JPH0231939Y2 - - Google Patents

Description

[Detailed explanation of the idea]

Industrial Application Field The present invention relates to a lightning disconnection prevention device. Prior Art In power distribution lines, when overvoltage caused by lightning surge flashes over, grounding objects with non-uniform voltage-current characteristics are used to suppress and interrupt the accompanying current and prevent wire breakage and damage to the insulators due to follow-on arcs. A lightning disconnection prevention device is installed in which a ground-side horn is attached via a linear current-limiting element unit, and the horn is opposed to an insulated wire held by a high-voltage insulator with a discharge gap. However, in power distribution lines, insulated wires are mostly held by metal binding wires, and when flashover occurs due to lightning surges, the sheathing of the insulated wires is destroyed, so once flashover occurs, the binding wires are Furthermore, when installing the ground side horn, the horizontal and downward angles of the installed wires will vary depending on the topographical conditions of the line, so the discharge gap will not be constant and the discharge voltage characteristics will become unstable. Also, in order to avoid charging the bound wire, some wire-side horns for discharging are attached at a location away from the wire gripping point, but in this case, the grounding-side horn needs to be extended far away. There is,
There are many problems during installation and repair. Moreover, in the conventional lightning disconnection prevention device as described above, the ground side horn is arranged horizontally with a ring or a flat plate, etc. in consideration of the arc-inducing property in the event of a flashover, compared to the protruding wire side horn. In the case of a negative polarity lightning surge, the discharge starting voltage is significantly higher than in the case of positive polarity, and flashover may occur on the insulator surface before the discharge gap. As a result, adjustment of the two has become an important issue for the above-mentioned lightning disconnection prevention device. Purpose of the invention The present invention was made to eliminate the above-mentioned drawbacks, and its purpose is to easily and safely install and repair the wire-side horn and the ground-side horn, and to improve the installation condition of the wires. A lightning disconnection prevention device that can freely adjust the discharge gap according to the lightning surge polarity, exhibit stable discharge characteristics depending on the polarity of lightning surges, and improve safety by eliminating the exposure of live parts. It is about providing. Structure of the invention In order to achieve the above object, the present invention attaches a horn unit on the wire side to an insulated wire held by a high-voltage insulator with a bind wire, and connects a grounding object such as a arm arm through a current-limiting element unit. In a lightning disconnection prevention device in which a side horn is attached with a discharge gap between the side horn and the wire side horn unit, an insulating compound coated on the insulated wire and the binding wire, an insulating cover containing the insulating compound; A wire-side horn is attached to the insulating cover and penetrates through the sheath of the insulated wire to connect to the core wire, forming the wire-side horn unit, which is attached to the insulated wire from above the binding wire and fixed to the grounding object. and a vertical support arm in which a guide hole is formed in the vertical direction, and a movable mounting bracket attached to the vertical support arm via a tightening bolt that is slidably fitted into the guide hole. A movable part is configured to support the current limiting element unit on the vertical movable part, and further includes a support arm supported by the energized side electrode of the current limiting element unit, and a support arm formed in a plate shape and supporting the current limiting element unit. A horizontally movable part is constituted by a ground-side horn that is horizontally rotatably connected to the support arm via a bolt, and a plurality of protrusions are provided on the side of the ground-side horn opposite to the wire-side horn unit. We are hiring. Embodiment Below, an embodiment embodying the present invention is shown in Fig. 1~
