JP2555100B2 - Lightning protection horn insulator device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention rapidly discharges a high voltage caused by a lightning strike applied to a transmission line and shuts off a follow-up current generated thereafter. The present invention relates to a lightning protection horn insulator device for an overhead power transmission line for preventing a permanent ground fault.

(Prior Art) Conventionally, as a device for mounting a lightning protection insulator on a power transmission line with a predetermined air discharge gap, the applicant of the present application has disclosed in Japanese Patent Laid-Open No. 62-8.
The one disclosed in Japanese Patent No. 0922 is proposed. This device will be described with reference to FIG. 3. A suspension metal fitting 6 is connected to a support arm 1 of a steel tower, and an upper suspension metal fitting J1 is rotatably connected to the suspension metal fitting 6 by suspension. The hanging insulator 2 is rotatably connected to the lower metal fitting J1 and hangs down. The power transmission line 3 is supported on the lower portion of the hanging insulator 2 via a lower hanging metal fitting J2.

On the other hand, the upper suspension bracket J1 has a mounting arm 19 and a mounting plate 2
The lightning protection insulator 4 is suspended and fixed in a state of being displaced by a predetermined distance in the line direction with respect to the suspension light insulator 2 via 2, and the lower suspension metal fitting J2 is extended to the lightning protection insulator 4 side on the side of the voltage applied. Arc horn 27 'is provided, the arc horn 25 attached to the lower part of the lightning protection insulator 4 and the arc horn 27' are opposed to each other with a predetermined air discharge gap G, and the tip 27 of the arc horn 27 'is provided.
The a'is positioned outside the hanging insulator 2 with respect to the vertical line H passing through the arc horn 25 and is raised from the horizontal plane. Even if the suspension insulator 2 swings in the line direction, the air discharge gap G is made substantially constant.

(Problems to be Solved by the Invention) However, in the conventional device, the distance between the arc horns 25 and 27 cannot be set to be equal to or less than the air discharge gap G,
This value is set to withstand the commercial frequency voltage and the switching surge voltage, and is set uniformly by the line voltage. Therefore, the height of the lightning protection insulator and the air discharge gap G is longer than that of the existing insulator series. It was necessary to raise the mounting plate 22 with respect to the mounting arm 19 to displace the entire lightning protection insulator 4 upward. In this way, when the lightning protection insulator 4 is mounted by being displaced upward, the air clearance C between the transmission line 3 located above and the upper end electrode fitting of the lightning protection insulator 4 decreases, so this displacement amount is left over. It could not be increased, and there was a problem in application in the existing steel tower. Further, even in a new steel tower, it is necessary to upsize the steel tower, which is a cost problem.

In view of the above circumstances, the present invention shortens the vertical lengths of the arc horn on the charging side and the arc horn on the grounding side to make the mounting position of the lightning protection insulator as close as possible to the lower side, and It is an object of the present invention to provide a lightning protection horn insulator device that can be easily mounted on a steel tower.

Configuration of the Invention (Means for Solving the Problems) In order to solve the above problems, the present invention rotatably connects a suspension insulator to a support arm of a tower through an upper suspension metal fitting, A lower suspension metal fitting for supporting a power transmission line is connected to the lower end of the suspension insulator, and a lightning protection insulator is suspended and supported by the support arm or the upper suspension metal fitting through an attachment arm. The lower metal fitting is provided with an arc horn on the power-supply side that forms a cone extending to the side of the lightning protection insulator, and the arc horn is covered with an insulating sleeve leaving the tip end thereof, and the insulating sleeve and the The configuration is such that the shortest distance from the grounding side arc horn attached to the lightning arrestor is set below the air discharge gap between the tip of the charging side arc horn and the grounding side arc horn.

(Operation) The present invention determines the shortest distance between the insulating sleeve coated on the arc horn on the side of charging and the arc horn on the side of ground attached to the lightning protection insulator, Since it was set below the air discharge gap with the arc horn, the hanging point of the lightning arrestor can be set to be equal to or lower than the height of the support arm or the upper hanging metal fitting, and it can be installed on the existing steel tower. It will be easy.

