What is corona discharge?

An electrical discharge known as a corona discharge results from the ionization of a fluid, such as the air around an electrically charged conductor. High-voltage systems naturally experience spontaneous corona discharges unless the electric field intensity is carefully controlled. A corona will emerge when the electric field (potential gradient) intensity surrounding a conductor is strong enough to create a conductive zone but not so strong as to damage neighboring items with electrical breakdown or arcing. It generates light similarly to a gas discharge lamp and is frequently observed as a blue (or other hue) glow in the area around pointed metal conductors carrying high voltages. Corona is an unwelcome side effect in plenty of high voltage applications.