CN115152109A

CN115152109A - Lightning arrester with protective spark gap

Info

Publication number: CN115152109A
Application number: CN202180013534.6A
Authority: CN
Inventors: G·V·波多金
Original assignee: Streamer Electric Co Inc
Current assignee: Streamer Electric Co Inc
Priority date: 2020-02-07
Filing date: 2021-01-29
Publication date: 2022-10-04
Also published as: WO2021158145A1; RU2735091C1

Abstract

The invention discloses a lightning arrester for electrical equipment or power line elements, comprising a discharge device (arc-extinguishing device), a high-voltage electrode, a low-voltage electrode and an external process spark gap for connecting the arrester to a high-voltage network, as well as a protective gap. A process spark gap is formed between a high-voltage electrode of the lightning arrester and a high-voltage grid electrode. The protective gap is formed between a low-voltage electrode and a high-voltage electrode connected to a low-voltage portion of the arc extinguishing device. The protective gap is formed in such a way that, when the arc extinguishing device is connected to a high-voltage network, its discharge path develops between an electrode point which is the starting point of the development of the discharge and a low-voltage electrode. When the process gap of the electrode gap is triggered, a molten metal point is formed at the end of the electrode, and a conductive plasma cloud is formed in the space near the electrode point, so that favorable conditions are created for breaking down the electrode. It breaks down at a relatively low voltage, significantly lower than the discharge voltage between the cold electrodes of the protective gap of the known design.

Description

Lightning arrester with protective spark gap

Technical Field

The present invention relates to lightning arresters connected to an electric network via a spark discharge gap (hereinafter referred to as "gap") and intended to protect the arrester against unacceptable overvoltages and currents in case of lightning or internal overvoltage in the electric network. The invention also relates to a high voltage transmission line with a lightning arrester provided with a protective gap.

Background

Patent US5663863 (e.g. in figure 11 of the US patent) teaches a lightning arrester comprising a discharge device in the form of a non-linear surge arrester (MOX) which, when an overvoltage occurs on the wire, passes through a process spark gap g between the high voltage electrode of the arrester and the electrode at high voltage ₁ (breakdown thereof by discharge) to the electric wire (see fig. 1 attached to the present specification). The lightning arrester passes through a separate protective gap g between the high-voltage electrode and the low-voltage electrode of the lightning arrester ₂ Protecting the arrester from surges, the protective gap g ₂ Not connected to the process gap g ₁ . When exposed to overvoltage waves, large currents flow through the arrester, the gap g being due to the high non-linearity of the arrester ₂ The voltage across the terminals increases slightly. Only at very high currents, when the arrester loses its non-linear characteristics, the voltage will increase significantly and the gap g will be large ₂ Can be destroyed (see fig. 2 attached to this specification). With this protection method, the possibility of damage of the surge arrester due to current overload is high. Thus, the design described in US5663863 does not have the function of arrester protection.

Disclosure of Invention

The object of the invention is to provide protection against dangerous currents for arresters connected through gaps.

The object of the present invention is solved by a lightning arrester primarily designed for protecting electrical equipment or power lines against overvoltages (e.g. impulse-including lightning). The arrester comprises a discharge device, a high voltage electrode connected to the discharge device and a low voltage electrode connected to the discharge device, the high voltage electrode being arranged to form a process spark gap between the electrodes at high voltage and the ends and/or parts of the high voltage electrode that are closest to each other.

The arrester according to the invention is distinguished in that it comprises a guard electrode which is connected to the low-voltage electrode directly or via a connecting spark gap and which is arranged to form a guard spark gap between the electrode at high voltage and the end of the guard electrode and/or the part closest to each other, wherein the electrical strength of the process spark gap is smaller than the electrical strength of the guard spark gap.

Since the protective spark gap is located just between the protective electrode and the end of the high-voltage electrode of the arrester, which receives the spark discharge connecting the arrester to the electrode at high voltage, or just between the protective electrode and the end of the electrode at high voltage, which is the starting point for the discharge development towards the high-voltage electrode of the arrester, at a voltage at which the discharge device is not broken down, the possibility of spark breakdown of the protective spark gap is provided.

The fact that the dimensions of the process spark gap are smaller than those of the protection spark gap or that the breakdown strength of the process spark gap is smaller than those of the protection spark gap (for example, due to the fact that the radius of curvature of the ends of the electrodes forming the protection spark gap and/or the portions closest to each other is larger compared to similar elements forming the process spark gap) may guarantee that the condition "the electrical strength of the process spark gap must be smaller than that of the protection spark gap" is fulfilled.