In addition, since most of the arc horn on the power supply side is covered with an insulating sleeve, even if a bird stops on the insulating sleeve and comes into contact with the arc horn on the ground side, the insulating property is retained by the sleeve. Accidents are prevented before they happen.

(Embodiment) An embodiment embodying the present invention will be described in detail below with reference to FIGS.

This embodiment is a lightning protection horn insulator device,
The electric wire 3 is suspended from the lower surface of the tip of the support arm 1 of the tower.
A suspension insulator 2 composed of a plurality of suspension insulators 2A, a lightning arrestor 4 attached to the upper side of the suspension insulator 2, and the lightning insulator 4 in a vertical state in balance with the weight of the lightning insulator 4 (gravity Direction) and a weight 5 for preventing abnormal vibration.

A suspension metal fitting 6 is fixed to the support arm 1 with bolts, and a U-clevis 7 is rotatably connected to the metal fitting 6. An upper horn mounting bracket 8 is connected to the U clevis 7 by a shaft 9 so as to be rotatable in the track direction (left-right direction in FIG. 1), and below the bracket 8 a shaft 10 is relatively rotatable in the track direction. Suspension insulator 2 via a right-angled clevis link 11 and a ball clevis 13 connected to the right-angled clevis link 11 by a shaft 12 so as to be relatively rotatable in the direction orthogonal to the line.
Are connected and suspended. In this embodiment, the hanging metal fitting 6, the U clevis 7, the upper horn mounting metal fitting 8, the right angle clevis 11, the ball clevis 13 and the like constitute an upper hanging metal fitting J1.

A lower horn mounting bracket 15 is connected to a lower portion of the suspension insulator 2 via a socket clevis 14 so as to be relatively rotatable in the line direction by a shaft 16, and a suspending clamp 17 for supporting the electric wire 3 is provided below the bracket 15. Are connected by a shaft 18 so as to be relatively rotatable in the track direction. In this embodiment, the socket clevis 14, the lower horn mounting bracket 15, the suspension clamp 17 and the like constitute a lower hanging bracket J2.

A mounting arm 19 extending in the track direction by a bolt 21 on the right side of the upper horn mounting bracket 8, and a track arm on the left side in the track direction.
Moreover, the mounting arms 20 extending diagonally downward are fixed in a cantilever manner.

On the lower surface of the mounting plate 22 fixed to the tip of the mounting arm 19,
The lightning protection insulator 4 is vertically fixed by bolts 23. The weight 5 is fixed to the tip of the mounting arm 20 by a bolt 24. Further, in the stationary state, the lightning protection insulator 4 and the weight 5 are set to be balanced about the shaft 9.

On the lower electrode 4a of the lightning protection insulator 4, a grounding side arc horn 25 (see FIG. 3) curved in an arc shape centered on the shaft 12 is attached extending in the line orthogonal direction. .
Also, a pair of arcing rings 26, 26 are provided on the upper and lower sides of the lightning protection insulator 4 in a cantilevered manner by the mounting plate 22 and the lower electrode 4a, respectively, and a pair of arcing rings 26, 26 are provided so as to surround the lightning protection insulator 4. When the lightning protection insulator 4 causes an abnormal discharge, the arc jet is swiftly transferred from the lightning protection insulator 4.

On the other hand, a linear arc horn 27 on the charging side in the line direction is attached to the lower horn mounting member 15 by a bolt 28, and faces the arc horn 25 with a predetermined air discharge gap G. The arc horn 27 is covered with an insulating sleeve 29 made of rubber or resin by being inserted, adhered or integrally molded, and the arc horn tip 27a faces the arc horn 25 with the discharge gap G. The shortest distance R between the insulating sleeve 29 and the arc horn 25 is set to the discharge gap G or less.

The tip portion 27a of the arc horn 27 is the arc horn 2
The discharge gap G is extended to the outside of a perpendicular line H (a line in the direction of gravity) passing through 5, and the discharge gap G is held substantially constant when the suspension insulator 2 swings in the line direction. In addition,
The discharge gap G is located at an intermediate position between the distance at which no discharge occurs between the arc horns 25 and 27 due to the commercial frequency voltage and the switching surge voltage and the distance at which the insulation strength of the discharge gap G does not exceed the insulation strength of the suspension insulator 2. It is set with a margin.

