According to the propagation mode, lightning can be divided into direct lightning and inductive lightning. Lightning is a discharge phenomenon in the atmosphere. It is mostly formed in cumulonimbus clouds. Cumulonimbus clouds will keep moving with the change of temperature and air flow. Friction generates electricity in the movement, forming charged clouds.
Direct lightning strike is a rapid discharge phenomenon between charged clouds (Thunder clouds) and buildings, other objects, the earth or lightning protection devices, and a series of destructive effects such as electrical effect, thermal effect or mechanical force.
Induced lightning is also known as lightning induction or induced overvoltage. It is divided into electrostatic induction mine and electromagnetic induction mine. Electrostatic induction lightning is caused by a large amount of charge induced on the top of overhead line conductor or other conductive protrusions when charged cumulus is close to the ground. Electromagnetic induction lightning is caused by the rapid change of strong magnetic field in the surrounding space caused by huge impulse lightning current during lightning discharge.