An arc extinguishing structure and arc extinguishing method capable of reducing arc extinguishing gas triggering time

Abstract

The application discloses an arc extinguishing structure capable of reducing arc extinguishing gas trigger time, which comprises a high-voltage side electrode, a lightning rod electrode, a first Rogowski coil, a second Rogowski coil, an arc extinguishing tube and a plurality of parallelly installed pole towers, and an arc extinguishing method is as follows: when a lightning strikes the pole tower, the first Rogowski coil is used to induce lightning current on the pole tower and output a first induced current, the thermal effect of the first induced current is used to preheat a gas pill, so that the internal temperature of the gas pill in the arc extinguishing tube is increased; when the lightning strikes a high-voltage transmission line, the second Rogowski coil is used to induce arc on the pole tower and output a second induced current, the second induced current triggers the preheated gas pill in the arc extinguishing tube, so that the gas pill is exploded in advance by high-temperature arc impact, high-speed airflow is generated in the explosion moment and sprayed out from the upper end of the arc extinguishing tube to act on the residual arc, so that the arc extinguishing time is shortened. The application can trigger the gas pill more quickly, so that the arc extinguishing time is reduced, and the arc extinguishing time is shortened.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of lightning protection and arc extinguishing, and particularly relates to an arc extinguishing structure and an arc extinguishing method capable of reducing arc extinguishing gas trigger time. BACKGROUND

[0002] Lightning protection of power transmission lines has always been an important content of lightning protection work of the power department, and lightning fault is still one of the important factors affecting the safety of power grids. Lightning can cause different forms of damage and destruction to power facilities, and cloud discharge in power systems can cause lightning overvoltage. Lightning overvoltage can cause damage to insulators and power transmission lines. When lightning strikes the power transmission line, the impulse flashover caused by the lightning strike can cause the line insulator to flashover, and then a large power frequency current flow is generated, which can damage the insulator string and fittings, cause line accidents, and the lightning striking the power transmission line or the lightning conductor can cause strand breakage or even breakage, which can prevent power transmission work. In view of this, the power department generally installs a line lightning protection device on the power transmission line to achieve protection. The existing lightning protection and arc extinguishing device can make the voltage-second characteristic of the active arc extinguishing parallel gap more flat, but the existing lightning protection and arc extinguishing device can only reduce the wave front steepness of the lightning current, and cannot further attenuate the amplitude of the lightning current, and the attenuation capacity of the lightning current is limited. Since the generation of the upward leader of the traditional lightning rod needs to go through a delay time, this delay time will limit the timeliness of the vertical or horizontal lightning conductor, resulting in low sensitivity of the gas arc extinguishing mode to small current reaction, and in high soil resistivity areas or areas limited by terrain, it is often difficult to meet the requirement of reducing resistance. In view of the above problems, an arc extinguishing method capable of reducing arc extinguishing gas trigger time is proposed, which aims to improve the reliability of the new lightning protection and arc extinguishing device for insulator protection. SUMMARY

[0003] The application aims to provide an arc extinguishing structure and an arc extinguishing method capable of reducing arc extinguishing gas trigger time, and aims to improve the lightning protection level of the region, which can attenuate the amplitude of the lightning current and avoid damage to the power transmission line caused by the too large amplitude of the instantaneous lightning current. Due to the preheating effect of the gas pellet, the gas pellet can be triggered more quickly, so that the arc extinguishing time is reduced, thereby shortening the arc extinguishing time. In order to achieve the above purpose, the application adopts the following technical solutions:

[0004] According to one aspect of the present application, there is provided an arc extinguishing structure capable of reducing arc extinguishing gas trigger time, the arc extinguishing structure comprising a high-voltage side electrode, a lightning rod electrode, a first Rogowski coil, a second Rogowski coil, an arc extinguishing tube, a plurality of parallelly installed tower poles, insulators for supporting high-voltage transmission lines being arranged on the tower poles, a plurality of air pellets being sealed and distributed in the arc extinguishing tube, the first Rogowski coil and the second Rogowski coil being respectively parallelly sleeved on two different tower poles, the output side of the first Rogowski coil and the output side of the second Rogowski coil being respectively connected to the air pellets through wires, one side of the lightning rod electrode being embedded on the side of the arc extinguishing tube, the other side of the lightning rod electrode being connected to the tower pole on which the second Rogowski coil is sleeved, one end of the high-voltage side electrode being directed towards the high-voltage transmission line at the insulator, and the other end of the high-voltage side electrode being directed towards the lightning rod electrode.

