2022-09-07
2022-09-07
When the vacuum circuit breaker is in the closed position, its insulation to earth is undertaken by suitable insulators. Once a permanent ground fault occurs in the route connected to the vacuum circuit breaker, and the ground fault point is not cleared after the circuit breaker trips, the vacuum gap at the break of the circuit breaker should also be responsible for the ground insulation of the electrical bus. The vacuum insulation gap between the contacts should withstand various repair voltages without breakdown. Therefore, the insulation characteristics of the vacuum gap have become the current research content to improve the fracture voltage of the arc extinguishing chamber, and to make the single-break vacuum circuit breaker develop to a high voltage level. Vacuum circuit breakers are:
How vacuum circuit breakers work “Vacuum circuit breaker” is famous for its arc extinguishing medium and the insulating medium of the contact gap after arc extinguishing. It has the advantages of small size, light weight, light weight, etc. It is suitable for frequent operation. Therefore, it is widely used in distribution network. The working principle of vacuum circuit breakers is not complicated:
2. Anode-induced breakdown: The bombardment of the anode heats up a point due to the ion beam sent by the anode, producing melting and vapor, and a gap breakdown occurs. The conditions of anode breakdown are related to the electric field rise and fall index and the gap spacing. In addition, the circuit resistance of the vacuum circuit breaker is the main pyrogen that affects heating, and the circuit resistance of the arc extinguishing chamber usually accounts for more than 50% of the circuit resistance of the vacuum circuit breaker. The contact gap circuit resistance is the main component of the circuit resistance of the vacuum interrupter. Since the contact system is sealed in the vacuum interrupter, the heat generated can only be dissipated to the outside by the moving and static conducting rods. The breakdown principle of these vacuum gaps shows that the material of the vacuum stage and the surface of the stage are the key factors for the insulation of the vacuum gap.