The document discusses corona discharges as electrical discharges occurring around charged conductors due to gas ionization. It highlights the conditions under which corona discharges occur, particularly in high electric field areas like sharp points on transmission lines. Additionally, it notes the byproducts of corona discharges, including gases like ozone and nitric oxide.

1. HIGH VOLTAGE
ENGINEERING
CORONA
DISCHARGES
IN SIMPLE
LAUNGUAGE
LEC # 09
BREAKDOWN
IN GASES

2. CORONA DISCHARGES
 Corona Discharge an electrical
discharge appearing on and around
the surface of a charged conductor,
caused by ionization of the
surrounding gas
 If the field is non-uniform, an increase in
voltage will first cause a discharge in the
gas to appear at points with highest
electric field intensity, namely at
sharp points or where the electrodes
are curved or on transmission lines.
Corona discharge on a 500
kV overhead power line

3. DISCHARGE
TAKES PLACE
ELECTRIC FIRLD
INCREASES
SPACE CHARGE
IONISED
HOW CORONA DISCHARGE TAKES PLACE ?
CORONA
DISCHARGE
MORE FREE
IONS FORM

4. CORONA DISCHARGES

5. CORONA DISCHARGES

6. PROPERTIES OF CORONA DISCHARGES
 In the air, coronas generate gases such
as ozone (O3) and nitric oxide (NO),
and in turn, nitrogen dioxide (NO2), and
thus nitric acid (HNO3) if water vapor is
present.
 This form of discharge is called a
CORONA DISCHARGE and can be
observed as a bluish luminescence
The corona discharge
around a high-voltage coil