The protective gap is preferably formed in such a way that: a discharge path of the guard gap is formed between the electrode site, which is a discharge development starting point when the discharge device is connected to the electrode at a high voltage, and the guard electrode. The discharge devices connected to the grid through the gap may be of different types, for example: lightning arresters, multi-chamber lightning arresters, tubular lightning arresters, valve lightning arresters and the like.

The object of the invention is also solved by a lightning arrester ring made in the form of a chain of lightning arresters connected in series by a spark gap according to any one of the embodiments described above.

The object of the invention is also solved by a transmission line comprising towers, individual insulators and/or insulators assembled in columns or strings, and at least one high voltage line connected directly or by means of fasteners to the individual insulators and/or to the fittings of a first column of insulators or insulator rings, wherein each individual insulator or each column or ring of insulators is fixed to a tower by means of elements of the fittings adjacent to the assigned tower. According to the invention, the transmission line comprises at least one surge arrester according to any of the above options and/or at least one surge arrester ring according to any of the above embodiments. The electrodes at high voltage must be connected to high voltage wires at high voltage.

The invention realizes the technical effect of protecting the discharge equipment from the extreme overvoltage impact, thereby improving the reliability and the service life of the arrester and maintaining the performance of the arrester after being exposed to the extreme overvoltage. All technical results indicated in the present specification, including additions, are achieved simultaneously and in close proximity to each other according to the present invention.

Drawings

FIG. 1 shows a schematic view of a known spark gap in US5663863 with a protective gap;

fig. 2 shows the arrester g of fig. 1 ₂ The operation of the guard gap of (2);

fig. 3 shows a schematic view of a surge arrester with a protective gap according to the invention;

fig. 4 shows an initial stage of operation of the protective gap of the arrester according to fig. 3;

fig. 5 shows a final stage of the operation of the protective gap of the arrester according to fig. 4;

fig. 6 shows a schematic view of an embodiment of a surge arrester with a protection gap according to the invention;

fig. 7 shows an initial stage of the operation of the protective gap of the arrester according to fig. 6;

fig. 8 shows a final stage of operation of the protective gap of the arrester according to fig. 6;

fig. 9 shows a lightning arrester ring according to fig. 3;

fig. 10 illustrates the operation of the protection gap of the arrester string according to fig. 9;

fig. 11 shows an embodiment of a lightning arrester string according to the invention;

fig. 12 illustrates an initial operation of the protection gap of the arrester string of fig. 11;

fig. 13 shows the final operation of the protection gap of the arrester string of fig. 11.

The following elements are shown: 1-a lightning arrester, 2-a conductor, 3-a high-voltage electrode of a main process spark gap, 4-a high-voltage electrode of a lightning arrester, 5-a low-voltage electrode of a lightning arrester, 6-a high-voltage electrode of a lightning arrester protection spark gap, 7-a guard electrode, 8-a spark channel of a process spark gap, 9-a spark channel of a protection spark gap, 10-a combined channel of a protection gap;

the lightning arrester comprises a 11-I section lightning arrester, a 31-I section main process spark gap high-voltage electrode, a 41-I section lightning arrester high-voltage electrode, a 51-I section lightning arrester low-voltage electrode, a 71-I section protection electrode, a 81-I section process spark gap spark channel and a 91-I section protection spark gap high-voltage spark channel;

a 12-II section lightning arrester, a 32-II section main process spark gap high-voltage electrode, a 42-II section lightning arrester high-voltage electrode, a 52-II section lightning arrester low-voltage electrode, a 72-II section protective electrode, a 82-II section process spark gap spark channel, and a 92-II section protective spark gap high-voltage spark channel;

a 13-III section lightning arrester, a 33-III section main process spark gap high-voltage electrode, a 43-III section lightning arrester high-voltage electrode, a 53-III section lightning arrester low-voltage electrode, a 73-III section protective electrode, a 83-III section process spark gap spark channel, and a 93-III section protective spark gap high-voltage spark channel;

u is overvoltage pulse, I is a first section of lightning arrester ring, II is a second section of lightning arrester ring, and III is a third section of lightning arrester ring.

Detailed Description

Hereinafter, the present invention will be described with reference to the drawings and specific embodiments. Such description is given for the purpose of illustrating the invention by way of specific examples and is not intended to limit the scope of protection of the invention as defined by the claims. Also, the features of the description are set forth in the claims to more accurately determine the scope of protection. The present invention is applicable to a variety of discharge devices connected to an electric network through a gap, including but not limited to surge arresters, multi-chamber arresters, tubular arresters, valve arresters, and the like.

