CN106158181A - Metal oxide arrester - Google Patents

Abstract

The invention discloses a metal oxide lightning arrester, which comprises a hollow insulating cylinder, an upper metal sealing plate at the upper end of the hollow insulating cylinder, a lower metal sealing plate at the lower end of the hollow insulating cylinder, a conductive column axially arranged in the hollow insulating cylinder, and a covering On the umbrella group on the outer surface of the hollow insulating cylinder, there is a gap between the hollow insulating cylinder and the conductive column in the radial direction, the upper end of the conductive column is in contact with the upper metal sealing plate, and the lower end of the conductive column is in contact with the lower metal sealing plate, The conductive column is formed by alternately stacking zinc oxide resistor sheets and metal conductors. The invention provides a metal oxide arrester with high heat dissipation performance, which solves the defects that the metal oxide arrester with the existing structure is prone to thermal collapse and thermal explosion.

Description

metal oxide arrester

technical field

The invention relates to a metal oxide lightning arrester, which belongs to the technical field of electric equipment.

Background technique

Surge arresters are protective devices used to protect the insulation performance of electrical equipment in power systems from lightning overvoltage damage, or to avoid internal overvoltage damage caused by equipment operation. It is an important protection link related to the safe and stable operation of power systems. With the increase of the voltage level, the system overvoltage problem becomes increasingly prominent, and it is particularly important to improve the operation performance of the arrester.

The structure of the metal oxide arrester in the prior art is that a plurality of non-linear resistance sheets mainly composed of zinc oxide are stacked together in an insulating container provided with upper and lower electrodes. It has a very high resistance when the voltage is normal, so it is in an insulating state. When an overvoltage occurs in the system, the impact current enters the ground through the resistor, and the voltage drop (residual voltage) of the resistor itself is maintained at Within a certain range, the overvoltage amplitude on the equipment connected in parallel with the arrester is limited and the equipment is protected. However, in addition to the long-term power frequency voltage, the metal oxide arrester with this structure also intermittently withstands transient overvoltages such as power frequency overvoltage, lightning overvoltage, and operating overvoltage, which can easily lead to an increase in the temperature of the internal zinc oxide resistor. High, and the heat cannot be effectively dissipated. When the temperature exceeds a certain limit value for a long time, it will cause thermal damage (thermal collapse) of the arrester. In addition, in the thunderstorm season, when the arrester is struck by violent lightning, a large lightning shock current flows through the resistor sheet, causing it to absorb a large amount of impact energy. Because the energy cannot be effectively transmitted and released quickly, the gas pressure and temperature inside the arrester increase sharply. , often lead to explosion accidents, seriously affecting the safe and stable operation of the power system.

Contents of the invention

The object of the present invention is to provide a metal oxide arrester, aiming at the defect that the metal oxide arrester of the existing structure is prone to thermal collapse and thermal explosion, and provides a metal oxide arrester with high heat dissipation performance.

The purpose of the present invention is achieved through the following technical solutions:

A metal oxide lightning arrester, comprising a hollow insulating cylinder 2, an upper metal sealing plate 3 at the upper end of the hollow insulating cylinder 2, a lower metal sealing plate 4 at the lower end of the hollow insulating cylinder 2, and a conductive column 5 axially arranged in the hollow insulating cylinder 2 1. The umbrella group 6 coated on the outer surface of the hollow insulating cylinder 2, there is a gap 7 in the radial direction between the hollow insulating cylinder 2 and the conductive column 5, the upper end of the conductive column 5 is in contact with the upper metal sealing plate 3, and the conductive column 5 is in contact with the upper metal sealing plate 3. The lower end of the column 5 is in contact with the lower metal sealing plate 4 , and the conductive column 5 is formed by alternately stacking zinc oxide resistance sheets 8 and metal conductors 9 .

The object of the present invention can also be further realized by the following technical measures:

In the aforementioned metal oxide arrester, the metal conductor 9 is in the shape of an "I".

In the aforementioned metal oxide arrester, the metal conductor 9 is made of aluminum or copper.

In the aforementioned metal oxide arrester, the gap 7 is filled with a fluid insulating material 10, and the fluid insulating material 10 is insulating gas or insulating liquid.

In the aforementioned metal oxide arrester, the material of the hollow insulating cylinder 2 is epoxy resin, and the matrix of the epoxy resin is evenly distributed with heat-conducting particles.

In the aforementioned metal oxide arrester, the umbrella group 6 is made of silicone rubber, and the matrix of the silicone rubber is evenly distributed with heat-conducting particles.

In the aforementioned metal oxide arrester, the metal conductor 9 is provided with through holes 11 in the radial direction.

In the aforementioned metal oxide arrester, the metal conductor 9 has a radial through-hole 11 in the middle of the "I"-shaped structure.

The aforementioned metal oxide arrester, wherein the thermally conductive particles are a combination or one of aluminum oxide, silicon oxide, zinc oxide, aluminum nitride, boron nitride, silicon carbide, and graphite.

Compared with prior art, the beneficial effect of the present invention is:

1. Using metal conductors, using the excellent thermal conductivity of metal materials such as copper or aluminum, speeds up heat transfer, and avoids thermal collapse or thermal explosion caused by heat concentration when the zinc oxide resistance sheet is subjected to overvoltage and high lightning strike current , At the same time, the "I"-shaped structure of the metal conductor is conducive to increasing the contact area with the surrounding medium and reducing the volume and weight.

2. Using insulating gas or insulating liquid as the filling medium, the fluidity of the fluid can be used to accelerate heat conduction and diffusion.

