CN110459374B

CN110459374B - Explosion-proof lightning arrester

Info

Publication number: CN110459374B
Application number: CN201910348222.5A
Authority: CN
Inventors: 龙如飞
Original assignee: Cooper Electronic Technologies Shanghai Co Ltd
Current assignee: Cooper Electronic Technologies Shanghai Co Ltd
Priority date: 2019-04-28
Filing date: 2019-04-28
Publication date: 2020-11-03
Anticipated expiration: 2039-04-28
Also published as: CN110459374A

Abstract

The invention provides an explosion-proof arrester, comprising: a jacket; the insulating core body is arranged in the outer sleeve, the insulating core body comprises an insulating cylinder vertically arranged in the insulating core body, and an upper electrode, a first spring and a plurality of valve plates which are arranged in the insulating cylinder from top to bottom and are electrically connected, wherein the valve plates are electrically connected to a cushion block which is positioned below the valve plates through a second spring and is pressed to the inner surface of the outer sleeve, and a grounding bolt fastened to the cushion block, the cushion block is pressed to the inner surface of the outer sleeve through a clamping mechanism at least partially sleeved on the outer sleeve, and the joint of the cushion block and the outer sleeve is designed to be a pressure release part which is firstly damaged by high-pressure gas appearing in the lightning arrester. According to the mounting structure provided by the invention, the directional drainage of the lightning arrester can be realized, so that the explosion-proof function is realized.

Description

Explosion-proof lightning arrester

Technical Field

The invention relates to the field of lightning arresters, in particular to an explosion-proof separation lightning arrester with directional drainage.

Background

The lightning arrester is an electrical device which can release lightning or over-voltage energy in operation of electrical equipment, protect the electrical equipment from being damaged by instantaneous over-voltage, and cut off follow current without causing short circuit of system ground. The arrester is usually connected between the live conductor and ground, in parallel with the equipment to be protected. The lightning arrester is mainly used for reducing the amplitude of an invading flowing wave through the action of a parallel discharge gap or a nonlinear resistor, and reducing the overvoltage value borne by protected equipment, thereby protecting the power equipment. Specifically, when the protected equipment operates under normal working voltage, the lightning arrester can not act, is regarded as open circuit for the ground, and can act immediately once high voltage occurs and the insulation of the protected equipment is endangered, so that high voltage impact current is guided to the ground, the voltage amplitude is limited, and the insulation of electrical equipment is protected; when the overvoltage disappears, the lightning arrester can restore to the original state rapidly, so that the system can supply power normally.

After long-term exploration, various lightning arresters have been manufactured. Common types of lightning arresters include: an elbow type lightning arrester of a plug-in structure, for example, proposed by kubo corporation of america, has a structure of: the valve comprises a shielding outer sleeve, a valve core, an electrode, an external end cover and the like. The other type is a common structural mode of a rear-connected arrester, and the structure of the rear-connected arrester is as follows; the conductive shielding outer sleeve, the inner conductive layer, the electrode, the valve plate core, the weftless fabric layer, the outer end cover, the wiring terminal and the like.

At present, no matter a rear-connected type or elbow type lightning arrester is provided with an explosion-proof function after a lightning arrester core body is sleeved outside the lightning arrester. The explosion-proof function is divided into two types of hot melting and hot explosion, but the current lightning arrester is not provided with a drainage protection blasting device, so that when the lightning arrester is subjected to flashover due to factors such as aging and the like, pressure release cannot be oriented to form comminuted explosion, and personal injury accidents are often caused by high-pressure end explosion.

Accordingly, there is a need in the industry to improve at least one of the above-mentioned deficiencies of lightning arresters to meet the safety requirements of lightning arresters.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a directional drainage explosion-proof separation lightning arrester which can directionally release pressure and prevent personal safety accidents when the lightning arrester is separated.

According to an aspect of the present invention, there is provided an explosion-proof arrester including: a jacket; the insulating core body is arranged in the outer sleeve, the insulating core body comprises an insulating cylinder vertically arranged in the insulating core body, and an upper electrode, a first spring and a plurality of valve plates which are arranged in the insulating cylinder from top to bottom and are electrically connected, wherein the valve plates are electrically connected to a cushion block which is positioned below the valve plates through a second spring and is pressed to the inner surface of the outer sleeve, and a grounding bolt fastened to the cushion block, the cushion block is pressed to the inner surface of the outer sleeve through a clamping mechanism at least partially sleeved on the outer sleeve, and the joint of the cushion block and the outer sleeve is designed to be a pressure release part which is firstly damaged by high-pressure gas appearing in the lightning arrester.

