JPH0743974B2 - 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 impulse voltage at the time of reclosing and re-transmitting power even if the lightning protection element unit should fail.

[Prior Art] As a conventional lightning protection horn insulator device of this type, a power transmission line is supported on a support arm of a steel tower through a support insulator, and a lightning protection insulator is supported on a tip end of the support arm to impose the power transmission line. The discharge electrode on the charging side is connected and supported, and the discharge electrode on the grounding side is provided at the end of the lightning protection insulator.The discharge electrodes on the charging side and the grounding side are formed in rod shapes, respectively, and they are discharged in the predetermined air. A configuration in which they are opposed to each other with a gap is known.

[Problems to be Solved by the Invention] However, in this conventional lightning protection horn insulator device,
Since the discharge electrodes on the charging side and the grounding side are each formed in a rod shape, as shown in FIG. 17, 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. Therefore, a large gap length must be secured in order to withstand a large number of supporting insulators, which makes it difficult to apply it to an existing device due to the large size of the entire 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, a power transmission line is supported by a support arm of a steel tower via the support insulator, and a tip portion of the support arm is provided. In the lightning protection horn insulator device, which supports a lightning protection insulator, and which connects and supports a discharge electrode on the power-supply side to the power transmission line, and a discharge electrode on the ground side is provided at the end of the lightning protection insulator, At least the discharge parts of the discharge electrode and the discharge electrode on the ground side are formed in an arc shape which is convex to each other, and these discharge parts are opposed to each other with a predetermined air discharge gap.

Each of the discharge parts may be formed in a semi-circular shape, and both ends thereof may be connected by a closed loop forming part so that both members electrically form a semi-circular closed loop.

[Operation] In the lightning protection horn insulator device configured as described above, the discharge parts of the discharge electrodes on the charging side and the grounding side are formed in arcuate shapes that project from each other, and they have a predetermined air discharge gap. Since they are opposed to each other, the switching impulse characteristics with respect to the gap length of the air discharge gap can be improved. Therefore, even if the gap length is set small,
It can sufficiently withstand a predetermined opening / closing impulse, and can reduce the size of the entire apparatus.

When a semi-annular closed loop is electrically formed by the discharge part and the closed loop forming part, a small discharge electrode has an electric field relaxation action similar to that of the annular shape.

[Embodiment] Hereinafter, a first embodiment of a lightning protection horn insulator device embodying the invention of claim 1 will be described in detail with reference to FIGS. 1 to 3.

As shown in FIG. 1, a support insulator 2 made of a long insulator is suspended and fixed to a tip portion of a support arm 1 of a steel tower by a plurality of bolts 3. A jumper wire 5 is supported on the lower end portion of the support insulator 2 via an electric wire clamp 4, and both ends of the jumper wire 5 are connected to a power transmission line (not shown) supported on the support arm 1 via a tension insulator device. Has been done.
A mounting bracket 6 is fixed to the tip of the support arm 1 and extends horizontally in a direction orthogonal to the line direction. A lightning protection insulator 7 is fixed to the lower part of the tip of the mounting bracket 6 by a plurality of bolts 8.

The lightning protection insulator 7 is a voltage-current characteristic whose main material is a pressure-resistant insulating cylinder (not shown) formed in a cylindrical shape from a tension-resistant material such as FRP, and zinc oxide (ZnO) housed in series therein. Are provided on the outer periphery of the pressure-resistant insulating tube, the non-linear current-limiting element 9, the cap-shaped electrode fittings 10 and 11 on the grounding side and the charging side that are fitted and fixed to both ends of the pressure-resistant insulating tube. It is composed of a molded rubber 12. Circular arc horns 13 and 14 are provided to face the mounting bracket 6 and the electrode fitting 11, respectively.
Damage to the molded rubber 12 at the time of surface flashover is reduced.

A discharge electrode 15 on the charging side is attached to an electric wire clamp 4 of the support insulator 2 via an attachment body 16. In addition, the charge side electrode fitting 11 at the tip of the lightning protection insulator 7 has a ground side discharge electrode
17 is attached via a mounting plate 18. The discharging portions of the discharge electrodes 15 and 17 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 15 and 17 will be described in detail. As shown in FIGS. 2 and 3 (a), the discharge electrode 15 on the charging side includes a pair of circular ring-shaped discharge parts 15a. The two connecting rods 15b are connected and fixed at a predetermined interval, and the base end of the upper discharge portion 15a is attached via the support portion 15c.
It is fixedly supported on 16. Similarly, the discharge electrode 17 on the ground side has a pair of circular ring-shaped discharge parts 17a.
It is configured such that the book is connected and fixed at a predetermined interval by a connecting rod 17b, and the base end of the upper discharge part 17a is fixed and supported by the mounting plate 18 via a support part 17c. The pair of discharge parts 15a and 17a are arranged to face each other with the air discharge gap G in the same plane. The opposing portions of the two discharge portions 15a and 17a are formed in an arc shape that is convex to each other. It is better to dispose several connecting rods 15b and 17b in the vicinity of positions where they are opposed to each other so as to further alleviate the electric field in this portion.

