JP2801387B2 - Three-phase transmission line - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a three-phase power transmission line in which an inter-phase spacer is configured and mounted in a three-jump resistant manner.

2. Description of the Related Art When a wind blows against icing snow on a power transmission line to generate lift and generate galloping vibration that vibrates up and down, electric wires of different phases arranged above and below come into contact with each other to cause an interphase short circuit.

This snow accretion rotates along the wire peripheral surface while sliding along the stranded wire of the electric wire surface, and also twists the electric wire. Galloping vibration develops into a large-amplitude self-excited vibration when the period in which the snow-covered electric wire is vibrated up and down by the strong wind coincides with the period in which the electric wire is twisted and rotated.

For this reason, as a conventional method of preventing interphase short-circuiting caused by vertical oscillation of galloping of a transmission line, there is a method of controlling a twisting cycle of the electric wire to attach a damper to the electric wire, or a method of mounting a damper on the upper and lower sides. A method has been implemented in which the wires of different phases are fixed with an interphase spacer to limit the amplitude of the galloping vibration.

[Problem to be Solved by the Invention] In the case of the method of mounting a damper for controlling the twisting period of the electric wire to suppress galloping, the galloping having a small lateral amplitude compared to a vertical amplitude without twisting is used. Has proven ineffective.

In the method of limiting the amplitude of galloping vibration by fixing the electric wires of different phases with interphase spacers, insulating interphase spacers having insulators attached to rods are used. In many cases, it cannot be installed because the strength of the wire support is insufficient. For this reason, there is an interphase spacer whose weight is reduced by using a polymer insulator such as silicon rubber or ethylene propylene rubber instead of a porcelain insulator, but this has a problem in long-term use because of its difficulty in tracking resistance.

In addition, this type of interphase spacer has a drawback in that when the transmission line develops snow and develops into a cylindrical snow, and when this falls off at the same time, a three-jump in which the electric wire jumps up occurs, the spacer breaks due to eccentric buckling stress.

On the other hand, a configuration in which a conductor holding portion is rotatable in a multi-conductor spacer is disclosed in Japanese Utility Model Laid-Open Publication No. 50-59090 and Japanese Patent Publication No. 48-582.
As is known from US Pat. No. 5,838,849, this is not tolerable by the spacers against three jumps.

The present invention is designed to prevent the occurrence of a contact short-circuit accident and the damage of the inter-phase spacer even when the transmission line jumps three-dimensionally.
The purpose is to install an interphase spacer on a phase transmission line.

Means for Solving the Problems In order to achieve the above object, the present invention provides an inter-phase spacer provided with wire gripping portions at both ends of an insulated rod, in which a three-phase transmission line having an upper, middle, and lower phase is provided. In a three-phase power transmission line attached to an electric wire, that is, between an upper-phase electric wire and a middle-phase electric wire and between a middle-phase electric wire and a lower-phase electric wire, one of the electric wire gripping portions at both ends of the insulating rod of the interphase spacer is loosely gripped, and the other is a loosely gripped portion. By constituting the fixed grip portion, this loose grip portion is attached to the upper wire of each phase and loosely gripped, and the fixed grip portion is attached to the lower wire and fixed, so that upper, middle, The torsional stiffness of each lower phase electric wire is set to increase in the order of upper phase <medium phase ≦ lower phase.

[Operation] The loose gripping portion loosely grips the electric wire so as to be able to rotate to some extent with respect to the electric wire without fixing to the electric wire. The fixed holding portion is fixed to and held by the electric wire.

Of the upper, middle, and lower phase wires, only the loose gripping part is attached to the upper phase wire, the gripping force is laze, and there is no resistance to twisting of the wire.
The smallest of the middle and lower three phases.

For lower-phase wires, the loose grip at the upper end of the spacer to which the fixed grip at the lower end is attached is attached to the upper middle-phase wire. , The torsional stiffness of the lower-phase electric wire is the largest among the three phases of upper, middle, and lower, or almost equal to the middle phase.

As for the middle-phase electric wire, the fixed grip of the interphase spacer between the upper-phase wire and the loose gripper of the interphase spacer between the lower-phase wire are attached. The torsional stiffness of the upper phase wire and the lower phase wire is in the middle, and the torsional stiffness of the middle phase wire is approximately the same as the maximum torsional stiffness of the lower phase wire with respect to the minimum torsional stiffness of the upper phase wire. It will be.

