CN103151724B - A Gas Insulated Switchgear Based on In vivo Adsorption - Google Patents

Abstract

A gas insulated switchgear based on in vivo adsorption, the gas insulated switchgear is a sealed container (1) packed with insulating gas. The sealed container (1) is equipped with at least one pair of electrical contact electrodes, particle adsorption electrodes (8, 14), particle collection device (6) and adsorption device (15). The insulating gas is a mixture of fluorocarbon gas containing carbon and nitrogen or _CO2 or air; the particle adsorption electrodes (8, 14) are a pair of dust removal electrodes, respectively fixed on the inner wall of the sealed container (1) The two sides; the center line of the dust removal electrode and the center line of the electrical contact electrode are perpendicular to each other. The particle collecting device (6) is installed under the positive polarity electrode in the dust removal electrode, and collects the particles that the positive polarity electrode falls off. The gas insulation equipment is also equipped with an adsorption device; the adsorption device is installed on the top of the inner surface of the sealed container, and is used for adsorbing the low molecular weight gas produced by the decomposition of the mixed gas or the reaction in the sealed container.

Description

A Gas Insulated Switchgear Based on In vivo Adsorption

technical field

The invention relates to a switchgear using carbon-containing gas as an insulating medium, in particular to a switchgear using fluorocarbon gas as a medium.

Background technique

SF ₆ gas has good insulation ability, arc extinguishing ability, chemical stability and non-toxicity, so it is widely used in gas-insulated equipment, such as gas-insulated transformers, gas-insulated circuit breakers, gas-insulated transmission pipelines, etc. However, pure SF ₆ gas is very sensitive to the inhomogeneity of the electric field and requires high processing precision of equipment; and the discharge decomposition products of SF ₆ gas, such as SO ₂ F ₂ , SOF ₂ , SF ₄ , SF ₂ , H ₂ S, SOF Class ₄ , all are highly toxic substances, which pose a great threat to the health of personnel; in addition, the greenhouse effect of SF ₆ gas is very large, and its global warming potential (GWP) is about 23900 times that of CO ₂ gas, and in the atmosphere The lifespan is about 3200 years. Therefore, in the "Kyoto Protocol" signed by the parties to the United Nations Convention on Climate Change in 1997, SF ₆ gas was listed as one of the six restricted greenhouse gases. Therefore, researchers have conducted a lot of research, hoping to find a new medium that can replace SF ₆ gas for electrical equipment.

At present, it is very difficult to replace SF ₆ gas with a single gas. Therefore, people try to use mixed gas instead of pure SF ₆ gas. At present, there have been reports of using SF ₆ /N ₂ mixed gas or SF ₆ /CO ₂ mixed gas to replace pure SF ₆ gas. The use of mixed gas containing SF ₆ has the following advantages: lower sensitivity to electrode surface defects, lower gas liquefaction temperature , to reduce costs, so it has good application prospects, especially the SF ₆ /N ₂ mixed gas with SF ₆ content of 20% to 40%. However, the use of mixed gas containing SF ₆ cannot fundamentally solve the threat to the human body caused by the greenhouse effect of SF ₆ gas and the highly toxic substances contained in its decomposition products. Therefore, it is necessary to find a mixed gas that does not contain SF ₆ for high-voltage power equipment.

In the patent JP4119441B2, it is mentioned that N ₂ or O ₂ or dry air or CO ₂ are used as the main insulating gas components, and mixed with cC ₄ F ₈ (octafluorocyclobutane), CF ₃ SF ₅ , C ₃ F ₈ or CF ₃ OSF ₃ and other gases are used as the gas insulation medium of the gas insulation device;

Patents JP2004236459A, JP2006014411A, etc. also mention the use of mixed gases of cC ₄ F ₈ (octafluorocyclobutane), C ₃ F ₈ and N ₂ , CO ₂ etc. as electrical equipment insulation and arc extinguishing medium.

The above patents mentioned that the use of certain types of mixed gases mentioned above can greatly reduce the global warming coefficient of the insulating gas, and at the same time avoid the use of SF ₆ gas, and fundamentally solve the problem that the decomposition products of SF ₆ gas contain highly toxic Physical hazards from substances. However, there are also the following problems: since cC ₄ F ₈ (octafluorocyclobutane), C ₃ F ₈ , etc. in the above-mentioned gases contain carbon elements, the gas dissociates and recombines under the arc generated when the current is broken. , there is a problem of generating free carbon, and if the generated carbon is attached to the surface of a solid insulator such as an insulating spacer, the electrical insulation performance of this part may be significantly reduced.

