JPS63313804A - Lightning arrestor - Google Patents

Abstract

PURPOSE:To increase the mechanical strength of an insulating tube by forming the outermost layer with a weatherproof thermal contractile material, and the innermost layer for contact-holding of a lightning element with an insulating thermal contractile material. CONSTITUTION:An insulating tube 20 has a multilayer construction; the outermost layer 201 formed of a high-weatherproof thermal contractile material, the innermost layer 202 formed of a high-insulation thermal contractile material, and a thermal contractile reinforcing layer 203 interposed therebetween to increase its mechanical strength. Within the tube 20, a plurality of lightning arresting elements 25 are located in series which are electrically connected with an electrode 24 just below a line-side electrode terminal 21, and a pressure mounting support 26 is also located consisting of an elastic spring 26a and a holder 26b between the line-side electrode 24 and the uppermost lightning arresting element 25 to provide energized holding with its elasticity. The mechanical strength is increased in this way resulting in long lifetime.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a lightning arrester in which an insulator tube housing a lightning arrester element made of a material with nonlinear voltage-current characteristics has a multilayer structure.
It is especially used in lightning arresters for high-voltage overhead power transmission.

(Prior Art) As lightning arresters, lightning arresters for power distribution lines and power transmission lines are known, and both of these have a lightning arrester element housed in an inner cylindrical insulator tube.

The lightning arrester is initially molded mainly from silicon carbide (SiC), but when using this lightning arrester, a series gap must be provided, which causes a delay in discharge due to response characteristics and discharge performance. However, as a substitute for this, a lightning arrester element made of a fired product mainly composed of zinc oxide (ZnO) was developed and has come to be used in this type of lightning arrester.

Fired lightning arrester elements are mainly made of zinc oxide (ZnO).
As is well known, the voltage-current characteristics have non-linear resistance characteristics, which has many significant benefits such as eliminating the need for a series gap, improving the performance of the lightning arrester, and preventing deterioration of the lightning arrester itself. It is.

Hereinafter, a conventional lightning arrester will be explained based on the half-cut vertical front view of FIG.

The insulator tube (1) has a cylindrical shape made entirely of ceramic material, and on its outer periphery is an annular cap (
1a) are formed by arranging a plurality of strips at equal intervals, and both ends thereof are open.

Inside the insulator tube (1), a conductive connection plate (electrode )(3)
is inserted and arranged, and furthermore, the conductive connection plate (3)
Immediately below the energizing side electrode (4) is the conductive connection plate (3).
A support device (5) having an elastic coil spring is provided, which is electrically connected to the energizing side electrode and surrounds the energizing side electrode.

The pressure support device (5) accommodates two lightning arrester elements (6) arranged in series, each of which is fixed by the biasing holding force of an elastic coil spring of the pressure support device, and has a ground side opening of the insulator fil. It is electrically connected to the bottom metal fitting (7) that seals it.

The bottom metal fitting (7) is provided with an annular seal ring (8) inside thereof to prevent moisture from entering into the insulator tube (11). electrode terminals (9) are coupled.

Symbol αO) is the line side electrode terminal (2) of the insulator fl+
In addition to protecting the terminal,
The insulator pipe (1) is sealed with a sealant (sealing material such as rubber) etc. (12) interposed in order to prevent moisture from entering through the insulator pipe opening.
It is fitted on the top edge of the .

Note that reference numeral (11) is a support band for supporting the insulator tube (1) and attaching it to an overhead power transmission line or the like.

As mentioned above, the lightning arrester (6) is made of zinc oxide (ZnO
), scandium (Sc), and yttrium (
Zinc oxide ceramics are made by adding rare earth elements such as Y) and trace amounts of metal oxides, and are fired as zinc oxide ceramics.The voltage-current characteristics are made of a material that has non-linear resistance characteristics. 4), but there is also a structure in which these lightning arrester elements +61 +61 are housed in a cylindrical insulator.

(Problems to be Solved by the Invention) The lightning arrester having the above configuration uses a lightning arrester element formed mainly of zinc oxide (ZnO) and having non-linear resistance characteristics in voltage and current characteristics. There is no need to use a series gap, and the performance of the lightning arrester can be improved.

(2) There is no follow current during operation duty and there is no deterioration of the lightning arrester element.

(3) It can be made smaller and lighter than conventional lightning arresters.

(4) It becomes possible to develop a molded lightning arrester, and the conditions for its use as a lightning arrester are expanded.

It has significant points such as:

However, in order to obtain a large discharge withstand capacity, the above-mentioned lightning arrester elements are strongly required to have uniformity inside the lightning arrester element, and for this reason, conditions such as mixing, crushing, and molding of the raw material powder are subject to strict quality control. With the capabilities of this type of manufacturing equipment, it is impossible to use the lightning arrester as a single unit in an insulator tube.
Since the functions of lightning arresters cannot be fully demonstrated, multiple lightning arresters are housed and used as split types. In this case,
It is necessary to electrically connect the lightning arrester elements so that they are almost integral with each other, but in the conventional lightning arrester described above, this point is solved by maintaining the bias using a support device with a built-in elastic spring. We are trying to solve this problem.