[0005] Further preferably, the above-mentioned scheme has a capacitor connected in parallel between the wires on the output side of the first Rogowski coil.

[0006] Further preferably, the above-mentioned scheme has an air gap between the other end of the high-voltage side electrode and the lightning rod electrode.

[0007] Further preferably, the above-mentioned scheme has the arc extinguishing tube being closed at the bottom and open at the upper end, the air pellets being distributed in the upper end portion inside the arc extinguishing tube, the air pellets and the bottom of the arc extinguishing tube having a sealed cavity therebetween, and one side of the lightning rod electrode being embedded on the side wall of the cavity.

[0008] Further preferably, the above-mentioned scheme has the lightning rod electrode extending into the cavity or not extending into the cavity.

[0009] According to another aspect of the present application, there is provided an arc extinguishing method capable of reducing arc extinguishing gas trigger time, the arc extinguishing method comprising the following steps: when a lightning strikes a tower pole, a first Rogowski coil is used to induce lightning current on the tower pole and output a first induced current, and the first induced current is used to preheat air pellets by thermal effect, so that the temperature inside the air pellets in the arc extinguishing tube is increased; when a lightning strikes a high-voltage transmission line, a second Rogowski coil is used to induce arc on the tower pole and output a second induced current, and the second induced current triggers the preheated air pellets in the arc extinguishing tube, so that the air pellets are exploded in advance by high-temperature arc impact, and high-speed airflow is generated at the moment of explosion and sprayed out from the upper end of the arc extinguishing tube to act on residual arc, thereby shortening the time for completely extinguishing the arc.

[0010] Further preferably, the above-mentioned scheme has the arc occurring flashover on the insulator when a lightning strikes a high-voltage transmission line, and the arc back strike breaks through the air gap on the high-voltage side electrode; after the arc back strike breaks through the air gap, the arc is guided through the lightning rod electrode and the tower pole, and the second Rogowski coil is used to induce the arc on the tower pole and output the second induced current.

[0011] Preheating the gas pellet by using the thermal effect of the first induced current, so that the internal temperature of the gas pellet in the arc extinguishing tube is less than half of the temperature when triggered.

[0012] In summary, due to the adoption of the technical scheme, the present application has the following technical effects:

[0013] After the lightning breakdown gap, due to the preheating effect of the coil on the gas pellet, the gas pellet can be triggered more quickly, so that the arc extinguishing time is reduced, thereby shortening the arc extinguishing time, and effectively solving the problem of low sensitivity caused by the gas arc extinguishing method when extinguishing small arcs; the lightning electrode is connected with the arc rod of the tower, the arc rod of the tower passes through the center of the second Rogowski coil, the second Rogowski coil is connected with the arc extinguishing tube through the electric wire to form a secondary circuit, the current of the arc flows in the secondary circuit of the second Rogowski coil to generate an induced current, the induced current will trigger the gas pellet built-in the arc extinguishing tube to generate high-speed high-pressure gas; the generated high-speed high-pressure gas acts on the residual arc, at this time, the arc is reduced in energy after the recoil effect, the arc extinguishing difficulty is reduced, and the gas at this time is easy to destroy the arc channel, thereby extinguishing the arc. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 Fig. 1 is a schematic diagram of an arc extinguishing structure capable of reducing the triggering time of arc extinguishing gas according to the present application;

[0015] Figure 2 Fig. 2 is a response time diagram of the gas pellet explosion gas according to the present application;

[0016] In the drawings, 1 is a high-voltage transmission line, 2 is an insulator, 3 is a high-voltage electrode, 4 is a gas pellet, 5 is a lightning electrode, 6 is a first Rogowski coil, 7 is a second Rogowski coil, 8 is a tower, 9 is an air gap, 10 is an arc extinguishing tube, 11 is a capacitor, and 40 is a cavity. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical scheme and advantages of the present application more clear and explicit, the following preferred embodiments are described with reference to the drawings. However, it should be noted that many details in the description are only to make the reader have a thorough understanding of one or more aspects of the present application, and the aspects of the present application can be realized without these specific details.

