Analysis on the technological innovation and market development needs of solid-sealed poles
The phase column insulation of the vacuum circuit breaker has been layered with air insulation, composite insulation, and sealed insulation. This has formed the third generation of vacuum circuit breakers in terms of insulation. In the first generation of air insulation, the live parts are completely exposed to the air. Its insulation level changes with the humidity, dust in the air, and bumps during transportation, and is easily affected by foreign objects such as small animals. In the first generation of composite insulation, the vacuum arc is protected in an epoxy resin sleeve. However, this sleeve does not completely wrap the high-voltage live parts, and the inside will still be affected by dust, moisture, insects, etc. The third generation of insulation is Embedded Pole. It uses the APG process to use epoxy resin to seal the vacuum arc chamber and the upper and lower outlet terminals, making the vacuum arc chamber, upper and lower outlets, and connectors an integral part of the vacuum circuit breaker. In this way, not only the size of the vacuum interrupter is reduced, but also the problem of the live part being unaffected by the external environment (environment, humidity, altitude, etc.) is completely solved, and the weather resistance is improved. At this time, the epoxy resin not only serves as the main insulation of the primary part, but also its mechanical support. Its electric field distribution and stress distribution are better than those of various shapes of insulating partition structures.