Closed switching device, and arc extinguish chamber and tank of closed switching device

Abstract

The invention discloses a closed switching device, and an arc extinguishing chamber and a tank of the closed switching device. A fixed insulating sleeve in the arc extinguishing chamber can be plugged into a tank body from a feed opening and is positioned through fitting of the outer wall of the fixed insulating sleeve and the inner wall of the tank body, so that the fixed insulating sleeve is provided between an exhaust portion of a blow-out side and the inner wall of the tank body, and the inner wall of the fixed insulating sleeve is a baffling face, used for blocking insulating gas ejected from the blow-out side so that the ejected insulating gas is baffled. When the closed switching device is in use, the insulating gas ejected from a spout of a moving contact end extinguishes high tension arc in a section and is then ejected out of the moving contact end and / or a fixed contact end; meanwhile, the insulating gas is high in both flowing speed and temperature and carries metal dust and ionization breakdown product, high-temperature high-speed mixed gas collides the baffling face of the fixed insulating sleeve, and the mixed gas ejected from the blow-out side is prevented from causing impact erosion to the inner wall of the tank body accordingly.

Description

technical field [0001] The invention relates to a closed switchgear, an arc extinguishing chamber and a tank body thereof. Background technique [0002] At present, the commonly used insulation methods in switchgear are divided into gas insulation and fixed insulation. The method of gas insulation is to fill sulfur hexafluoride gas, nitrogen, etc. Vinyl fluoride, electric ceramic materials, glass fiber cloth, resin materials, etc., and the gas insulation method is generally used in the ground insulation of metal-enclosed switchgear, and its advantage is that the form of the gas is not fixed, especially the switch that uses gas blowing to extinguish the arc. Equipment, gas insulation is to play the role of arc extinguishing. However, no matter whether sulfur hexafluoride gas or nitrogen is used for gas insulation, its insulation strength is lower than that of fixed insulation materials in fixed insulation, and the insulation performance of insulating gas will be affected by ...

AI Technical Summary

Problems solved by technology

However, because the high-temperature arc between the dynamic and static connection ends will heat the insulating gas, the pressure of the insulating gas will increase and the insulation capacity will decrease. However, the dynamic connection end of the arc extinguishing chamber uses mechanical means to create a pressure difference or uses the pressure difference of the arc extinguishing chamber itself The arc is extinguished, and the high-temperature insulating gas is blown to the static terminal of the arc extinguishing chamber for cooling. Therefore, during the cooling process of the high-temperature insulating gas, the gas will ablate the components of the static terminal of the arc extinguishing chamber to A certain amount of metal dust and ionized decomposition products are produced in the airflow channel of the electric terminal. This part of the dust and decomposition products and the insulating gas that has not been completely cooled will be directly sprayed from the air outlet side of the static terminal to the inner wall of the tank. , the dust and decomposition products mixed in the insulating gas will burn and erode the tank wall of the tank body, resulting in uneven inner wall surface of the tank body, which will cause breakdown or discharge of the arc extinguishing chamber to the ground, so the gas-insulated metal-enclosed switch The equipment usually needs to reduce the temperature of the insulating gas by extending the airflow channel at the static end of the arc extinguishing chamber

[0004] However, if the air flow channel is to be extended in a limited space, baffles can only be added to the cooling channel in the static terminal of the arc extinguishing chamber, but the effect of the baffles is also limited. When the gas-insulated metal-enclosed switchgear When the inner diameter of the tank shrinks to a certain extent, the insulation to the ground will become very sensitive. As long as there is a slight decrease in the insulation performance, it will cause discharge or breakdown to the ground. Performance will have little impact

[0005] With the progress of society and the increase of population density, the requirements of modern society for the utilization of space are also increasing, so that the market demand for the reduction of the size of metal-enclosed switchgear is getting higher and higher, such as the requirements of power grid bidding Among them, the width of 252kV three-phase split-phase metal-enclosed switchgear has been reduced from the original 2300mm to 1500mm, such as a circuit breaker with sulfur hexafluoride gas as the insulating medium. The tank diameter has been reduced to a limit. If the tank diameter is further reduced, the only way to increase the pressure of the insulating gas in the tank is, but this method not only wastes gas, but also has an impact on the safety of metal-enclosed switchgear. After all, increasing the design pressure, Not only does it add to the cost of materials, but it also requires a higher level of professional qualification

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