Referring to FIG. 6, a high voltage insulator 2 is fastened by bolts 3 and nuts 4 to the upper surface of a cross arm 1 which is horizontally fixed to a utility pole (not shown). An insulated wire 5 is tied to the upper end of the high-voltage insulator 2 by a bind wire 6, and a wire-side horn unit 31, which will be described later, is mounted on the insulated wire. A band fitting 7 is fastened and fixed to the lower end of the high voltage insulator 2, and a vertical support arm 8 having a vertically elongated guide hole 8a is integrally formed downward on one side of the metal fitting 7. As shown in FIGS. 2 and 3, a movable mounting bracket 9 is fitted into the vertical support arm 8 into a guide hole 8a of the vertical support arm 8, and a coil spring 12 is interposed between the vertical support arm 8 and the movable mounting bracket 9. Tightening bolt 10 and nut 1 that can be loaded and fired
1, it is held at a desired height position so as to be slidable in the vertical direction, and can also be fixed. A washer 13 is interposed between the vertical support arm 8 and the nut 11, and these members form a vertical movable portion K1. A horizontal support arm 14 is integrally bent at the lower end of the movable mounting bracket 9, and a mounting ring 14a formed at the tip of the horizontal support arm 14 has irregular voltage-current characteristics as shown in FIG. A linear current-limiting element 15, electrodes 16, 17 on the voltage application side and the grounding side connected to the upper and lower surfaces of the current-limiting element 15, and these 3
A current limiting element unit 19 made of an elastic insulator 18 etc. integrally molded so as to cover the two members is erected and fixed. A nut 20 is screwed into the lower end male threaded portion 17a of the ground side electrode 17, and the mounting ring 14 of the horizontal support arm 14
An insulating bush 21 is interposed between the ground electrode 17 and the nut 20, and the nut 20
A terminal fitting 2a of a grounding wire 22, which is connected to a grounding object such as an arm arm 1, is interposed between the insulating bushing 21 and the mounting ring 14a, the bushing 21, and the terminal fitting 22a, together with the washer 21a, are connected to the nut 20. It is tightened and fixed. The grounding wire 22 can be connected in series with an operation indicator of the device for preventing lightning disconnection of the present invention due to lightning surges, a deterioration indicator of the current-limiting element 15, etc., if necessary. The ground side electrode 17 and the horizontal support arm 14 and below can be directly grounded without using the wire 22 and the insulating bush 21. A support arm 23, which is a rectangular plate made of a conductive plate, is attached to the upper end surface of the voltage-supplying electrode 16, and is attached to the bolt 2.
It is rotationally fastened by 5. Further, a ground horn 26 made of a conductor and formed by punching into a flat rectangular shape is fastened to the tip of the support arm 23 by a support fitting 27, a bolt 28, and a nut 29 so that its rotational position in the horizontal direction can be adjusted. These members form a horizontal movable section K2. A plurality of protrusions 30 are bent upward on the outer peripheral surface of the ground horn 26. These protrusions 30 are molded at the same time when the ground side horn 26 is press molded. Further, in this embodiment, the height h of the protrusion 30 from the top surface of the ground side horn 26 is set to 103, for example.
mm. On the other hand, the ground side horn 26 of the insulated wire 5
At the position corresponding to the wire side horn unit 31
is installed. This wire side horn unit 3
1 includes an insulating compound 32 applied to the outer surface of the insulated wire 5, a cylindrical insulating cover 33 fitted so as to cover the binding wire 6 via the compound 32, and a cylindrical insulating cover 33 formed integrally with the insulating cover 33. An insulating base 34 is screwed and fixed to the boss portion 33a, and an insulating base 34 is fixed to the insulating base 34, and when the base 34 is screwed, it penetrates the covering portion 5a of the insulated wire 5 and electrically contacts the core wire 5b. It is constituted by a rod-shaped electric wire side horn 35 made of a screw. The insulating cover 33 is formed with a thin wall portion 33b, which is opened centering on the thin wall portion 33b when the insulated wire 5 is fitted, as shown by the two-dot chain line in FIG. Furthermore, an ear portion 33c is formed on the insulating cover 33, and a locking pin 36 is fixed to one ear portion 33c, and the locking pin 36 is attached to a locking hole 33d formed in the other ear portion 33c. The insulating cover 33 is fixed to the insulated wire 5 by passing through the insulated wire 5. Furthermore, both ends of the insulating cover 33 are formed to have a small diameter as shown in FIG. 4, and a recess 33e through which the binding wire 6 passes is formed in a part thereof as shown in FIG. As shown in FIG. 4, in this embodiment, the discharge gap G between the wire side horn 35 and the ground side horn 26 is set to 60 mm (6KV distribution line), as an example. Next, the operation of the lightning disconnection prevention device constructed as described above will be explained. Now, in the installed state of the lightning disconnection prevention device shown in FIGS. 1 and 4, when a lightning pulse overvoltage caused by a lightning strike is applied to the insulated wire 5, the wire-side horn 35 electrically contacts the core wire 5b. Discharge end 35
