Lightning arrester connected in series with air-blast arc extinguishing gap

Abstract

The utility model provides a lightning arrester connected in series with air-blast arc extinguishing gaps, which comprises a zinc oxide body, a middle gap is arranged on the zinc oxide body, and a closed-loop electrode is arranged on the middle gap; the middle gap is connected with an air-blast arc extinguishing assembly, the air-blast arc extinguishing assembly is connected with a threaded electrode, and the threaded electrode is connected with a high-voltage line; the air-blowing arc extinguishing assembly comprises a connecting column, a threaded electrode is connected to the connecting column, and a middle gap is connected below the connecting column; a plurality of compression pipelines are installed in the connecting column, the compression pipelines are connected end to end and installed in the connecting column in an inclined mode, arc blowing openings are formed in the positions, corresponding to the end-to-end connection positions of the compression pipelines, of the outer wall of the connecting column, and the arc blowing openings communicate with the compression pipelines; and an arc striking table is arranged in the compression pipeline. According to the lightning arrester provided by the utility model, airflow is generated at the arc blowing port through the air-blowing arc extinguishing assembly and acts on an electric arc outside the arc blowing port, and the electric arc outside the arc blowing port is gradually lengthened under the action of the airflow, so that the effect of extinguishing the electric arc is achieved, and stable operation of an electric power system is ensured.

Description

Technical Field

[0001] This utility model belongs to the field of power system line lightning protection technology, specifically to a surge arrester with a series air blowout arc extinguishing gap. Background Technology

[0002] With societal progress and improved living standards, the use of smart home appliances has led to a greater demand for electricity, resulting in a surge in the scale of power transmission lines. Power transmission lines are the largest man-made lightning conductors on the ground, and lightning-induced power outages are one of the most serious safety hazards to the power grid. The damage to power transmission lines caused by lightning strikes manifests primarily as thermal, mechanical, and electrical effects. Through long-term experience in power transmission line layout, selecting appropriate overhead conductor cross-sectional dimensions and using reasonable wiring methods can prevent damage to the transmission lines caused by the thermal and mechanical effects of lightning current. However, changing the wiring method and the cross-sectional dimensions of the overhead conductors cannot prevent the overvoltage electrical effect caused by lightning strikes. When the lightning overvoltage exceeds the insulation withstand voltage level of the transmission line, insulation breakdown will occur between the conductor and the ground wire or tower. Subsequently, the power frequency voltage will continue to discharge through the flashover channel, forming a power frequency arc, which will cause the line to trip and malfunction.

[0003] Currently, domestic lightning protection measures mainly involve using porcelain crossarms, adding line surge arresters, and reducing tower grounding resistance to prevent flashover of tower insulators during lightning strikes. Among these, installing line surge arresters can effectively reduce the risk of insulator flashover during lightning strikes. These arresters utilize the nonlinear characteristics of zinc oxide varistors to release lightning energy, thereby suppressing power frequency follow current and preventing insulation flashover and conductor breakage. However, these line surge arresters bear power frequency voltage for extended periods, making them prone to aging and affecting the protection of transmission lines. Therefore, transmission lines often use series gap surge arresters (EGLAs). EGLAs consist of the arrester body and a gap connected in series. This structure ensures that the arrester body only bears power frequency voltage during gap discharge; under operating voltage, the voltage borne by the body is very small, and the varistors do not deteriorate. Compared to gapless surge arresters, EGLAs have advantages such as simple structure, low maintenance workload, and long lifespan, and are widely used. However, during the use of series gap surge arresters, relying solely on the nonlinear characteristics of the zinc oxide body of the surge arrester is sometimes insufficient to quickly extinguish the power frequency arc, affecting the stable operation of the power system and potentially causing line tripping and power outages. Utility Model Content

[0004] To address the problem that existing series gap surge arresters sometimes struggle to quickly extinguish power frequency arcs by relying solely on the nonlinear characteristics of the zinc oxide body of the arrester, this invention provides a surge arrester with a series air-blown arc-extinguishing gap.

[0005] To achieve the above objectives, this utility model provides the following technical solution:

[0006] This utility model proposes a surge arrester with a series gas blowout arc extinguishing gap, including a zinc oxide body, an intermediate gap installed on the zinc oxide body, and closed-loop electrodes installed on both ends of the intermediate gap respectively.

