltages due to Lightning Interview Questions and Important Questions which is very useful for interviews and exams

1. What are the causes of overvoltages in power systems ? Discuss. Bring out the functions of ground wire in transmission lines.

2. Discuss the phenomenon of lightning stroke. How can wave set up by such a stroke be represented ?

3. What is a voltage surge ? Draw a typical standard lightning voltage surge ?

4.  How are travelling waves produced in a transmission line ?

5. Explain earth wire protection scheme of transmission line.

6. What is the importance of a ground wire in protecting power conductors against direct lightning stroke? Discuss how these are achieved in practice.

7.  What is a horn-gap arrester ? Explain how its works. What is the purpose of inserting a resistance between horn-gap arrester and the line ?

8. What are the causes of overvoltages and travelling waves in transmission lines ? Explain. Explain with neat diagrams different types of lightning arresters.

9. Describe the construction, principle of operation and application of (i) rod gaps (ii) expulsion gap, (iii) valve type lightning arresters.

10. What are the causes of dangerously high overvoltages on the transmission system ? Give their relative magnitudes.

11. What are the means adopted to protect the power system against such overvoltages ?

12. Describe the construction of a valve type lightning arrester and distinguish between station, line and distribution type lightning arresters.

13. State the various causes of overvoltage in a power system ? Name the various devices used for protection against overvoltage due to lightning.

14. Explain the working principle of thyrite arrester with the help of a neat sketch.

15. Draw neat labelled diagrams, of the following types of lightning arresters. (i) Rod gap (ii) Horn gap (iii) Multi-gap (iv) Expulsion type (v) Thyrite type.

16. Explain the working of different types of lightning arresters with particular reference to ‘Spark-gap’, `Thyrite’, and ‘Horn-gap’ types.

17. What is impulse ratio and coupling factor and how are these utilised in the design of transmission line against lightning ?

18. Describe the construction and explain the operation of thyrite type lightning arrester and explain for what part of the circuit it would be most satisfactory.

19. Explain clearly why lightning arresters are used. Describe any type of oxide film arresters with a neat sketch, explaining underlying features. Name other types of lightning arresters used nowadays in protecting equipment and overhead line.

20. Explain how a substation and the equipment in the substation are protected from lightning strokes.

21. What are surge absorbers and how do they differ from surge diverters ?

22. Explain how surge absorbers provide protection to equipments from destructive effects of travelling waves.

23. Give an idea about lightning voltages and currents that occur in power system. Hence sketch typical voltage wave and explain it.

24. What is the function of a surge absorber ? In what way is it different from lightning arrester ?

25. What are the requirements of a lightning arrester ?

26. Differentiate between (i) a lightning arrester and a lightning conductor. (ii) a surge diverter and a surge absorber.

27. Write short notes on the following:

• Causes of overvoltages in a power system.
• Switching surges.
• Lightning phenomenon and its effects on transmission lines.
• Protection against overvoltages.
• Lightning arresters.
• Lightning arresters and their uses.
• Thyrite arrester.
• Surge absorbers.
• Location, working principle and rating of lightning arrester.
• ERA surge filter.