JP2000021609A - Lightning arrester - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce parts number by forming out of an internal element of a lightning discharger integrated with a terminal metal electrode electrically connected to both ends of a lamination with non-linear resistors electrically connected each other, an insulating coating with an opening on its peripheral face and a polymer insulator molded on the peripheral face. SOLUTION: A lamination 21 is formed by laminating and electrically connecting a plurality of non-linear resistors 20 having zinc oxide as principal component. A terminal metal electrode 22 is electrically connected to both ends of the lamination 21 and an internal element 23 of a lightning discharger is formed by being integrated with the terminal metal electrode 22. A gap to the lightning arrester is securely hermetically sealed by covering its peripheral face with an insulating sheet 25 with an opening 24 molding a polymer insulator 26 on the peripheral face. An insulating sheet 25 is wound which has an opening in the circumferential direction of the internal element 23 of the lightning arrester and gas can blow out of the opening 24 in the radial direction even though the internal pressure is increased according to arc generation by penetration breakdown of the non-linear resistor 20 under overload rarely in lightning dischargers.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insulator type lightning arrester used in power plants and substations, and more particularly to a lightning arrester which minimizes damage at the time of a ground fault due to excessive responsibility. This is a technology for a lightning arrester that can improve the manufacturability and reduce the size.

[0002]

2. Description of the Related Art In aerial insulated substations and the like, insulator-type lightning arresters are mainly used to ensure insulation coordination of power plants.

Conventionally, a porcelain insulator is generally used as an insulating jacket for an insulator type lightning arrester. In recent years, a polymer insulator excellent in mechanical performance has been developed.

FIG. 9 is a sectional view showing a conventional lightning arrester using a polymer insulator.

As shown in FIG. 9, the lightning arrester 1 is
The lightning arrester internal element 2 is provided therein, and the polymer insulator 3 is provided on the outer peripheral surface of the lightning arrester internal element 2. In order to fix the lightning arrester inner element 2 in the polymer insulator 3, a lid 4 is provided on the upper part of the lightning arrester inner element 2 and the polymer insulator 3, and in order to apply axial force, the lid 4 and the lightning arrester inner element 2 Are connected via a spring 5.

In the lightning arrester 1, a laminated body 7 is formed by laminating non-linear resistors 6 mainly composed of zinc oxide, and terminal electrodes 8 are arranged at upper and lower ends of the laminated body 7. . Then, the laminate 7 and the terminal electrode 8 are integrated to form the lightning arrester internal element 2.

In order to prevent the arrester internal element 2 from shifting in the radial direction, a plurality of insulating rods 9 are uniformly arranged on the outer peripheral surface of the arrester internal element 2, and the upper and lower sides of the insulating rod 9 are fixed by caulking with insulating nuts 10. You. The lightning arrester internal element 2 is fixed to the center of the polymer insulator 3 by a lid 4 and a spring 5, and an insulating cylinder 11 is installed on the inner peripheral surface of the polymer insulator 3.

A lid 4 provided above the lightning arrester inner element 2 and the polymer insulator 3 is fixed by caulking with a nut 12. The lid 4 has a discharging mechanism for discharging pressure and gas to the outside of the lightning arrester 1. Pressure release port 13 is provided. The pressure relief port 13 prevents the lightning arrester 1 from exploding due to an increase in internal pressure due to the arc when a ground fault current exceeding the duty flows into the lightning arrester 1.

FIG. 10 is a sectional view showing a conventional lightning arrester using a polymer insulator. This lightning arrester has almost the same configuration as the lightning arrester shown in FIG.
The same reference numerals as in FIG. 9 denote the same parts as in FIG. 9, and a description thereof will be omitted.

In the lightning arrester 1 shown in FIG. 10, a plurality of weak points 14 are provided in the insulating cylinder 11 as a mechanism for releasing gas and pressure to the outside. According to the lightning arrester 1, the insulating cylinder 11
Since the weak point portion 14 is provided, even if the cover 4 shown in FIG. 9 is not provided, it is possible to prevent the lightning arrester 1 from exploding due to an increase in internal pressure due to the arc when a ground fault current exceeding the duty flows through the lightning arrester 1.

[0011]

However, the surge arrester 1 described above can prevent the surge arrester 1 from exploding due to an increase in internal pressure due to an arc when a ground fault current exceeding its duty flows, but the structure of the surge arrester 1 is limited. The lightning arrester 1 itself is not only complicated but also difficult to assemble, but also has the disadvantage that the lightning arrester 1 itself becomes huge.

