JP2526658B2 - Wind noise countermeasures for multi-conductor transmission lines - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention has been improved to realize both reduction of wind noise and reduction of audible noise (hereinafter referred to as AN) level in a multiconductor transmission line. Wind noise countermeasures.

[Prior Art] In recent years, the transmission voltage of an overhead power transmission line has tended to become extremely high voltage, and from the transmission of 500,000 V to the UHV transmission of 1 million V class is about to be realized.

As the transmission voltage of the overhead transmission line becomes extremely high, the potential gradient at the outer periphery of the line becomes extremely high and AN increases, so the transmission line is made into a multiconductor, and in the above UHV transmission,
A very large number of conductor arrays, ~ 10 conductors, are about to be adopted. However, if the power transmission line is made multi-conductor and the number of conductors is increased, the wind noise generated by the electric wire due to wind pressure is correspondingly large, and the influence on the social environment becomes a problem.

As shown in FIGS. 5 and 6, the overhead power transmission line is composed of a steel core aluminum stranded wire in which an aluminum element wire 1b is twisted around the outer circumference of a steel core 1a. An electric wire is constructed. In order to reduce the wind noise of such a power transmission line, it is already widely practiced to wind the spiral rod 2 around the outer periphery of the conductor 1 as shown in FIGS.

On the other hand, looking at the arrangement state of the element conductors of the multi-conductor power transmission line described above, it is possible to use the 4th line at the time of overhead line construction and the stability of space work during construction or maintenance. As shown in the figure, it is usual that a pair of two conductors are present in the horizontal direction and the element conductors are arranged so as to be concentric. That is, FIG. 4 (a) shows the conductor arrangement in a 4-conductor transmission line, FIG. 4 (b) shows the conductor arrangement in a 6-conductor transmission line, and FIG. 4 (c) shows the conductor arrangement in an 8-conductor transmission line. It is shown.

[Problems to be Solved by the Invention] When wind blows on a multi-conductor transmission line having a conductor array as described above, assuming that wind blows from the direction of arrow V in FIG. There is a difference in the wind pressure load received by the element conductors on the left side and the right side of the respective two conductors. That is, the leeward conductor is affected by wind turbulence due to the windward conductor. Therefore,
Even when wind noise is reduced by winding the spiral rod described above, it is necessary to adopt a winding method capable of coping with such turbulence of the wind.

FIG. 10 is a diagram showing the wind noise reduction effect when the spiral rod 2 is wound around the conductor 1.
The results of measuring the wind noise reduction situation at a wind speed of 20 m / s using a wind tunnel using a 0 mm ² ACSR, winding a spiral rod whose diameter is shown on the horizontal axis as shown in the cross-sectional view in the figure, are shown. It is a thing.

As can be seen from FIG. 10, in the case of a single conductor, wind noise is markedly reduced as shown by a curve R by winding one spiral rod around the outer circumference of the wire. However, like the multi-conductor transmission line described above, two conductors that form a pair are horizontally arranged in parallel,
When the wind is sent in the direction parallel to this, the effect of reducing the wind noise is hardly recognized as is apparent from the curve P by simply winding one spiral rod.
It is considered that this is because the leeward conductor is affected by the turbulence of the wind due to the upwinding conductor described above.

However, even with such a two-conductor arrangement of pairs, when two spiral rods are wound at a position facing the outer circumference of the wire instead of one, a clear wind as shown by the curve Q in FIG. Sound reduction effect comes to be recognized. Therefore, in the power transmission line having the multi-conductor array as described above with reference to FIG. 4, the method of winding the spiral rods 2, 2 around the outer periphery of the conductor 1 as shown in FIG. 5 or 6 is adopted. It has been done.

However, the wind noise is reduced by winding the spiral rod 2 as described above, but a protrusion is formed by the spiral rod on the outer circumference of the power transmission line, and concentration of the potential gradient occurs on the protrusion portion. It causes deterioration of AN characteristics.

