What are the main lightning protection measures?

Lightning protection includes lightning protection of power system and lightning protection of buildings and structures. Lightning protection of power system mainly includes generator lightning protection, power distribution equipment lightning protection and power line lightning protection. Lightning protection of buildings and structures can be divided into two categories: industrial and civil. Industry and civil use are divided into three categories and two categories according to their degree of danger and the importance of facilities. Different types of buildings and structures have different requirements for lightning protection.

Lightning rod, lightning wire, lightning protection network, lightning protection belt and lightning arrester are all commonly used lightning protection devices. A complete lightning protection device includes lightning receptor, down conductor and grounding device. The needles, wires, nets and belts on it are all lightning receptors. Lightning arrester is a special lightning protection equipment.

lightning conductor

Installing lightning rod is an effective method to prevent direct lightning. Lightning rods can be used to protect open-air distribution devices and power lines, as well as buildings and structures. As far as its essence is concerned, lightning rod is not lightning protection, but uses its advantage of standing high in the air to lead lightning to itself, bear lightning strike, and drain lightning current into the earth, thus protecting other equipment from lightning strike.

earth wire

The function of lightning rod is similar to that of lightning rod. It is a metal wire erected at the top of the tower along the line and well grounded. It is mainly used to protect the power cord. At this time the lightning rod is also called overhead ground wire. Lightning wires can also be used to protect long and narrow facilities.

Lightning protection network and lightning protection zone

Lightning protection network and lightning protection belt are mainly used for preventing direct lightning in industrial and civil buildings, and also as safety measures for electrostatic induction. It is a metal grid laid along the corners, roofs, cornices, eaves and other parts of buildings that are vulnerable to lightning.

lightning arrester

Lightning arrester can be divided into valve arrester, tube arrester and protective gap. Mainly used to protect power equipment, but also as a safety measure to prevent lightning waves from invading the room.

Valve arrester is the most important basic component to protect power generation and transformation equipment, which is mainly composed of discharge gap and nonlinear resistance. When the lightning wave with high amplitude invades the protected equipment, the gap of the arrester discharges first, thus limiting the overvoltage value on the insulation equipment and playing a protective role.

The structure of tube arrester and protective gap is relatively simple, and the protective performance is not as good as that of valve arrester, so it can be used in places with low requirements or as auxiliary lightning protection measures.

Tube arrester is essentially a kind of protective gap with arc extinguishing ability. When the lightning wave invades the discharge grounding, the power frequency arc can be quickly blown out without opening the arc through the action of the circuit breaker, thus ensuring the continuity of power supply.

Protective gap is a simple and effective overvoltage protection element, which consists of two electrodes, charged and grounded, with a certain gap distance between them. It is connected in parallel with the protected equipment. When the lightning wave strikes, the gap first breaks down, introducing similar current into the earth, thus avoiding the protected equipment from being damaged by high-amplitude overvoltage.

Ionization lightning protection

Ionization lightning protection is a new technology. It consists of ionization device at the top, underground current collection device and connecting wire.

The ionization lightning protection device does not prevent lightning accidents by controlling the lightning strike point, but uses Lei Yun's induction, or uses radioactive elements to form a strong electric field near the ionization device, which ionizes the air and produces ion flow moving to Lei Yun. In this way, the charge carried by Lei Yun can be neutralized and slowly leaked, so that the electric field strength in space does not exceed the breakdown strength of air, the lightning falling condition is eliminated, and the occurrence of lightning strike is suppressed.