However, this type of lightning arrester is used for power distribution and heavy transmission, and although it does not pose many problems for power distribution, when it is used as lightning protection equipment for power transmission in extremely harsh natural environments such as mountainous areas, , the entire lightning arrester swayed due to other effects.

They are often subjected to vibrations, and the arrester, especially the insulator tube, is subject to tensile and bending stresses.

Therefore, the insulator tube of the lightning arrester must be made of a material with high tensile and bending strength, and it is also necessary to prevent the lightning arrester element housed in the insulator tube from shifting, and to improve its insulation properties. There is a need.

However, the above-mentioned lightning arrester did not satisfy the above points.

(Objective of the present invention) As described above, the present invention provides an insulator tube for a lightning arrester with increased mechanical strength.

(Means for Solving the Problem) A track-side electrode terminal and a ground-side electrode terminal are inserted into openings at both ends of an insulator tube, and a line electrically connected to the track-side electrode terminal is inserted into the insulator tube. A side electrode, a pressure device that applies a biasing and holding force to the lightning arrester, a lightning arrester that is biased and held by the lightning arrester, and a grounding side electrode that is electrically connected to the lightning arresting device and the grounding side electrode terminal, respectively. In addition, the outermost layer of the insulator tube is formed of a heat-shrinkable material that has weather resistance and heat-shrinkability, and the innermost layer that tightly holds the lightning arrester element is formed of a heat-shrinkable material that has insulation properties. The problem is solved by providing a lightning arrester having a multi-layered structure or a three-layer structure made of an insulator tube with properties for radiation protection and mechanical strength reinforcement.

(Example) An example of the present invention will be described in detail based on the conceptual diagram shown in FIG. 1 showing the entire installation apparatus for power transmission lines and the longitudinal sectional front view shown in FIG.

As shown in the conceptual diagram in Figure 1, the entire erection equipment consists of a steel tower (
A suspension insulator (D) is suspended from the arm part (B1) of B) by a hanging metal fitting (C), and an electric wire (F) is gripped and fixed at the lower end of the suspension insulator (D) by a gripping metal fitting (E). and
Further, the gripping fitting (E) is provided with an arcing horn (G) in an upwardly inclined manner, and the lightning arrester (A) of the present invention is attached to the hanging fitting (C) via the mounting fitting (H). G) When a lightning surge occurs on the wire (F), this voltage is applied to the installation equipment, but in this case, the current passes through the gripping bracket (E) and the arcing bone (G) to the lightning arrester. (A), hanging metal fittings (C) and steel tower (B)
It is then grounded to the earth.

Next, the structure of the lightning arrester (A) of the present invention will be specifically explained based on FIG. 2.

A track side electrode terminal (2
1) is inserted with its pointed end protruding so that it can be electrically connected to the energized line, and on the other hand, a grounding side electrode terminal (22) is installed at the bottom opening (grounding side) of the insulator tube (20). The outermost layer (201) of the insulator tube (20) is made of silicone resin, fluorinated resin, cross-linked polyethylene, epoxy resin, or weather-resistant rubber. The innermost layer (202) is made of a heat-shrinkable insulating material with high insulation properties, and the outermost layer (201)
It has a multilayer structure in which a heat-shrinkable reinforcing layer (203) made of polypropylene or the like is formed between the innermost layer (202) and the innermost layer (202) to reinforce mechanical strength.

Furthermore, the line side electrode terminal (
An electrode (24) made of a conductive material is arranged directly under the electrode (21) in an electrically connected state.
) are arranged in series, and the lightning arrester (25) disposed at the lowest position of the lightning arrester (25) is electrically connected to the ground side. electrode(
23) are arranged so as to be electrically connected.

The plurality of lightning arrester elements (25) (25)... are held and fixed between a track side electrode (24) and a ground side electrode (23) installed in the insulator tube (20). As a fixing means, it may be installed in an insulating cylinder with high mechanical strength such as reinforced plastic, but in this embodiment, the line side electrode (24) and the lightning arrester (2
5) between the elastic spring (26a) and the holder (26b).
A pressure device (26) consisting of
26) is biased and held by the elastic force.

The pressure point force of the pressure support device (26) on the lightning arrester element (25) is:
Normally, the pressure is applied at a strength of approximately 60 kg/ct, but in this example, the pressure point force is approximately 60%, that is, 30 kg/ct.
kg/ci~40kg/cn! The pressure point force is set in the range of .

Furthermore, although the insulator tube (20) has several bulges formed in this embodiment, it is preferable not to form these bulges for salt resistance.

The lightning arrester of the present invention is constructed as described above, and the insulator tube (20) that accommodates the power line side electrode, the electrode terminal, the arrester element 1, the grounding side electrode, etc. is made of a heat-shrinkable material. The multi-layered structure (three layers in this example) is formed, and after accommodating the above-mentioned equipment, it is heat-shrinked and the above-mentioned equipment is crimped and fixed.

