HIGH VOLTAGE ENGINEERING
EE-704A
Credit: 3
Breakdown phenomena:
Breakdown of Gases: Mechanism of Break down of gases, Charge multiplication, Secondary
emission, Townsend Theory, Streamer Theory, Paschen’s Law, Determination of Minimum
breakdown voltage, Breakdown in non uniform field, Effect of polarity on corona inception
and break down voltage.
Partial Discharge: definition and development in solid dielectric.
Break Down of Solids: Intrinsic breakdown, Electromechanical break down, Thermal
breakdown, Streamer Breakdown.
Breakdown of Liquid: Intrinsic Break down, Cavitation Theory, Suspended particle Theory.
Breakdown in Vacuum: Non metallic electron emission mechanism, Clump mechanism,
Effect of pressure on breakdown voltage.
Generation of High Voltage:
Generation of high AC voltages: Testing transformer, Cascaded transformer, Series resonant
circuit, single stage and multi stage. Advantages of Series Resonant Circuit in testing of
cables.
Generation of DC high voltage: Cockcroft Walton doubler and multistage circuit.
Electrostatic generator.
Definition of Impulse Voltage as per Indian Standard Specification, Wave front and wave tail
time ,Generation of Impulse Voltage, Multistage
Impulse generator, triggering of Impulse Generator.
Measurement of High Voltage:
Sphere gap voltmeter, AC , DC and impulse high voltage measurement as per Indian Standard
Specifications. Resistance and Capacitance Potential dividers, Peak voltmeters for measurement
of high AC voltage in conjunction with capacitance dividers. Capacitance Voltage Transformer,
Rotating Voltmeter for the measurement of DC high voltage, Electrostatic Voltmeter
Transient in power systems:
Lightning Phenomena, Electrification of cloud, Development of Lightning Stroke, lightning
induced over voltage, direct stroke, indirect stroke.
Protection of Electrical Apparatus against over voltage, Lightning Arrestors, Valve Type,
Metal Oxide arresters, Expulsion type. Effect of location of lightning arresters on protection
of transformer. Protection of substation, Ground wires.
Insulation Co ordination, Basic Insulation level. Basic Impulse level, Switching Impulse
level. Volt time characteristics of protective devices, Determination of Basic Impulse level of
substation equipment.
5
High Voltage Testing:
High Voltage testing, Testing as per Indian Standard Specifications, Power frequency
04
withstand, induced over voltage and impulse test on transformers, Power frequency wet
withstand test and impulse test on insulators
Numerical problems to be solved in the class.
Text Books:
1. High Voltage Engineering, C.L. Wadhawa, New Age International Publishers.
2. High Voltage Engineering, M.S. Naidu & V. Kamraju, Tata MC Graw Hill publication.
3. Book of Bgamude.
Reference Books:
1. High Voltage Engineering, M.A. Salem, H. Anis, A. E. Morahedy, R. Radwan, Marcel Dekker, Inc.
