CN2299377Y

CN2299377Y - Explosion-proof device of lightning protector

Info

Publication number: CN2299377Y
Application number: CN 97210721
Authority: CN
Inventors: 郭道林
Original assignee: Individual
Current assignee: Individual
Priority date: 1997-01-26
Filing date: 1997-01-26
Publication date: 1998-12-02
Anticipated expiration: 2007-01-26

Abstract

The utility model provides an explosion-proof device of lightning protector, composed of a conducting device, a trip gear, a coat and a base. The conducting device comprises an upper screw bolt electrode, a shorting copper strip, a copper electrode, a zinc oxide voltage-sensitive resistor valve block and a lower screw bolt electrode; the trip gear comprises a resistor, a tripping electrode, a zinc oxide voltage-sensitive resistor valve block, a copper electrode, a pressing dragline and a tripping spring. While in use, the utility model can be connected in series between an electrified wire netting cable and an arrester. The utility model enables the arrester to avoid explosion due to the excessive heating, simultaneously without affecting the overvoltage protection ability of the arrester so as to improve the assurance coefficient of the electrified wire netting and guarantee the safety in production of the electrical power system.

Description

The lightning arrester explosion-protection equipment

The utility model relates to the explosion-protection equipment of lightning arrester.

Along with developing rapidly of China's electric utility, the electrical network coverage rate is increasing, and electric pressure is more and more higher, and is also more and more higher to the requirement of electric power netting safe running.Begin from the eighties,, develop into gapless metal-oxide lighting arrester by traditional general valve arrester as the lightning arrester of the main protective device of electrical network.The use of this lightning arrester improves the coefficient of safety of electrical network greatly.But, because it directly is connected between electrical network and the earth, bear the influence of power-frequency voltage for a long time, chargeability is too high, and after use a period of time, its power loss increases gradually, finally causes puncturing.After the puncture, lightning arrester is short-circuit condition, absorbs big energy, and is overheated and explode, and the safety of other electric equipment around having a strong impact on causes great threat for the safety in production of electric power system.

The purpose of this utility model is to provide a kind of lightning arrester explosion-protection equipment that can make lightning arrester avoid thermal explosion.

The utility model is realized in the following ways.

The utility model is made of conducting device, trip gear, porcelain overcoat and porcelain base.Conducting device comprises bolt electrode, short circuit copper strips, copper electrode, zinc oxide varistor valve and following bolt electrode.Last bolt electrode is fixed on porcelain and puts outward, and following bolt electrode is fixed on the porcelain base.Bolt electrode on one termination of short circuit copper strips, another termination copper electrode.Zinc oxide varistor valve places between copper electrode and the following bolt electrode.Trip gear comprises resistance, dropout electrode, zinc oxide varistor valve, copper electrode, compresses stay cord and dropout spring.Zinc oxide varistor valve places between copper electrode and the dropout electrode, and fixing bucket is fixed on zinc oxide varistor valve, dropout electrode and copper electrode on the porcelain base between following bolt electrode and the porcelain overcoat.One end of copper electrode stretches out fixing bucket, is connected with the zinc oxide varistor valve of conducting device.Resistance R ₁A termination on the bolt electrode, the other end is welded on the dropout electrode; Resistance R ₂A termination copper electrode, the other end also is welded on the dropout electrode.The dropout spring places between the copper electrode of bolt electrode and conducting device.An end that compresses stay cord is welded on the dropout electrode, and the other end is walked around the bolt electrode and is fixed on the porcelain base.The utility model is serially connected between power grid cables and the lightning arrester, when leakage current increases, the heat that produces makes the tin point fusing on the dropout electrode, compressing stay cord unclamps, under dropout spring action of the present utility model, the disconnection that is connected of power grid cables and lightning arrester, thus make lightning arrester avoid thermal explosion.

The utility model can make lightning arrester avoid thermal explosion, thereby has improved the coefficient of safety of electrical network, has brought assurance for the safety in production of electric power system.The utility model has adopted the zinc oxide varistor valve that has identical second peace characteristic with lightning arrester, does not therefore influence the overvoltage protective property of lightning arrester.

Below in conjunction with accompanying drawing the utility model is further described.

Accompanying drawing 1, the utility model structural representation.Wherein, 1-porcelain overcoat, the last bolt electrode of 2-, the 3-nut, 4-bullet pad, the 5-plain cushion, the 6-rubber sheet gasket, the 7-rubber gasket, the 8-bakelite is good for plate, and 9-compresses stay cord, 10-short circuit copper strips, 11-resistance R ₁, the 12-resistance R ₂, 13-copper electrode, the fixing bucket of 14-, 15-dropout electrode, 16-holddown spring, the 17-zinc oxide varistor valve, 18-copper electrode, 19-rubber sheet gasket, 20-plain cushion, 21-bullet pad, the 22-nut, bolt electrode under the 23-, 24-porcelain base, 25-zinc oxide varistor valve, 26-dropout spring.

Accompanying drawing 2, circuit theory diagrams.

Accompanying drawing 3, the work elementary diagram.Wherein, L-power grid cables, TQ-the utility model, MOA-gapless metal-oxide lighting arrester.

