JPS5973806A - Method of improving energization loss of steel core aluminumtwisted wire - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for significantly improving power transmission loss in steel-core aluminum stranded wires (hereinafter referred to as AC3R) widely used as overhead power transmission lines.

In recent years, the location requirements for power sources in the power transmission field have become more stringent, with the tendency for power sources to become increasingly remote from demand centers, and the power transmission lines that connect them are forced to transmit power over long distances. Naturally, there is a large amount of power transmission loss along the way, which is a serious problem from the perspective of economic circumstances and energy conservation. For this reason, various measures have been taken, such as increasing the pressure to ultra-high pressures, but the reality is that further improvements are desired.

An easy way to improve power transmission loss is to reduce the electrical resistance of power transmission lines. To this end, it is conceivable to (1) increase the conductivity of the conductor or (2) increase the cross-sectional area of the conductor.

The mainstream electric wire used today as overhead power transmission lines is AC8R, which is made by twisting aluminum wire as a conductive member around the outer circumference of a steel core as a tension member. That is extremely difficult. In other words, use it as AC8R,
The conductivity of the EC grade hard aluminum wire used is approximately 62% lA.
C3, but even if you replace it with high purity 99.99% M, it will only be 64% lAC3 at most, and considering the decrease in mechanical strength of the aluminum wire and the increase in price, such a method is It is difficult to hire someone suddenly.

However, no matter how you look at it, method (2) above naturally involves an increase in the outer diameter and weight of AC8R, which causes an increase in repressurization and an increase in sag.It is also necessary to cover the steel tower high and strongly. It's coming.

The present invention has been made in view of the above-mentioned circumstances, and it is possible to significantly reduce the electrical resistance of the ACS R without increasing the outer diameter of the wire, and to greatly improve the current conduction loss [1]. We are trying to provide a way to obtain it.

This will be explained below based on examples.

Standard ACSR specifications are defined by JEC. -If we take an example of 160dAC8R, the steel core is 2.6#1
I11 diameter 7 wires twisted, aluminum wire 2.68 diameter 30 twisted steel core outer diameter 7.8mm, AC8R outer diameter 18.2allll
l Tensile load 6,98Lon, heavyffi 733ka/
km. Naturally, the construction of steel towers and other specifications are determined in accordance with this standard, so major deviations from the standards are not allowed.

What is shown in FIG. 1 is a cross-sectional view of the standard AC8R.
Aluminum wire 2' is placed around the outer periphery of a predetermined steel core 1'.

2'---- are twisted together.

FIG. 2 shows a cross section of AC3R according to the present invention, and the steel core 1 used has a considerably smaller diameter than that shown in FIG.

If the outer diameter of AC8R is kept the same, the cross-sectional area occupied by the aluminum wire will naturally increase accordingly.

Therefore, when looking at the AC8R as a whole, the electrical resistance can be reduced accordingly.

Regarding the 160yJAcsR, the circumstances during this period will be explained with reference to FIG. As mentioned above, the breaking load of the standard 1605I111AC8R is about 7 tons, but the steel wire diameter in this case is 2.6M, and its tensile strength is 135
kg/-.

Now, if we use a steel wire with a strength of 200k (1/d), in order to secure the same breaking load of 7 tons, a diameter of 2.1 mm is sufficient as shown in Figure 5, and a diameter of 22
If it is a steel wire of 0 ka/-, a diameter of 1.9 mm will suffice. Therefore, it will be understood that if such a steel wire is used, a standard breaking load can be ensured even if the cross-sectional area of the steel core is greatly reduced.

However, the present invention is not limited to simply increasing the strength of the steel core and decreasing the cross-sectional area. The space factor of the aluminum portion is increased by the reduction in the steel core diameter. In this case, if only aluminum wires with a circular cross section are twisted together as shown in Figure 2, the space factor will be small and the standard AC8R
It is about 75% at the same outer diameter. Therefore, as shown in FIG. 3 or 4, it is necessary to construct part or all of the aluminum wire with a sector-shaped conductor 3.3. However, if the method according to the present invention is used, the outer diameter of AC8R will not increase even if the aluminum wire is configured with a fan-shaped conductor and the space factor is increased to 85%, and the weight of AC8R will not increase, and the standard weight will be reduced. It can be kept as it is. 5th again
The circumstances during that time will be explained using figures.