The description of the invention is given for the case where the discharge device is at a low voltage and is connected to a high voltage through a process spark gap. However, such a connection does not limit the scope of protection of the invention, but is given only for the purpose of simplifying the description. Generally, the method of connection of the arrester according to the present invention is not specifically defined, and may be varied. The discharge device can be at a high voltage and connected to a low voltage through a process spark gap according to a variation of the connection, which connection option is equivalent to the invention and any other option that implements the operating principle presented in the description.

There are specific embodiments in the drawings and description when forming the process and protecting the spark gap between the ends of the various electrodes. In these cases, the discharge point of the electrode, which is the origin of the discharge arc, is located at the end of the electrode. However, in other embodiments included within the scope of the present invention, the spark gaps may be between portions of the respective electrodes that are closest to each other. In this case, the portions of the electrodes that are closest to each other in the general case may not be the ends of the electrodes (although they may be (e.g., as shown in the drawings)).

In particular, the electrodes may have bends that are positioned closer to each other than the ends of the electrodes (or, in one embodiment, the bends of one electrode may be closer to the ends of the other electrode). In this case, the discharge point of the electrode, which is the origin of the discharge arc, is located at the bent portion, and may migrate as the discharge progresses to the end of the electrode. That is, a discharge arc is initially generated at the bent portions of the electrodes, which are the regions closest to each other, and then moves to the ends of the electrodes as the radius of curvature of the surfaces of the electrodes becomes smaller. All of these embodiments are within the scope of the present invention, and the following description is also applicable to these embodiments, although the present invention is illustrated with an example in which the regions of the electrodes that are closest to each other are the ends of the electrodes.

Fig. 1 shows a schematic view of a known surge arrester (MOX) with a protective gap corresponding to fig. 11 of US566386 patent 3. When an overvoltage occurs on the line 2, the discharge device 1 (which can also be referred to as an arc quenching device, AED) forms a process gap g between the ends of the

electrodes

3 and 4 via the discharge channel 8 ₁ Connected to the lead 2. The AED 1 passes through a protective gap g formed between the ends of the

electrodes

6 and 7 ₂ To prevent overvoltage, and furthermore electrode 6 is connected to electrode 4 on the high side of the AED and electrode 7 is connected to the low voltage electrode of the lightning arrester 5 which is grounded. When triggering the gap g ₁ When an overvoltage wave is applied, a large current flows through the AED 1 (the arrester is in the form of a surge arrester), and the gap g is formed as the resistance of the surge arrester drops sharply during operation ₂ The voltage across the terminals increases slightly.

Fig. 2 shows a protective gap g of the arrester of fig. 1 ₂ The operation of (2). As can be seen from FIG. 2, the gap g ₂ With process gap g ₁ And are not connected in any way. The protective gap is arranged between the individual high voltage electrodes of the protective gap 6 galvanically connected to the high voltage electrode of the arrester 4 and the electrode 7 connected to the low voltage electrode of the arrester 5. Thus, the gap g ₂ Is higher, the voltage thereon is significantly increased, and the gap g ₂ It can only operate at very high current values, whereas the surge arrester loses its non-linear characteristics. With this protection method, the probability of damage of the arrester due to current overload is high, because in the protection gap g ₂ Before operation, the arrester is damaged already by an excessive current load, and therefore the design shown in fig. 1 and 2 does not function to protect the arrester 1.

Another disadvantage of the arrester design according to fig. 1 is that in the process gap g ₁ Has a large short-circuit current and a long duration determined by the switching operation time. This leads to a significant corrosion of the arrester electrode 4.

Fig. 3 shows a schematic view of a surge arrester with a protective gap according to the invention. The arrester has no electrode 6 and participates in forming a process gap g ₁ Lightning arrester of discharge channel 8And a guard electrode 7 directly (galvanically) connected to the low-voltage electrode 5 of the arrester is arranged with a guard gap g between them ₂ 。

Protecting the spark gap g ₂ Formed directly between the end of the high-voltage electrode 4 of the arrester and the guard electrode 7, which receives the spark discharge 8, the spark discharge 8 connecting the arrester to the electrode 3 at high voltage (fig. 3 to 5), or the spark discharge 8 being connected directly between the guard electrode 7 and the end of the electrode 3 at high voltage, which is the starting point of the discharge development of the high-voltage electrode 4 of the arrester (fig. 6 to 8). At a voltage at which the discharge device has not failed, i.e. before an extreme overvoltage is reached that destroys the discharge device, a protective spark gap g is provided ₂ The spark breakdown 9.

