JPH0727741B2 - Lightning protection horn insulator device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention quickly grounds a high voltage due to a lightning strike applied to a power transmission line and shuts off a follow-up arc that occurs thereafter. The present invention relates to a lightning protection horn insulator device capable of preventing a ground fault and capable of withstanding impulses during reclosing due to insulation of an air discharge gap and retransmitting power even if the lightning protection element unit should fail.

[Prior Art] A conventional lightning protection horn insulator device of this type includes a support arm that supports a power transmission line on a support arm of a steel tower so as to be swingable in a line direction and a direction orthogonal to the line direction. The lightning protection insulator is supported at the tip of the, and the discharge side electrode on the power-supply side is connected and supported on the transmission line, and the discharge electrode on the ground side is provided at the end of the lightning protection insulator. There is known a structure in which each is formed into a rod shape and they are opposed to each other with a predetermined air discharge gap.

[Problems to be Solved by the Invention] However, in this conventional lightning protection horn insulator device,
Since the charge-side and ground-side discharge electrodes are each formed in a rod shape, as shown in FIG. 6, the switching impulse characteristics with respect to the gap length of the air discharge gap between both discharge electrodes are low, and a predetermined switching impulse is generated. In order to withstand the above, a large gap length must be secured by using multiple supporting insulators, and the whole device becomes large, which makes it difficult to apply it to an existing device.

The present invention has been made by paying attention to the problems existing in such a conventional technique, and an object thereof is to improve the switching impulse characteristics with respect to the gap length of the air discharge gap. An object of the present invention is to provide a lightning protection horn insulator device that can be downsized as a whole and can be easily applied to an existing device.

[Means for Solving the Problems] In order to achieve the above object, in the lightning protection horn insulator device of the present invention, the power transmission line is orthogonal to the line direction and the line direction via the suspension support insulator on the support arm of the steel tower. The lightning protection insulator is supported at the tip of the support arm, and the discharge electrode on the power-supply side is connected to and supported by the power transmission line, and the discharge electrode on the ground side is connected to the end of the lightning protection insulator. In the lightning protection horn insulator device, the discharge parts of the discharge electrode on the charging side and the discharge electrode on the ground side are formed in a ring shape having arcuate parts, and 1 A book supporting rod is provided in a protruding manner, a mounting plate is provided at a base end portion of the supporting rod, and both discharge portions are opposed to each other with a predetermined air discharge gap.

[Operation] In the lightning protection horn insulator device configured as described above, the discharge portions of the discharge electrodes on the charging side and the grounding side are formed in a ring shape having arcuate portions, respectively, and they are subjected to predetermined air discharge. Since they are opposed to each other with a gap, it is possible to improve the switching impulse characteristics with respect to the gap length of the air discharge gap. Therefore, even if the gap length is set small, it is possible to sufficiently withstand a predetermined opening / closing impulse. Also, one support rod is provided on the outer periphery of the base end of the discharge part,
Since the mounting plate is provided on the support rod, the weight of the discharge electrode can be reduced, the overall size of the device can be reduced, and the work of mounting the discharge electrode can be easily performed.

[Embodiment] An embodiment of a lightning protection horn insulator device embodying the present invention will be described below in detail with reference to the drawings.

As shown in FIG. 1, a suspension metal fitting 2 is attached to a support arm 1 of a steel tower, and a horn mounting metal fixture 4 is connected to the suspension metal attachment 2 via a U clevis 3. A support insulator 5 is suspended and supported on the horn mounting member 4 so as to be swingable in a line direction and a direction orthogonal to the line direction. In this embodiment, a suspension insulator string is formed by connecting a plurality of suspension insulators 6 in series. There is. A horn mounting bracket 7 is connected to the lower end of the support insulator 5, and an electric wire clamp 10 for supporting the power transmission line 9 is mounted on the horn mounting bracket 7 via a connecting link 8. The arcing horns 11 and 12 are attached to the horn mounting brackets 4 and 7, and the arcing horns 11 and 12 reduce the damage caused by the surface flashover of the support insulator 5 at the time of abnormal lightning strike.