Figure 8 shows the same 810mm ² AC used in the experiment of Figure 10 above.
It is a diagram showing the results of AN level measurement using SR with a potential gradient Gmax = 15 kv / cm and rainfall of 10 mm / hr. Each of the horizontal axes (a), (b), (c), (d) ) And (e) show the cross-sectional structure of the electric wire, and the vertical axis plots the AN level corresponding to the electric wire of each cross section from (a) to (e).

In the case of FIG. 10, it has been confirmed that wind noise is significantly reduced by winding two spiral rods facing the two conductors of the pair forming the multi-conductor transmission line. When it has a cross-sectional structure ((d) in Fig. 8),
As can be seen from FIG. 8, the AN level shows the maximum value. With this, even if the wind noise can be significantly reduced, the AN level becomes too high, which is too problematic for application to ultra high voltage transmission lines.

However, even when the spiral rod is wound around the conductor in the same manner, if two spiral rods 2 are closely attached to the conductor 1 as shown in FIG. (Fig. 8 (e)), AN level is the case where a single spiral rod is wound oppositely to conductor 1 (Fig. 8 (d)).
The AN level is about 7 dB lower than that of.

Figure 7 shows the same 810 m used in the experiment in Figure 8.
Wind a spiral rod with a rod diameter of 7 mm and a winding pitch of 400 mm around the m ² ASCR in the state shown in Figures (a) to (e),
FIG. 6 is a diagram showing the results of plotting the occurrence status of wind noise at a wind speed of 20 m / s, which is obtained by forming six conductors having a conductor arrangement as shown in FIG. 4 (b).

It is well understood from this figure that wind noise is reduced by winding the spiral rod, while the degree of reduction of the wind noise level greatly varies depending on the winding condition of the spiral rod.

Comparing this with the AN level measurement result of FIG. 8 described above, it can be seen that the AN level characteristic and the wind noise reduction characteristic do not always show the same tendency even if they have the same sectional configuration. Therefore, by selecting an appropriate spiral rod winding state, it is possible to think of an AN cooperative wind noise countermeasure that can significantly reduce the AN level while reducing the wind noise level as much as possible.

In view of the above situation, an object of the present invention is to provide an AN cooperative wind noise countermeasure method in a multi-conductor transmission line capable of suppressing an increase in AN level as much as possible while reducing wind noise. To do.

[Means for Solving the Problems] According to the present invention, an array of element conductors of a multi-conductor transmission line configured by a plurality of element conductors formed by winding a spiral rod is arranged in a direction substantially parallel to the wind direction. There is a pair of conductors and there is a single conductor in a position orthogonal to it, and the conductors are arranged in a positional relationship, and the conductor is wound around the above-mentioned monomer rather than the number or diameter of spiral rods wound around the conductor. The number of spiral rods or the diameter thereof is smaller or smaller.

[Operation] If the arrangement of the element conductors of a multi-conductor transmission line is not arranged so as to be a combination of two horizontal conductors but a part of them is arranged as a single conductor, and considering wind noise, Fig. 10 As can be seen from the figure, the single conductor portion has the maximum wind noise reduction even though the number of spiral rod windings is small, and in such a spiral rod winding mode, the cross section (b) in FIG. As shown, since the AN level can be kept within a relatively small range, it is possible to effectively reduce wind noise and minimize the AN level as a general result of the entire multiconductor transmission line.

[Examples] Hereinafter, the present invention will be described with reference to Examples.

FIG. 3 is an explanatory view showing a case where a multiconductor power transmission line is installed in an array state according to the present invention.

In the figure, the arrow V indicates the direction in which the wind blows,
Since the wind normally blows in the horizontal direction, the arrow V eventually indicates the horizontal direction. However, in a specific place where the wind blows up from an oblique direction, such as a valley, this arrow V means the direction in which the oblique wind blows.