For example, when assembling the internal components of the lightning arrester 1, the individual components of the operator, specifically, a plurality of non-linear resistors 6 and the upper and lower terminal electrodes 8 must be arranged and assembled manually. In order to integrate them, an insulating rod 9 and an insulating nut 10 are required. Further, when the lightning arrester inner element 2 is molded with the polymer insulator 3, an axial force is applied to the lightning arrester inner element 2 to fix the same, so that the lid 4 and the spring 5 are used to include unstable elements during assembly. .

Further, when a ground fault current exceeding the duty flows into the lightning arrester 1, the internal pressure increases due to the arc heat. However, when a strong insulating cylinder 11 is provided on the side of the polymer insulator 3,
The expanded hot gas moves up and down. Therefore, in order to prevent the lid 4 at the upper and lower ends from being broken and scattered due to the rise in the internal pressure, an opening portion must be provided in the lid 4, and further, a pressure release port 13 through which a high-temperature gas passes must be provided. For this reason, there is a problem that the number of parts is large, and that an uncertain element is included during assembly.

On the other hand, in order to prevent the pressure of the lightning arrester internal element 2 from increasing, the weak point portion 14 is formed by thinning a part of the insulating cylinder 11 surrounding the lightning arrester internal element 2 in order to release the pressure in the radial direction of the lightning arrester. Although it is necessary to wind the provided insulating tube 11 around the lightning arrester inner element 2, an expensive fiber reinforced plastic (FRP: fiberreinfor) is used as the insulating tube 11.
It is necessary to fix the upper and lower flanges with lids 4 using ced plastic).

Alternatively, an insulating material such as the insulating cylinder 11 may be filled with a curable additive to provide a function of molding individual parts. However, the cost of the curing agent is high, and the non-linear resistor 6 is required. Has a possibility that the conductive coupling becomes insufficient.

The present invention has been made to solve these problems. The number of parts constituting the lightning arrester has been reduced, the manufacturability has been improved and the size has been reduced, and a ground fault current exceeding the duty has been passed. It is an object of the present invention to provide a safe lightning arrester that does not explode and scatter even in a case.

[0017]

According to a first aspect of the present invention, there is provided a lightning arrester comprising: a joined body formed by stacking and joining a plurality of non-linear resistors mainly composed of zinc oxide by conductive joining;
A terminal metal electrode which is conductively joined to both ends of the joint;
A lightning arrester internal element formed integrally with the bonded object and the terminal metal electrode, an insulating coating covered with an outer peripheral surface of the lightning arrester internal element and having an opening, and an outer peripheral surface of the insulating coating. And a polymer insulator to be molded.

According to the present invention, a plurality of non-linear resistors mainly composed of zinc oxide are laminated and joined by conductive joining to form a joint, and a terminal electrode metal is provided at an end of the joint. Are electrically conductively bonded, and those all of which are firmly integrated are used as lightning arrester internal elements.

Conventionally, a lightning arrester having such a configuration has been developed. However, by simply stacking non-linear resistors, the strength is increased by forming an insulating coating on the outer peripheral surface of the stacked non-linear resistors. I had it. However, in the present invention, the lightning arrester internal element itself can have strength by conductively joining the non-linear resistors and the terminal electrode metal. For this reason, according to the present invention, not only is there no need for any component for fixing the lightning arrester internal elements inside the lightning arrester, but also the number of components constituting the lightning arrester can be reduced, and the manufacturability can be improved and the size can be reduced. it can.

In addition, by surrounding the integrated lightning arrester inner element with an insulating covering having an opening having excellent moisture resistance, partial discharge resistance and flame resistance, and molding it with a polymer insulator, Excessive operation causes the zinc oxide sintered body as a non-linear resistor to break through, and even if gas is generated due to arc generation and the internal pressure rises, gas is blown out from the hole in the radial direction and polymer The insulator can be partially destroyed to prevent the surge arrester from exploding.

According to a second aspect of the present invention, in the lightning arrester according to the first aspect, a conductive metal electrode is provided between the non-linear resistor and the non-linear resistor forming a joint of the lightning arrester internal elements. It is characterized by the following.