[0018] As Figure 1As shown, according to the arc extinguishing structure capable of reducing arc extinguishing gas trigger time provided by the application, the arc extinguishing structure comprises a high-voltage side electrode 3, a lightning rod electrode 5, a first Rogowski coil 6, a second Rogowski coil 7, an arc extinguishing tube 10, and a plurality of parallelly installed tower poles 8, the tower poles 8 are provided with insulators 2 for supporting the high-voltage transmission line 1, a plurality of air pellets 4 are sealed and distributed in the arc extinguishing tube 10, the first Rogowski coil 6 and the second Rogowski coil 7 are respectively and parallelly sleeved on two different tower poles 8, the output side of the first Rogowski coil 6 and the output side of the second Rogowski coil 7 are respectively connected to the air pellets 4 through wires, one side of the lightning rod electrode 5 is embedded on the side of the arc extinguishing tube 10, the other side of the lightning rod electrode 5 is connected to the tower pole 8 on which the second Rogowski coil 7 is sleeved, one end of the high-voltage side electrode 3 points to the high-voltage transmission line 1 at the insulator 2, the other end of the high-voltage side electrode 3 points to the lightning rod electrode 5, and the other end of the high-voltage side electrode 3 has an air gap 9 with the lightning rod electrode 5, in the application, two Rogowski coils are connected in parallel structure on the air pellets, and the preheating process of the air pellets by the ground lightning current is realized, due to the existence of the preheating process, when the lightning current breaks the gap, the air pellets can reach the trigger temperature threshold faster than in the case without heating, thereby realizing the purpose of reducing the arc extinguishing gas trigger time.

[0019] In the embodiment of the application, as shown in the figure, Figure 1 A capacitor 12 is connected in parallel between the wires at the output side of the first Rogowski coil 6, by selecting the appropriate size of the capacitor, the size of the induced current is ensured to be insufficient to trigger the air pellet 4, at this time, the air gap in the arc extinguishing tube 10 is not broken down in the preheating process; after lightning strikes the tower pole, the induced current in the first Rogowski coil 6 can preheat the air pellet 4, and due to the parallel connection of the capacitor 12, part of the energy is absorbed, limiting the voltage across the air pellet 12 from triggering the air pellet, so that the arc extinguishing time is advanced.

[0020] In the embodiment of the application, as shown in the figure, Figure 1 The bottom of the arc extinguishing tube 10 is closed and the upper end is open, the air pellets 4 are distributed in the upper end portion of the arc extinguishing tube 10, the air pellets 4 and the bottom of the arc extinguishing tube 10 have a cavity 40, one side of the lightning rod electrode 5 is embedded in the side wall of the cavity 40, and the cavity 40 can absorb part of the heat in the preheating process, so that the air pellets in the arc extinguishing tube 10 are not too high in temperature in the preheating process.

[0021] In the application, the arc extinguishing process of the arc extinguishing structure of the application is further described:

[0022] 1) Lightning rod tower produces induced current: when lightning occurs, lightning strikes the tower, lightning current flows through the tower into the ground, and the first Rogowski coil induces current, which plays a role in preheating the air pellet 4. Since the capacitor 11 is connected in parallel with the first Rogowski coil, by selecting the appropriate size of the capacitor, the size of the induced current is ensured to be insufficient to trigger the air pellet, and at this time the air gap is not broken down during the preheating process.

[0023] 2) Parallel connection between two Rogowski coils: Rogowski coil is a reactive magnetic field, and the output is a high-frequency pulse. The Rogowski coil is high impedance and does not participate in the discharge of lightning current. The output current generated by the Rogowski coil is added to the air pellet resistance, producing a thermal effect that advances the gas release time.

