What is silent corona discharge?
A corona discharge is an electrical discharge caused by the ionization of a fluid such as air surrounding a conductor carrying a high voltage. A corona occurs at locations where the strength of the electric field (potential gradient) around a conductor exceeds the dielectric strength of the air.
What are the effects of corona discharge?
Corona discharge can cause an audible hissing or cracking noise as it ionizes the air around the conductors. This is common in high voltage electric power transmission lines. The corona effect can also produce a violet glow, production of ozone gas around the conductor, radio interference, and electrical power loss.
Why is corona discharge purple?
The bluish-purple glow that corona discharges produce is a side effect of electrons recombining with positive ions to reform neutral atoms. When atoms reform they release a photon of light. These photons ionize more atoms maintaining the corona discharge. Corona discharges are a non-thermal, non-equilibrium product.
Where does corona discharge occur?
Corona discharge takes place at atmospheric pressure in contrast to low temperature (or cold) plasma that requires vacuum. Corona is a stream of charged particles such as electrons and ions that is accelerated by an electric field.
What is corona in transmission?
Definition: The phenomenon of ionisation of surrounding air around the conductor due to which luminous glow with hissing noise is rise is known as the corona effect. Air acts as a dielectric medium between the transmission lines. In other words, it is an insulator between the current carrying conductors.
How can the corona effect be reduced PDF?
Corona discharge can be reduced by the following methods:
- By increasing the conductor size: As explained above, larger the diameter of the conductor, lesser the corona discharge.
- By increasing the distance between conductors: Larger the conductor spacing, lesser the corona.