FIG. 3 (a) shows the case of a four-conductor transmission line, in which a pair of conductors are arranged in the direction of arrow V, that is, in the normal horizontal direction.
The monomer is arranged above and below the line in such a manner that one monomer is arranged in each line. Moreover, FIG.
And (c) shows the case of 8 conductors respectively. In addition to the conductor arrangement which becomes a pair in the horizontal direction among these conductors, the arrangement is such that the monomers are arranged above and below each other. There is a feature of the invention.

The above shows the case where there is an even number of conductors.
The conductor arrangement according to the present invention is possible even when the number of conductors is odd. That is, for example, in the case of three conductors, FIG. 11 (a)
The base position of the equilateral triangle should be in the direction of the arrow V so that a single conductor exists at the apex position.
When there are a large number of conductors such as conductors and nine conductors, the conductor arrangement according to the present invention can be obtained by arranging a single conductor as shown in FIG. 11 (b), for example.

FIG. 1 shows the wind noise according to the present invention in a 6-conductor power transmission line having the above-mentioned arrangement relationship of FIG. 3 (b) in which two conductors of a pair are horizontally arranged in two rows and single conductors are arranged above and below the conductor. It is explanatory drawing which shows the case where countermeasures are taken.

Two spiral rods 2 closely wound are wound around the two parallel conductors so as to face each other, but the single conductors arranged at the upper and lower positions have the spiral rods 2 closely attached to each other. It shows the case where only the strip is wound. Considering the number of spiral rods, four spiral rods are wound around the parallel-arranged conductor, while half of the spiral rods are wound around the upper and lower single conductors. Become.

FIG. 9 is a diagram showing a wind tunnel test result in a 6-conductor transmission line having conductor arrangements shown in (A) to (D). The diameter of the spiral rod in (B) and (D) in which the spiral rod 2 is wound around the conductor 1 is 7 m.
m, the winding pitch is 40 mm, and the wind speed is 20 m / s.

The transmission line (A) is a conventional example without wind noise countermeasures, the same (B) is a conventional example with wind noise countermeasures, and the same (C) is a conductor array according to the present invention and an example of an arrangement without wind noise countermeasures, and (D) shows the arrangement examples according to the present invention shown in FIG. 1, respectively.

As is clear from FIG. 9, the wind noise level was significantly reduced in both (B) and (D) where the wind noise countermeasure was taken, compared to the case where the wind noise countermeasure was not taken (A) and (C). The wind noise countermeasure effect is clearly recognized, and the effect is not significantly different in both the conventional example (B) and the present invention (D).

However, when the AN level is observed, the AN level is obviously smaller in the configuration of (c) than in the configuration of (e) of FIG. 8 as is clear from FIG. 8 described above. Compared with FIG. 9 (B) in which all six element conductors have the configuration of FIG. 8 (e), in FIG. 8 (D) according to the present invention, the element conductor has the configuration of FIG. 8 (e). Is reduced to four, and the remaining upper and lower single conductors have the configuration shown in FIG. As a result, the configuration of (D) has two fewer element conductors of the configuration of FIG.
Since the element conductor having the configuration of FIG. 8C is arranged instead of the element conductor, the number of element conductors that adversely affect the AN level is reduced by two, and the element conductor having the AN level reduction effect is reduced. Since it is increased by two, the synergistic effect shows that the AN level of (D) according to the present invention is significantly suppressed as compared with the conventional example of FIG. 9 (B). Of. Therefore, the (D) according to the present invention has a significant wind noise reduction effect and at the same time can effectively improve the AN characteristics.
It can be said that it is a cooperative wind noise countermeasure.

In addition, in the case of FIG. 1, the number of spiral rods wound around the upper and lower single conductors is reduced, but the number of spiral rods of the upper and lower single conductors is reduced at the same time as the diameter of the spiral rods is reduced. May be wound using a spiral rod smaller than the diameter of the spiral rod wound around the parallel two conductors.

