As early as the 1950s and 1960s, surge protectors have been widely used in lightning protection design. Surge protectors were first called voltage protectors, but in fact, surge protectors can not only suppress overvoltages, but also It can separate the surge current, so it is not comprehensive to call this kind of lightning arrester simply an over-voltage protector. Therefore, when partial revisions are made to the building lightning protection design standard, it is collectively called a surge protector. With the rapid economic development in recent years and the continuous improvement of the level of science and technology, people's awareness of lightning protection has continued to increase, so that powerful surge protectors have also developed rapidly, and a new industry has gradually formed.
The powerful surge protector is widely used in the lightning protection. The surge protectors can be classified into different types besed on methods. According to the working principles, the protectors can be divided into voltage switch type, voltage limit type and combined type surge protector; according to their use, they can be divided into power line surge protection There are two types of surge protectors and signal line surge protectors; according to the combined structure, they can be divided into gap type, discharge tube type, varistor type, suppressor diode type, varistor/gas discharge tube combination type and silicon carbide type; according to the installation. They can be divided into parallel surge protector and series surge protector based on forms. The common intelligent surge protector against lightning is widely used in the lightning protection of electronic equipment and systems in the fields of security, communications, transportation, petrochemicals, etc.
In electrical systems, there are usually four situations in which equipment is damaged by lightning.
(1) The equipment is directly damaged by lightning strikes.
(2) The strong lightning pulse generated by lightning intrudes into the equipment along the signal line, power line or other metal pipelines, and damages the equipment.
(3) During a lightning strike, the strong lightning current leaks into the ground through the down conductor and the access body, causing the grounding body of the equipment to generate an instantaneous high potential, forming a ground potential counterattack, and causing damage to the equipment.
(4) When lightning occurs, strong electric and magnetic fields will be formed around. During the equipment installation process, if the installation method is incorrect or the installation position is improper, it will be easily damaged due to the influence of electric and magnetic fields.
When multiple electrical systems coexist with buildings, the lightning channel of electrical and electronic equipment comes from four aspects: power supply system, antenna and feeder system, signal system, and grounding system. In the design of the intelligent surge protector, multi-level surge protectors should be installed in the above four aspects according to the actual situation.