That is, the torsional rigidity of the upper, middle, and lower three-phase wires increases in the order of upper phase <middle phase ≦ lower phase.

In addition, since the electric wire snows while rotating while sliding on the surface of the electric wire, the electric wire is twisted and develops into a snowy snow. Therefore, as the torsional rigidity of the electric wire is smaller, the electric wire is more likely to be twisted and the snow accretion is more easily developed. Accordingly, of the upper, middle, and lower three-phase electric wires, the upper-phase electric wire having the lowest torsional rigidity is most likely to develop snow.

If the snow on this wire develops into an overly cylindrical shape, it will fall due to its own weight and cause a three jump, but the three jumps will occur in the upper, middle, and lower phases of the upper phase, where the snow is most developed. Will occur first on the wire.

That is, as described above, by increasing the torsional rigidity of the upper, middle, and lower three-phase electric wires in the order of upper phase <medium phase ≦ lower phase, snow accretion of the upper phase electric wires can be developed most greatly. Thus, it is possible to cause a sleep jump first.

Even if the upper-phase electric wire jumps upward in a three-jump manner, there is no other electric wire to contact thereabove, so that no contact short-circuit accident occurs.

At the same time as the upper-phase electric wire jumps up by a three-jump, the middle-phase electric wire is pulled upward by the interphase spacer attached to the upper-phase electric wire, and is further lowered by the interphase spacer attached to this medium-phase electric wire. Since the electric wires of the phase are also pulled upward, the impact of these impacts causes the snow of the electric wires of the middle phase and the lower phase to fall in a small snowfall that does not greatly develop. In this small snowfall, even if the electric wire is shaken, it does not result in a large sleep jump, so that no contact short-circuit accident with another phase electric wire occurs.

In addition, although a tensile force is applied to the interphase spacer, one of the electric wire gripping portions is a loose gripping portion, so that the bending force applied to the spacer is extremely small and no eccentric bending stress acts, so that the spacer does not break. .

Examples Examples of the present invention will be described below with reference to the drawings. FIG. 1 shows that an interphase spacer I is attached to an upper phase wire A and a middle phase wire B of a three-phase transmission line of a span, and an interphase spacer II is attached to a middle phase wire B and a lower phase wire C at an interval l. An embodiment in which is attached.
In each of the interphase spacer I between the upper phase and the middle phase and the interphase spacer II between the middle phase and the lower phase, 1 is an insulating rod made of a porcelain insulator, a polymer-polymer insulator series, an FRP rod, and the like, and 2 and 3 are provided at both ends of the insulating rod. 2 is a loose grip,
3 is a fixed holding part.

Both of the interphase spacers I and II attach the loose grip 2 to the upper electric wire and the fixed grip 3 to the lower electric wire. The interphase spacer I has the loose grip 2 on the upper electric wire. The fixed holding part 3 is attached to the phase electric wire A, and is attached to the lower middle-phase electric wire B. Similarly, the loose grip portion 2 of the interphase spacer II is attached to the upper middle-phase electric wire B, and the fixed grip portion 3 is attached to the lower lower-phase electric wire C.

FIG. 2 shows an example of the structure of the interphase spacers I and II.
Comprises a clamp 4, a collar 10 fixed to the clamp 4, and a loose clamp 17 rotatably mounted on the outer periphery of the collar 10.

FIG. 3 shows this loose gripping portion 2. The clamp 4 connects the two semicircular halves 5, 6 with a hinge 7, and fixes both lower portions 8 thereof with a spring, a washer and a T-bolt 9 for fixing. The color inside the two semicircular halves 5, 6
Fix 10

The collar 10 is composed of a half-circular cylindrical body 11 and 12 and has a flange 13 at the left end, a flange 14 at the middle, and a flange 15 at the right end (15 is a second illustration). The right half portions of the semicircular cylinders 11 and 12 are fixed to the inside of the semicircular halves 5 and 6 of the clamp 4 with screws or the like, and the semicircular halves 5 and 6 of the clamp 4 are opened to open the half of the collar 10. The circular cylinders 11 and 12 are also opened. The upper electric wire D is sandwiched between the two semicircular cylindrical bodies 11 and 12 of the collar 10,
By closing the semicircular halves 5 and 6 of the clamp 4 and tightening and fixing them with the bolts 9, the upper electric wire D is fixed and attached in the circular hole 16 in the collar 10.