Figure 2 is one wound spiral rod 2a and below the single conductor at 6 conductor, yet were selected smaller than the diameter d ₂ of the spiral rod 2b which is wound the diameters d ₁ parallel second conductors example Is shown.

According to this structure, the electrical characteristics become more advantageous as the molds of the upper and lower spiral rods become thinner, and the AN level reducing effect can be made more remarkable.

[Effects of the Invention] As described above, according to the wind noise countermeasure method of the present invention, the following excellent effects can be exhibited.

(1) The AN level can be significantly reduced,
In particular, since the occurrence of secondary obstacles when taking measures against wind noise for ultra-high voltage transmission lines with a large number of conductors can be eliminated by doing so, take measures against wind noise on 1 million V class transmission lines. It will be possible to build.

(2) The required number of spiral rods is reduced, and the material cost can be reduced accordingly.

(3) From the top of the wind load, the component of the spiral rod wound around the single conductor is much smaller than the component of the spiral rod on the side of the two parallel conductors. Will be reduced.

[Brief description of drawings]

FIGS. 1 and 2 are explanatory views showing two different embodiments in which the wind noise countermeasure according to the present invention is applied to a 6-conductor transmission line, and FIG. 3 is an arrangement of element conductors of a multi-conductor transmission line according to the present invention. Fig. 4 is an explanatory view showing the state of the conventional arrangement of multiconductor transmission lines, and Figs. 5 and 6 are two examples in which a spiral rod is wound around an aluminum steel wire. Fig. 7 is a diagram showing the relationship between the conductor cross-sectional structure and the wind noise level, Fig. 8 is a diagram showing the relationship between the conductor cross-sectional structure and the AN level, and Fig. 9 is a 6-conductor transmission line. Fig. 10 is a diagram showing the relationship between the conductor arrangement and its configuration and the wind noise level, Fig. 10 is a diagram showing the relation between the conductor configuration and arrangement state and the wind noise reduction effect, and Fig. 11 is a 3-conductor transmission line and 7 conductors. It is explanatory drawing which shows the conductor arrangement based on this invention in a power transmission line. 1: Elementary conductor, 2: Spiral rod.

Claims (3)

(57) [Claims] 1. An array of element conductors of a multi-conductor transmission line formed by winding a spiral rod and comprising a plurality of element conductors arranged in a direction substantially parallel to the wind direction and having a pair of conductors and orthogonal thereto. Are arranged so that there is a single conductor in the position where the spiral conductor is wound, and the winding state of the spiral rod is wound on the conductor which becomes the single conductor more than the number of spiral rods wound around the conductor which becomes the parallel arrangement. Wind noise countermeasure method for multi-conductor transmission lines configured to reduce the number of spiral rods that are turned. 2. An array of element conductors of a multi-conductor transmission line formed of a plurality of element conductors formed by winding a spiral rod, arranged in a direction substantially parallel to the wind direction, and having a pair of conductors, and orthogonal thereto. Are arranged so that there is a single conductor at the position, and the spiraled state of the spiral rod is wound around the conductor that becomes the single conductor rather than the diameter of the spiral rod that is wound around the conductor that becomes the parallel arrangement. Wind noise countermeasure method for multi-conductor transmission lines, which is configured so that the diameter of the spiral rod that is turned is smaller. 3. An array of element conductors of a multi-conductor transmission line formed of a plurality of element conductors formed by winding a spiral rod, is lined up in a direction substantially parallel to the wind direction, and a body conductor is orthogonal to that. The conductors are arranged so that there is a single conductor at the position where the spiral rods are wound, and the spiral conductors are wound so that the conductors become the single conductors more than the number and diameter of the spiral rods wound around the conductors. Wind noise suppression method for a multi-conductor transmission line configured so that the number and diameter of spiral rods wound around the coil are smaller.