At present, for conductive particles such as metal particles inside the equipment, there is a patent (Japanese Utility Model Publication No. 62-57511) that discloses a foreign matter capture device with a waveform on the bottom of the box. The conductive particles fall on the low electric field. To achieve harmless. Another patent (Japanese Utility Model Utility Publication No. 3-47323) discloses a method of increasing the curvature of the end of the pipe part to relieve the electric field to achieve enhanced insulation, because the end of the pipe part is where the electric field is easy to concentrate Therefore, the purpose of increasing the curvature of the end is to suppress the discharge from this part. However, this method only works on a small amount of conductive particles, and is not suitable for gas-insulated equipment that uses a carbon-containing mixed gas as an insulating and arc-extinguishing medium.

Contents of the invention

The object of the present invention is to overcome the above-mentioned shortcomings of the prior art, and provide a gas insulated switchgear. The present invention can reduce the global warming coefficient of the gas insulating medium used in electrical equipment, and the insulation performance will not be deteriorated due to the decomposition of the gas insulating medium. decline.

The gas insulated switchgear of the present invention is a sealed container filled with insulating gas. The airtight container is equipped with at least one pair of electrical contact electrodes, particle adsorption electrodes, particle collection device and adsorption device. The insulating gas is a mixed gas of fluorocarbon gas containing carbon element and nitrogen or CO ₂ or air. The electrical contact electrodes include static contacts and moving contacts; the particle adsorption electrodes are a pair of dust removal electrodes, which are respectively fixed on both sides of the inner wall of the sealed container. The center line of the dust removal electrode is perpendicular to the center line of the electrical contact electrode; the particle collection device is installed under the positive electrode in the dust removal electrode to collect particles falling off from the positive electrode; the gas insulated switchgear is also equipped with an adsorption device. The adsorption device is installed on the top of the inner surface of the sealed container, and is used for adsorbing the low molecular weight gas produced by the decomposition of the mixed gas or the reaction in the sealed container.

The gas insulated switchgear of the present invention conducts electricity by keeping the electrical contact electrodes in a contact state. When the current is disconnected, the electrodes are separated to generate an arc in the insulating gas, and the current is interrupted by extinguishing the arc. The insulating gas is a fluorocarbon gas containing carbon, such as a mixed gas of octafluorocyclobutane (cC ₄ F ₈ ), octafluoropropane (C ₃ F ₈ ) and nitrogen or CO ₂ or air.

The gas insulated switchgear is characterized in that a particle adsorption electrode and a particle collection device are installed.

The particle adsorption electrodes are a pair of dust removal electrodes, and the center lines of the dust removal electrodes and the center lines of the electrical contact electrodes are perpendicular to each other. The negative electrode in the pair of dust removal electrodes is a rod electrode, and the positive electrode is a semi-cylindrical electrode; the negative electrode is installed on one side of the inner wall of the sealed container, and the semi-cylindrical positive electrode is installed in the sealed container One side of the inner wall is controlled by an electromagnet installed between the positive electrode and the inner wall of the sealed container to generate vibration. A particle collection device is installed below the positive electrode, and the particles adsorbed on the positive electrode fall into the particle collection device after the dust removal electrode is powered off. At the same time, in order to ensure the collection of particles, when the electric contact electrode is disconnected, the movable contact moves to the positive side of the particle adsorption electrode, so that the arc is generated on the positive electrode side, ensuring that the particles can be adsorbed to the positive electrode; at the same time The outlet sleeve is installed on the other side where the arc is generated to prevent the generated carbon particles from falling on the surface of the outlet sleeve. In addition, an adsorption device is installed in the sealed container to absorb the low molecular weight gas produced by the decomposition of the above-mentioned mixed gas or the reaction in the sealed container. The adsorption device is composed of a placement box, a mesh bag and an adsorbent. The placement box is fixed on the top of the inner surface of the airtight container by means of screws or welding.

The particle collection device is designed as a particle trap structure. Once the particles enter, the particles will be inert due to the low local field strength of the particle trap. It can no longer compromise the insulation. In addition, the particle collection device is provided with a particle isolation plate, the particle isolation plate is a rectangular insulating plate, one side of the particle isolation plate is connected to the static contact support, and the other side of the particle isolation plate is connected to the inner partition of the sealed container , the role of the particle isolation plate is to prevent solid particles from being adsorbed on the surface of the lower outlet casing. The lower outlet sleeve is installed on the partition in the sealed container.

The gas insulated switchgear is also equipped with an adsorption device. The adsorption device is installed on the top of the inner surface of the sealed container, and is used for adsorbing the low molecular weight gas produced by the decomposition of the mixed gas or the reaction in the sealed container.

