"High-voltage vacuum circuit breaker" is named because its arc-extinguishing medium and the insulating medium in the contact gap after arc-extinguishing are both high vacuum; it is small in size, light in weight, and suitable for frequent operations and extinguishing. The arc has the advantage of not requiring maintenance and is widely used in distribution networks. Brief history of development: In 1893, Rittenhouse of the United States proposed a vacuum interrupter with a simple structure and obtained a design patent. In 1920, the Swedish Voga company made the first vacuum switch. Research results published in 1926 and others also showed the possibility of breaking current in vacuum. However, due to the small breaking capacity and limitations of the development level of vacuum technology and vacuum materials, it cannot yet be put into practical use. With the development of vacuum technology, it was only in the 1950s that the United States produced the first batch of vacuum switches suitable for cutting off capacitor banks and other special requirements. The breaking current was still at the level of 4,000 amps. Due to advances in vacuum material smelting technology and breakthroughs in vacuum switch contact structure research, in 1961, vacuum circuit breakers with a breaking current of 15 kV and a breaking current of 12.5 kA began to be produced. In 1966, vacuum circuit breakers of 15 kV, 26 kA and 31.5 kA were trial-produced, thus bringing vacuum circuit breakers into high-voltage and large-capacity power systems. In the mid-1980s, the breaking capacity of vacuum circuit breakers reached 100 kiloamps. China began to develop vacuum switches in 1958. In 1960, Xi'an Jiaotong University and Xi'an Switching Rectifier Factory jointly developed the first batch of 6.7 kV vacuum switches with a breaking capacity of 600 A; and later made 10 kV, breaking capacity Three-phase vacuum switch with a capacity of 1.5 kA. In 1969, Huaguang Electronic Tube Factory and Xi'an High Voltage Electrical Equipment Research Institute produced a 10 kV, 2 kA single-phase fast vacuum switch. After the 1970s, China has been able to independently develop and produce vacuum switches of various specifications.
Vacuum circuit breakers are usually divided into multiple voltage levels. Low-voltage types are generally used for explosion-proof electrical applications. Like coal mines and so on.