In order to first process the spark gap g ₁ In the spark gap g, and then discharge 8 is generated ₂ In which an electric discharge 9 is generated, a process spark gap g ₁ Must be less than the protective spark gap g ₂ The electrical strength of (2). This may be through the process spark gap g ₁ Is smaller than the protective spark gap g ₂ Is ensured, then the gap g ₁ Will be less than the gap g ₂ The breakdown voltage of (c). In another embodiment, this may be through the process spark gap g ₁ Breakdown strength of less than the protective spark gap g ₂ To ensure, for example, due to the gap g ₁ Arranged between rod-like electrodes with a gap g ₂ Between the rod-shaped electrode and a metal sphere (or hemisphere) of larger radius (which provides a more uniform electric field).

Protective gap g ₂ Mainly formed by the following steps: its discharge channel 9 is formed between a certain part of the

electrodes

3 and 4, which is the starting point of the development of the discharge when the discharge device 1 is connected to the electrode 3 at high voltage (and, further, to the high-voltage power network 2), and the guard electrode 7. When the process gap between the electrodes is triggered, a molten metal point is formed at the end of the electrode, and a plasma conductive cloud is formed in the space near the electrode, so that favorable conditions are created for breaking down the electric protection gap. It breaks down at a relatively low voltage, significantly lower than known designs between cold electrodesThe discharge voltage of the protective gap.

The figure shows an embodiment of the invention incorporating an electrode at high voltage. It is represented by

position

3 or 31 depending on the pattern. The electrode may be part of a lightning arrester, which is mounted in connection therewith, or may be an external electrode, so that a process spark gap may be formed between the electrode at high voltage and the end of the high voltage electrode and/or the parts closest to each other.

Since the guard electrode, which is connected to the low-voltage electrode directly or via a connecting spark gap, is mounted so as to make it possible to form a guard spark gap between the ends and/or the portions closest to each other of the guard electrode and the high-voltage electrode or the electrode at high voltage, in order to implement the invention, all three electrodes: the high-voltage electrode, the guard electrode and the electrode at high voltage, or rather their ends and/or the closest parts, should preferably be in line of sight with each other, or in other words in direct proximity to each other in the form of a discharge gap.

With this electrode arrangement, the discharge gaps (process gap and protective gap) are also in line of sight with one another. All this is ensured by the fact that the discharge in the guard gap and the process gap have a common point (discharge point) on one of the electrodes during the guard operation provided by the guard electrodes: a high voltage electrode (e.g., in fig. 3-5) or an electrode at a high voltage (e.g., in fig. 6-8).

To practice the invention, the electrical strength of the process spark gap is less than the electrical strength of the protective spark gap. Variants for ensuring this condition are given in the present description. Since the three electrodes (3, 4 and 7), preferably located in line of sight with each other, participate in the process gap and the protective gap (g, respectively) ₁ And g ₂ ) So there will be one or more spark gaps (

electrodes

3 and 7 in fig. 3) in this design, whose discharge should not be in the process gap g ₁ Before the start of discharge or in the protective gap g ₂ Occurs before the discharge in (1) starts. For this purpose, the dielectric strength of the third spark gap must be greater than that of the process spark gapDielectric strength and dielectric strength to protect the spark gap.

This can be achieved by various methods presented in this specification. This can be ensured, for example, by the distance between the guard electrode and the high-voltage electrode (i.e. the larger dimension of the third spark gap) being larger than the distance between the high-voltage electrode and the electrode at high voltage (i.e. the dimension of the process spark gap) and the distance between the guard electrode and the high-voltage electrode (i.e. the dimension of the guard spark gap).

Fig. 4 shows an initial stage of the operation of the protective gap of the arrester according to fig. 3. Due to the process gap g between the

trigger electrodes

3 and 4 ₁ At the time, a molten metal spot is formed at the end of the electrode 4, and a conductive plasma cloud is formed in the vicinity thereof so as to protect the gap g ₂ The breakdown of (2) creates an advantage. Due to the protective gap g ₂ Near because of the discharge gap g ₁ Thus protecting the gap g by the presence of a plasma cloud formed by the breakdown of ₂ Breakdown at a given relatively low voltage, it provides protection for the discharge device 1 in fig. 1 to 13 before it breaks down and/or exceeds the operating voltage range at extreme over-voltages.

