CN202178539U - Dry type DC wall bushing - Google Patents

Abstract

The utility model relates to a dry-type DC wall bushing, which is characterized in that it includes a conductive rod, an insulating layer, an electrode layer, a silicon rubber hollow composite insulator and a fluid insulating glue; the outer layers of the conductive rod are alternately wrapped There are the insulating layer and the electrode layer, the outermost layer is the electrode layer; the conductive rod, the insulating layer and the electrode layer form a bushing core, and the bushing core is passed through the silicone rubber hollow composite insulator At the hollow position of the axis, the two ends of the conductive rod and the two ends of the silicone rubber hollow composite insulator are fixedly connected by bolts; between the sleeve cores, and between the sleeve cores and the silicone rubber The gaps between the hollow composite insulators are filled with the fluid insulating glue. The utility model has the characteristics of safe use, simple process and high yield, and is beneficial to the safe and stable operation of the direct current transmission system. The utility model can be widely used in direct current transmission systems.

Description

Dry type DC wall bushing

technical field

The utility model relates to a bushing, in particular to a dry-type DC wall-through bushing used in a DC power transmission system above 35kV.

Background technique

At present, there are two main design structures of wall-piercing bushings used in DC transmission systems: one is that electrical crepe paper is wound on the conductive rod to form a core, and then impregnated with insulating oil, and the outer insulation is undertaken by hollow porcelain insulators, referred to as oil-immersed. casing. The other is that electrical crepe paper is wound on a conductive rod to form a core, and then impregnated with epoxy resin and cured. The outer insulation is undertaken by hollow porcelain insulators or hollow composite insulators, referred to as pure dry bushings. However, the DC wall bushings of these two structures have the following shortcomings: 1. Due to the insulating oil inside the oil-immersed bushing, the valve hall of the DC converter station where the DC transmission system uses the wall bushing runs Bringing greater safety operating pressure, at present, the use of oil-immersed bushings is not recommended for the valve halls of newly-built DC converter stations. At the same time, the oil-immersed bushing can only use hollow porcelain insulators as the outer insulation. Therefore, the overall weight of the bushing is heavy and easily damaged, which brings great difficulties to transportation, installation and commissioning. 2. The pure dry bushing is impregnated and cured by epoxy resin. The impregnation and curing process is more complicated, and as the voltage level increases, the axial and radial length of the bushing increase, and the contradiction between impregnation and curing becomes more prominent. , It is very easy to cause partial discharge in the dry core due to poor process control, which eventually leads to a rapid decline in the yield of pure dry bushings, which makes the cost of the bushing very high. It can be seen from this that the wall bushings for DC systems with two structural forms in the prior art have disadvantages to varying degrees in terms of manufacture, technology and safe use.

Contents of the invention

In view of the above problems, the purpose of this utility model is to provide a dry-type DC wall bushing which is safe to use, has a high yield rate and low cost, and can ensure the safe and stable operation of the DC transmission system.

In order to achieve the above purpose, the utility model adopts the following technical solutions: a dry-type DC wall bushing, which is characterized in that it includes a conductive rod, an insulating layer, an electrode layer, a silicone rubber hollow composite insulator and a fluid insulating glue; The outer layer of the conductive rod is alternately wrapped with the insulating layer and the electrode layer, and the outermost layer is the electrode layer; the conductive rod, the insulating layer and the electrode layer form a sleeve core, and the sleeve core wears It is located at the hollow position of the shaft center of the silicone rubber hollow composite insulator, and the two ends of the conductive rod and the two ends of the silicone rubber hollow composite insulator are fixedly connected by bolts; between the sleeve cores, and the The gap between the bushing core and the silicone rubber hollow composite insulator is filled with the fluid insulating glue.

The conductive rod is made of aluminum alloy material with high conductivity.

The insulating layer is made of polytetrafluoroethylene tape.

The electrode layer is composed of more than one coaxial metal electrodes.