The code (2nd) is a track side cover fitting, and a side road side electrode terminal (2) that protrudes into the track side opening of the insulator tube (20).
A sealing agent (29) and a sealing ring (30) are fitted inside the insulating pipe (20) to contain the above-mentioned Code (32) electrically connected to the track side electrode terminal (21) and connected to the track side electric wire (31)
is a safety cap that is fitted to enclose the track side cover (28).

Reference numeral (33) denotes a sealing metal fitting that seals the ground side opening (bottom surface) of the insulator tube (20), and includes a sealing ring (33).
4) to prevent the intrusion of harmful substances such as rainwater and dust from the ground side opening of the insulator pipe, and also prevent the intrusion of harmful substances such as rainwater and dust from the ground side opening of the insulator pipe (20). ) are electrically connected.

Reference numeral (35) is a support band for attaching the insulator pipe (20) to an overhead power transmission line or the like.

The structure of the lightning arrester shown in the above embodiment is as described above, but in order to improve the airtightness inside the insulator tube (20), a thermosetting resin (melamine resin, phenol resin, etc.) is used as the inner layer of the insulator tube (20).
202) It is also possible to adopt a configuration in which the liquid is filled into the inside.

(Effects of the Invention) By adopting the above configuration, the lightning arrester (A) of the present invention can maintain and maintain the original function of the lightning arrester, which always maintains airtightness and prevents the lightning arrester from deteriorating due to moisture absorption, etc. Needless to say, the insulators are made of a multi-layered structure made of heat-shrinkable material that has strong mechanical strength properties, so they have sufficient weather resistance even when installed on power lines that are susceptible to rain, wind, and vibration. In addition to being significant in that it exerts a lot of force and dramatically improves its service life, the insulator tube itself shrinks due to heating and can firmly hold the lightning arrester, etc. housed inside so that it does not shift, preventing deterioration of the lightning arrester. can.

Furthermore, since the inside of the insulator tube can be maintained in a more airtight state, it is possible to completely prevent moisture and dust from entering the insulator tube, thereby eliminating corona discharge inside the insulator tube, which has superior effects compared to conventional lightning arresters. It is something.

[Brief explanation of the drawing]

Fig. 1 is a conceptual diagram showing how the lightning arrester of the present invention is installed for power transmission, Fig. 2 is a vertical cross-sectional front view showing an embodiment of the lightning arrester of the present invention, and Fig. 3 is a half-cut vertical cross-sectional view showing a conventional lightning arrester. It is a diagram. The names of the codes are as follows. (8) is the lightning arrester, (20) is the insulator tube, (201) is the outermost layer of the insulator tube, (202) is the innermost layer of the insulator tube, (203)
) is the middle layer of the insulator. (21) is the line side electrode terminal, (22) is the ground side electrode terminal. (23) (24) are electrodes, (25) (25)...
(26) is the lightning arrester, (26) is the railing device, (2B) is the track side cover fitting, (33) is the insulator tube bottom sealing fitting, (32)
) is a safe camp. Patent Applicant Otowa Electric Industry Co., Ltd. Agent Patent Attorney Akira Kanemaru -2 No. 211J A), I 2E/ 3v 2! a 25b' sa ra, +2)
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.・2riZ)2 25 E25゜shi1 ・q −/″F A■ layer

Claims (4)

[Claims] (1) A line-side electrode terminal and a ground-side electrode terminal are inserted into the openings at both ends of the insulator tube, and within the insulator tube there is a line-side electrode electrically connected to the line-side electrode terminal, and an attachment for the lightning arrester element. In addition to accommodating a lightning arrester that imparts a force-retaining force, a lightning arrester element that is biased and held by the lightning arrester, and a ground side electrode that is electrically connected to the lightning arrester element and the ground side electrode terminal, the above-mentioned The insulator has a multilayer structure in which the outermost layer is made of a heat-shrinkable material that has weather resistance and heat-shrinkability, and the innermost layer that tightly holds the lightning arrester element is made of a heat-shrinkable material that has insulation properties. A lightning arrester characterized by: (2) The lightning arrester according to claim 1, characterized in that a plurality of bulk portions are formed on the outer periphery of the insulator tube, the tips of which are surface-processed. (3) The outermost layer of the multilayered insulator is made of a heat-shrinkable material with high mechanical strength, the innermost layer is made of a heat-shrinkable material with insulation properties, and the intermediate layer between these outermost and innermost layers is made of a heat-shrinkable material with high mechanical strength. 2. The lightning arrester according to claim 1, wherein the lightning arrester has a three-layer structure made of a heat-shrinkable material for reinforcement of strength and mechanical strength. (4) The outermost layer of the insulator is made of a heat-shrinkable material with high mechanical strength, such as silicone resin, fluorinated resin, cross-linked polyethylene, epoxy resin, weather-resistant rubber, etc., and the middle layer is made of polypropylene, etc., for mechanical strength reinforcement. 2. The lightning arrester according to claim 1, wherein the heat-shrinkable material and the innermost layer are made of a heat-shrinkable material having insulating properties.