HIGH VOLTAGE ENGINEERING - EXPECTED UNIVERSITY QN

EE 2353 HIGH VOLTAGE ENGINEERING

IMPORTANT QUESTIONS

Unit - I

1.      Draw the cross sectional view of non linear resistor lightning arrester (valve type) and explain its operation in detail and its V-I characteristics.

2.      Discuss mechanism of lightning stroke and over voltages on transmission lines and give its mathematical model.

3.      Explain Townsend’s first and second ionization process and derive the equation.

4.      Explain different theories of charge formation in clouds.

5.      What are the methods to control over voltages?

Unit - II

1.      State the criteria for sparking potential and hence obtain the relation between sparking potential and (PD) values (Paschens law). Discuss nature of variation of sparking potential with PD values.

2. Explain breakdown mechanism on solid dielectric.

3. Explain breakdown mechanism on vacuum dielectric.

4. Explain breakdown in non uniform fields and corona discharge.

Unit - III

1. Starting from basic marx circuit develop the circuit of modern multistage impulse generator and explain its operation. Discuss significance of various parameters.

2. Explain vandegraff generator.

3. Explain cascade transformer connections and resonant transformer.

Unit - IV

1. Explain measurements of very high voltages using sphere gaps. Mention merits and de merits of using sphere gaps.

2. Explain electro static voltmeter for HVAC measurements. Give its advantages and     disadvantages.

3. Explain generating voltmeter for measuring high DC voltage.

4. Explain Capacitance voltage transformer.

5. Explain hall generator.

Unit -V

1.      Explain testing of transformer.

2.      Explain testing of insulator.

3.      Explain testing of isolators and circuit breakers.