Because the utility model adopts the above technical scheme, it has the following advantages: 1. Since the utility model adopts the silicone rubber hollow composite insulator as the jacket, the weight of the dry-type DC wall bushing of the utility model can be effectively reduced, and the casing can be improved. Excellent anti-fouling flashover ability, and no explosion hazard, safe to use. 2. Since the utility model uses fluid insulating glue to fill between the bushing cores and the gap between the bushing core and the silicone rubber hollow composite insulator, the body insulating glue is not cured, the process is simple, and the filling is complete, so that The partial discharge index of the dry DC wall bushing of the utility model is greatly reduced and stabilized, thereby improving the yield of the dry DC wall bushing and effectively reducing production costs. 3. The utility model adopts the dry-type DC wall bushing which has oil-free characteristics, so it is beneficial to the safe and stable operation of the DC transmission system. The utility model can be widely used in direct current transmission systems.

Description of drawings

Fig. 1 is a schematic diagram of the overall structure of the utility model.

Detailed ways

Below in conjunction with accompanying drawing and embodiment the utility model is described in detail.

As shown in FIG. 1 , the utility model includes a conductive rod 1 , an insulating layer 2 , an electrode layer 3 , a silicone rubber hollow composite insulator 4 and a fluid insulating glue 5 . The outer layer of the conductive rod 1 is alternately wrapped with the insulating layer 2 and the electrode layer 3 until the outermost layer is the electrode layer 3. The conductive rod 1, the insulating layer 2 and the electrode layer 3 form a casing core. The bushing core is worn at the axial hollow position of the silicone rubber hollow composite insulator 4 as the jacket, and the two ends of the conductive rod 1 and the two ends of the silicone rubber hollow composite insulator 4 are fixedly connected by bolts. Wherein, the space between the bushing cores and between the bushing cores and the silicone rubber hollow composite insulator 4 is filled with uncured fluid insulating glue 5 .

In the above embodiments, the conductive rod 1 is made of aluminum alloy with high conductivity.

In the above embodiments, the insulating layer 2 is made of polytetrafluoroethylene tape, which has excellent insulating properties. The insulating layer 2 shortens axially layer by layer as the electrode layer 3 increases while being alternately wrapped with the electrode layer 3 .

In each of the above-mentioned embodiments, the electrode layer 3 is made up of n coaxial metal electrodes (n≥1), and the electrode layer 3 increases with the number of layers, the axial direction is shortened layer by layer, and the radial direction is increased layer by layer, which can make the utility model The axial and radial electric fields of the dry DC wall bushing are evenly distributed.

The above-mentioned embodiments are only used to illustrate the utility model, and the structure and connection mode of each component can be changed. The improvements and equivalent transformations should not be excluded from the protection scope of the present utility model.

Claims (5)

1. dry type direct current wall bushing, it is characterized in that: it comprises conducting rod, insulating barrier, electrode layer, silicon rubber hollow combined insulator and fluid insulation glue; The skin of said conducting rod alternating packets successively is tied with said insulating barrier and electrode layer, and outermost layer is said electrode layer; Said conducting rod, insulating barrier and electrode layer are formed the sleeve pipe core body; Said sleeve pipe core body is located in hollow position, said silicon rubber hollow combined insulator axle center, and the two ends of said conducting rod are connected through bolt with the two ends of said silicon rubber hollow combined insulator; Between the said sleeve pipe core body and the gap between said sleeve pipe core body and the said silicon rubber hollow combined insulator is filled with said fluid insulation glue.

2. dry type direct current wall bushing as claimed in claim 1 is characterized in that: said conducting rod adopts the aluminum alloy materials of high conductivity to process.

3. dry type direct current wall bushing as claimed in claim 1 is characterized in that: said insulating barrier adopts the polytetrafluoroethylene adhesive tape to process.

4. dry type direct current wall bushing as claimed in claim 2 is characterized in that: said insulating barrier adopts the polytetrafluoroethylene adhesive tape to process.

5. like claim 1 or 2 or 3 or 4 described dry type direct current wall bushings, it is characterized in that: said electrode layer is made up of more than one coaxial metal electrode.

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