Referring to accompanying drawing, last bolt electrode 2 is fixed on the porcelain overcoat 1 by nut 3.The strong plate 8 of bakelite is installed between porcelain outer casing inner wall upper end and last bolt electrode, has groove on the strong plate of bakelite.Bolt electrode 2 on one termination of short circuit copper strips 10, another termination copper electrode 13.Dropout spring 26 is installed between bolt electrode 2 and the copper electrode 13.Following bolt electrode 23 is fixed on the porcelain base 24 by nut 22.Zinc oxide varistor valve 25 is installed between copper electrode 13 and the following bolt electrode 23.Dropout electrode 15, zinc oxide varistor valve 17, holddown spring 16 are placed in the fixing bucket 14 successively, copper electrode 18 inserts fixing bucket between Zinc-oxide piezoresistor 17 and holddown spring 16, in two apertures of the porcelain base 24 under fixing bucket 14 embeds between bolt electrode 23 and the porcelain overcoat 1, copper electrode 18 is positioned at fixing bucket 14 outer ends and is connected with following bolt electrode 23.Resistance R ₁And R ₂Be connected R ₁The other end be welded on the bolt electrode 2 R ₂The other end be welded on the end that copper electrode 18 stretches out fixing bucket 14, A point and dropout electrode 15 weld.An end that compresses stay cord 9 is welded on the dropout electrode 15, and the groove that the other end passes on the strong plate 8 of bakelite is fixed on the little ring of porcelain base 24.

The bolt electrode 2 of going up of the present utility model is connected with power grid cables L, and following bolt electrode 23 is connected with the last bolt electrode of lightning arrester MOA.

Under normal operation operating state, there is not overvoltage in the electrical network, because the effect of lightning arrester MOA, the electric current that flows through among the utility model TQ has only microampere order, at this moment at R ₂The voltage that two ends produce is far smaller than the pressure sensitive voltage of zinc oxide varistor valve 17, and Zinc-oxide piezoresistor 17 and Zinc-oxide piezoresistor 25 all are operated in cut-off region, are in off state.

If electrical network runs into thunderbolt, produce atmospheric over-voltage, at this moment the electric current that flows through among the lightning arrester MOA is very big, because zinc oxide varistor valve 25 has been selected the zinc oxide varistor valve of pacifying characteristic in identical with lightning arrester MOA second for use among the utility model TQ, so through-current capacity can meet the demands fully.At this moment the highest residual voltage at TQ two ends depends on ZnO resistors valve block 25 fully, and it only is worth otherwise the protective value that influences MOA gets final product.Because string has linear resistance R on zinc oxide varistor valve 17 branch roads ₂, and the value of the pressure sensitive voltage of zinc oxide varistor valve 17 is low slightly than ZnO resistors valve block 25, so the electric current that flows through wherein is not too large.R ₁For big resistance linear resistance, because of the restriction of the oxidated zinc varistor valve 17 of the voltage at its two ends, the electric current that wherein flows through is milliampere level just.So, just can satisfy the requirement of thunderbolt state as long as component parameters is chosen suitably.Because the time compole of atmospheric over-voltage is short, the heat that zinc oxide varistor valve 17 produces can not melt the tin point of dropout electrode 15 at all, and all can not threaded off yet.

When if MOA damages owing to aging or other reason cause, it mainly reflects to be exactly the reduction of pressure sensitive voltage and the increase of leakage current, the main cause of MOA blast be exactly among the MOA long period flow through bigger electric current, produce heat, when accumulation of heat will be blasted to a certain degree the time.

When leakage current increases, at R ₂Last generation higher voltage, when its value is higher than the pressure sensitive voltage of zinc oxide varistor valve 17, heat is opened and produced to zinc oxide varistor valve 17, because its time is longer, make the tin point fusing on the dropout electrode 15, compress stay cord and unclamp, under the effect of dropout spring 26, zinc oxide varistor valve 25, following release units such as bolt electrode 23 and porcelain base 24 make the disconnection that is connected of power grid cables and lightning arrester, thereby avoid MOA to cross thermal explosion.

Claims

1. lightning arrester explosion-protection equipment, it is characterized in that it is made of conducting device, trip gear, overcoat and base, conducting device comprises bolt electrode [2], short circuit copper strips [10], copper electrode [13], zinc oxide varistor valve [25] and following bolt electrode [23], last bolt electrode [2] is fixed on the overcoat [1], following bolt electrode [23] is fixed on the base [24], bolt electrode [2] on one termination of short circuit copper strips [10], another termination copper electrode [13], zinc oxide varistor valve [25] place between copper electrode [13] and the following bolt electrode [23]; Trip gear comprises resistance [11,12], dropout electrode [15], zinc oxide varistor valve [17], copper electrode [18], compresses stay cord [9] and dropout spring [26], zinc oxide varistor valve [17] places between copper electrode [18] and the dropout electrode [15], fixing bucket [14] is fixed on dropout electrode [15], zinc oxide varistor valve [17] and copper electrode [18] on the base [24] that is positioned between following bolt electrode [23] and the overcoat [1], one end of copper electrode [18] stretches out fixing bucket [14], be connected resistance R with zinc oxide varistor valve [25] ₁A termination on bolt electrode [2], the other end is welded on the dropout electrode [15], resistance R ₂A termination copper electrode [18], the other end is welded on the dropout electrode [15], dropout spring [26] places between bolt electrode [2] and the copper electrode [13], compresses stay cord [9] one ends and is welded on the dropout electrode [15], and the other end is walked around bolt electrode [2] and is fixed on the base [24].