As mentioned above, the weight of the standard 160allAC8R is 733K.
g/KRI Teal. In the case of standard wire diameter 2.6#I of steel core with AC3R standard outer diameter, the space factor of aluminum is 8
If it is 5%, the weight will be 792 Ky/Km, which greatly deviates from the standard value. However, according to the present invention, the strength of the steel wire is reduced to 2
If the wire diameter is 00/(y/- and the wire diameter is 2, 1#III+, the space factor of aluminum is 85%, and the weight is still the same as the standard 160dAC8R at °C.Moreover, the electrical resistance in this case is the standard 16041+11AC8R. (7) 0.182
Ω/Km, to: 0.149Ω/Km and 82%
This means that an improvement in conduction loss of nearly 20% has been achieved.

The remarkable effects mentioned above increase the strength of the steel core by an additional 200K.
It goes without saying that the appearance is more noticeable in dogs than in g/III.

To obtain such a steel wire with a strength of 20ONy/- or more, C0.8% or more, Cr0.4-2.0%, SiO
It can be easily obtained by patenting wire drawing processing of 0.08 to 1.5% material.

If fin-like protrusions 4 are formed in the outermost layer of the AC8R according to the present invention as shown in FIG. 4, it is possible to achieve both the anti-snow accretion effect and the low-noise effect.

In the above, 16041111A'C is used as an example.
Although only the case of SR has been described, it goes without saying that the technical idea of the present invention can be applied as is to any other size of ΔC8R.

In order to fully enjoy the effects of the present invention even in such a case, it is desirable that the space factor of aluminum be 85% or more.

Regarding aluminum wires, it is not only applicable to ECUs, but also various heat-resistant aluminum alloys, high-strength aluminum alloys, etc., and in particular, in the case of alloys, the fateful decrease in conductivity can be reduced by There is a sense that this can be compensated for by increasing the rate.

As for the steel core, it goes without saying that it is not limited to ordinary galvanized steel wire, but can also use aluminized steel wire or aluminum-coated steel wire, and by using this type of wire, AC8R's electrical resistance This has the effect of further reducing .

In order to clearly demonstrate the effects of the present invention, detailed comparison values between the conventional example and the present invention are shown in Tables 1 and 2.

If the method according to the present invention were not available, the effect would have been much more remarkable, but it would have been possible to fully clarify it.

As described above, according to the current conduction loss improvement method according to the present invention, in addition to the numerous effects already mentioned, when the operating temperature is the same,
Not only can we expect the effect of increasing the current capacity, but also the industrial value of reducing AC8R's slack and tension by reducing its weight is immeasurable.

[Brief explanation of drawings]

Fig. 1 is a sectional view of a conventional AC8R, Figs. 2 to 4 are sectional views of an AC8R according to the present invention, and Fig. 5 is a 160adAC8R.
FIG. 2 is a diagram showing the relationship between various properties as a result of changes in steel core diameter. 1.1-: 91 cores, 2.2-nialuminum wire, 3: sector-shaped conductor aluminum wire. Indication of 1 item A'1 1982 Patent Application No. 183414
No. 2 Name of the invention Method for improving conduction loss in steel-core aluminum stranded wires 3 Person making the amendment 4 Agent 〒100 5 Date of amendment order - (voluntary) - Subject of amendment (1) Amendment in the scope of claims section Contents (1) The scope of claims is amended as shown in the attached sheet. List of Attached Documents (1) Attachment 1 copy Claim 1 The outer diameter of the steel-core aluminum stranded wire is maintained at approximately the standard outer diameter, the tensile strength of the steel core is actively increased, and the steel-core aluminum stranded wire is The cross-sectional area of the steel core is reduced without reducing the standard breaking load, and the reduction is commensurate with the reduction. [Method for improving conduction loss in steel-core aluminum stranded wire by increasing the cross-sectional area of the aluminum stranded wire layer. 2. A method for improving conduction loss in a steel-core aluminum stranded wire according to claim 1ilJ1, which further actively increases the space factor of the aluminum portion by forming all or part of the aluminum strand into a fan-shaped cross section. 3. The method for improving conduction loss according to claim 1 or 2, wherein the aluminum portion has a space factor of 85% or more.

Claims (1)

[Claims] 1. The outer diameter of the steel-core aluminum stranded wire is maintained at approximately the standard outer diameter, and the tensile strength of the steel core is actively increased, without reducing the standard breaking load of the steel-core aluminum stranded wire. , a method for improving conduction loss in steel-core aluminum stranded wires by reducing the cross-sectional area of the steel core and increasing the cross-sectional area of the aluminum stranded wire layer by an amount commensurate with the reduction valve. 2. A method for improving conduction loss in a steel-core aluminum stranded wire according to claim 1, wherein all or part of the aluminum wire has a fan-shaped cross section to further actively increase the space factor of the aluminum portion. 3. The method for improving conduction loss according to claim 1 or 2, wherein the aluminum portion has a space factor of 85% or more.