[0007] An air-blown arc extinguishing assembly is connected above the intermediate gap, and a threaded electrode is connected above the air-blown arc extinguishing assembly. The threaded electrode is connected to a high-voltage line.

[0008] The air-blowing arc extinguishing assembly includes a connecting column, with the threaded electrode connected to the top of the connecting column and the intermediate gap connected to the bottom of the connecting column; multiple compression pipes are installed inside the connecting column, with the multiple compression pipes connected end to end and installed at an angle inside the connecting column; an arc-blowing port is provided on the outer wall of the connecting column at the position where the compression pipes are connected end to end, and the arc-blowing port is connected to the compression pipe.

[0009] An arc-starting platform is installed inside the compression pipe.

[0010] Preferably, the inner wall of the compression pipe is coated with a high-density polyethylene coating.

[0011] Preferably, an annular arc-starting electrode is provided at the port of the compression pipe.

[0012] Preferably, the connecting column is a columnar structure.

[0013] Preferably, a skirt is provided on the outer wall of the connecting column between the blow-off ports.

[0014] Preferably, the skirt has a spiral structure.

[0015] Preferably, multiple arc-initiating platforms are provided, and the multiple arc-initiating platforms are distributed alternately at equal intervals within the compression pipe.

[0016] Preferably, the arc-starting platform is a copper nail.

[0017] Preferably, a parallel capacitor is connected in parallel across both ends of the zinc oxide body.

[0018] Preferably, the length of the threaded electrode is 10-15 cm.

[0019] Compared with the prior art, the present invention has the following beneficial technical effects:

[0020] This invention proposes a surge arrester with a series air-blown arc-extinguishing gap. Multiple end-to-end, inclined compression pipes in the air-blown arc-extinguishing assembly form a breakdown channel, guiding the arc to flow along a specific path within the connecting column. This causes the arc within the breakdown channel to generate temperature and pressure gradients with the arc outside the channel under mechanical compression and the arc's own self-magnetic compression. This results in airflow at the arc-blowing opening, which in turn acts on the arc outside the opening. Under the influence of this airflow, the arc outside the opening gradually elongates, ultimately extinguishing the arc. Then, two closed-loop electrodes further extinguish the arc, rapidly extinguishing the power frequency arc, ensuring the stable operation of the power system, and preventing line tripping and power outages.

[0021] Furthermore, this utility model proposes a surge arrester with a series air-blown arc-extinguishing gap, in which a high-density polyethylene coating is provided on the inner wall of the compression pipe. The high-density polyethylene coating improves the ablation resistance of the compression pipe and extends its service life.

[0022] Furthermore, this utility model proposes a surge arrester with a series air-blown arc-extinguishing gap, in which an annular arc-initiating electrode is installed at the port of the compression pipe. This effectively guides the arc into the compression pipe, ensuring that the arc flows along a preset path. This improves the guidance and controllability of the arc, helps to enhance the arc-extinguishing effect of the air-blown arc-extinguishing assembly, and enables the surge arrester to extinguish the arc more quickly and reliably during lightning strikes or short-circuit faults, thus protecting the safe and stable operation of the power system.

[0023] Furthermore, this utility model proposes a surge arrester with a series air-blown arc extinguishing gap, in which a skirt is provided on the outer wall of the connecting column between the arc extinguishing ports. The skirt has a spiral structure to prevent the arcs outside the two arc extinguishing ports from connecting, blocking the potential path of the arc, ensuring effective control and rapid extinguishing of the arc within the air-blown arc extinguishing assembly, and improving the safety performance and arc extinguishing efficiency of the surge arrester.

[0024] Furthermore, this utility model proposes a surge arrester with series air-blown arc-extinguishing gaps, which has multiple arc-initiating platforms installed inside the compression pipe. When struck by lightning, multiple gaps can be broken down, effectively guiding the lightning impact arc to flow along a predetermined path, enhancing the arc's guidance, improving the arc's dispersion and cooling efficiency within the pipe, and accelerating the arc's extinguishing process.