A mounting adapter 13 is fixed to the tip of the support arm 1 in a cantilever manner and extends horizontally in the same direction as the line.
A lightning protection insulator (14) is suspended and fixed to the lower surface of the tip of the mounting adapter (13) by a plurality of bolts. The lightning protection insulator 14 includes a pressure-resistant insulating cylinder (not shown) formed in a cylindrical shape by a tension-resistant material such as FRP, and zinc oxide (ZnO) housed in series therein.
A current limiting element with a non-linear voltage-current characteristic
And a pair of cap-shaped grounding and charging side electrode fittings 16 and 17 fitted and fixed to both ends of the pressure-proof insulating cylinder, and a mold rubber 18 provided on the outer periphery of the pressure-proof insulating cylinder. . The mounting adapter 13 and the electrode fitting 17 are provided with arcing rings 19 and 20, respectively, which are opposed to each other, and the arcing rings 19 and 20 reduce damages of the molded rubber 18 when the surface flashes.

The support-side insulator 5 is attached to the charging-side horn mounting bracket 7 below the supporting insulator 5 via a discharging-side discharge electrode 21 and a mounting plate 22. Further, the discharge electrode 23 on the ground side is attached to the electrode-side electrode fitting 17 at the lower end of the lightning protection insulator 14 via the attachment plate 24. The discharge electrodes 21 and 23 on the charging side and the grounding side are arranged to face each other with a predetermined air discharge gap G.

Therefore, the structure of the discharge electrodes 21 and 23 will be described in detail. As shown in FIG. 2, the discharge electrode 21 on the charging side is an elliptical ring-shaped discharge portion having an arcuate portion extending in the line direction.
21a and a support rod 21b welded and fixed to the outer periphery of the base end thereof, and is attached to the mounting plate 22 via the support rod 21b. Further, the ground-side discharge electrode 23 is an elliptical ring-shaped discharge portion 23a having an arc-shaped portion extending in a direction orthogonal to the line direction, and a support rod 2 welded and fixed to the outer periphery of the base end thereof.
3b, and the plate 2 with the above-mentioned attachment through this support rod 23b.
Attached to 4. Then, the discharge parts of both discharge electrodes 21 and 23
21a and 23a are arranged to face each other with the air discharge gap G therebetween.

Here, the curvature RI (see FIG. 3) of the discharge electrode 23 is set so that the air discharge gap G becomes constant when the support insulator 5 is swung in the direction substantially perpendicular to the fulcrum X as a center, and the discharge is performed. electrode
The tip Y of the protrusion 21 protrudes in the line direction from the center of the discharge electrode 23 so that the air discharge gap G becomes constant when the support insulator is swung in the line direction, and rises from the horizontal direction to make the gap G the discharge electrode 23.
Is decided between Y and Y.

Next, the operation of the lightning protection horn insulator device configured as described above will be described.

Now, in this lightning protection horn insulator device, when a surge current caused by a lightning strike is applied to the power transmission line 9, the current flows from the wire clamp 10 to the horn mounting bracket 7 on the voltage applying side,
Discharged in the air gap G between the discharge electrodes 21, 23, and further, the electrode fitting 17, the current limiting element 15 in the lightning protection insulator 14, the electrode fitting
It flows through the support arm 1 of the tower through 16 and the mounting adapter 13, and is discharged from the tower to the ground. Further, the subsequent current generated thereafter is suppressed and cut off by the air discharge gap G between the discharge electrodes 21 and 23 and the current limiting element 15 in the lightning protection insulator 14.

In the lightning protection horn insulator device of this embodiment,
As described above, the discharge parts 21a, 23a of the discharge electrodes 21, 23 on the charging side and the ground side are formed in a ring shape having arcuate parts, respectively, and the discharge parts 21a, 23a are subjected to a predetermined air discharge. Since the air gaps G are opposed to each other with a gap G, even if the gap length of the air discharge gap G is set to be small so that lightning impulses are easily discharged, the resistance becomes high with respect to switching impulses. It becomes difficult to do. By the way, when the device of this embodiment is compared with a conventional device having a rod-shaped discharge electrode, as is clear from FIG. 4, the characteristics of the switching impulse with respect to the gap length of the air discharge gap G is about 30%. Improved.

