JPH0740449B2 - Lightning arrester and lightning arrester including the same - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a suspension insulator type lightning arrester having both the function of a suspension insulator and the function of a lightning arrester, and a lightning arrester including the same.

(Prior Art) Conventionally, it has been considered to introduce a lightning arrester into a transmission line in order to absorb lightning and switching surges and prevent a ground fault in the transmission line. However, it is not preferable to attach a lightning arrester having only a lightning protection function to the transmission line because the transmission line tower structure and the insulator device are complicated. Therefore, the insulation of conventional insulators
Various types of lightning arresters have been proposed that have both a wire support function and a lightning arrester function (for example, see JP-A-55-32308). This lightning protection insulator has a lightning protection element built into the head of the insulator body, and the cap fitting, the pin fitting and the lightning protection element are electrically connected.

(Problems to be solved by the invention) However, since this lightning protection insulator has a lightning protection element built in the head, it has a lightning protection function and a load bearing function as a suspension insulator concentratedly near the central axis, that is, in the head. It is necessary to significantly increase the insulator connection length and make it difficult to coordinate the lightning protection function and mechanical strength.In addition, if the lightning protection element is destroyed by a large-scale lightning stroke, the degree to which the insulator is damaged is required. However, there is a problem in that it requires a large improvement in terms of mechanical reliability.

In order to solve the above-mentioned problems, the applicant of the present application has already developed a lightning protection insulator in which a lightning protection element is embedded in a cap portion of a suspension insulator and an insulating cylindrical portion provided so as to vertically penetrate the cap portion. (See Japanese Utility Model Application No. 59-275110) However, in this lightning protection insulator, since the lightning protection element is provided so as to penetrate through the cap portion of the suspension insulator, in the case where there is an electric shock exceeding the expectation, There has been a problem that the lightning protection element is damaged and becomes conductive, and the large current continues to flow through the lightning protection element without being interrupted, resulting in damage to the insulator.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a lightning protection insulator and a lightning protection device including the lightning protection insulator which solves the above problems.

Configuration of the Invention (Means for Solving the Problems) The lightning protection insulator of the first invention of the present application is such that the cap metal fitting is capped and fixed to the head of the insulator main body having the cap portion and the head portion, and the inside of the head portion. In a lightning arrester in which a pin metal fitting is fitted and fixed to the cap portion, a lightning arresting element extending in the vertical direction is provided, and upper and lower electrodes thereof are respectively connected to the cap metal fitting and the pin metal fitting, at least one outer periphery of the cap metal fitting is provided. It is said that the discharge protrusion is projected laterally, and the discharge protrusion and the upper electrode of the lightning arrester are connected via a connection lead that is sufficiently resistant to lightning surge and melts down when a large current continues. The composition is adopted.

The lightning arrester of the second invention of the present application connects a plurality of lightning protection insulators configured in the same manner as the first invention to each other so that the discharge projections on the outer periphery of the lightning protection insulators are vertically aligned. The tip of the lower arcing horn is arranged to face the outer side of the discharge protrusion of the uppermost lightning arrestor, and the tip of the lower arcing horn is placed to face the outer side of the discharge protrusion of the lowermost lightning insulator.

(Operation) According to the lightning protection insulator of the first invention of the present application, when the lightning protection element becomes conductive and a follow-up flow of a large current flows, the connection lead is melted and the arc generated at the melted portion causes the discharge protrusion. It collides with the lower surface, is deflected to its tip, and is discharged outward from the tip. For this reason, it is possible to minimize damage to the cap portion of the insulator body of another lightning protection insulator located above.

In addition, in the lightning arrester of the second invention of the present application, when the above-mentioned follow flow flows, the arc emitted outward from the discharge projection of the uppermost lightning insulator moves to the upper arcing horn, Since the arc emitted from the discharge protrusion of the lightning arrestor to the outside moves to the lower arcing horn, the arc flowing through the current limiting element is connected between the upper and lower arcing horns to prevent damage to each lightning insulator more reliably. You can

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

FIG. 3 shows the entire lightning arrester, in which a large number of suspension insulator type lightning insulators 3 are suspended in series via an arm 1 provided on a steel tower (not shown) via a support metal fitting 2. The power transmission line L is supported at the lowermost end of the transmission line via a suspension fitting 4.

As shown in FIG. 1, an insulator main body 5 constituting the lightning protection insulator 3.
Is a cap portion 5a, a plurality of pleats 5b integrally formed in an annular shape and concentrically on the inner surface of the cap portion 5a, and the cap portion 5a.
It is molded by a cylindrical head 5c with a lid integrally formed on the upper center of 5a. Further, a cap metal fitting 7 is capped and fixed to the outer periphery of the head 5c by cement 6, and an engaging recess 7a is formed in the metal fitting 7, and the pin metal fitting 8 of the lightning protection insulator 3 directly above.
Are engaged with each other. The upper portion of the pin metal fitting 8 is fixed inside the head portion 5c with cement 6, and the lower end thereof is engaged with the engaging recess 7a of the cap metal fitting 7 of the lightning protection insulator 3 directly below. In this way, a plurality of lightning protection insulators 3 are connected and suspended in series.

