JPH077606B2 - Overhead power line - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an overhead power transmission line in which a noise-preventing strand is attached to the outer periphery, and particularly to drain water such as rainwater adhering between the strand and the overhead power transmission line. Regarding the improved ones.

[Prior Art] As shown in FIG. 4, a spiral wire 2,
A low wind noise wire wound around 2a or a snow-falling wire is known.

However, if the wire is wound around the wire as described above,
As shown in Fig. 5, when it rains, the water droplets 3 flow down between the electric wire strands 1a, 1a, but because the spiral spiral wire 2 acts as a drainer and winds around the outer circumference of the electric wire. , A wider range of water droplets are collected on the lower surface of the electric wire 1 by the spiral wire 2 to form a large water droplet 3 below the lower surface of the electric wire. For this reason, the potential gradient becomes high, which deteriorates the so-called corona audible noise (AN) characteristic.

Therefore, as shown in FIG. 6, instead of winding the wire around the wire in a spiral shape, the wire 2b in a zigzag shape is provided along the longitudinal direction of the wire 1, and the outer circumference of the wire is less than one turn.
It was conceivable that the strand 2b should be bent and attached to fit the outer shape of the electric wire 1 so as to embrace more than 1/2 turn. According to this, since the wire is not completely wound around the wire,
Since there are few water droplets collected by the wire 2b and the valley of the wire is located at the same level as or above the lower surface of the wire 1, no water drop is formed on the lower surface of the wire, and Capability of capillary action between the wires 2b helped to improve the AN characteristics without forming and attaching large water droplets unlike the conventional example.

However, even if the strands are attached in this way, the role of draining the strands 2b does not disappear, and the water droplets 3 collected in the valleys of the strands 2b due to this draining effect are
It is unavoidable that the wire 2b and the R portion on the surface of the electric wire adhere to the gap formed by the surface tension. As a result, drainage became poor, and AN continued to occur for a long time even after the rain stopped.

[Problems to be Solved by the Invention] As described above, an incompletely wound type wire considered for improving AN characteristics is used in place of the wound type wire which makes a complete turn around the outer circumference of the wire. Even with the overhead power line installed, the AN characteristics were not sufficiently improved because water droplets adhered to the valleys of the zigzag wire. That is, water droplet adhesion is an unavoidable phenomenon when attaching a wire to an electric wire.

Therefore, an object of the present invention is to eliminate the drawbacks of the prior art described above by removing water droplets, to provide a overhead power transmission line capable of further improving water drainage and improving AN characteristics as much as possible. It is in.

[Means for Solving Problems] In an overhead power transmission line of the present invention, a wire to be mounted on the overhead power transmission line is formed in a zigzag shape, and the zigzag width is smaller than the outer circumference of the overhead power transmission line, but is 1/2 circumference or more. To be there. The zigzag-shaped element wire thus formed is arranged along the longitudinal direction of the overhead power transmission line, curved according to the outer shape of the wire, and attached to the outer periphery of the overhead power transmission line except the lower surface. A groove for dropping a water drop is provided inside the bent portion of the zigzag element wire that comes into contact with the electric wire when it is attached.

[Operation] By attaching a zigzag element wire to the outer circumference of the overhead power transmission line except for the lower surface, even if water droplets collect at the bent part of the wire, which is a valley part, they may adhere to or collect at the bent part. Instead, it is dropped and removed from the groove.

[Embodiment] The embodiment of the present invention will be described below with reference to Figs.

FIG. 1 shows an example of an overhead power transmission line of the present invention, in which a wind-sound-preventing or snow-prevention elemental wire 4 is not completely wound around an electric wire 1 but is incompletely wound and sent by overhead. The wires are made up.

The wire 4 is previously formed in a zigzag shape in which the bent portions 4a are alternately provided. The zigzag width is smaller than one circumference of the outer circumference of the electric wire 1, but should be 1/2 circumference or more. The zigzag wire 4 is provided with a groove 5 which will be described later.