According to the present invention, a metal electrode having conductivity is provided between the non-linear resistor and the non-linear resistor in order to further strengthen the coupling force between the elements of the non-linear resistor. Are laminated and conductively bonded, and a terminal metal electrode is conductively bonded to the end of the bonded product, and the integrated one is used as an inner element of the lightning arrester. For this reason, the lightning arrester internal element has further strength. Further, an insulating cover is coated around the integrated lightning arrester inner element and molded with a polymer insulator. For this reason, the generated gas gushes from the opening of the insulating coating in the radial direction of the polymer insulator,
The polymer arrester can be prevented from exploding.

The invention according to claim 3 is the invention according to claim 1 or 2
In the lightning arrester described above, the insulating cover is an insulating sheet having a plurality of holes.

According to the present invention, by using an insulating sheet having a plurality of holes as an insulating cover, a safe lightning arrester that does not explode or scatter even when a ground fault current exceeding its duty flows is obtained. be able to.

According to a fourth aspect of the present invention, in the arrester according to the third aspect, the insulating cover is a mesh-shaped insulating sheet.

According to the present invention, the generated gas is blown out in the radial direction of the polymer insulator by winding a mesh-shaped insulating sheet around the integrated lightning arrester inner element, and the lightning arrester is explosively scattered. Can be prevented.

According to a fifth aspect of the present invention, in the lightning arrester according to the third aspect, the hole of the insulating sheet is circular.

In the present invention, a plurality of circular holes may be provided as holes in the insulating sheet, and the above-described effects can be obtained by winding the insulating sheet having the circular holes and molding with a polymer insulator. .

The invention according to claim 6 is the invention according to claim 1 or 2
In the lightning arrester according to the above, the insulating covering is a plurality of rod-shaped insulators which are arranged evenly in the axial direction of the lightning arrester internal element and the outer peripheral surface of the lightning arrester internal element, and a circle of the outer peripheral surface of the rod-shaped insulator and the lightning arrester internal element. And an elastic insulating tape wound around the circumferential direction at several places.

According to the present invention, by using an integrated lightning arrester internal element that is laminated and joined, a component for fixing the lightning arrester internal element becomes unnecessary. Also,
An axially long insulating rod is wound around the integrated lightning arrester inner element as a rod-shaped insulator, and an opening is formed by winding an insulating tape, and they are molded with a polymer insulator. For this reason, the generated gas is blown out from the gap between the insulating rod and the insulating tape in the radial direction of the polymer insulator, so that the lightning arrester can be prevented from explosively scattering.

[0031]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
This will be described with reference to FIG.

FIG. 1 is a sectional view schematically showing a lightning arrester.

As shown in FIG. 1, a plurality of non-linear resistors 20 mainly composed of zinc oxide are laminated and joined by conductive joining to form a joint 21. Terminal metal electrodes 22 are conductively joined to both ends of the joint 21, and the joint 21 and the terminal metal electrode 22 are firmly integrated to form a lightning arrester internal element 23. This lightning arrester internal element 23
Is covered with an insulating sheet 25 having openings 24, and a polymer insulator 26 is molded on the outer peripheral surface of the insulating sheet 25. Note that a gap 27 between the polymer insulator 26 and the lightning arrester inner element 23 is provided with a sealing 27 for securing confidentiality.

FIG. 2 is a sectional view schematically showing an arrester provided with metal electrodes. Since this lightning arrester has substantially the same configuration as the lightning arrester shown in FIG. 1, the corresponding parts in FIG. 2 are assigned the same reference numerals as in FIG.

The lightning arrester shown in FIG. 2 is provided with a conductive metal electrode 28 between the non-linear resistors 20 of the lightning arrester internal element 23 shown in FIG.

FIG. 3 is a sectional view schematically showing a lightning arrester using a mesh-shaped insulating sheet as an insulating cover. Since this lightning arrester has substantially the same configuration as the lightning arrester shown in FIG. 1, the corresponding parts in FIG. 2 are assigned the same reference numerals as in FIG.

As shown in FIG. 3, the outer peripheral surface of the lightning arrester inner element 23 is covered with a mesh-like insulating sheet 29,
Further, a polymer insulator 26 is provided on the outer peripheral surface of
Is molded.

FIG. 4 is a sectional view schematically showing a lightning arrester provided with metal electrodes in the lightning arrester of FIG. Since this lightning arrester has almost the same configuration as the lightning arrester shown in FIG.
The same reference numerals as in FIG. 2 denote the corresponding parts, and a description thereof will be omitted.

