High Voltage Engineering 2012 Important Questions

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Anna University
High Voltage Engineering 2012 Important Questions


Subject Code : EE2353

Subject Name : High Voltage Engineering


Unit I

1. Discuss the various types of protective devices used in transmission lines.
2. Explain the different methods employed for lightning protection of overhead lines.
3. Explain the mechanism of lightning strokes inducing high over voltages on transmission lines
4. Explain the causes for power frequency over voltages in power systems.

Unit II

1. What are the factors that influence conduction in pure liquid dielectrics and in commercial liquid dielectrics?
2. Describe the mechanism of short term breakdown of composite insulation.
3. Derive an expression for the growth of current growth due to Townsend’s primary ionization.
4. Discuss the current growth phenomenon in a gas subjected to uniform and non-uniform fields
5. State why the very intrinsic strength of solid dielectric is not fully realized in practice. Explain in detail any one mechanism of breakdown in solid dielectrics.

Unit III

1. Explain the different schemes of transformer connection for producing very high AC voltages.
2. Explain the Marx circuit arrangement for multistage impulse generators. How is the basic arrangements modified to accommodate the wave time control.
3. Discuss the principle of operation of Vande graaff Generator with neat diagram
4. Explain the tripping and control of impulse generators.

Unit IV

1. What are the different types of resistive shunts used for impulse current measurements? Discuss their characteristics and limitations
2. explain the sphere gap arrangement method of high voltage measurement and give the factors influencing the measurement with neat diagram
3. explain the methods used for the measurement of high voltages and high currents
4. Explain the principle and construction of an electrostatic voltmeter for very high voltages

Unit V

1. Draw the cross sectional view of a non-linear resistor lightning arrester and explain its operation
2. Explain the insulation coordination in EHV and UHV systems
3. Explain the power frequency, impulse voltage and thermal test conducted on bushings.
4. Discuss the dielectric power factor test and partial discharge test conducted on high voltage cables