The invention is a gas insulated switchgear with low greenhouse effect insulating gas, which can prevent the deterioration of the gas insulation performance.

Description of drawings

Fig. 1 is a partial sectional view of a gas insulated switchgear according to an embodiment of the present invention;

Fig. 2 is a partial schematic diagram of a switchgear in an isolated and grounded state according to the present invention, Fig. 2a is a partial schematic diagram of a switchgear in an isolated state, and Fig. 2b is a partial schematic diagram of a switchgear in a grounded state;

Fig. 3 is the plan view of particle adsorption electrode used in the present invention;

Fig. 4 is a sectional view and a top view of the adsorption device used in the present invention, Fig. 4a is a sectional view, and Fig. 4b is a top view;

Fig. 5 is a top view of the mesh particle collection device used in the present invention.

detailed description

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

The gas insulated switchgear of the present invention is a sealed container filled with insulating gas. The airtight container is equipped with at least one pair of electric contact electrodes, particle adsorption electrodes, adsorption device and particle collection device.

Fig. 1 is a partial sectional view of a gas insulated switchgear according to an embodiment of the present invention. Figure 1 shows a load switch in the conduction state. A mixture of fluorocarbon gas containing carbon elements and nitrogen or _CO2 or air is packaged in the sealed container 1. There are upper outlet sleeve 2, lower outlet sleeve 3, moving contact seat 4, and grounding contact in the airtight container 1. 5. Moving contact 12, moving contact operating shaft 13, static contact and arc extinguishing grid 10, particle isolation plate 7, mesh particle collecting device 6, and adsorption device 15; in addition, it also includes a negative polarity electrode 14 And the particle adsorption electrode that positive polarity electrode 8 constitutes.

The negative electrode 14 in the particle adsorption electrode is a rod electrode, and the positive electrode 8 is a half cylindrical electrode; the negative electrode 14 is installed on one side of the inner wall of the sealed container 1, and the positive electrode is installed on On the other side of the sealed container 1, the positive electrode 8 is fixed on one side of the inner wall of the sealed container 1 by a fixed spring 11, and an electromagnet 9 is also installed between the positive electrode 8 and the sealed container 1, and the electromagnet 9 is located on the positive electrode. 8, when the electromagnet 9 is powered off, the operating rod of the electromagnet 9 is pushed against the positive electrode 8, and the fixed spring 11 is in a stretched state; when the electromagnet 9 is energized, the operating rod of the electromagnet 9 moves back, Under the tension of the fixed spring 11 , the positive electrode 8 retracts, that is, the positive electrode 8 can vibrate by energizing/de-energizing the electromagnet 9 and cooperating with the fixing spring 11 . When the switchgear of the present invention operates, the movable contact operating shaft 13 operates the movable contact 12 to rotate counterclockwise, and the arc extinguishing grid sheet extinguishes the arc. After the arc is extinguished, the external DC power supply supplies power to the particle adsorption electrodes 14 and 8, and the particles generated by the arc are adsorbed to the positive electrode 8 due to the effect of static electricity. After several times of disconnection and adsorption, power is supplied to the electromagnet 9 to cause the positive electrode 8 to vibrate, so that the solid particles adsorbed on the positive electrode 8 fall into the particle collection device 6 installed below the positive electrode 8 .

The lower outlet bushing 3 is installed on the other side of the running direction of the moving contact 12; the particle isolation plate 7 is installed between the static contact support 17 and the partition 16 of the sealed container 1, and its function is to avoid the adsorption of solid particles On the surface of the lower outlet casing 3. The adsorption device 15 adsorbs the low-molecular-weight gas generated by the decomposition of the above-mentioned mixed gas or the reaction in the sealed container. The upper outlet sleeve 2 is located on the upper surface of the airtight container 1 , and the lower outlet sleeve 3 is located on the partition 16 inside the airtight container 1 . The upper and lower outlet bushings are used for insulating the electrified body from the sealed container 1 and connecting conductors inside and outside the sealed container 1 .

Fig. 2 is a partial schematic diagram of the switchgear in the isolation and grounding state of the present invention, Fig. 2a is a schematic diagram of the switchgear in the isolation state, and Fig. 2b is a schematic diagram of the switchgear in the grounding state; An arc is generated between 10 and the moving contact 12; when the switch is turned off, the moving contact 12 moves to the upper right.

