OBJECTIVE: To learn the methods of high voltage and current generation and their measurement and high voltage testing procedures.
Causes & types of over voltages - Lightning, switching, temporary overvoltages - Effects of overvoltages on power system components - EMI and EMC protection against overvoltages - Surge diverters - Insulation co-ordination.
Generation of high AC and DC, impulse and switching voltages - Generation of high impulse currents.
Measurement of high AC, DC, impulse and switching voltages using sphere gaps, peak voltmeters, potential dividers, high speed CRO and digital techniques - Measurement of high currents.
Self and non self restoring insulation - Breakdown in gases, liquids and solids - Breakdown in uniform and non-uniform fields - partial discharges - Corona.
Staandards and specifications - Types of tests - Testing and fault diagnostics - Testing of circuit breakers, isolators and air switches - Testing of insulators, bushing and surge diverters.