JPS6052533B2 - aluminum power line - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is directed to an aluminum power transmission line (hereinafter referred to as "aluminum power transmission line") having a surface quality that does not cause corona discharge, and in particular, to an aluminum power transmission line that does not generate corona noise regardless of the height of the potential gradient. Regarding less aluminum power transmission lines.

Conventionally, ultra-high voltage aluminum power transmission lines connecting between steel towers were
Oils are deposited during the manufacturing and installation processes.

If there is oil on the surface of the aluminum power line, especially when the aluminum power line is connected to an overhead line, it may be exposed to uneven water such as water droplets adhering to the surface during rain or immediately after the rain. The wet condition caused a very loud audible noise due to electrical corona discharge on the surface.

Therefore, conventionally, the oil on the power transmission line was wiped off with a cloth after the transmission line was installed to prevent corona discharge and reduce audible noise, but it is not possible to simply remove the oil. It had little effect.

In addition, wiping off the overhead wires after contacting the wires is extremely difficult because the work is done high up in the air. To solve this problem, conventional systems have been designed to ensure that even if rainwater adheres to the surface of the power transmission line during or after rain, the water droplets will quickly disappear and the surface will be evenly wetted. For example,
Sandblasting is applied to the surface of the wires that make up power transmission lines to disperse water droplets that adhere to the wires during rainfall, thereby preventing the adhesion of large water droplets and improving drainage (Special Publication No. 14185/1983) , A layer of a hydrophilic compound having hydroxyl groups is formed on the surface of the wires constituting the power transmission line to improve water wettability and prevent the formation of water droplets (Special Publication No. 36-14076), surface of aluminum power transmission line The surface is roughened and a hydrophilic film is formed on the surface (
Japanese Patent Application No. 55-3730 (Japanese Unexamined Patent Publication No. 56-134411)), and one in which a protective layer is formed on the hydrophilic film (Japanese Patent Application No. 55-123505 (Unexamined Japanese Patent Application No. 57-4911)).
)) and forms a hydrophobic film on the surface of the aluminum power transmission line,
and its surface is roughened (Patent application 1507-1987)
No. 14 (Japanese Unexamined Patent Publication No. 57-75236)), etc. have been proposed.

These have very good water wettability, allowing water droplets (raindrops) to flow out and drip quickly, and residual water droplets to disappear from the power transmission line surface quickly, effectively preventing the generation of audible noise caused by electrical corona discharge. This is extremely preferable.

However, in a range where the potential gradient on the power line surface is low relative to the shape and number of water droplets adhering to the power line surface, the audible noise is reduced and the potential gradient As the water droplets become larger, the audible noise is reduced on a hydrophobic surface where the number of droplets is large but small.
The conventional type with hydrophilic surface treatment can be used when the surface potential gradient of power transmission lines is extremely high or when there is heavy rainfall.
It is not always possible to expect a sufficient audible noise reduction effect due to corona discharge, and those with hydrophobic surface treatment,
It has both advantages and disadvantages, such as not being able to achieve a sufficient reduction effect when the surface potential gradient is low.

In view of these points, the present invention provides an aluminum power transmission line that can reduce the visible noise caused by corona discharge from high to low surface potential gradients of the power transmission line, thereby solving the above-mentioned drawbacks. , the gist of which is that the outermost wire constituting the aluminum power transmission line is formed of a wire whose surface has been treated to make it hydrophilic and a wire whose surface has been treated to make it hydrophobic. .

Hydrophilic treatment of the surface of the wire can be carried out by spraying with pressurized steam, boiling water, immersion, or anodic oxidation. Alternatively, a hydrophilic film may be formed by a method such as chromate treatment or chemical conversion treatment using the MBV method.

This hydrophilic film may be an anodic oxide film or a chromium oxide film. According to the above method for forming a hydrophilic film,
Bema! It promotes the formation of aluminum hydroxides such as anodic oxide films and anodic oxide films, and also forms hydrated chromium oxides at the same time, which also leads to improved corrosion resistance.

In addition, the hydrophobic treatment on the surface of the wire is performed by forming a hydrophobic film, and examples of the material for the hydrophobic film include resins such as tetrafluoroethylene resin, silicone resin, polyethylene, and polypropylene. Organic acids such as stearic acid, oleic acid, puric acid, caproic acid, lauric acid, butyric acid, perfluorolauric acid, perfluorobutyric acid, and stearimamine, butylamine, hexylamine,
Organic amines such as octadecylamine can be mentioned.

