How to Fill Sf6 Gas in Circuit Breaker?
What is Sf6 Circuit Breaker?
sf6 circuit breaker is a circuit breaker with SF6 gas as the insulating medium.
GIS consists of circuit breakers, isolating switches, grounding switches, transformers, arresters, busbars, connectors, and outlet terminals. These components are all enclosed in a metal grounded shell, and filled with a certain pressure of SF6 insulating gas, so it is also called SF6 fully enclosed combined electrical appliance.
Why Sf6 Gas is Used in Circuit Breaker/ What is the Function of Sf6 Circuit Breaker?
1. SF6 gas plays the role of insulation, arc extinguishing, and cooling in circuit breakers.
2. SF6 circuit breaker has a strong breaking capacity and allows more continuous breaking times, which is suitable for frequent operation. And the noise is low, there is no fire hazard, and the electromechanical wear is small.
3. The arc extinguishing ability of SF6 gas is stronger than that of ordinary air. The arc in SF6 is thinner and brighter than the arc in other media, indicating that the voltage is low, the arc extinguishing power is small, and the arc is easy to extinguish. The center is bright, indicating that the arc center temperature is high, the temperature difference with the surroundings is large, the natural convection ability is strong, and it is easy to dissipate heat and cool.
Because SF6 gas has a large negative charge, it can absorb a large number of free electrons, and the arc cannot be maintained once it loses free electrons. Therefore, the arc burning time in SF6 is shorter than that in oil and air, no carbon is produced at the contact point, and the arc extinguishing ability is reliable.
Where Sf6 Circuit Breaker is Used?
SF6 circuit breakers are used more and more in high-voltage circuits. However, due to its high price and high requirements for the application, management, and operation of SF6 gas, it is not widely used in medium voltage (35, 10kV), and is mainly used in voltage levels above 110kV.
How Does SF6 Circuit Breaker Work?
The working principle of the sf6 circuit breaker is to use sulfur hexafluoride as an inert gas, which has good insulation and arc extinguishing effect. A sulfur hexafluoride circuit breaker is an oil-free switchgear that uses SF6 gas as the insulating medium and arc extinguishing medium. Its insulation performance and arc extinguishing characteristics are much higher than those of oil circuit breakers. It is used to switch rated current, fault current or conversion line to realize protection, control, and operation of power transmission and transformation system.
How to Fill Sf6 Gas in Circuit Breaker?
The following introduces an SF6 circuit breaker gas filling kit produced by YUNENG. This SF6 circuit breaker gas filling kit can perform vacuuming and vacuum measurement on the device itself, SF6 switch, and GIS, and recycle SF6 gas in electrical equipment. Recovery processing includes purification and drying. Then SF6 gas is compressed and stored in the liquid state, and the electrical equipment is refilled with SF6 gas.
What is the SF6 Gas Refilling Process for Circuit Breakers?
SF6 gas refilling is a critical step in maintaining the proper operation of SF6 circuit breakers. It involves the removal of used SF6 gas, evacuation of the chamber, and refilling with fresh, purified gas. Here’s a detailed breakdown of the process:
1. SF6 Gas Recovery
- During SF6 gas refilling, the existing gas is first extracted from the circuit breaker’s gas chamber.
- The extracted gas automatically passes through a purification filter.
- The filtered gas is then compressed, cooled, and further purified by the SF6 compressor.
- This purified gas is stored in the SF6 storage tank in liquid form under high pressure.
2. Vacuuming the SF6 Switch
- A vacuum pump is used to remove air and moisture from the inside of the circuit breaker.
- This ensures that no contaminants are present in the chamber before refilling with fresh SF6 gas.
- The outlet of the vacuum pump is typically vented directly into the atmosphere, but proper environmental regulations and safety protocols must be followed.
3. SF6 Gas Refilling
- The purified and dried SF6 gas, stored in the dedicated tank, is then transferred back into the evacuated gas chamber.
- A pressure-reducing valve precisely controls the flow of gas, ensuring the chamber reaches the desired operating pressure.
Important Note:
SF6 gas is a potent greenhouse gas, and its release into the atmosphere should be strictly minimized.
Regulations and best practices for handling, recovering, and refilling SF6 gas should be strictly followed to minimize environmental impact and ensure safety.
This process highlights the importance of using specialized equipment and following proper procedures for SF6 gas refilling in circuit breakers. It’s crucial to prioritize safety, environmental responsibility, and adherence to relevant regulations while ensuring the proper operation of electrical equipment.
The SF6 gas recovery device produced by YUNENG can solve the problems of extraction, filtration, and filling of SF6 gas for you. You can tell us your questions or needs, and we will provide you with the best solution.
In addition to the SF6 gas recovery device, YUNENG can also provide you with various oil treatment equipment, including transformer oil, lubricating oil, hydraulic oil, turbine oil, and so on. Professional oil treatment equipment manufacturers are at your service.