Fig. 3 is a top view of the particle adsorption electrode. As shown in Figure 3, the negative polarity electrode 14 is a rod-shaped electrode, which can produce higher field strength at a lower voltage, and the positive polarity electrode 8 is a semi-cylindrical electrode, which can adsorb solid particles. In order to ensure that the electrodes are uniform, the semicircular The shape of both ends of the barrel electrode is a rounded surface 18 .

Fig. 4 is a sectional view of the adsorption device. As shown in FIG. 4 , the adsorption device 15 is composed of a storage box 151 , a mesh bag 153 and an adsorbent 152 . The placement box 151 is fixed on the top of the inner surface of the airtight container 1 by means of screws or welding; the adsorbent 152 is packed into the mesh bag 153 . The material of the adsorbent 152 can be activated alumina, molecular sieve, silica gel, etc.; The placement box 151 is a porous box made of thin iron sheet or steel plate.

Fig. 5 is a top view of the particle collection device. As shown in Figure 5, the particle collection device 6 is a thin steel plate with a particle trap 61, which is fixed on the partition 16 of the airtight container 1; the left half particle trap of the particle collection device 6 is smaller, and the particle trap depth of the right half and wider. After the solid particles fall into the particle trap 61, due to the decrease of the local field strength in the trap, the solid particles trapped in it are not easy to move again. At the same time, the surface of the particle trap 61 is also coated with a viscous substance, so that the solid position is stuck and cannot move. and the role of fixed particles.

Claims (4)

1. based on the gas-insulated switchgear adsorbed in body, it is characterized in that: described gas-insulated switchgear is the airtight container (1) of an inclosure insulating gas; Described airtight container (1), built with at least one pair of electrical contact electrode, is also equipped with particulate adsorption electrode (8,14), particulate collection device (6) and adsorbent equipment (15); Described electrical contact electrode comprises fixed contact and moving contact; Described insulating gas is fluorocarbon gas containing carbon and nitrogen or CO ₂or the mist of air; Described particulate adsorption electrode (8,14) is a pair electrodes for removing dust, is separately fixed at the both sides of airtight container (1) inwall; Center line and the electrical contact center lines of electrodes of electrodes for removing dust are orthogonal; Particulate collection device (6) is arranged on the below of the straight polarity electrode in electrodes for removing dust, collects the particulate that straight polarity electrode comes off; Described gas-insulated switchgear is also provided with adsorbent equipment; Adsorbent equipment is arranged on the top of airtight container inner surface, for adsorbing the low-molecular-weight gas produced due to reaction in the decomposition of described fluorine carbon mist or airtight container;

Described particulate collection device (6) is fixed on dividing plate (16); Particulate collection device (6) is one block of sheet metal with particulate trap (61); The left half of particulate trap of particulate collection device (6) is less, the particulate trap depth of right one side of something and width larger; Described particulate trap (61) surface scribbles stickum;

In described airtight container (1), particulate division board (7) is housed, particulate division board (7) is arranged between the dividing plate (16) of fixed contact bearing (17) and airtight container (1), prevent solia particle to be adsorbed on the surface of lower outlet casing tube (3), described fixed contact bearing (17) is for installing the fixed contact of electrical contact electrode.

2. gas-insulated switchgear according to claim 1, is characterized in that: in described particulate adsorption electrode, and negative-pole electrode (14) is bar electrode, and straight polarity electrode (8) is semi-circular cylindrical electrode; Described negative-pole electrode is arranged on the side of airtight container inwall, the straight polarity electrode of described semi-circular cylindrical is arranged on the opposite side of airtight container (1) inwall, produces vibration by the magnet control be arranged between described straight polarity electrode and airtight container inwall; Described particulate adsorption electrode is powered by external direct current power supply.

3. gas-insulated switchgear according to claim 2, it is characterized in that: described straight polarity electrode (8) is fixed on airtight container (1) by fixing spring (11), electromagnet (9) is also housed between straight polarity electrode (8) and airtight container (1), and electromagnet (9) is positioned at the center of straight polarity electrode (8); During electromagnet (9) power-off, the actuating strut of electromagnet (9) withstands on straight polarity electrode (8), and fixing spring (11) is in extended state; During electromagnet (9) energising, the actuating strut action retraction of electromagnet (9), by the stretching action of fixing spring (11), straight polarity electrode (8) bounces back.

4. gas-insulated switchgear according to claim 1, is characterized in that: described adsorbent equipment (15) is by holder (151), and mesh bag (153) and adsorbent (152) are formed; Holder (151) is fixed on the top of airtight container (1) inner surface; Adsorbent (152) loads in mesh bag (153); Mesh bag (153) puts into holder (151); Holder (151) is the porous box be made up of sheet iron or steel plate.