As shown in FIGS. 1 and 2, the cap portion 5a on the inner side of the fold portion 5b of the insulator body 5 has a plurality of (three in this embodiment) element storage holes 9 vertically penetrating the cap portion 5a. Are formed at equal intervals in the circumferential direction after the insulator body 5 is formed, and its planar shape is a flat arc shape centered on the axis 0 of the pin fitting 8. A flat arc-shaped lightning protection element is provided in each element storage hole 9.
10 is adhered and fixed by an airtight adhesive 11 such as glass, resin or rubber. Each lightning protection insulator 10 is mainly made of zinc oxide (ZnO), which has a non-linear voltage-current characteristic with excellent follow-current blocking characteristics, and upper and lower ends of the upper electrode 13 made of the same metal.
And a lower electrode 14 are provided. The upper electrode
The outer peripheral portions of 13 and the lower electrode 14 are sealed by the solder 12.

A plurality (three in this embodiment) of discharge projections 15 are integrally formed laterally on the outer periphery of the cap metal fitting 7 so as to be located in the vicinity of the upper portions of the lightning protection elements 10 corresponding to the lightning protection elements 10. Has been done. A connection lead 16 that can be melt-cut against the follow current is fixed to the upper electrode 13 of each lightning protection element 10 by a conductive coupling material or the like, and the upper end thereof is connected and fixed to the lower surface of each discharge protrusion 15. A lead wire 17 is fixed to the lower electrode 14 of each lightning protection element 10 by a conductive coupling material or the like, and its inner end is connected and fixed to the pin fitting 8. Then, when the lightning striker 10 goes into a conducting state due to a higher-than-expected lightning strike and a large current continues to flow, the connecting lead 16 is blown out near the point P in FIG. 1 and the arc generated at the blown portion is discharged. It collides with the lower surface of the projection 15 and is deflected to the tip portion thereof, and is discharged outward from the tip portion.

Further, in the lightning arrester shown in FIG. 3, the plurality of lightning protection insulators 3 are connected to each other in a state in which the discharge projections 15 on the outer periphery of the lightning protection insulators 3 are vertically aligned and are emitted from the discharge projections 15 of each lightning protection insulator 3. The arc is connected between the corresponding upper and lower discharge protrusions 15. Further, the upper arcing horn 18 attached to the support fitting 2 is extended toward the lower outer side so that the tip end thereof is arranged outside the discharge projection 15 of the uppermost lightning protection insulator 3. There is. The tip of the lower arcing horn 19 attached to the hanging fitting 4 extends toward the outside of the discharge protrusion 15 of the lightning protection insulator 3 at the bottom. When the connecting lead 16 is melted, the arc emitted outward from the discharge protrusion 15 of the uppermost lightning protection insulator 3 moves to the upper arcing horn 18, and the arc outward from the discharge protrusion 15 of the lowermost lightning protection insulator 3. The arc emitted to the lower arcing horn 19 is transferred to the arcing horns 18 and 19 both above and below.

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

Now, in the lightning arrester shown in FIG. 3, when an excessive voltage of a lightning surge is applied to the power transmission line L, the current at this time flows from the hanging metal fitting 4 to the pin metal fitting 8 of the lowermost lightning protection insulator 3 → the lead wire. It is transmitted to the cap fitting 7 through 17 → lower electrode 14 → lightning protection element 10 → upper electrode 13 → connection lead 16. After that, the light is transmitted from the cap metal fitting 7 to the pin metal fitting 8 of the lightning protection insulator 3 immediately above, and thereafter sequentially transmitted to the plurality of lightning protection insulators 3 connected in series, and from the cap metal fitting 7 of the uppermost lightning protection insulator 3 to the support metal fitting. 2 and the arm 1 to be discharged to the ground.

At this time, the lightning protection element 10 built in the insulator body 5 quickly reduces its resistance value due to its characteristics and discharges the current due to the lightning surge. Further, with respect to the follow current continuing to the lightning surge, the lightning arrester element 10 immediately restores the resistance value and restores the insulation, so that the follow current discharge is suppressed and interrupted and the electric line is normally restored.

On the other hand, in this lightning protection device, the lightning protection element 10 of the lightning protection insulator 3
If the following flow flows through the lightning protection insulator 3 due to an unexpected lightning strike, the connecting lead 16 is blown off near the point P in FIG. 1 and the flow of the following flow is interrupted. The arc generated at the fusing part collides with the lower surface of the discharge projection 15 and is deflected to the tip portion thereof, and is emitted outward from the tip portion. Then, as shown in FIG. 3, the arcs emitted from the discharge protrusions 15 are connected between the discharge protrusions 15 located at the upper and lower positions, and a discharge is generated between the discharge protrusions 15. Therefore, the follow-up current does not continue to flow through the lightning protection element 10, and the arc is not emitted toward the cap portion 5a of the insulator body 5 of the other lightning protection insulator 3 located above, and the cap portion of the insulator body 5 does not exist. Damage to 5a is suppressed to a minimum.