[0024] 3) Arc-triggered arc-extinguishing air pellet: When lightning strikes the transmission line, the arc back strikes the tower, and at this time the second Rogowski coil generates an induced current that will trigger the action of the built-in arc-extinguishing air pellet to produce high-speed high-pressure gas. Then, the high-speed high-pressure gas produced acts on the residual arc, and at this time the arc is greatly reduced in energy after the recoil effect, and the arc-extinguishing difficulty is greatly reduced. At this time, the gas is extremely easy to destroy the arc channel, thereby extinguishing the arc.

[0025] According to another aspect of the present application, as Figure 1 shown, the present application provides an arc-extinguishing method capable of reducing the triggering time of arc-extinguishing gas, which includes the following methods: when lightning strikes the tower 8, the first Rogowski coil 6 is used to induce the lightning current on the tower 8 and output the first induced current. The thermal effect of the first induced current preheats the air pellet 4 in the arc-extinguishing tube 10, causing the internal temperature of the air pellet 4 to rise. When lightning strikes the high-voltage transmission line 1, the arc occurs on the insulator 2 to produce lightning current, and the arc back strikes the air gap 9 on the high-voltage side electrode 3. After the arc back strikes the air gap 9 between the high-voltage side electrode 3 and the lightning rod electrode 5, the arc back strikes the air gap 9 between the high-voltage side electrode 3 and the lightning rod electrode 5, and the second Rogowski coil 7 is used to induce the arc on the tower 8 and output the second induced current. The second induced current triggers the air pellet 4 built into the arc-extinguishing tube 10, causing the air pellet 21 to be impacted by the high-temperature arc and explode in advance. The high-temperature arc impact generates high-pressure gas, and a high-speed airflow is instantly generated from the upper end of the arc-extinguishing tube 10 and acts on the residual arc, thereby extinguishing the arc. The air pellet 4 (gas generating material) in the arc-extinguishing tube 10 is impacted and exploded by the high-temperature arc, rapidly heated to generate high-pressure gas, and a high-speed airflow is instantly generated and sprayed out of the arc-extinguishing tube 10. The high-speed airflow sprayed out blows the arc and extinguishes the residual arc, achieving reliable arc interruption.

[0026] In the embodiment of the present application, the hot effect of the first induced current is used to preheat the gas pellet 4, so that the internal temperature of the gas pellet 4 in the arc extinguishing tube 10 is less than half to four-fifths of the temperature when triggered, and the preheating of the hot gas pellet 4 is carried out in a critical condition of being triggered to explode, and the voltage at both ends of the gas pellet is limited so as not to trigger the gas pellet. When the arc back strike breaks the air gap 9 between the high-voltage electrode 3 and the lightning electrode 5, the arc is introduced into the tower 8 for release, and the second induced current triggers the gas pellet 4 built in the arc extinguishing tube 10 without further preheating, and the gas pellet 4 is triggered to explode instantaneously. The high-pressure gas generated after the explosion of the gas pellet 4 blows out the residual arc to extinguish the arc, so that the arc extinguishing time is advanced.

[0027] In the present application, as shown in the figure, Figure 2 When the tower is struck by lightning, the first Rogowski coil 6 induces an output current by lightning current, and the hot effect of the output current is used to heat the gas pellet 4, so that the internal temperature of the gas pellet 4 is increased. When the transmission line is struck by lightning, the second Rogowski coil 7 induces an output current by lightning back strike breaking the air gap, and the induced current output by the second Rogowski coil 7 triggers the gas pellet 4 to test the explosion gas flow response time (after triggering, it is considered), CH1 represents the triggering pulse, and the mutation point of CH2 is the moment when the high-speed gas flow is generated. After the tower is struck by lightning, the induced current exists in the first Rogowski coil 6, which can preheat the gas pellet 4, and due to the parallel action of the capacitor 11, the voltage at both ends of the gas pellet is limited so as not to trigger the gas pellet, so that the arc extinguishing time is advanced. When the transmission line is struck by lightning, the arc extinguishing structure works, so it can be seen that the time interval from the generation of the triggering pulse to the moment of the gas flow generation is about 0.2 ms. The triggering of the gas pellet 4 has a voltage threshold. Due to the advance of the arc extinguishing time, the triggering voltage waveform of the gas pellet 4 is CH2', which can make the gas pellet trigger faster at the moment of zero voltage, shorten the triggering time, and greatly shorten the arc extinguishing time. The present application can extinguish the arc in the small current stage, improve the arc extinguishing efficiency, and the internal instantaneous current value is small, which will not cause system overvoltage.

