40.5kV 72.5kV 145kV 170kV 245kV Dead tank Vacuum Circuit-Breaker

1. Their core difference is arc-extinguishing media: Vacuum breakers use high vacuum (10⁻⁴~10⁻⁶Pa) for insulation and arc extinction; SF₆ breakers rely on SF₆ gas, which adsorbs electrons well to quench arcs.
2. In voltage adaptation: Vacuum breakers fit medium-low voltages (10kV, 35kV; some up to 110kV), rarely 220kV+. SF₆ breakers suit high-ultra high voltages (110kV~1000kV), mainstream for ultra-high voltage grids.
3. For performance: Vacuum breakers extinguish arcs fast (<10ms), have 63kA~125kA breaking capacity, suit frequent use (e.g., power distribution) with long life (>10,000 cycles). SF₆ breakers excel in stable large/inductive current breaking but work less frequently, needing insulation recovery time post-extinction.
4. Compared to SF6 gas circuit breakers, vacuum circuit breakers can achieve zero greenhouse gas emissions and are more environmentally friendly because the arc extinguishing device does not contain any gas

Integral Tank Structure：

• Integral Tank Structure: The breaker's arc quenching chamber, insulating medium, and related components are sealed within a metal tank filled with an insulating gas (such as sulfur hexafluoride) or insulating oil. This forms a relatively independent and sealed space, effectively preventing external environmental factors from affecting the internal components. This design enhances the insulation performance and reliability of the equipment, making it suitable for various harsh outdoor environments.

Arc Quenching Chamber Layout：

• Arc Quenching Chamber Layout: The arc quenching chamber is typically installed inside the tank. Its structure is designed to be compact, enabling efficient arc quenching within a limited space. Depending on different arc quenching principles and technologies, the specific construction of the arc quenching chamber may vary, but generally includes key components such as contacts, nozzles, and insulating materials. These components work together to ensure that the arc is quickly and effectively extinguished when the breaker interrupts the current.

Operating Mechanism：

• Operating Mechanism: Common operating mechanisms include spring-operated mechanisms and hydraulic-operated mechanisms.

• Spring-Operated Mechanism: This type of mechanism is simple in structure, highly reliable, and easy to maintain. It drives the opening and closing operations of the breaker through the energy storage and release of springs.

• Hydraulic-Operated Mechanism: This mechanism offers advantages such as high output power and smooth operation, making it suitable for high-voltage and high-current class breakers.

1. Environmentally friendly gas mixed insulation technology
CO ₂ and perfluoroketone/nitrile mixture gases: such as CO ₂/C ₅ - PFK (perfluoroketone) or CO ₂/C ₄ - PFN (perfluoronitrile) mixture gases. These mixed gases combine the arc extinguishing ability of CO ₂ and the high dielectric strength of perfluorinated ketones/nitriles, making them a substitute for SF ₆ in high-voltage applications. For example, CO ₂/C ₄ - PFN mixed gas has been commercially applied in high-voltage circuit breakers, with insulation and breaking performance close to SF ₆, and significantly reduced global warming potential (GWP).
Air and perfluoroketone mixed gas: In medium pressure applications, the mixture of air and C ₅ - PFK can be used as an insulation medium. By optimizing the mixing ratio and pressure, insulation performance comparable to SF ₆ can be achieved while reducing environmental impact.
2. Vacuum circuit breaker technology
Vacuum arc extinguishing chamber: Utilizing the high insulation strength and fast arc extinguishing ability in a vacuum environment, it replaces the arc extinguishing function of SF ₆. Vacuum circuit breakers are widely used in the medium and low voltage fields, especially in scenarios with high environmental requirements. Its advantages are no greenhouse gas emissions and excellent arc extinguishing performance, but it needs to solve problems such as vacuum sealing and contact materials.
Combination of vacuum circuit breaker and gas insulation: In some medium voltage switchgear, vacuum circuit breakers are used as breaking elements, combined with dry air or nitrogen as insulation media, to form environmentally friendly gas insulated switchgear (GIS) that balances insulation and arc extinguishing performance.