It should be noted that the guard gap g known in the US5663863 patent ₂ In the design of (see fig. 1 and 2), away from the gap g in fig. 1 and 2 ₁ G between the cold electrodes ₂ Is significantly higher than the gap g of the inventive design with different embodiments shown in fig. 3 to 13 ₂ The discharge voltage of (1).

Fig. 5 shows the final stage of the operation of the protective gap of the spark gap according to fig. 3. Process gap g ₁ Channel 8 and protective gap g ₂ The channels 9 merge into one channel 10 between the

electrodes

3 and 7. In this case the electrodes 4 of the arrester do not participate in the flow of short-circuit current and, unlike the arrester of known design according to fig. 1, its corrosion is negligible.

Fig. 6 shows another embodiment of the arrester according to the invention. In this embodiment, too, there is no electrode 6, and the process gap g is involved ₁ Of the discharge channel 8A protective gap g is arranged between the electrode 3 at voltage (grid electrode) and the low-voltage electrode 7 ₂ 。

Fig. 7 shows the operation of the protective gap of the arrester according to fig. 6. Due to the process gap g between the

electrodes

3 and 4 ₁ In operation, a molten metal spot is formed at the end of the electrode 3, and a conductive plasma cloud is formed in the vicinity thereof to protect the gap g ₂ The breakdown creates an advantage. Protective gap g ₂ Breakdown at a given relatively low voltage also provides protection for the arrester 1 before it is destroyed and/or exceeds the operating voltage range.

Fig. 8 shows the final stage of the operation of the protective gap of the arrester according to fig. 6. When triggering the protection gap g ₂ In time, a main current flows through the discharge channel 9 between the

electrodes

3 and 7 and is further grounded. The current through channel 8 is negligible and thus channel 8 is quenched. The electrodes 4 of the arrester do not participate in the flow of short-circuit current and, unlike the arrester of known design according to fig. 1, its corrosion is negligible.

Fig. 9 shows a lightning arrester string according to the invention. The

discharge devices

11, 12, 13 included in the ring are connected to the wire 2 and pass through the process spark gap g ₁ Are connected to each other, the

discharge channels

81, 82, 83. The

discharge devices

11, 12, 13 of successive segments I, II, III are fixed to an insulating structure (not shown in fig. 9 and 10). The arrester ring passes through a first technological gap g ₁ Is connected to the conductive line, the first process gap g ₁ Formed between the high voltage electrode 31 mounted on the wire and the high voltage electrode 41 of the first arrester. The second arrester is connected to the high-voltage electrode 42 of the second spark gap via a gap g formed between the low-voltage electrode 51 of the first arrester (directly, galvanically) connected to the high-voltage electrode 32 of the gap of the second arrester) and the high-voltage electrode 42 of the second arrester ₁ Are connected to the channel 82. Similarly, a third and subsequent surge arrester is connected. The low voltage electrode of the last arrester (in the three arrester ring embodiment shown in fig. 7, this is electrode 53) is grounded.

Each spark gap is connected directly (galvanically) to a corresponding low voltage at a corresponding

high voltage electrode

41, 42, 43 and

directlyThe guard electrodes

71, 72, 73 of the

poles

51, 52, 53 have their own guard gap g between them ₂ 。

Fig. 10 shows the operation of the protective gap of the arrester garland according to fig. 9 at unacceptably high currents of the arrester, but still before an extreme overvoltage that damages the discharge device is reached. In this case, the current flows from the wire 2 through the electrode 31, the passage 81, the passage 91, the electrode 71, the electrode 51 to the electrode 32, the passage 82, the passage 92, the electrode 72, the electrode 52 to the electrode 33, the passage 83, the passage 93, the electrode 73, and the electrode 53 bypassing the

discharge devices

11, 12, and 13. The

discharge devices

11, 12 and 13 are thus protected from impermissible currents and extreme overvoltages.

Fig. 11 shows an embodiment of a lightning arrester ring according to the invention. Each arrester in the ring (except for the last one grounded) has two protective gaps g ₂ . One formed between the corresponding

high voltage electrode

41, 42, 43 and the upper end of the

electrode

71, 72, 73 and a second formed between the lower end of the

corresponding guard electrode

71, 72, 73 and the

low voltage electrode

51, 52, 53 of the

arrester

11, 12, 13 and is in fact the connecting spark gap of the guard electrode. The

arresters

11, 12, 13 are fixed to the insulating structure (not shown in figures 9, 10 and 11).