In addition, in the lightning protection horn insulator device with a transmission voltage of 66 KV,
The ring width D of the discharge parts 21a, 23a of each discharge electrode 21, 23 is 100 mm
Then, when the withstand voltage multiples of the switching impulse were tested with the discharge parts 21a and 23a having a cross-sectional diameter d of 16 mm and 30 mm, the results shown in Table 1 were obtained.

The withstand voltage value of 1 time is Can be obtained at

Further, with respect to the lightning protection horn insulator device having a transmission voltage of 66 KV and 77 KV, the withstanding voltage multiple of the switching impulse was tested with the conventional structure and the embodiment, and the results shown in Table 2 were obtained. I was able to.

As is clear from the above results, in the case of the same transmission voltage system, in the existing insulator device in which the number of insulators connected in the conventional lightning protection horn insulator device is reduced from 6 to 5, the gap of the discharge gap G is increased. Even if the length is reduced, there is no problem because the switching impulse characteristics are almost constant, and as shown in the graph of FIG.
Since the discharge occurs at, it is possible to secure the insulation cooperation against the lightning impulse.

On the other hand, in the configuration of the above embodiment, only the effective length portions of both discharge electrodes 21 and 23 become rectangular ring-shaped discharge portions 21a and 23a,
The other portions become one support rod 21b, 23b, and the mounting plates 22, 24 are connected to the support rod, so that the discharge electrodes 21, 23 can be made smaller and lighter, and the discharge electrode can be easily attached. it can.

The material shape of the discharge electrodes 21 and 23 does not necessarily have to be a columnar shape, and the non-opposing sides may be flat. Ie But you can also press-mold the plate It is also good to reduce the weight. Furthermore, the air discharge gap G
The smaller the value of, the easier it is to cause electrical shortening due to rainwater, icing, etc. Therefore, except for the place where the discharge occurs, use a material such as Teflon or silicon (eg coating, tube coating, etc.) for water repellent treatment. By applying the above, the reliability of the characteristics is further improved.

[Advantages of the Invention] Since the present invention is configured as described above,
The switching impulse characteristics with respect to the gap length of the air discharge gap can be improved, the entire device can be downsized, and it can be easily applied to an existing device.
In addition, the discharge electrode can be reduced in size and weight, and the attachment work can be easily performed, which is an excellent effect.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of a lightning protection horn insulator device embodying the present invention, FIG. 2 is a side view of a discharge electrode on the ground side, and FIG. 3 is a discharge electrode on the charging side and the ground side. FIG. 4 is an enlarged perspective view, and FIG. 4 is a graph showing the characteristics of switching impulse and lightning impulse with respect to the gap length of the air discharge gap. 1 ... Support arm, 5 ... Suspended support insulator, 9 ... Transmission line, 14 ...
Lightning arrester, 21 ... Discharge electrode on the charging side, 21a ... Discharge part, 21b ...
Support rod, 23 ... discharge electrode on the ground side, 23a ... discharge part, 23b ... support rod, G ... air discharge gap.

Claims (1)

[Claims] 1. A power transmission line (9) is swingably supported on a support arm (1) of a steel tower via a suspension support insulator (5) in a line direction and a direction orthogonal to the line direction, and the support arm (1). ) Has a lightning protection insulator (14) supported at its tip, and the power transmission side (9) has a discharge side electrode (21) connected and supported, while the lightning protection insulator (14) has a grounding side discharge at the end. In a lightning protection horn insulator device provided with an electrode (23), the discharge electrode (21) on the charging side and the discharge electrode (2 on the ground side
The discharge parts (21a, 23a) of 3) are formed in a ring shape each having an arcuate part, and one support rod (21b, 23b) is projectingly provided on the outer periphery of the base end of these discharge parts to support the support. A lightning protection horn insulator device characterized in that a mounting plate (22, 24) is provided at a base end portion of a rod, and both discharge portions (21a, 23a) face each other with a predetermined air discharge gap (G).