a, flashes over through the discharge hole 34a of the insulating base 34, is captured by the ground side horn 26,
After that, it is grounded via the support arm 23, the voltage-side electrode 16, the current-limiting element 15, the grounding side electrode 17, the nut 20, the terminal fitting 22a, the grounding wire 22, the arm 1, a lead wire (not shown), etc., and is thus connected. Since the flow is suppressed and blocked, wire breaks due to follow-on arcs are prevented. By the way, when the lightning impulse overvoltage caused by a lightning strike is of positive polarity, experimental results show that the torsion voltage (expressed as FOV in the table) of both the conventional ground-side horn and the ground-side horn of the present invention shown in the following table is 60KV. On the other hand, when the lightning impulse overvoltage is of negative polarity, the conventional flashover voltage between horns is as high as 90KV, and therefore, in order to satisfy the arc-inducing property in negative polarity, the flashover voltage must be The discharge gap G must be shortened until the voltage is close to 70KV.

[Table] However, in the lightning disconnection prevention device of the present invention, since the protrusion 30 is provided on the ground side horn 26, even if the discharge gap G is maintained at 60 mm, the flashover voltage can be reduced in the case of positive polarity. By suppressing the voltage to 65KV, which is close to the circuit voltage (60KV), it is possible to satisfy the arc-inducing property in the case of negative polarity. In this way, in the present invention, even if the discharge gap is the same, both positive and negative polarity arc induction properties can be maintained, and flashover on the surface of the high voltage insulator 2 can be prevented even if overvoltage occurs due to a lightning strike. , insulation coordination can be maintained due to the discharge gap.The reason for this is that by providing the protrusion 30 on the ground side horn 26, in the case of negative polarity, the electric field is concentrated on the protrusion 30 and the potential gradient near the tip of the protrusion is increased. This is because it is possible to promote the sparkling between the horns. If the height h of the protrusion 30 becomes too large,
This is a problem because the discharge characteristics change in the case of positive polarity, and for this reason, the height h is set to 1 to 3
mm, to minimize the effect on positive polarity. Further, in the embodiment of the present invention, the wire-side horn 35 of the wire-side horn unit 31 is connected to the core wire 5b at the center of the winding pitch P of the bind wire 6, and the bind wire 6 and the wire-side horn 35 are connected to each other by the insulating compound 32. Since the insulation between the wire and the wire is strengthened, even if the wire-side horn unit 31 is installed near the high-voltage insulator 2, that is, at the binding point, the bind wire 6 will not be charged. It can be done easily and safely while the line is still in place. Furthermore, in the embodiment of the present invention, the ground side horn 26 is mounted so that its position can be adjusted in the vertical and horizontal directions by the vertically movable part K1 and the horizontally movable part K2, so that the horizontal angle or pull-down angle of the insulated wire 5 can be adjusted. The discharge gap G can be adjusted to a constant value according to the
Discharge voltage characteristics can be stabilized. especially,
Since the vertically movable part K1 is equipped with a movable mounting bracket 9 that is slidably attached under the spring of the coil spring 12, the current limiting element unit 19 can be easily positioned and can be left temporarily fixed during work. Since the current-limiting element unit 19 can be held in a predetermined position, work efficiency is particularly good in line work performed in close proximity to live electric lines such as power distribution lines. Note that the present invention is not limited to the above-mentioned embodiments, and for example, as shown in FIG. Horn 2 as shown
6 may be provided with a protrusion 30 made of a screw or rivet, or a pin may be implanted in the horn 26 to form the protrusion 30 as shown in FIG. It is also possible to change to Effects of the Invention As detailed above, the present invention particularly includes forming the ground side horn in a plate shape, and providing a plurality of protrusions on the side of the ground side horn opposite to the wire side horn.