The lightning arrester shown in FIG. 4 is provided with a conductive metal electrode 28 between the non-linear resistors 20 of the lightning arrester internal element 23 shown in FIG.

FIG. 5 is a sectional view schematically showing a lightning arrester using an insulating sheet provided with a circular hole as an insulating cover.
Note that this lightning arrester has substantially the same configuration as that of the lightning arrester shown in FIG. 1, and therefore, the corresponding portions in FIG.

The lightning arrester shown in FIG.
An insulating sheet 31 having a circular hole 30 in the opening was used on the outer peripheral surface of the substrate.

FIG. 6 is a cross-sectional view schematically showing an arrester provided with metal electrodes in the arrester of FIG. This lightning arrester has almost the same configuration as the lightning arrester shown in FIG.
The same reference numerals as in FIG. 2 denote the corresponding parts, and a description thereof will be omitted.

The lightning arrester shown in FIG. 6 is provided with a conductive metal electrode 28 between the nonlinear resistors 20 of the lightning arrester internal element 23 shown in FIG.

In the present embodiment, according to the lightning arrester shown in FIG. 1, since all of the lightning arrester internal elements 23 are firmly integrated, the assembly is greatly simplified and the work becomes easy. Therefore, since the lightning arrester internal element 23 is fixed, parts such as the spring 5, the insulating rod 9, and the insulating nut 10 shown in the conventional example of the lightning arrester of FIG. 9 become unnecessary, and a structurally stable lightning arrester internal element 23 is obtained. Can be Therefore, when assembling the surge arrester, the surge arrester internal element 23 with little variation can be easily obtained without depending on the experience of the worker.

In addition, since the insulating sheet 25 having excellent corona resistance, flame resistance and moisture resistance and having openings is wound in the circumferential direction of the lightning arrester inner element 23, the lightning arrester rarely operates in a non-linear manner due to a rare occurrence of excessive responsibility. Even if the resistor 20 breaks through and the gas is generated due to the arc and the internal pressure increases, the gas blows out from the opening 24 of the insulating sheet 25 in the radial direction, and the polymer insulator 26 is partially damaged. It is possible to prevent the lightning arrester from explosively scattering only by itself.

Further, according to the lightning arrester shown in FIG. 2, the coupling force between the non-linear resistors 20 can be further strengthened. By expelling the ascent in the radial direction, it is possible to prevent the surge arrester from exploding.

In the lightning arrester shown in FIGS. 3 and 4,
Using a mesh-shaped insulating sheet 29 as an insulating coating,
According to the lightning arrester shown in FIGS. 5 and 6, the insulating sheet 31 provided with the circular holes 30 is used. Therefore, according to the present embodiment, even if the opening to be wound around the lightning arrester internal element 23 has a mesh shape shown in FIGS. 3 and 4 or a circular hole shown in FIGS. The pressure rise at the time can also be prevented from explosive scattering of the arrester by squirting in the radial direction.

Other Embodiments (FIGS. 7 and 8) In this embodiment, FIGS. 7 and 8 show a case where an insulating cover is formed by using an insulating rod and an insulating tape.
This will be described with reference to FIG.

FIG. 7 is a sectional view schematically showing a lightning arrester using an insulating rod and an insulating tape as an insulating covering. In addition, about the structure similar to the lightning arrester shown in FIG. 1, the corresponding part of FIG. 7 is attached | subjected with the same code | symbol as FIG. 1, and description is abbreviate | omitted.

As shown in FIG. 7, a plurality of non-linear resistors mainly composed of zinc oxide are laminated and joined by conductive joining to form a joint (not shown). Terminal metal electrodes 22 are conductively bonded to both ends of the joint, and the joint and the terminal metal electrode 22 are firmly integrated to form a lightning arrester internal element 23.

On the outer peripheral surface of the lightning arrester internal element 23, a plurality of insulating rods 32, which are rod-shaped insulators, are evenly arranged in the axial direction of the lightning arrester internal element 23. Four elastic insulating tapes 33 are wound around the outer periphery of the insulating rod 32 and in the circumferential direction of the lightning arrester inner element 23. Further, the polymer insulator 26 is molded on the outer peripheral surface of the insulating rod 32 and the insulating tape 33.