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

In this lightning protection horn insulator device, when a surge current caused by lightning strike is applied to the jumper wire 5, the current is discharged in the air discharge gap G between the discharge electrodes 15 and 17 and built in the lightning protection insulator 7. Current limiting element 9 and mounting bracket 6
After that, it flows to the support arm 1 of the steel tower and is discharged from the steel tower to the ground. Further, the subsequent flow generated thereafter is the discharge electrode 1
It is suppressed and cut off by the air discharge gap G between 5 and 17 and the current limiting element 9 in the lightning protection insulator 7.

In the lightning protection horn insulator device of this embodiment,
Since the discharge parts 15a and 17a of the discharge electrodes 15 and 17 on the charging side and the grounding side are respectively formed in a circular ring shape and face each other with a predetermined air discharge gap G in the same plane, As shown by the chain line in Fig. (A), each pair of discharge parts 15a, 17a exerts a bundle conductor effect, and the gap length of the air discharge gap G is set to be small so that lightning impulse is easily discharged. Even if it is configured, the resistance becomes high with respect to the opening / closing impulse and it becomes difficult to discharge. By the way, comparing the device of this embodiment with a conventional device having a rod-shaped discharge electrode, it is clear from FIG. 17 that the characteristics of the switching impulse with respect to the gap length of the air discharge gap G is about 30%. Improved.

As shown in FIG. 3 (b), each pair of discharge parts 15a,
If the 17a are not arranged to face each other in the same plane, but are arranged in a stepped manner, the electric field is concentrated between the one upper discharge portion 15a and the other lower discharge portion 17a that are in close proximity, It is not preferable because the open / close impulse characteristics cannot be improved.

In the lightning protection horn insulator device having a transmission voltage of 66 KV, the ring diameter D of the discharge parts 15a and 17a of the discharge electrodes 15 and 17 is 100 mm.
Then, the withstand voltage multiples of the switching impulse were tested with the discharge parts 15a and 17a having a sectional diameter d of 16 mm and 30 mm, and 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. 17, the discharge gap G is reduced by the low lightning impulse.
Since the discharge occurs at, it is possible to secure the insulation cooperation against the lightning impulse.

(Another Embodiment) Next, another embodiment of the present invention will be described with reference to FIGS.

First, in the second embodiment shown in FIGS. 4 and 5,
The discharge electrodes 15 and 17 on the charging side and the grounding side are respectively composed of one circular ring-shaped discharge portion 15a, 17a, and these discharge portions 15a, 17a are arranged facing each other with an air discharge gap G in the same plane. Has been done.

Therefore, in the second embodiment, unlike the above-described first embodiment, the bundle conductor effect in the discharge parts 15a and 17a cannot be expected, but the circular ring-shaped discharge parts 15a and 17a are arranged in the same plane. Even if the gap length of the air discharge gap G is set to be small and the discharge impulse is easily discharged by the opposed arrangement, the resistance becomes high against the opening / closing impulse and the discharge is difficult. The characteristics of the switching impulse with respect to the gap length of the air discharge gap G can be improved.

Next, in the third embodiment shown in FIG. 6, the discharge electrodes 15 and 17 on the charging side and the grounding side each have three circular ring-shaped discharge parts 15a and 17a by a plurality of connecting rods 15b and 17b. It is configured to be connected and fixed at a predetermined interval. The tip edges of the discharge parts 15a and 17a are arranged in an arc shape when viewed from the front, and the discharge parts 15a and 17a are arranged to face each other with an air discharge gap G in the same plane.

Therefore, in the third embodiment, a larger bundle conductor effect can be expected than in the case of the first embodiment, and the characteristics of the switching impulse with respect to the gap length of the air discharge gap G can be remarkably improved. .

Further, in the fourth embodiment shown in FIG. 7, the discharge electrodes 15 and 17 on the charging side and the grounding side are respectively provided with one support portion 15c from the central portion of the discharge portions 15a, 17a each having a planar shape and a substantially semi-arcuate shape. , 17c
It is configured to project. Further, in the fifth embodiment shown in FIGS. 8 and 9, the discharge electrodes 15 and 17 on the charging side and the grounding side respectively draw two flat discharge portions 15a and 17a having a substantially semi-arcuate shape. The support portions 15c and 17c are formed integrally with each other, and the supporting portions 15c and 17c project from the central portions thereof.