In order to attach the zigzag-shaped element wire 4 formed in this manner to the electric wire 1, after the element wire 4 is arranged in the longitudinal direction of the electric wire 1,
Wire 4 that fits the outer shape of wire 1 and holds wire 1
To bend. At this time, the zigzag element wire 4 which is bent and attached to the electric wire 1 is set so as not to come to the lower surface 1b of the electric wire. In this case, the electric wire 1 may be held from the upper side from the beginning, or may be bent and then the strand 4 may be rotated around the axis of the electric wire 1 to avoid the lower surface of the electric wire.

The groove 5 is provided in the gravity direction inside the wire bending portion 4a that comes into contact with the surface of the electric wire when it is mounted. This groove 5
The number may be 1 or 2 or more, and in order to emphasize the effect of the groove 5, it is also possible to provide it in a straight line portion other than the bent portion 4a.
The dimension of the groove 5 is h ≧ 1 mm w ≧ 1 mm from the experimental results shown in FIGS. 2 and 3, where h is the depth and w is the width.

It is desirable to satisfy the value of. That is, the time lapse characteristics of AN are improved by setting w = h ≧ 1 mm, and after 1 minute, AN
The reduction amount reaches -10 dB (Fig. 2). Also, the AN weight loss is w /
h (h = 1 mm) drops sharply from 1 (Fig. 3).

As described above, according to the present embodiment, since the groove 5 is provided inside the bent portion 4a which is the lowermost portion of the wire, the wire flows between the wires, and the draining effect of the wire 4 is exerted. Even if water droplets are collected in the gap between the bent portion 4a and the surface of the electric wire 1 along the wire, the water droplets will be dropped through the groove 5, and therefore, the water droplet will have a surface tension in the gap. As a result, the water will not adhere to the surface and the water will not drain easily, and the occurrence of AN will not continue even after the rain stops.

[Effects of the Invention] In summary, according to the present invention, since a groove for dropping water droplets is provided inside the bent portion of the zigzag element wire that comes into contact with the electric wire, the water droplet is easily formed in the gap between the bent portion and the electric wire. Does not stop, water drainage is further improved, and AN characteristics can be improved as much as possible.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of an overhead power transmission line according to the present invention, in which (a) is a front view, (b) is a sectional view taken along the line BB of (a), and FIG. 2 is a groove. No. 1 and the conventional example in which the bare wire is attached
Fig. 3 shows the characteristics of the AN reduction amount versus elapsed time compared to the overhead ground wire shown in Fig. 3, Fig. 3 shows the characteristics of the AN reduction amount against the groove size of the overhead transmission line shown in Fig. 1, and Fig. 4 shows conventional overhead transmission lines. It is a figure which shows an example, (a) is a front view, (b) is B of (a).
FIG. 5 is a cross-sectional view taken along arrow B, and FIG. 5 is an explanatory view of a water drop adhesion state of the overhead power transmission line shown in FIG. 4, where (a) is a front view and (b).
Is a sectional view taken along the line BB of (a), FIG. 6 is a view showing another conventional example of an overhead power transmission line, (a) is a front view, and (b) is a line BB of (a). FIG. In the figure, 1 is an electric wire, 4 is a wire, 4a is a bent portion, and 5 is a groove.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kenji Yamamoto Inventor Kenji Yamamoto 1500 Kawajiri-cho, Hitachi City, Ibaraki Hitachi Cable Co., Ltd.Toyoura Plant (72) Inventor Katsuo Kimura 1500 Kawajiri-cho, Hitachi City, Ibaraki Hitachi Cable Co., Ltd. Toyoura Factory

Claims (2)

[Claims] 1. A wire which is formed in a zigzag shape and has a zigzag width smaller than the outer circumference of the overhead power transmission line but having a length of 1/2 circumference or more is arranged along the longitudinal direction of the overhead power transmission line and is matched with the outer shape of the wire. Bend it and attach it to the outer circumference except the underside of the overhead transmission line,
An overhead power transmission line, wherein a groove for dropping water droplets is provided inside a bent portion that comes into contact with the electric wire of the zigzag element wire. 2. The overhead power transmission line according to claim 1, wherein the groove dimensions are width w ≧ 1 mm and depth h ≧ 1 mm.