High Voltage Engineering — Summer 2019

Explain streamer theory of breakdown in gases.

Describe, with a neat sketch the working of a Van de Graff generator.

Explain the working of Cockcroft – Walton circuit with schematic diagram.

What is Partial discharge of solid insulating material? Explain in detail.

What is Paschen’s law? Explain significance of existence of minimum sparking potential in paschen’s curve.

Discuss Marx circuit for multistage impulse generator with necessary circuit diagram

Explain test facilities and testing equipments in high voltage Laboratories

Explain how a sphere gap can be used to measure the peak value of voltages. What are the parameters and factors that influence such voltage measurement?

Explain thermal breakdown in solid dielectrics. How this mechanism is more significant than the other mechanisms?

Explain the insulation testing of insulators.

Discuss high voltage Schering bridge.

What are “Treeing” and “Tracking”? Explain clearly the two processes in solid dielectrics.

Explain the different electrical tests carried out on isolators and circuit breakers.

Explain with neat sketches the mechanism of lightning discharge.

Explain corona Discharges.

Explain with neat diagram the principle of operation of an electrostatic voltmeter. Discuss its advantages and limitations for high voltage measurement.

What is meant by insulation co-ordination? How are the protective devices chosen for optimal insulation level in a power system?