As shown in FIG. 3, the loose clamp 17 has the circular hole 22 sandwiching the collar 10 between two semicircular portions 18 and 19 having an inner diameter slightly larger than the outer diameter of the collar 10. It is fixed by a boltless tightening device 21. As a result, the loose clamp 17 is rotatably mounted on the outer periphery of the collar 10 on the side of the clamp 4 fixed to the upper electric wire D, and the loose gripping portion 2 composed of the clamp 4, the collar 10, and the loose clamp 17 is attached to the upper electric wire. It will be loosely attached to D to be able to rotate to some extent. 23 designates this loose gripping part 2 as an insulating rod 1
Bolt to be attached to the upper end of

The fixed gripping portion 3 at the lower end of the insulating rod 1 is constituted by a clamp which is fixed across the electric wire, and is fixed to the lower electric wire E for mounting.

In addition, the loose grip part 2 is not limited to the above-described configuration, and may be configured to be rotatable with respect to the electric wire and loosely grip the electric wire.

The interphase spacer provided with the loose gripping portion 2 and the fixed gripping portion 3 is mounted on the upper phase electric wire A and the intermediate phase electric wire B as shown in FIG. When the loose grips 2 and 2 of the interphase spacer II are attached to the upper wires A and B, and the fixed grips 3 and 3 are attached to the lower wires B and C, the upper-phase wire A, the middle-phase wire B, and the lower The torsional rigidity of the phase wire C increases in the order of upper phase A <medium phase B ≦ lower phase C.

When the upper, middle, and lower three-phase electric wires A, B, and C receive a cross wind in the direction of the arrow as shown in FIG. 4 (a), the middle-phase electric wire B is formed as shown in FIG. It is twisted in the range 1 shown in FIG. If all the gripping portions of the interphase spacers I and II are fixed gripping portions, the wires may be damaged, so that it is necessary to greatly separate the interphase spacers I and II by a certain distance or more. , II need not be so far apart.

In the above-mentioned embodiment, the embodiment in which the inter-phase spacers are attached one by one between the upper, middle and lower phases is shown. However, a plurality of inter-phase spacers may be attached at appropriate intervals as needed.

[Effects of the Invention] As described above, the present invention loosely grips the upper phase wire and the middle phase wire and the wires above the middle phase wire and the lower phase wire with the loose gripping portion of the interphase spacer. Since the torsional stiffness of the upper, middle, and lower phase wires is increased in the order of upper phase <medium phase ≤ lower phase by gripping the wire on the side with the fixed gripper, the wire in which the largest It can be specified as the uppermost electric wire, and even if it is a three-jump, it does not cause a contact short-circuit accident with the other-phase electric wire, does not damage the spacer, and can withstand the three-jump.

[Brief description of the drawings]

FIG. 1 is a view showing one embodiment of the present invention, FIG. 2 is a front view of an interphase spacer, FIG. 3 is an exploded explanatory view of a loose grip,
FIG. 4 is a view for explaining torsion of the electric wire due to wind. 1; insulating rod 2; loose grip 3; fixed grip 4; upper wire 5; lower wire A; upper phase wire B; middle phase wire C; lower phase wire

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-64-8814 (JP, A) JP-A-1-214209 (JP, A) JP-A-2-74116 (JP, A) JP-A-2- 95112 (JP, A) JP-A-2-254916 (JP, A) JP-A-2-91415 (JP, U) JP-A-2-91418 (JP, U) JP-B-49-25993 (JP, B1) (58) Field surveyed (Int.Cl. ⁶ , DB name) H02G 7/00-7/22

Claims (1)

(57) [Claims] 1. A three-phase transmission line in which interphase spacers having wire grippers provided at both ends of an insulating rod are attached to upper, middle, and lower phase wires, respectively. One of which is a loose grip, the other is a fixed grip, and the loose grip is attached to the upper wire of each phase and the fixed grip is attached to the lower wire,
A three-phase transmission line, wherein the torsional stiffness of each of the middle and lower phase electric wires is increased in the order of upper phase <medium phase ≦ lower phase.