HIGH VOLTAGE ENGINEERING JNTU previous years question papers

HIGH VOLTAGE ENGINEERING JNTU previous years question papers

Time: 3 hours Max Marks: 80

Answer any FIVE Questions

All Questions carry equal marks

1. (a) Define field factor. How does it vary with simple geometries?
(b) Classify the electric field and give the example for each one. [8+8]

2. (a) What are commercial liquid dielectrics? How are they different from pure liquids.
(b) Discuss about the electronic breakdown mechanism in commercial liquids.
[8+8]

3. (a) Explain the properties and applications of Fibre solid dielectric materials used in practice in the high voltage engineering.
(b) Explain about the avalanche breakdown in solid dielectric material. [8+8]

4. (a) Draw a typical impulse current generator circuit and explain its operation and application.
(b) A 12-Stage impulse generator has capacitors each rated at 0.3 µF, 150 kV. The capacitance of the test specimen is 400 pF. Find the wave front and wave tail Resistances to produce a 1.2/50µs impulse wave. Also determine the maximum output voltage if the charging voltage is 125 kV [8+8]

5. Discuss the different methods of measuring high DC voltages. What are the limitations in each method? [16]

6. Give the mathematical models for lightning discharges and explain them. [16]

7. Explain the concept of apparent charge in partial discharge measurements. Describe a simple experiment technique to measure partial discharge [16]

8. Explain the procedure for testing string insulator?

FEEL USEFUL PLEASE GIVE +1