[0025] Furthermore, this invention proposes a surge arrester with a series air-blown arc-extinguishing gap, in which parallel capacitors are connected in parallel across both ends of the zinc oxide body, providing a low-impedance path for high-frequency lightning overvoltages, enabling lightning to discharge rapidly to the ground. Attached Figure Description

[0026] Figure 1A schematic diagram of a surge arrester with a series air blowout arc extinguishing gap provided by this utility model;

[0027] Figure 2 A front view structural schematic diagram of the gas blowout extinguishing assembly in a surge arrester with a series gas blowout extinguishing gap provided by this utility model;

[0028] Figure 3 A rear view schematic diagram of the gas blowout extinguishing assembly in a surge arrester with a series gas blowout extinguishing gap provided by this utility model;

[0029] Figure 4 A cross-sectional structural schematic diagram of the gas blowout extinguishing assembly in a surge arrester with a series gas blowout extinguishing gap provided by this utility model;

[0030] Figure 5 A schematic diagram of the compression pipe in a surge arrester with a series air blowout arc extinguishing gap provided by this utility model;

[0031] Figure 6 A schematic cross-sectional view of the compression pipe in a surge arrester with a series air blowout arc extinguishing gap provided by this utility model;

[0032] In the attached diagram: 1. Threaded electrode; 2. Air-blown arc extinguishing assembly; 20. Connecting post; 21. Connecting platform; 22. First connecting sleeve; 23. Second connecting sleeve; 3. Arc blowing port; 4. Skirt; 5. Closed-loop electrode; 6. Intermediate gap; 7. Zinc oxide body; 8. Parallel capacitor; 9. Arc ignition platform; 10. Compression pipe; 11. Annular arc ignition electrode. Detailed Implementation

[0033] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of this invention. Therefore, the drawings and description are considered exemplary in nature and not restrictive.

[0034] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0035] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0036] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0037] The embodiments of this utility model will now be described in detail with reference to the accompanying drawings.

[0038] See Figures 1-6 This utility model proposes a surge arrester with a series air-blown arc-extinguishing gap, including a zinc oxide body 7. An intermediate gap 6 is installed on the upper end of the zinc oxide body 7. A closed-loop electrode 5 is installed on each of the two ends of the intermediate gap 6. The electrode length of the closed-loop electrode 5 is 0.3-0.9m, and the diameter of the two closed-loop electrodes 5 is 9.54-28.65cm to ensure that the power frequency arc has sufficient travel distance and that the arc is effectively extinguished within 1-5ms. The distance between the two closed-loop electrodes 5 is set to 0.29-0.75 times the effective value of the system voltage to ensure that the required operating voltage is achieved and to form an effective insulation connection with the protected equipment. An air-blown arc-extinguishing assembly 2 is connected above the closed-loop electrode 5 on the upper end of the intermediate gap 6. A threaded electrode 1 with an electrode length of 10-15cm is connected to the upper end of the air-blown arc-extinguishing assembly 2. The threaded electrode 1 is connected to a high-voltage line through the upper end of the threaded electrode 1. During use, the arc transmitted to the threaded electrode 1 is extinguished by the air-blown arc-extinguishing assembly 2.