Compared with the traditional lightning arrester, the explosion-proof lightning arrester can ensure that when high-temperature and high-pressure gas is generated in the lightning arrester, the cushion block positioned right below the lightning arrester is firstly flushed out so as to release the high-temperature and high-pressure gas accumulated in the lightning arrester, and the nonlinear resistance valve plate supported by the cushion block can be simultaneously released, so that the phenomenon that the nonlinear resistance valve plate is positioned in the insulating cylinder to form a high-voltage conductor and continuously discharge to cause the explosion of the lightning arrester can be prevented, the lightning arrester is safer and more stable, and the safety of an electric power system is effectively improved.

In a preferred embodiment, the clamping mechanism is a band with a fastener disposed around the jacket, wherein the clamping force of the band is adjustable via the tightening force of the fastener. Hereby, it is achieved in a simple, low-cost, easy-to-mass-manufacture manner that a pressure relief is formed between the spacer and the casing of the explosion-proof arrester, which pressure relief is first destroyed by the high-pressure gas present in the arrester.

In a preferred embodiment, the arrester is a back-end arrester.

In a preferred embodiment, the plurality of valve plates are made of a metal oxide having a non-linear resistance.

In a preferred embodiment, the spacer is made of aluminum. Thus, an arrangement is achieved in which high temperature and high pressure gas is destroyed when present in the arrester, thereby releasing the high temperature and high pressure gas to avoid formation of personal injury caused by a comminuted explosion, in a simple, low cost, easy to mass produce manner.

In a preferred embodiment, the outer casing is made of rubber.

In a preferred embodiment, at least one conductor connection is provided on the outer jacket, wherein the outer jacket can be grounded via the conductor connection. Therefore, the outer sleeve is always in an uncharged state, the potential damage of the induced voltage formed on the outer sleeve to operators is prevented, and the safety of the lightning arrester is improved.

In a preferred embodiment, the lower opening of the insulating cylinder is designed to be tapered, whereby an effective directed flow of high-temperature and high-pressure gases generated inside the arrester is achieved in a simple, low-cost, easy-to-mass-manufacture manner.

In a preferred embodiment, further comprising a ground wire fastened to the spacer block via a galvanized stainless steel washer and a ground bolt.

Additional features and advantages of the invention will be set forth in part in the description which follows, and in part will be apparent to those having ordinary skill in the art upon examination of the following, or may be learned from the practice of the invention.

Drawings

Embodiments of the invention are described in detail below with reference to the attached drawing figures, wherein:

fig. 1 shows a perspective view of an explosion-proof arrester according to the present invention;

fig. 2 shows a front view of an explosion-proof arrester according to the present invention;

fig. 3 shows a sectional view taken on a section a-a in fig. 2 of the explosion-proof arrester according to the present invention.

List of reference numerals:

1. lightning arrester

3. First spring

5. Second spring

7. Device connection interface

9. Cushion block

11. First gasket

13. Connecting bolt

1A. coat

2. Upper electrode

4. Valve plate

6. Clamping mechanism

8. Wire connecting part

10. Grounding wire

1B insulating core

1C insulating cylinder

12. Second gasket

R. pressure relief

Detailed Description

Referring now to the drawings, schematic aspects of the mounting structure of the coil terminal for the contactor and the mounting method thereof disclosed in the present invention will be described in detail. Although the drawings are provided to present some embodiments of the invention, the drawings are not necessarily to scale of particular embodiments, and certain features may be exaggerated, removed, or partially sectioned to better illustrate and explain the present disclosure. The position of some components in the drawings can be adjusted according to actual requirements on the premise of not influencing the technical effect. The appearances of the phrase "in the drawings" or similar language in the specification are not necessarily referring to all drawings or examples.

Certain directional terms used hereinafter to describe the drawings, such as "front," "back," "inner," "outer," "above," "below," and other directional terms, will be understood to have their normal meaning and refer to those directions as normally contemplated by the drawings. Unless otherwise indicated, the directional terms described herein are generally in accordance with conventional directions as understood by those skilled in the art.

The terms "first," "second," and the like, as used herein, do not denote any order, quantity, or importance, but rather are used to distinguish one element from another.

The explosion-proof arrester according to the invention is shown in various views in fig. 1-3, wherein a back arrester is given here as an example, but it will be clear to a person skilled in the art that the inventive concept of the invention is equally applicable to an elbow arrester, and therefore the scope of protection of the invention should not be limited to the back arrester given as an example.

As shown in fig. 1, there is shown a back arrester 1 comprising: an outer sleeve 1A, wherein the outer sleeve is preferably made of silicon rubber and the like; and an insulating core 1B installed in the outer sleeve 1A, wherein as shown in fig. 3, the insulating core 1B is substantially T-shaped and includes an insulating cylinder 1C vertically disposed therein, and an upper electrode 2, a first spring 3, and a plurality of valve plates 4 electrically connected to each other and installed in the insulating cylinder 1C from top to bottom. Further, openings are formed at both ends of the upper portion of the insulating core, and in particular, an equipment connection port 7 for inserting an external electric equipment is provided at one side thereof, as shown in fig. 3, wherein the equipment connection port 7 is communicated with the upper electrode 2. Thus, in use, an external electrical device can be inserted with its tip into the device connection port 7 to electrically connect with the upper electrode 2.