Since it is possible to maintain almost the same arc-inducing properties against both positive and negative lightning impulse overvoltages in the same discharge gap, it is possible to maintain insulation coordination through the discharge gap, and to prevent flashover caused by lightning surges. It is possible to securely capture and prevent flashover on the insulator surface, and since the ground side horn is installed with a vertically movable part and a horizontally movable part so that its position can be adjusted, the discharge gap can be adjusted according to the installation state of the wire. can be adjusted freely and the discharge voltage characteristics can be stabilized.Furthermore, the wire-side horn unit contains an insulating compound to strengthen the insulation between the binding wire and the wire-side horn. Even if the ground side horn is installed near the binding point, charging of the binding wire can be avoided and the installation area of the pole can be reduced. Exposure of the live part is also avoided, making it possible to install and repair the horn unit even when the wire is live. It is effective and can be done easily and safely.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an embodiment of the lightning disconnection prevention device of the present invention, FIG. 2 is an enlarged sectional view taken along the line A-A in FIG. 1, and FIG. 3 is an enlarged exploded perspective view of the vicinity of the vertical movable part.
Fig. 4 is an enlarged front view of the main parts, Fig. 5 is an enlarged plan view of the ground side horn, Fig. 6 is a sectional view of the wire side horn unit, and Figs. 7 a to c show other examples of the ground side horn. FIG. DESCRIPTION OF SYMBOLS 1... Bracelet, 2... High-voltage insulator, 5... Insulated wire, 5a... Sheathing part, 5b... Core wire, 6... Bind wire, 7... Band fitting, 8... Vertical support arm, 8a... ...Guide hole, 9...Movable mounting bracket, 1
0... Tightening bolt, 11... Nut, 14... Horizontal support arm, 19... Current limiting element unit, 22
...Grounding wire, 23...Support arm, 26...Ground side horn, 28...Bolt, 30...Protrusion, 31
... wire side horn unit, 32 ... insulation compound, 33 ... insulation cover, 35 ... wire side horn, K1 ... vertical movable part, K2 ... horizontal movable part, G ... discharge gap.

Claims (1)

[Claims for Utility Model Registration] 1. A wire-side horn unit 31 is attached to an insulated wire 5 held by a high-voltage insulator 2 with a bind wire 6, while a current-limiting element unit 19 is connected to a grounded object such as an arm arm 1. In the lightning disconnection prevention device in which the ground side horn 26 is attached with a discharge gap G between the wire side horn unit 31, the insulating compound 32 coated on the insulated wire 5 and the binding wire 6, and the insulation An insulating cover 33 containing a compound 32, and a wire-side horn 35 attached to the insulating cover 33 and penetrating the covering portion 5a of the insulated wire 5 and contacting the core wire 5b.
The wire-side horn unit 31 is configured by the above, and is attached to the insulated wire 5 from above the bind wire 6, and is fixed to the ground object and has a vertical support arm 8 formed with a guide hole 8a in the vertical direction. and,
A vertical movable part K1 is constituted by a movable mounting bracket 9 attached to the vertical support arm 8 under the force of a coil spring 12 by a tightening bolt 10 slidably fitted into the guide hole 8a. The current-limiting element unit 19 is supported on the vertical movable part K1, and the supporting arm 23 is formed in a plate shape and is supported on the energized side electrode 16 of the current-limiting element unit 19. The ground side horn 26 is horizontally rotatably connected to the support arm 23 via a bolt 28 to form a horizontally movable part K2. A lightning disconnection prevention device characterized in that a projection 30 is provided. 2. The lightning disconnection prevention device according to claim 1, wherein the ground horn 26 is formed by punching a metal plate into a predetermined shape and bending the outer side of the metal plate at a plurality of places to form protrusions 30. 3. The lightning disconnection prevention device according to claim 1, wherein the ground side horn 26 is formed by punching a metal plate into a predetermined shape and having projections 30 made of screws or rivets fixed on the plane thereof.