Further, in this lightning arrester, after the arc is connected between the upper and lower discharge protrusions 15 as described above, it is emitted outward from the discharge protrusions 15 of the uppermost lightning protection insulator 3, as shown in FIG. As the arc moves to the upper arcing horn 18, the arc emitted outward from the discharge projection 15 to the lightning protection insulator 3 at the lowermost moves to the lower arcing horn 19, and the arcs are connected between the upper and lower arcing horns 18, 19. . Therefore, even if the discharge state continues, the insulator main body 5 of each lightning protection insulator 3 is not exposed to the arc, and the damage of the insulator main body 5 can be suppressed more reliably.

The present invention is not limited to the configuration of the above embodiment, but can be embodied as follows.

(1) As shown by a chain line in FIG. 2, a mounting band 21 made of a conductive material is orbitally fixed to the outer periphery of the cap metal fitting 7, and an outer peripheral discharge protrusion 15 of the mounting band 21 is projected.

(2) As shown by the chain line in FIG. 2, the discharge projection 15 is integrally formed on the outer periphery of the cap metal fitting 7 at a position that does not correspond to each lightning protection element 10, or is fixedly mounted via the mounting band 21.

(3) Attach the discharge projection 15 at the bottom to the pin fitting 8 as shown by the chain line in FIG.

Effects of the Invention As described in detail above, the first invention of the present application is such that, when the lightning arrester is in a conductive state and a large current continues to flow, the connection lead is melted and the arc generated at the melted portion is discharged. It has an excellent effect that it is discharged outward along the protrusion and damage to the cap portion of the insulator body can be suppressed to a minimum.

The second invention of the present application is such that, when the follow current flows, the arc emitted outward from the discharge protrusion of the uppermost lightning arrestor moves to the upper arcing horn, and from the discharge protrusion of the lowermost lightning insulator. The arc emitted to the outside moves to the lower arcing horn and the arcs are connected between the upper and lower arcing horns, so that it is possible to more reliably prevent damage to each lightning protection insulator.

[Brief description of drawings]

FIG. 1 is a semi-longitudinal sectional view of a lightning arrester showing an embodiment of the present invention, FIG. 2 is a sectional view taken along line AA of FIG. 1, and FIG. 3 shows a lightning arrester equipped with a plurality of lightning arresters. It is a schematic front view shown. 3 ... Lightning arrester, 5 ... Insulator body, 5a ... Kasabe, 6c ...
Head, 7 ... Cap metal fitting, 8 ... Pin metal fitting, 10 ... Lightning arrester element, 13 ... Upper electrode, 14 ... Lower electrode, 15 ... Discharge protrusion, 16 ... Connection lead.

Claims (5)

[Claims] 1. A cap metal fitting (7) is capped and fixed to a head portion (5c) of an insulator body (5) having a cap portion (5a) and a head portion (5c), and at the inner side of the head portion (5c). The pin metal fitting (8) is fitted and fixed, and the cap portion (5a) is provided with a lightning arresting element (10) extending in the vertical direction, and the upper and lower electrodes (13, 14) are connected to the cap metal fitting (7) and the pin metal fitting (8). ), Each of the caps (7) is provided with at least one discharge protrusion (15) projecting laterally on the outer circumference of the cap protrusion (15).
And the upper electrode (13) of the lightning protection element (10) are connected to each other through a connecting lead (16) that is sufficiently resistant to lightning surges and melts down when a large current continues to flow. . 2. A plurality of lightning protection elements (10) for the discharge protrusions (15).
The lightning protection insulator according to claim 1, wherein the lightning protection insulator is provided so as to respectively correspond to the positions. 3. The lightning protection insulator according to claim 1 or 2, wherein the discharge projection (15) is integrally formed on the outer periphery of the cap fitting (7). 4. The lightning protection insulator according to claim 1 or 2, wherein the discharge projection (15) is attached to the outer periphery of the cap fitting (7) via a mounting band (21). 5. A cap metal fitting (7) is capped and fixed to the head portion (5c) of an insulator body (5) having a cap portion (5a) and a head portion (5c), and is attached to the inside of the head portion (5c). The pin fitting (8) is fitted and fixed, and the cap portion (5a) is provided with a lightning protection element (10) extending in the vertical direction, and the lower electrode (14) thereof is connected to the pin fitting (8), and the cap fitting is attached. At least one discharge protrusion (15) and the upper electrode (13) of the lightning arrester (10) are connected to the outer periphery of (7), and the connection lead is sufficiently blown to withstand a lightning surge and blows when a large current continues. The lightning protection insulator (3) is configured by connecting via the (16), and the plurality of lightning protection insulators (3) are connected to each other so that the discharge protrusions (15) on their outer circumferences correspond to the upper and lower positions, and the upper arcing is performed. The tip of the horn (18) is arranged to face the outside of the discharge protrusion (15) of the uppermost lightning protection insulator (3) and Lightning arrester being characterized in that disposed opposite to the outer side of the discharge projections over King horn (19) distal the bottom of lightning protection insulator (3) (15).