A pair of arc horns 30 extending downwardly on both sides of the base end of the mounting arm 19 for preventing damage at the time of a surface flash of the suspension insulator 2 are integrally formed with the mounting arm 19 and the bolts. It is fixed by 21, and the lower horn mounting bracket 15
On the other hand, it is fixed by a bolt 32 and faces an arc horn 31 extending in the line direction with a predetermined air discharge gap.

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

Now, when a lightning surge current enters the power transmission line 3, this surge current flows to the arc horn 27 ′ through the lower hanging metal fitting J2, and then flashes through the air discharge gap G to cause the lightning arrester 4 from the lower electrode 4a. It flows to the internal current limiting element (not shown), and the mounting plate 2
2. It flows to the support arm 1 through the mounting arm 19 and the upper hanging metal fitting J1 and is discharged. The subsequent current generated by the commercial frequency current is suppressed and cut off by the current limiting element and the air discharge gap G.

Now, in the embodiment of the present invention, the tip portion 27 of the arc horn 27 is
Since the insulating sleeve 29 is covered while leaving a, and the shortest distance R is set to the discharge gap G or less, the hanging point of the lightning arrester 4 can be set to be equal to or less than the height of the mounting arm 19. This makes it easy to install on an existing steel tower.

Moreover, since most of the arc horn 27 is covered with the insulating sleeve 29, even if a bird stops on the insulating sleeve 29 and comes into contact with the arc horn 25 on the ground side, the insulating property is retained by the sleeve 29. Ground faults are prevented before they happen.

 Further, the present invention may be implemented as follows.

Although the lightning protection insulator 4 is attached to the upper hanging metal fitting J1 in the above embodiment, the lightning protection insulator 4 should be supported to the support arm 1 via a mounting arm (not shown).

EFFECTS OF THE INVENTION As described in detail above, according to the present invention, the vertical distance between the arc horn on the charging side and the arc horn on the grounding side can be greatly shortened, whereby mounting of the lightning protection insulator is possible. It is possible to bring the height position closer to the arc horn on the side of voltage application, without changing the iron tower introduction to the existing steel tower,
It has an excellent effect that it can be easily installed and can prevent a ground fault accident due to a bird.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment embodying the present invention,
FIG. 2 is a right side view showing a state where the suspension insulator swings,
The figure is a front view showing a conventional example. 1 ... Support arm, 2 ... Hanging insulator, 3 ... Electric wire, 4 ...
… Lightning arrester, 6… Hanging fitting, 7… U clevis as hanging fitting, 8 (15) …… Upper (lower) horn mounting bracket, 19,20… Mounting arm, 25, 27… Arc Horn, 27
a ... Tip, 29 ... Insulation sleeve, R ... Shortest distance between insulation sleeve 29 and arc horn 25, H ... Vertical line, G ...
… Air discharge gap, J1 (J2) …… Upper (lower) hanging bracket.

Claims (1)

(57) [Claims] 1. A suspension insulator (2) is rotatably connected to a support arm (1) of a steel tower via an upper suspension metal fitting (J1), and the suspension insulator (2) is connected to a lower end portion of the suspension insulator (2). Is connected to a lower hanging metal fitting (J2) for supporting the power transmission line (3), and is connected to the support arm (1) or the upper hanging metal fitting (J1) via a mounting arm (19). 4) is hung and supported, and the lower hanging metal fitting (J2) is provided with an arc horn (27) on the side of power distribution extending to the side of the lightning arrestor (4).
7) is covered with an insulating sleeve (29), leaving the tip portion (27a), and the insulating sleeve (29) and the grounding side arc horn (25) attached to the lightning protection insulator (4). The shortest distance (R) is set to be equal to or less than the air discharge gap (G) between the tip portion (27a) and the arc horn (25) on the grounding side, the lightning protection horn insulator device.