JPH10134659A - Oil-filled electric equipment containing adsorbent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide oil-filled electric equipment containing an adsorbent, in which a periodic oil cleaning work can be obviated and an insulating property of insulating oil cannot be deteriorated even if water intrudes into the oil during a long-term use. SOLUTION: In oil-filled electric equipment, an adsorbent 9 housed inside a container 10 is disposed on an oil passage communicating an expansion chamber 7 or a conservator with the main body of the equipment, thereby causing an oil flow due to volume expansion/contraction of insulating oil to pass through the adsorbent 9. Consequently, it is possible to effectively remove water included in the insulating oil. A valve for bypassing may be disposed on the oil passage, to replace the adsorbent 9 during operation of the equipment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil-filled electric device containing an adsorbent used in the technical field of power transmission and distribution.

[0002]

2. Description of the Related Art Oil-filled electrical devices such as oil-filled bushings, oil-filled transformers, oil-filled reactors, and oil-filled CTs have insulating materials such as insulating oil, insulating paper, press boards, and synthetic resins. I have. The insulating properties of all of these insulators are significantly reduced due to the incorporation of moisture. In addition, if the operation is continued for a long time in a state in which water is mixed, there is a concern that the strength of insulating paper or the like may be reduced due to hydrolysis by water and heat, and the insulating properties may be reduced.

In order to prevent such a problem, electric equipment manufacturers have conventionally made extensive use of a hermetically sealed structure by welding to ensure thorough sealing. However, there are some places where welding cannot be adopted due to maintenance or the material of the mounting parts, so that gaskets having gas permeability, jackets made of organic materials, rubber bags, and the like have to be used. As a result, it has not been possible to completely prevent these oil-filled electrical devices from invading moisture due to long-term use and deteriorating the insulation properties.

In gas-insulated equipment, this problem is solved by using an adsorbent. Since water molecules can move almost freely in the insulating gas, it is possible to adsorb water molecules regardless of where the adsorbent is placed in the enclosed space in the gas insulation equipment, and the adsorbent works effectively. . In contrast, in oil-filled electrical equipment, water molecules dissolve in insulating oil, preventing free movement. as a result,
Moisture absorption is performed only on the insulating oil at the periphery of the adsorbent, and the adsorbent cannot be effectively acted on unlike gas-insulated equipment.

[0005] Therefore, in the oil-filled electric equipment, the moisture control by the adsorbent is not sufficient, and it is essential to perform an oil purification operation in which the insulating oil is extracted to the outside by a pump at regular intervals and heated and dehydrated. An adsorbent is also used as one of the oil purification methods. However, it is necessary to extract the insulating oil to the outside by a pump and pass it through the adsorbent layer.
For this reason, it is necessary to stop the oil-filled electrical equipment at regular intervals, and also to prevent the moisture in the insulating oil from gradually increasing from the start of use to immediately before the oil purification work, thereby preventing the insulation characteristics from gradually decreasing. I couldn't.

[0006]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems, does not require periodic oil purification work, and maintains the insulating properties of insulating oil even if moisture has entered during years of use. The present invention has been made to provide an oil-filled electric device containing an adsorbent, which does not lower the oil content.

[0007]

An oil-filled electric device containing an adsorbent according to the present invention, which has been made to solve the above-mentioned problems, has an adsorbent in an oil passage communicating between an expansion chamber or a conservator and the main body of the device. Are arranged so that the flow of oil due to the volume expansion and contraction of the insulating oil is performed through the adsorbent. Inside the oil-filled electrical equipment, there is a flow of oil due to volume expansion and contraction caused by the temperature difference between day and night and the difference in the amount of electric power, and the flow of oil passes through the adsorbent so that the adsorption of moisture is always Done. Therefore,
In the oil-filled electrical device of the present invention, the water that has entered the insulating oil is easily removed, and the insulating properties of the insulating oil do not deteriorate even if the periodic oil purification operation is not performed.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below. 1 and 2 are views showing a first embodiment in which the present invention is applied to an oil-filled bushing. In FIG.
1 is an air-side insulator, 2 is an oil-side insulator, 3 is a mounting flange metal fitting located at the center of the insulator, 4 is a center conductor, and 5 is an oil-impregnated paper core on the outer periphery of the center conductor 4. An insulating oil 6 is filled in the inside of the insulator tube which is the device main body. Reference numeral 7 denotes an expansion chamber in the head. A tension is applied to the center conductor 4 by a center clamp spring 8 provided in the expansion chamber, and the air-side insulator 1, the oil-side insulator 2, the mounting flange 3, etc. It has a center clamp structure to make close contact.

The expansion chamber 7 is a chamber into which the insulating oil 6 flows when the insulating oil 6 inside the apparatus main body (insulator tube) expands in volume due to heat generation of the center conductor 4 or the like. As shown in FIG. 5, an adsorbent 9 is disposed in an oil passage communicating between the expansion chamber 7 and the device main body. The adsorbent 9 is for adsorbing water in the insulating oil 6 to prevent the insulating properties of the insulating oil from being deteriorated.
Solid catalysts with high hydrophilicity such as alumina and clay are used, but synthetic zeolites are most effective.

The adsorbent 9 is preferably a granular material stored in a container 10 through which the insulating oil 6 can flow. In this embodiment, the adsorbent 9 is stored in a wire mesh container 10 manufactured by punching or etching. I have. Container 10 has top surface 11 and bottom surface
12 is a metal plate, and the exit and entrance are wire mesh. Then, as shown in FIG. 2, the upper surface 11 of the container 10 and the spring seat
The space between the bottom 13 of the container 10 and the bottom of the expansion chamber 7 is also sealed by the gasket 15. For this reason, the flow of oil due to volume expansion / contraction always passes through the adsorbent 9 in the container 10.