[0028] The above only describes the preferred embodiments of the present application, and it should be noted that those skilled in the art can make some improvements and refinements without departing from the principles of the present application, and these improvements and refinements should also be considered as the protection scope of the present application.

Claims

1. An arc extinguishing method capable of reducing the triggering time of the arc-extinguishing gas, the arc extinguishing method comprising an arc extinguishing structure capable of reducing the triggering time of the arc-extinguishing gas, characterized in that: The arc-extinguishing structure includes a high-voltage side electrode (3), a lightning electrode (5), a first Rogowski coil (6), a second Rogowski coil (7), an arc-extinguishing tube (10), and multiple parallel-installed towers (8). Insulators (2) for supporting the high-voltage transmission line (1) are installed on the towers (8). Gas pellets (4) are sealed inside the arc-extinguishing tube (10). The first Rogowski coil (6) and the second Rogowski coil (7) are respectively mounted in parallel on two different towers (8). The output side of the first Rogowski coil (6) and the second Rogowski coil (7) are connected. The output side of the coil (7) is connected to the air pellet (4) via wires. One side of the lightning electrode (5) is embedded in the side of the arc-extinguishing tube (10). The other side of the lightning electrode (5) is connected to the tower (8) on which the second Rogowski coil (7) is mounted. One end of the high-voltage side electrode (3) points to the high-voltage transmission line (1) at the insulator (2), and the other end of the high-voltage side electrode (3) points to the lightning electrode (5). There is an air gap (9) between the other end of the high-voltage side electrode (3) and the lightning electrode (5). The arc extinguishing method includes the following steps: When lightning strikes a tower, the first Rogowski coil (6) induces the lightning current on the tower (8) and outputs a first induced current. The heat effect of the first induced current is used to preheat the gas pellet (4), so that the internal temperature of the gas pellet (4) in the arc extinguishing tube (10) increases. When lightning strikes a high-voltage transmission line (1), the second Rogowski coil (7) induces the arc on the tower (8) and outputs a second induced current. The second induced current triggers the preheated gas pellet (4) placed in the arc extinguishing tube (10), so that the gas pellet (21) is impacted by the high-temperature arc and explodes prematurely. At the moment of explosion, a high-speed airflow is generated and sprayed out from the upper end of the arc extinguishing tube (10) to act on the residual arc, thereby shortening the time for the arc to be completely extinguished.

2. The arc extinguishing method according to claim 1, which can reduce the triggering time of the arc-extinguishing gas, is characterized in that: A capacitor (11) is connected in parallel between the wires on the output side of the first Rogowski coil (6).

3. The arc extinguishing method according to claim 1, which can reduce the triggering time of the arc-extinguishing gas, is characterized in that: The bottom of the arc-extinguishing tube (10) is closed and the top is open. The gas pellet (4) is distributed in the upper part of the arc-extinguishing tube (10). There is a sealed cavity (40) between the gas pellet (4) and the bottom of the arc-extinguishing tube (10). The side of the lightning electrode (5) is embedded in the side wall of the cavity (40).

4. The arc extinguishing method according to claim 3, which can reduce the triggering time of the arc-extinguishing gas, is characterized in that: The lightning electrode (5) may or may not extend into the cavity (40).

5. An arc extinguishing method according to claim 1 that can reduce the triggering time of the arc-extinguishing gas, characterized in that: When lightning strikes the high-voltage transmission line (1), it causes the arc to flash over on the insulator (2) and generate a lightning current. The arc counter-current is introduced into the high-voltage side electrode (3) to break down the air gap (9). After the arc counter-current breaks down the air gap (9), it passes through the lightning electrode (5) and the tower (8). The second Rogowski coil (7) is used to induce the arc on the tower (8) and output the second induced current.

6. The arc extinguishing method according to claim 1, which can reduce the triggering time of the arc-extinguishing gas, is characterized in that: When the gas pellet (4) is preheated using the thermal effect of the first induced current, the internal temperature of the gas pellet (4) in the arc extinguishing tube (10) is less than half the temperature when it is triggered.

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