[0039] See Figures 2-6The air-blowing arc extinguishing assembly 2 includes a connecting column 20 sealed at both ends. The connecting column 20 is a solid column structure made of silicone rubber. Multiple mounting slots are provided inside the connecting column 20, each slot being inclined. In the vertical section, one end of the mounting slot is higher than the other end, and the multiple mounting slots are connected end-to-end. An arc-blowing port 3 is provided on the connecting column 20 at the position where the mounting slots meet. The arc-blowing port 3 penetrates the outer wall of the connecting column 20. In this embodiment, the connecting column 20 has 5 mounting slots arranged vertically in a row. Multiple compression pipes 10 are installed in each mounting slot. The compression pipes 10 are ceramic pipes. Both ends of the connector are equipped with annular arc-initiating electrodes 11. Five compression pipes 10 are installed inside the connecting column 20, and these five compression pipes 10 are installed at an angle within the connecting column 20, arranged vertically in a row. In two adjacent compression pipes 10, the annular arc-initiating electrode 11 at the lower end of the upper compression pipe 10 connects to the annular arc-initiating electrode 11 at the upper end of the lower compression pipe 10, forming a connected channel. The annular arc-initiating electrode 11 at the uppermost end of the column of compression pipes 10 connects to the connecting hole. The arc-blowing port 3 is located at... On the outer wall of the connecting column 20, corresponding to the port positions of these compression pipes 10, but no arc-blowing port 3 is provided at the upper end of the uppermost compression pipe 10 in this row, nor at the lower end of the lowermost compression pipe 10 in this row. Therefore, four arc-blowing ports 3 are provided for each of the five arranged compression pipes 10, with two of the four ports forming a group, arranged vertically. The arc-blowing ports 3 communicate with the compression pipes 10. A second connecting sleeve 23 is provided at the top of the connecting column 20, and the upper end of the second connecting sleeve 23 is connected to the upper end of the connecting column 20. The upper end of the second connecting sleeve 23 is connected to the lower end of the threaded electrode 1, and the lower end of the second connecting sleeve 23 is connected to the upper end of the compression pipe 10 installed in the top mounting groove of the connecting column 20. A first connecting sleeve 22 is provided in the connecting column 20 near its lower end. The upper end of the first connecting sleeve 22 is connected to the lower end of the compression pipe 10 installed in the lower mounting groove of the connecting column 20. The lower end of the first connecting sleeve 22 is flush with the lower end of the connecting column 20. A connecting platform 21 is provided on the lower end of the first connecting sleeve 22, and the connecting platform 21 is connected to the upper end of the intermediate gap 6.During a lightning strike, the compression pipe 10 acts as a breakdown channel, allowing the lightning current to flow along its arrangement. Due to the mechanical compression of the compression pipe 10 and the self-magnetic compression of the arc itself, a dual temperature and pressure gradient is generated between the arc inside and outside the compression pipe 10. This causes the arc inside the compression pipe 10 to generate airflow at the annular arc-initiating electrode 11, which then acts on the arc outside the arc-blowing opening 3. Under the influence of the airflow, the arc outside the arc-blowing opening 3 gradually elongates, ultimately extinguishing the arc.

[0040] See Figure 5 and Figure 6 Multiple arc-initiating platforms 9 are provided on the inner wall of the compression pipe 10. The multiple arc-initiating platforms 9 are distributed at equal intervals and are made of copper nails. When lightning strikes, the multiple gaps between the arc-initiating platforms 9 are broken down to guide the lightning to impact the electric arc.

[0041] To ensure that the compression pipe 10 can withstand the ablation effect of electric arcs generated by multiple lightning strikes, a high-density polyethylene coating is provided on the inner wall of the compression pipe 10. The high-density polyethylene coating improves the ablation resistance of the compression pipe 10 and extends its service life.

[0042] To ensure that the connecting post 20 can withstand the ablation effect of electric arcs generated by multiple lightning strikes, a high-density polyethylene coating is also provided on the outer wall of the connecting post 20.

[0043] To prevent the electric arcs outside the two blow-out ports 3 in the same group from connecting, a skirt 4 is provided on the outer wall of the connecting column 20. The skirt 4 has a spiral structure and passes through the middle position of the two blow-out ports 3 in the two groups.

[0044] See Figure 1 A parallel capacitor 8 is connected in parallel across the two ends of the zinc oxide body 7. The parallel capacitor 8 provides a low-impedance path for high-frequency lightning overvoltages, allowing the lightning to discharge to ground quickly. The capacitance of the parallel capacitor 8 is 5–20 nF. Based on the trend of the operating time delay of different sized capacitors connected in parallel under the same voltage, it is found that the parallel capacitor 8 can discharge to ground at 2.59–2.74 times the speed under overvoltage. This effectively improves the operating response speed of the surge arrester to overvoltages, ensuring the safe operation of the equipment.

[0045] The following examples further illustrate the surge arrester with a series magnetic blowout arc extinguishing gap proposed in this application;

[0046] Example 1: A surge arrester with a series air-blown arc-extinguishing gap is used for lightning protection of a 35kV line. The series gap distance is 18.5cm, corresponding to a breakdown voltage of 202kV. The rated voltage of the zinc oxide body is 51kV, the continuous operating voltage is 40.8kV, and the DC 1mA reference voltage is 73kV. The parallel capacitor is a solid-state capacitor with a capacitance of 20nF. This example can be applied to the lightning protection design of overhead collector lines in 35kV wind farms. It can simultaneously utilize the arc-extinguishing function of the air-blown arc-extinguishing device and the zinc oxide body, reliably extinguishing the power frequency arc within 0.3-0.5ms, ensuring the safe operation of the power system. In addition, the parallel capacitor enables the surge arrester to operate quickly, improving its protective performance.