In the case of resin such as tetrafluoroethylene resin, the hydrophobic film can be formed on the surface of the aluminum wire by painting, extrusion,
In the case of organic acids and organic amines, an aluminum wire is placed in a heated steam atmosphere containing these substances, and the surface of the wire is coated with these substances. This can be done by forming a film, or by dissolving an organic acid or organic amine in a solvent and immersing the aluminum wire in the solution to form a film of the organic acid or organic amine on the surface of the wire.

FIG. 1 shows an embodiment of an aluminum power transmission line according to the present invention,
1 is a steel core aluminum stranded wire (hereinafter referred to as ACSR) in which aluminum wires 3 are twisted around a steel wire 2 as a core, and the outermost layer of wires 4 forms a hydrophilic film on its surface. The strand 4a and the strand 4 with a hydrophobic film formed on the surface of the strand 4a
b.

Although it is preferable that the wires 4a and 4b are arranged alternately as shown in the figure, they do not necessarily have to be arranged alternately.

Further, the formation of the hydrophilic film and the hydrophobic film on the wires 4a and 4b is performed by the method described above.

Figure 2 shows the values of the corona noise level for 3 minutes after the water supply stopped, using a cylindrical corona gauge, to measure the corona noise level of the product according to the present invention and the comparative product, using a cylindrical corona gauge while injecting water at a rate of 3''/h. This is a graph showing the results of measurements over a potential gradient of 10 to 28 K/Cm. A is a graph showing the results of measurements taken over a potential gradient of 10 to 28 K/Cm. In the case of the sample of the product of the present invention, in which aluminum wires with a so-called aluminum oxide film formed thereon and aluminum wires coated with tetrafluoroethylene resin on the surface are arranged alternately, B is 810iACSR. In the case of an untreated comparative product sample, C is a comparative product sample with a hydrophilic film formed on the surface of 810m1tACSR, and D is 810TdACSR.
In the case of a comparative sample with a hydrophobic film formed on the surface of SR,
are shown respectively.

According to this graph, the corona noise level of untreated B is generally high from the low maximum surface potential gradient of 10 KV/C7l to the high 2 S/d, and that of C with a hydrophilic film on its surface. The formed ones show a low corona noise level in the range of 10KV/d to 1V/d, etc., where the maximum surface potential gradient is low, but in the range of 18KV/d to 28K/d, etc., where the maximum surface potential gradient is high.
A range such as Cm shows a high corona noise level, and as the potential gradient increases, it becomes less effective in reducing audible noise due to corona discharge. Low 10KV/Cm~
In the range of 18KV/Cm etc., it shows a high corona noise level and has a high potential gradient of 20KV/Cm~2? V/C! In the range R etc., the corona noise level is low, and in the range where the potential gradient is low, it is shown that there is no effect in reducing audible noise due to corona discharge. from low 10KV/Cm to high 28KV
/Cm, the corona noise level is low, indicating that it is generally effective in reducing audible noise due to corona discharge regardless of the height of the potential gradient.

This is because the aluminum power transmission line according to the present invention has an aluminum wire constituting its outermost layer made up of a wire having a hydrophilic film formed on its surface and a wire having a hydrophobic film formed on its surface. It is thought that this is because the disadvantages of the hydrophilic treatment and the disadvantages of the hydrophobic treatment are reduced, and the disadvantages are reinforced by each other.

It should be noted that substantially the same effect results were obtained with the hydrophilic film and hydrophobic film other than the hydrophilic film and hydrophobic film of the above-mentioned Example.

In addition, the hydrophilic film and hydrophobic film on the 810TdACSR surface of Samples C and D exhibited almost the same effect regardless of the method used to form the film of any material in the case of the aluminum wire. , I purposely did not give an example.

As described above, the aluminum power transmission line according to the present invention is useful for reducing audible noise due to corona discharge from low to high surface potential gradients.

Incidentally, in the present invention, the surface of the aluminum power transmission line may be roughened, since the effect becomes even higher when the surface is roughened.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an example of the present invention, and FIG. 2 is a graph showing the results of an effect test. 1... Steel core aluminum stranded wire (ACSR), 2...
...Steel core, 3...Aluminum wire, 4...
...The outermost layer of wire, 4a...The wire having a hydrophilic film formed on its surface, 4b...The wire having a hydrophobic film formed on its surface.

Claims (1)

[Claims] 1. An aluminum power transmission line characterized in that at least the outermost layer of the aluminum wire constituting the aluminum power transmission line is formed of a wire whose surface has been treated to make it hydrophilic and a wire whose surface has been treated to make it hydrophobic.