As shown in fig. 3, a plurality of voltage nonlinear resistance valve plates 4, here, for example, 3, are arranged in an insulating cylinder 1C in a stacked manner. Among them, a zinc oxide (ZnO) -based material as a ceramic material is preferably used for the base of the voltage nonlinear resistor. Specifically, a sintered body formed by adding a subcomponent formed of oxides of bismuth (Bi), antimony (Sb), nickel (Ni), cobalt (Co), manganese (Mn), chromium (Cr), silicon (Si), and the like, water and an organic binder to zinc oxide (ZnO) as a main component, sufficiently stirring them, forming particles by a spray dryer, etc., molding, and firing may be used as the base.

Preferably, a high-resistance material for preventing surface flashover is applied to the side surface of the sintered body as necessary, and the sintered body is baked again to form a high-resistance layer. Then, both end faces of the sintered body are polished to attach an electrode outer layer film, whereby a voltage nonlinear resistor suitable for the present invention can be manufactured.

In order to ensure that the upper end of the voltage nonlinear resistance valve plate 4 accommodated in the insulating outer cylinder 1 always keeps conflict with the upper electrode 3; a conductive first spring 3 is disposed between the upper electrode 2 and the resistance valve plate 4, and further, the voltage nonlinear resistance valve plate 4 is electrically connected to a pad 9 which is located below the voltage nonlinear resistance valve plate and is pressed to the inner surface of the casing 1A and a grounding bolt 13 fastened to the pad 9 via a conductive second spring 5, wherein one end of the second spring 5 is abutted against and electrically connected to the nonlinear resistance valve plate 4, and the other end of the conductive spring 5 is abutted against the pad 9 so as to be electrically connected thereto, and in order to ensure that the conductive spring 5 does not topple undesirably during use, it is preferable that a protrusion portion conforming to the conductive spring 5 is disposed on the pad. Therefore, the first and

second springs

3 and 5 which are arranged in series and can conduct electricity can provide an elastic force to enable the nonlinear resistance valve plate 4, the upper electrode 3 and the cushion block 9 to keep a conducting state, and therefore the lightning arrester can be kept to operate stably.

The spacer 9 is here made of aluminium. Compared with other metals and alloys, the aluminum block has the following advantages: low density, low melting point and low cost. Since the spacer 9 in the present invention mainly serves to support the resistive valve sheet 4 and serves as a lower electrode for grounding or connecting to a ground wire, and the spacer 9 is required to be damaged when high-temperature and high-pressure gas exists in the arrester 1 so as to release the high-temperature and high-pressure gas to avoid personal injury caused by the formation of a shattered explosion, repeated experiments prove that the technical effect of using a spacer made of aluminum is optimal. Of course, a spacer made of other materials is also possible as long as it can satisfactorily support the resistive sheet and serve as the lower electrode. Furthermore, a counter bore into which a ground bolt is screwed is provided on the side of the spacer 9 facing away from the second spring 5.

As further shown in fig. 3, the spacer 9 is pressed against the inner surface of the outer jacket 1A below the resistance valve plate 4 in such a way that the spacer 9 is first inserted into the inner surface of the outer jacket 1A with a clearance fit, and then the clip 6 with the fastening means arranged around the outer jacket 1A is placed on the outer jacket 1A, preferably the clip 6 is made of stainless steel. By an operator tightening the fastener on the clamp 6 with a certain force, the clamp 6 is tightened along the outer periphery of the jacket 1A and exerts a certain pressing force on the outer periphery of the jacket 1A, which causes the jacket 1A to contract inwardly to achieve an interference fit with the spacer 9. The force of this pressing can be adjusted via the force of tightening the fastener, which is sufficient to cause the spacer 9 to be held at the lower end of the casing 1A against the elastic force of the first and second springs and the weight of the plurality of resistance plates 4, where, as described below, the junction of the spacer 9 and the casing 1A is designed as a pressure relief portion R that is first destroyed by the high-pressure gas present in the arrester. It is pointed out here that although the clamping mechanism is shown in fig. 3 in the form of a clamp, other forms of clamping mechanisms, such as clamps or jaws, are feasible alternatives.

It is further preferable that the lower opening of the insulating cylinder 1C is designed to be tapered as shown in fig. 3, which is more advantageous to guide the block 9 and various components (such as the spring and the resistance sheet 4) inside the insulating cylinder when the block is blown away by the high-temperature and high-pressure gas, which is more advantageous to improve the safety of the arrester of the present invention.