3. The use of thermally conductive particles in the material of the insulating tube and the umbrella group can increase the thermal conductivity of the material, improve the heat exchange capacity between the arrester and the external environment, and improve the overall heat dissipation effect.

4. The through-hole structure on the "I"-shaped metal conductor can increase the flow path of the fluid and improve the heat dissipation effect.

Description of drawings

Fig. 1 is the structural representation of metal oxide arrester of the present invention;

Fig. 2 is a schematic diagram of a through-hole structure for an "I"-shaped metal conductor.

detailed description

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

As shown in FIG. 1 , it is a schematic structural diagram of a metal oxide arrester 1 provided by a preferred embodiment of the present invention. The metal oxide arrester 1 includes a hollow insulating cylinder 2, an upper metal sealing plate 3 at the upper end of the hollow insulating cylinder 2, a lower metal sealing plate 4 at the lower end of the hollow insulating cylinder 2, a conductive column 5 axially arranged in the center of the hollow insulating cylinder 2, The umbrella group 6 covering the outside of the hollow insulating cylinder 2. There is a gap 7 in the radial direction between the hollow insulating cylinder 2 and the conductive column 5. The conductive column 5 is formed by alternately stacking zinc oxide resistance sheets 8 and "I"-shaped metal conductors 9. The upper end of the conductive column 5 is connected to the upper metal sealing plate 3 contact, the lower end of the conductive column 5 is in contact with the lower metal sealing plate 4 .

The material of the "I"-shaped metal conductor 9 can be any one of aluminum or copper, and its excellent thermal conductivity can accelerate heat conduction.

The gap 7 can be further filled with a fluid insulating material 10 . The fluid insulating material 10 may be any of an insulating gas or an insulating liquid. The insulating gas mentioned above can be dry air, nitrogen, or sulfur hexafluoride. The above insulating liquid may be aromatic synthetic oil, silicone oil, ester oil, or ether and sulfone synthetic oil. While ensuring the electrical insulation performance of the gap 7, the above-mentioned materials can accelerate heat conduction and diffusion by utilizing the fluidity of the fluid.

The hollow insulating cylinder 2 is a cylindrical glass fiber reinforced epoxy resin tube with a hollow structure wound and formed. In this embodiment, thermal conductive particles are evenly distributed in the epoxy resin as the base material. The above-mentioned thermally conductive particles may be a combination of aluminum oxide, silicon oxide, zinc oxide, aluminum nitride, boron nitride, silicon carbide, graphite or one of them. While ensuring the electrical insulation performance of the hollow insulating cylinder 2, its thermal conductivity is improved.

The umbrella group 6 is covered on the outside of the hollow insulating cylinder 2 by vulcanization (curing) of silicone rubber. The aforementioned silicone rubber may be high temperature vulcanized silicone rubber, room temperature vulcanized silicone rubber, or liquid silicone rubber. In this embodiment, heat-conducting particles are evenly distributed in the silicone rubber as the matrix material. The above-mentioned thermally conductive particles may be one or a combination of aluminum oxide, silicon oxide, zinc oxide, aluminum nitride, boron nitride, silicon carbide, and graphite. While ensuring the electrical insulation performance of the umbrella group 6, its thermal conductivity is improved.

As shown in FIG. 2 , further opening a through hole 11 on the axis of the "I"-shaped metal conductor 9 can increase the flow path of the fluid insulating material 10 and further improve the heat dissipation effect.

In addition to the above-mentioned embodiments, the present invention can also have other implementations, and all technical solutions formed by equivalent replacement or transformation fall within the scope of protection required by the present invention.

Claims (10)

1. a metal oxide arrester, including hollow insulating cylinder, the upper metal shrouding of hollow insulating cylinder upper end, hollow insulation The cylinder lower metal shrouding of lower end, the conductive pole being axially disposed within hollow insulating cylinder, it is coated on the umbrella of hollow insulating cylinder outer surface Group, there is gap in described hollow insulating cylinder and conductive pole, the upper end of described conductive pole contacts with upper metal shrouding, institute diametrically The lower end stating conductive pole contacts with lower metal shrouding, it is characterised in that described conductive pole is by zinc oxide resistance sheet and metallic conductor It is alternately superimposed on forming.

2. metal oxide arrester as claimed in claim 1, it is characterised in that described metallic conductor is I-shaped knot Structure.

3. metal oxide arrester as claimed in claim 1, it is characterised in that the material of described metallic conductor be aluminum or Copper.

4. metal oxide arrester as claimed in claim 1, it is characterised in that be filled with fluid insulation material in described gap Material, described fluid insulating material is insulating properties gas or insulating liquid.

5. metal oxide arrester as claimed in claim 1, it is characterised in that the material of described hollow insulating cylinder is epoxy Resin, the matrix of described epoxy resin is evenly distributed with conductive particles.

6. metal oxide arrester as claimed in claim 1, it is characterised in that the material of described cluster parachute is silicone rubber, institute The matrix stating silicone rubber is evenly distributed with conductive particles.

7. metal oxide arrester as claimed in claim 1, it is characterised in that described metallic conductor be radially provided with logical Hole.

8. metal oxide arrester as claimed in claim 2, it is characterised in that described metallic conductor is in I-shaped structure Middle part offer radial direction through hole.

9. metal oxide arrester as claimed in claim 5, it is characterised in that described conductive particles is aluminium oxide, oxidation Silicon, zinc oxide, aluminium nitride, boron nitride, carborundum, the combination of graphite or one of which.

10. metal oxide arrester as claimed in claim 6, it is characterised in that described conductive particles is aluminium oxide, oxidation Silicon, zinc oxide, aluminium nitride, boron nitride, carborundum, the combination of graphite or one of which.