Therefore, also in the fourth and fifth embodiments, the gap length of the air discharge gap G is set to be small in the same manner as in the above-described second and first embodiments, so that the lightning impulse is discharged. Even if it is configured to be easy to perform, the resistance becomes high with respect to the opening / closing impulse and it becomes difficult to discharge, and the characteristics of the opening / closing impulse with respect to the gap length of the air discharge gap G can be improved.

In FIG. 9, the discharge parts 15a and 17a may be drawn on opposite sides.

Next, in the sixth embodiment shown in FIGS. 10 and 11,
The support plate 19 is fixed to the outer periphery of the base end of the discharge electrode 15 on the charging side composed of the pair of circular ring-shaped discharge portions 15a, and the mounting hole 20a and the arc-shaped adjustment elongated hole 20b are provided outside the mounting body 16. A mounting piece 20 having is provided so as to project. Then, with the bolt 21 inserted into the mounting hole 20a and the elongated hole 20b of the mounting piece 20 via the support plate 19, the discharge electrode 15 on the charging side is located outside the electric wire clamp 4 within the range of the elongated hole 20b. It is attached so that its rotation can be adjusted.

Further, a long hole 18a extending in the lateral direction is formed in a mounting plate 18 fixed to the outside of the base end of the discharge electrode 17 on the ground side composed of a pair of circular ring-shaped discharge parts 17a, and the lower end of the lightning protection insulator 7 is formed. A fixing plate 22 having a mounting hole 22a and an adjusting elongated hole 22b extending in the vertical direction is attached to the power-supply-side electrode fitting 11 of the section. Then, with the bolt 23 inserted into the mounting hole 22a and the long hole 22b of the fixed plate 22 through the long hole 18a of the mounting plate 18, the discharge electrode 17 on the ground side is below the electrode fitting 11, and the range of the long hole 18a. It is mounted so as to be movable and adjustable within the slot 22b.

Therefore, in this sixth embodiment,
As in the case of the embodiment, the characteristics of the switching impulse with respect to the gap length of the air discharge gap G can be improved,
Moreover, by rotationally adjusting the discharge electrodes 15 and 17 on the charging side and the ground side, the discharge parts 15a and 17a of both discharge electrodes 15 and 17 can be easily arranged to face each other in the same plane, and at the same time, grounding can be performed. By adjusting the discharge electrode 17 on the side,
It is possible to easily change the setting of the air discharge gap G between 15a and 17a.

Furthermore, the decrease in the air discharge gap G means that rainwater
Since electrical shortening due to icing etc. is likely to occur, water repellency treatment using a material such as Teflon or silicon (coating, tube covering, etc.) except for the discharge generation point will further improve the reliability of the characteristics. improves.

Next, a seventh embodiment embodying the invention according to claim 2 of the present invention will be described with reference to FIGS. 12 and 13.

As shown in FIG. 12, the suspension armature support 32 is supported by the support arm 1 via the upper suspension metal fitting 31, and the lower suspension metal fitting 33 and the electric wire clamp 4 are provided at the lower end portion of the suspension insulator series 32. The power transmission line L is supported. A mounting plate 34 is fixed to one side of the electric wire clamp 4, and the discharging electrode 15 on the charging side is attached to the mounting plate 34.
Are attached by bolts. This discharge electrode 15 is
As shown in Fig. 13, a semi-circular discharge part 15a and both discharge parts 1
A closed loop forming portion 15d that electrically and mechanically connects both ends of 5a to each other, a connecting portion 15b that connects the both closed loop forming portions 15d to each other, and further the connecting portion 15b to the mounting plate 34.
And a support rod 35 that supports the.

On the other hand, a lightning protection insulator 7 is attached to the supporting arm 1 by a mounting bracket 6, and a discharge electrode on the ground side is attached to a lower end portion thereof.
17 are supported. As shown in FIG. 13, the discharge electrode 17 includes a pair of semi-arc-shaped discharge parts 17a, a closed loop forming part 17d electrically and mechanically connecting both ends of the discharge parts 17a to each other, and It is composed of a connecting rod 17b connecting both closed loop forming portions 17d to each other, and a support rod 36 connecting the connecting rod 17b to the power-supply-side electrode fitting 11 of the lightning protection insulator 7.

In this embodiment, both ends of the discharge parts 15a, 17a of the discharge electrodes 15, 17 are mechanically connected by the closed loop forming parts 15d, 17d so as to form an electrically closed loop, so that a semi-arc discharge is formed. The electrodes can relax the electric field generated around the discharge parts 15a and 17a in the same manner as the annular discharge electrode, and can improve the insulation strength of the air discharge gap G.