Preferably, the spacer 9 may achieve grounding of the arrester via a grounding wire 10, as shown in fig. 3, and the grounding wire 10 may be fastened to the spacer 9 by a grounding bolt 13 via a washer 11 and a lock washer 12 made of galvanized stainless steel. By such an arrangement, a reliable grounding of the arrester can be achieved and adverse effects of external environment and dust on the grounding performance are prevented.

Preferably, at least one conductor connection 8 is arranged on the outer circumference of the outer casing 1A, wherein the conductor connection 8 can also be grounded via a ground line, which ensures that the outer casing 1A of the arrester 1 is always at ground voltage without an induced voltage, which further ensures the personal safety of the operator.

As shown in fig. 1 to 3, according to the present invention, the upper electrode 2, the nonlinear resistance valve plate 4, the spacer 9 and the grounding bolt 13 are arranged from top to bottom, and the spacer 9 and the nonlinear resistance valve plate 4 are elastically and conductively contacted via the first spring 3 and the second spring 5, so that the nonlinear resistance valve plate 4 can effectively collide with the upper electrode 2 to be electrified, and thus the external electrical device inserted into the device connecting interface 7 is grounded via the grounding bolt 13 or the grounding wire 10, thereby achieving the purpose of lightning protection. In the event of failure of the arrester, such as the generation of high-temperature, high-pressure gas inside, since the spacer 9 is provided in the form of an interference fit with the casing 1A rather than a mechanical connection, a pressure release part R which is firstly damaged by high-pressure gas appearing in the lightning arrester is arranged between the cushion block 9 and the outer sleeve 1A, and the characteristic of guiding the high-temperature high-pressure gas by utilizing the orientation of the insulating cylinder 3, when the arrester is self-exploded, the pressure in the insulating cylinder 3 is suddenly increased to cause the pressure release part R to be separated, so that the cushion block 9 is downwards flushed out from the outer sleeve 1A and falls off, thereby releasing the nonlinear resistance valve plate 4 and the grounding end 8, preventing the nonlinear resistance valve plate 4 from forming a high-voltage conductor in the insulating outer cylinder 1 to continuously discharge, causing the accident of explosion of the lightning arrester, the lightning arrester is safer and more stable, and the safety of a power system is effectively improved.

It is to be understood that while the specification has been described in terms of various embodiments, it is not intended that each embodiment comprises a separate embodiment, and such descriptions are provided for clarity only and should be taken as a whole by those skilled in the art, and that the embodiments may be combined to form other embodiments as will be apparent to those skilled in the art.

The above description is only an exemplary embodiment of the present invention, and is not intended to limit the scope of the present invention. Equivalent alterations, modifications and combinations will occur to those skilled in the art without departing from the spirit and principles of the invention.

Claims

1. An explosion-proof arrester, characterized by comprising:

a jacket;

an insulating core body arranged in the jacket, wherein the insulating core body comprises an insulating cylinder vertically arranged in the insulating cylinder, and an electrically connected upper electrode, a first spring and a plurality of valve plates which are arranged in the insulating cylinder from top to bottom, wherein the valve plates are electrically connected to a cushion block which is positioned below the valve plates and is pressed to the inner surface of the jacket through a second spring, and a grounding bolt fastened to the cushion block,

wherein the pad is pressed against the inner surface of the casing via a clamping mechanism at least partially fitted over the casing, wherein the connection of the pad to the casing is designed as a pressure relief that is first destroyed by high-pressure gas present in the arrester, the clamping mechanism being a band with a fastener arranged around the casing, wherein the clamping force of the band is adjustable via the tightening force of the fastener; the lightning arrester is a rear-connection type lightning arrester, wherein an equipment connecting interface for inserting external electrical equipment is arranged at the upper part of the insulating core body, and the equipment connecting interface is communicated with the upper electrode;

wherein the lower opening of the insulating cylinder is designed to be tapered.

2. An explosion-proof arrester as claimed in claim 1, characterized in that the clip is made of stainless steel.

3. The explosion proof arrester as claimed in claim 1, wherein the plurality of valve plates are made of metal oxide having a non-linear resistance.

4. An explosion-proof arrester as claimed in claim 1, characterized in that the spacer is made of aluminium.

5. An explosion-proof arrester as claimed in claim 1, characterized in that the casing is made of rubber.

6. Explosion-proof arrester as claimed in claim 1, characterized in that at least one conductor connection is provided on the outer jacket, wherein the outer jacket can be earthed via the conductor connection.

7. The explosion proof arrester of claim 1 further comprising a ground wire secured to the spacer block via a galvanized stainless steel washer and a ground bolt.