Development of vacuum interrupter

The idea of using a vacuum medium to extinguish the arc was put forward at the end of the 19th century, and the earliest vacuum interrupter was produced in the 1920s. However, due to the limitations of vacuum technology, materials and other technical levels, it was not practical at that time. After the 1950s, with the development of new technologies, many difficulties in the manufacture of vacuum interrupters have been solved, and the vacuum switch has gradually reached a practical level. In the mid-1950s, the General Electric Company of the United States mass-produced vacuum circuit breakers with a rated breaking current of 12KA. Subsequently, in the late 1950s, due to the development of a vacuum interrupter with transverse magnetic field contacts, the rated breaking current was increased to the level of 3OKA. After the 1970s, Japan's Toshiba Electric Company successfully developed a vacuum interrupter with longitudinal magnetic field contacts The vacuum interrupter further increases the rated breaking current to more than 5OKA. At present, vacuum circuit breakers have been widely used in 1OKV and 35kV power distribution systems, and the rated breaking current can reach 5OKA-100KA. Some countries have also produced 72kV/84kV vacuum interrupters, but the number is not large.

In recent years, the production of vacuum circuit breakers in my country has also developed rapidly. At present, the technology of domestic vacuum interrupter is comparable to that of foreign products. There are vacuum interrupters using vertical and horizontal magnetic field technology and central ignition contact technology. Contacts made of Cu-Cr alloy materials have been successfully opened. The vacuum interrupter in China has reached a high level of breaking 5OKA and 63kAo, and the vacuum circuit breaker can completely choose the domestic vacuum interrupter.