[0047] Example 2: A surge arrester with a series air-blown arc-extinguishing gap is used for lightning protection of a 10kV line. The series gap distance is 10cm, corresponding to a breakdown voltage of 109.2kV. The rated voltage of the zinc oxide body is 17kV, the continuous operating voltage is 13.6kV, and the DC 1mA reference voltage is 25kV. The parallel capacitor is a solid-state capacitor with a capacitance of 20nF. This example can be applied to the lightning protection design of 10kV distribution lines, simultaneously utilizing the arc-extinguishing functions of the air-blown arc-extinguishing device and the zinc oxide body, reliably extinguishing the power frequency arc within 0.3-0.5ms, ensuring the safe operation of the power system. Furthermore, the parallel capacitor enables the surge arrester to operate quickly, improving its protective performance.

[0048] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. It will be apparent to those skilled in the art that this utility model is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or basic characteristics of this utility model. Therefore, the embodiments should be considered exemplary and non-limiting in all respects. The scope of this utility model is defined by the appended claims rather than the foregoing description, and thus all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this utility model. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0049] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that can be understood by those skilled in the art. The above content is only for illustrating the technical concept of this utility model and should not be used to limit the scope of protection of this utility model. Any modifications made to the technical solutions based on the technical concept proposed by this utility model shall fall within the scope of protection of the claims of this utility model.

Claims

1. A surge arrester of series gas blast arc extinction gap, characterized in that, Including zinc oxide body (7), the intermediate gap (6) is installed on the zinc oxide body (7), and the closed loop electrode (5) is installed on the both side ends of the intermediate gap (6) respectively; The upper side of the intermediate gap (6) is connected with the gas blow arc extinguishing assembly (2), the upper side of the gas blow arc extinguishing assembly (2) is connected with the threaded electrode (1), and the threaded electrode (1) is connected with the high-voltage line; The gas blow arc extinguishing assembly (2) includes a connecting column (20), the connecting column (20) is connected with the threaded electrode (1) on the upper side, and the connecting column (20) is connected with the intermediate gap (6) on the lower side; a plurality of compression pipelines (10) are installed in the connecting column (20), the plurality of compression pipelines (10) are connected end to end and are installed in the connecting column (20) in an inclined manner, the connecting column (20) is provided with arc blow openings (3) on the outer wall corresponding to the positions where the compression pipelines (10) are connected end to end, and the arc blow openings (3) are communicated with the compression pipelines (10); The compression pipeline (10) is provided with an arc striking platform (9) in the pipeline.

2. A surge arrester of a series gas blast arc extinction gap according to claim 1, characterized in that, The inner wall of the compression pipeline (10) is provided with a high-density polyethylene coating.

3. The surge arrester of claim 1, wherein, The port of the compression pipeline (10) is provided with an annular arc striking electrode (11).

4. The surge arrester of claim 1, wherein, The connecting column (20) is a columnar structure.

5. The surge arrester of claim 1, wherein, The outer wall of the connecting column (20) is provided with a skirt (4) between the arc blow openings (3).

6. An arrester of a series gas blast arc extinction gap according to claim 5, characterized in that, The skirt (4) is a spiral structure.

7. The surge arrester of claim 1, wherein, The arc striking platform (9) is provided with a plurality of arc striking platforms (9), and the plurality of arc striking platforms (9) are distributed in the compression pipeline (10) at equal intervals.

8. An arrester of a series gas blast arc extinction gap according to claim 7, characterized in that, The arc striking platform (9) is a copper nail.

9. The surge arrester of claim 1, wherein, The both ends of the zinc oxide body (7) are connected with parallel capacitors (8) in parallel.

10. The surge arrester of claim 1, wherein, The electrode length of the threaded electrode (1) is 10-15 cm.

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