FIG. 8 is a sectional view schematically showing a lightning arrester provided with metal electrodes in the lightning arrester of FIG. In addition, about the structure similar to the lightning arrester shown in FIG.
The same reference numerals are given and the description is omitted.

The lightning arrester shown in FIG.
A metal electrode 28 having conductivity is provided between a non-linear resistor (not shown).

Therefore, according to this embodiment, even when the insulating rod 32 is compressed radially with the insulating tape 33 and fixed to form the opening as shown in FIGS. In addition, the pressure rise at the time of the ground fault can be prevented from explosively scattering by squirting in the radial direction.

[0055]

As described above, according to the lightning arrester according to the present invention, since the lightning arrester is firmly integrated, the number of parts is reduced during assembly, so that the work becomes easy, and the lightning arrester is easily transported and installed after assembly. As a result, there is no uncertain element such as the internal components of the lightning arrester dropping out, and pressure is ejected in the radial direction even in the case of over-compliance operation, so that explosive scattering of the lightning arrester can be prevented and a safe lightning arrester can be provided.

[0056]

[Brief description of the drawings]

[0057]

FIG. 1 is a schematic sectional view showing an embodiment of a lightning arrester according to the present invention.

[0058]

FIG. 2 is a schematic sectional view showing an embodiment of the lightning arrester provided with electrodes in the lightning arrester shown in FIG. 1 in the present invention.

[0059]

FIG. 3 is a schematic sectional view showing an embodiment of a lightning arrester using a mesh-shaped insulating sheet in the present invention.

[0060]

FIG. 4 is a schematic sectional view showing an embodiment of the lightning arrester provided with electrodes in the lightning arrester shown in FIG. 3 in the present invention.

[0061]

FIG. 5 is a schematic sectional view showing an embodiment of an arrester improved from the arrester shown in FIG. 1 in the present invention.

[0062]

FIG. 6 is a schematic sectional view showing an embodiment of the lightning arrester provided with electrodes in the lightning arrester shown in FIG. 5 in the present invention.

[0063]

FIG. 7 is a schematic sectional view showing another embodiment of a lightning arrester according to the present invention.

[0064]

8 is a schematic cross-sectional view showing one embodiment of the lightning arrester provided with electrodes in the lightning arrester shown in FIG. 7 in the present invention.

[0065]

FIG. 9 is a cross-sectional view schematically showing a conventional lightning arrester.

[0066]

FIG. 10 is a cross-sectional view schematically showing a conventional lightning arrester.

[0067]

[Explanation of symbols]

 REFERENCE SIGNS LIST 20 Non-linear resistor 21 Joint 22 Terminal metal electrode 23 Arrester inner element 24 Opening 25 Insulating sheet 26 Polymer insulator 27 Sealing 28 Metal electrode 29 Mesh-shaped insulating sheet 30 Circular hole 31 Insulating sheet 32 Insulating rod 33 Insulating tape

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5E034 EA07 EB01 EB03 EB04 EB05 EC01 ED03 5G331 AA03 BB17 BB31 CA04 CA05 CB06 DA02 DA03 EB07

Claims (6)

[Claims] 1. A joint formed by laminating and joining a plurality of non-linear resistors mainly composed of zinc oxide by conductive joining, and a terminal metal electrode conductively joined to both ends of the joint. A lightning arrester internal element formed integrally with the bonded article and the terminal metal electrode, an insulating coating covering an outer peripheral surface of the lightning arrester internal element and having an opening, and an outer peripheral surface of the insulating coating A lightning arrester characterized by comprising a polymer insulator molded into a lightning arrester. 2. The lightning arrester according to claim 1, wherein a conductive metal electrode is provided between the non-linear resistor and the non-linear resistor forming a joint of the lightning arrester internal elements. . 3. The lightning arrester according to claim 1, wherein the insulating cover is an insulating sheet having a plurality of holes. 4. The lightning arrester according to claim 3, wherein the insulating covering is a mesh-shaped insulating sheet. 5. The lightning arrester according to claim 3, wherein the hole in the insulating sheet is circular. 6. The lightning arrester according to claim 1, wherein the insulating covering is a plurality of rod-shaped insulators which are arranged evenly in an outer peripheral surface of the lightning arrester inner element and in an axial direction of the lightning arrester inner element, and the rod-shaped insulator. And an elastic insulating tape wound around the outer circumferential surface of the lightning arrester at several locations in the circumferential direction of the inner element of the lightning arrester.