It is preferable to form a fibrous coating on the inner surface of the wire netting container 10 to prevent the fine powder, which may be generated due to damage of the adsorbent 9, from flowing into the insulating oil 6. As the fibrous coating, a nonwoven fabric, cloth, paper, or the like made of a fiber having good oil resistance such as glass fiber can be used.

In the oil-filled bushing constructed as described above, the volume expansion and contraction of the insulating oil 6 caused by the temperature difference between day and night and the difference in the amount of electric power causes the expansion chamber 7 and the main body of the device to be separated. A forced flow of insulating oil 6 occurs between the two, but this oil flow always occurs through adsorbent 9 in vessel 10. This flow allows the insulating oil 6 to sufficiently contact the pores of the adsorbent 9 and effectively adsorb moisture.
In addition, since the convection of the insulating oil 6 is always generated by the heat generated by the center conductor 4 inside the device main body, the insulating oil 6 to which the moisture is adsorbed moves to the entire device, and the insulating oil 6 of the entire device is uniformly removed. The Rukoto.

Therefore, according to the present invention, the water that has entered the insulating oil 6 is constantly adsorbed by the adsorbent 9 during operation,
Regular oil purification work as in the past is not required. Also, the insulating properties of the insulating oil 6 do not deteriorate. Further, the adsorption of the degraded substances (organic ions, sludge, etc.) such as the insulating oil 6 and the insulating paper due to the operation is also performed at the same time, which is also effective in maintaining the insulating performance.

The amount of the adsorbent 9 is determined by the amount of water entering the device, the service life of the device, the adsorbing performance of the adsorbent 9, and the like. It is about 20 to 40% of the weight of the core 5. For this reason, if the whole amount is arranged on the head, the bushing may be top heavy. Therefore, in this embodiment, the container 10 is also provided between the mounting flange 3 and the center conductor 4 as shown in FIG.
The adsorbents 9 housed in are dispersed. The upper and lower surfaces of the container 10 are wire meshes through which the insulating oil 6 can flow, and the inner and outer surfaces are sealed. Convection inside the insulator tube is performed by passing through the inside of the adsorbent 9 arranged at this position, and moisture is adsorbed.

FIG. 3 is a diagram showing a second embodiment in which the present invention is applied to another oil-filled device. In this embodiment, the adsorbent 9 is provided in an oil passage 22 communicating between the conservator 20 and the device main body 21, and the oil flow due to the volume expansion and contraction of the insulating oil 6 passes through the adsorbent 9. Is performed.

FIG. 4 is a diagram showing a third embodiment obtained by improving FIG. In this embodiment, bypass valves 23 and 23 and a bypass passage 24 are provided in the oil passage 22, and when the adsorbent 9 is deteriorated, the valves 23 and 23 are switched to operate the equipment. The adsorbent 9 can be replaced while continuing.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to confirm the effects of the present invention, the first
The oil-filled bushing of the embodiment and the conventional oil-filled bushing without the adsorbent 9 were prepared, and moisture was absorbed into the capacitor core by mixing water during the bushing and repeating heating and cooling. Assuming that the partial discharge starting voltage when moisture is zero is 100, in the conventional oil-filled bushing, when the moisture in the capacitor core is 1% by weight, the partial discharge starting voltage drops to 75, and the moisture in the capacitor core decreases. 2% by weight
In the case of, the partial discharge starting voltage was reduced to 50. On the other hand, in the oil-filled bushing of the first embodiment, even if water equivalent to 3% by weight is mixed, most of the water is adsorbed by the adsorbent 9, so that the partial discharge starting voltage is maintained at 100. Was. The measurement was performed at a temperature of 90 ° C.

[0018]

As described above, the oil-filled electric device of the present invention is configured such that the oil flow due to the volume expansion and contraction of the insulating oil is made to pass through the adsorbent, thereby reducing the water content in the insulating oil. Can be effectively removed. For this reason, there is an advantage that regular oil cleaning work as in the related art is not required, and the insulating properties of the insulating oil are not deteriorated even if moisture invades during long-term use.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first embodiment.

FIG. 2 is an enlarged sectional view of a head.

FIG. 3 is a sectional view showing a second embodiment.

FIG. 4 is a cross-sectional view showing a third embodiment.

[Explanation of symbols]

Reference Signs List 1 air side insulator tube, 2 oil side insulator tube, 3 mounting flange bracket, 4 center conductor, 5 oil immersion paper core, 6 insulating oil, 7 expansion chamber, 8 spring, 9 adsorbent, 10 container, 11 container upper surface, 12 Bottom of container, 13 Spring seat, 14 Gasket, 15 Gasket, 20 Conservator, 21 Equipment body, 22 Oil passage, 23 Bypass valve, 24 Bypass passage

Claims (4)

[Claims] 1. An adsorbent is disposed in an oil passage communicating between an expansion chamber or a conservator and an apparatus main body, so that oil flow due to volume expansion and contraction of insulating oil passes through the adsorbent. An oil-filled electric device containing an adsorbent, characterized in that: 2. The oil-filled electric device containing an adsorbent according to claim 1, wherein the adsorbent is a granular material contained in a container through which insulating oil can flow. 3. The adsorbent-containing oil-filled electric device according to claim 2, wherein a fibrous coating is formed on an inner surface of the container to prevent the fine powder of the adsorbent from flowing out. 4. The adsorbent-containing oil-filled electric device according to claim 1, wherein a bypass valve is provided in the oil passage so that the adsorbent can be replaced.