Ever wondered what a corona discharge is? You are not alone. A corona is an energy transfer created by the ionization of a medium, like air, particularly around a high-voltage conductor. It typically forms a localized glowing region of plasma, and is generally shaped like a crown, hence corona. Here are three things to know about Corona discharges.

Corona discharge of the High Voltage transmission line : Looks more like blue lightning in the air.

A corona discharge is a type of electrical discharge that occurs when an electrical field becomes powerful enough to produce a blue like glow discharge. This corona glow is typically associated with high-voltage electrodes, like the tips of tesla coils or lightning bolts from thunderclouds.

A corona is an electrical phenomenon that sometimes appears around the sharp points of high voltage, high current equipment or above powerful radio transmitting antennae.

Corona discharges are mostly an unwanted effect

Corona discharges occur when a voltage is high enough at the surface of an object with a small point. While pretty, coronal glows are a sign of electrical stress and should be investigated to ensure proper functioning of the system and personal safety.

Corona discharges can produce light energy as well as sound. Transmissions lines that carry very high voltages usually produce a small noise due to corona discharges. This can contribute to loss of energy during the transmission. Corona can damage the insulation inside transformers and motors making the equipment more susceptible to damage.

Corona discharges can be minimized by proper forms of insulation as well as changing the shape of the electrodes to a smooth and rounded shape.

Corona discharges can be useful in some occasions

While corona discharges mostly being useless, controlled generation of corona discharges can be used in a variety of fields. Air ionizers, sanitization of pool water and Nitrogen laser equipment use these techniques. Also in photocopy machines, spectrometers and production of ozone gas are done with the utilization of corona discharges.