Fig. 12 shows the protective gap g of the arrester ring of fig. 11 ₂ The initial operation of (1). In this case, a current of a high value that is unacceptable for the arrester flows from the conductor 2 past the

arrester

11, 12 and 13 through the electrode 31, the passage 81, the passage of the upper protective gap 91, the electrode 71, the passage of the lower protective gap 101, the passage 82 of the process gap, the passage of the upper protective gap of the second arrester 92, the electrode 72, the passage of the lower protective gap 102, the passage of the process gap 83, the passage of the upper protective gap of the second spark gap 93, the electrode 73 and the electrode 53.

Fig. 13 shows the final operation of the protective gap of the arrester ring of fig. 12. After the guard gap operation as shown in fig. 12, the arc paths merge. The channel 81 and the channel 91 are merged into a single channel 111. The channel 101, the channel 82 and the channel 92 are combined into a single channel 112. The channel 102, the channel 83 and the channel 93 are combined into a single channel 113. Furthermore, these single arc-shaped

channels

111, 112, 113 are detached from the

electrodes

41, 42, 43, 51 and 52 of the arrester ring. In this case, a current of a high value that is not acceptable for the surge arrester flows from the wire 2 through the electrode 31, the passage 111, the electrode 71, the passage 112, the electrode 72, the passage 113, the electrode 73, and the electrode 53 outside the

surge arresters

11, 12, and 13. In this case, the

arresters

11, 12 and 13 are protected from unacceptable currents and the

electrodes

41, 42, 43, 51 and 52 of the

arresters

11, 12 and 13 are virtually free from corrosion.

The surge arrester and surge arrester ring shown in fig. 3-13 and described in this section can be used for transmission lines comprising towers, individual insulators and/or insulators assembled into columns or rings, and at least one high voltage line connected to an accessory of an individual insulator and/or to a first column insulator or insulator ring, either directly or via a fastening device. Each individual insulator or each insulator column or ring is secured to one of the towers by an element of the fitting adjacent to the designated tower. According to the invention, the power line may comprise at least one arrester according to any of the above embodiments and/or at least one arrester ring according to any of the above embodiments. The electrode at high voltage must be connected to the wire at high voltage.

The embodiments shown in the drawings and described in detail in the specification are intended to facilitate an understanding of the invention and should not be construed to limit the scope of the invention, which is defined by the appended claims. The described embodiments may be combined and combined, including additional, in any combination that ensures implementation of the principles of operation and implementation of the technical result. Additional technical results may be achieved as a result of combinations of the individual embodiments.

Claims

1. An arrester comprising a discharge device, a high-voltage electrode connected to the discharge device and a low-voltage electrode connected to the discharge device, the high-voltage electrode being arranged to form a process spark gap between an electrode at high voltage and an end portion and/or a portion closest to each other of the high-voltage electrode, characterized in that the arrester comprises a guard electrode which is connected to the low-voltage electrode directly or via a connecting spark gap and which is arranged to form a guard spark gap between an electrode at high voltage and an end portion and/or a portion closest to each other of the guard electrode, wherein the electrical strength of the process spark gap is smaller than the electrical strength of the guard spark gap.

2. The surge arrester of claim 1 wherein the process spark gap is smaller in size than the protection spark gap.

3. The surge arrester of claim 1 wherein a breakdown voltage of the process spark gap is less than a breakdown voltage of the protection spark gap.

4. The surge arrester of claim 1 wherein the protective gap is formed by: a discharge path of the guard gap is formed between the electrode site, which is a discharge development starting point when the discharge device is connected to the electrode under high voltage, and the guard electrode.

5. The surge arrester of claim 1 wherein the discharge device is a surge arrester, a multi-chamber arrester, a tubular arrester, or a valve arrester.

6. An arrester ring, characterized in that it is made in the form of a chain of arresters according to any one of claims 1-5 connected in series by a spark air gap.

7. Transmission line comprising a plurality of towers, individual insulators and/or insulators assembled in columns or rings, and at least one high voltage electric line connected directly or by means of fasteners to the individual insulators and/or the first column of insulators or insulator rings, each individual insulator or each column or ring of insulators being fixed to a tower by means of elements of said fittings adjacent to the specific tower, characterised in that it comprises at least one arrester according to any of claims 1-5 and/or at least one arrester ring according to claim 6, wherein the electrodes at high voltage are connected to the electric line at high voltage.