If the closed loop forming portion 15d, 17d does not exist, the electric field generated around the discharge portion 15a, 17a, while wrapping around the inside of the discharge portion, becomes a semi-circular shape as a whole, therefore, the discharge portion 15a, Electric field concentration is likely to occur at the tip of 17a, but in the case of the seventh embodiment, closed loop forming portions 15d, 17
By providing d, electric field concentration is less likely to occur as in the case where an annular discharge electrode is used, and the discharge electrode can be reduced in size and weight because it has a semicircular shape as a whole. Since it is small, there is also an advantage that the air discharge gap G can be easily secured.

Next, an eighth embodiment embodying the present invention is shown in FIGS.
It will be described based on FIG.

In this embodiment, in the tension-type lightning arrester shown in FIG. 1, the mounting position of the lightning arrestor 7 is on the lower surface of the support arm 1, and the structure of the discharge electrode on the voltage application side and the ground side is 15th.
As shown in the figure, both ends of the semi-arc shaped discharge parts 15a, 17a are connected to each other by closed loop forming parts 15d, 17d, and the closed loop forming parts 15d, 17d are connected to each other by connecting rods 15b, 17b.
Support rods 35 and 36 for connecting the closed loop forming portions 15d and 17d to the mounting body 16 and the electrode fitting 11, respectively.

In the eighth embodiment as well, similar to the seventh embodiment described above, it is possible to alleviate the concentration of the electric field generated in the discharge parts 15a and 17a and improve the electric characteristics.

Note that, as shown in FIG. 16, the discharge portions 15a and 17a and the closed loop forming portions 15d and 17d of the discharge electrodes on the charging side and the grounding side can be formed by bending a strip-shaped plate material, respectively.

[Advantages of the Invention] As described above, according to the present invention, at least the discharge portions of the discharge electrode on the charging side and the discharge electrode on the ground side are formed in an arc shape so that the facing portions thereof are convex. ,
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.

[Brief description of drawings]

FIG. 1 is a front view showing a first embodiment of a lightning protection horn insulator device embodying the present invention, and FIG. 2 is an enlarged perspective view showing discharge electrodes on the charging side and the grounding side, and FIG. a) is an enlarged front view of both discharge electrodes, FIG. 3 (b) is a front view showing a different arrangement of discharge electrodes for comparison with this embodiment, and FIG. 4 is a second embodiment of the present invention. FIG. 5 is a front view of a lightning protection horn insulator device, FIG. 5 is an enlarged perspective view of its discharge electrode, FIG. 6 is a front view of a discharge electrode showing a third embodiment of the present invention, and FIG. 7 is this invention. FIG. 8 is a perspective view of a discharge electrode showing a fourth embodiment of the present invention, FIG. 8 is a perspective view of a discharge electrode showing a fifth embodiment of the present invention, and FIG. 9 is a longitudinal sectional view of the discharge electrode.
FIG. 11 is a partial front view of a lightning protection horn insulator device showing a sixth embodiment of the present invention, FIG. 11 is an exploded front view showing its discharge electrode removed, and FIGS. 12 and 13 are the seventh embodiment of the present invention. FIG. 12 is a front view showing a suspension type lightning arrester, FIG. 13 is an enlarged perspective view showing discharge electrodes on a charging side and a grounding side, and FIGS. 14 and 15 are eighth embodiments of the present invention. FIG. 14 is a front view of a tension-type device, etc., FIG. 15 is an enlarged perspective view showing discharge electrodes on the charging side and the ground side, FIG. 16 is a perspective view showing another example of discharge electrodes, FIG. 17 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, 2 ... Support insulator, 5 ... Jumper wire, 7 ... Lightning arrester, 15 ... Discharge electrode on the charging side, 15a, 17
a: Discharge part, 15d, 17d: closed loop forming part, 17: ground side discharge electrode, G: air discharge gap.

Claims (2)

[Claims] 1. A support insulator (2) for a support arm (1) of a steel tower.
Via the power transmission line, the lightning protection insulator (7) is supported at the tip of the support arm (1), and the discharge electrode (15) on the power supply side is connected to and supported by the power transmission line. (7)
A lightning protection horn insulator device having a ground side discharge electrode (17) provided at an end of a grounding side discharge electrode (15) and a ground side discharge electrode (1).
7) At least the discharge parts (15a, 17a) are formed in an arc shape so that the facing parts are convex, and the discharge parts (15a, 17a) are opposed to each other with a predetermined air discharge gap (G). A lightning protection horn insulator device. 2. The invention according to claim 1, wherein the discharge parts (15a, 17a) of the discharge electrode (15) on the charging side and the discharge electrode (17) on the ground side are formed in a semicircular shape, respectively. Both ends of the discharge part (15a, 17a) are connected by a substantially linear closed loop forming part (15d, 17d), and the discharge part and the closed loop forming part form an electrically closed loop. Characteristic lightning protection horn insulator device.