Lightning protection device and method for 10kV distribution line

Abstract

The invention provides a lightning protection device for a 10kV distribution line, which comprises an arc extinguishing insulator arranged between parallel high-voltage lines, and is characterized in that the arc extinguishing insulator comprises a cylinder, fins and a blowing control valve; the two ends of the column body are connected with a high-voltage line in a supporting mode through fastening bases respectively, a center cavity is formed in the column body, the fins are arranged outside the column body in an array mode in the axial direction, and blowing nozzles communicated with the center cavity and the outside are arranged on the portion, between the adjacent fins, of the column body. A gas production material is arranged in the central cavity, and the temperature of the gas production material rises under the action of lightning strike and generates high-pressure gas; the air blowing control valve is arranged between the central cavity and the air blowing nozzle and is opened under the action of temperature and / or air pressure change, so that high-pressure air in the central cavity is discharged from the air blowing nozzle and blows off electric arcs outside the column body, the insulating strength of the insulating column body is quickly recovered, a distribution line is effectively protected, the lightning trip-out rate is reduced, and the service life of the distribution line is prolonged. And the lightning protection period is prolonged.

Description

Technical Field

[0001] The invention relates to a lightning protection technology for a power distribution line, and in particular provides a lightning protection device and a protection method for a 10kV power distribution line. Background Art

[0002] 10kV distribution lines are an important part of the power system and play an important role in supplying power to various cities and towns. During the use of 10kV distribution lines, lightning is an important factor affecting the safety of distribution lines, and has long been the first cause of line fault tripping. The thunderstorm season is a high-incidence season for distribution line fault tripping. Once a fault occurs, the workload of inspection and processing is very large and inefficient. Power outages will not only cause economic losses to varying degrees, but also directly affect the lives of the majority of residents. Therefore, how to improve the lightning resistance, lightning protection and lightning induction level of 10kV distribution lines is of great engineering practical significance.

[0003] Lightning tripping is an important issue that affects the safe operation of power systems. The grounding channel formed by lightning flashover is the main cause of short-circuit failures in the system and lightning tripping.

[0004] At present, lightning protection devices for distribution lines generally do not have arc extinguishing capabilities. The traditional parallel gap forms a protective gap by installing metal electrodes in parallel at both ends of the insulator string. Although some distribution lines have installed jet gas arc extinguishing lightning protection devices at the insulator string, which can extinguish the follow-current arc to a certain extent, this type of arc extinguishing device is mostly a one-time product and is limited by the number of operations. Summary of the invention

[0005] To this end, the present invention provides a lightning protection device and a protection method for a 10kV distribution line, so as to effectively protect the distribution line and reduce the lightning tripping rate, and to increase the lightning protection period of the device.

[0006] In order to achieve the above-mentioned purpose, the present invention provides a lightning protection device for a 10kV distribution line, comprising an arc-extinguishing insulator arranged between parallel high-voltage lines, the arc-extinguishing insulator comprising a column, fins and an air blowing control valve; the two ends of the column are respectively connected to the high-voltage line support through a fastening seat and a central cavity is arranged inside, the fins are arranged outside the column along an axial array, and the column is located between adjacent fins and is provided with an air blowing nozzle connecting the central cavity with the outside; a gas-producing material is arranged in the central cavity, and the temperature of the gas-producing material increases and high-pressure gas is generated under the action of lightning strike; the air blowing control valve is arranged between the central cavity and the air blowing nozzle, and the air blowing control valve is opened by the temperature and / or air pressure changes, so that the high-pressure air in the central cavity is discharged by the air blowing nozzle and blows off the arc outside the column.

[0007] Furthermore, each of the fins extends outwardly in the radial direction of the column and is provided with an arc-shaped groove on the outer edge in the same direction, and the air blowing nozzle is arranged on the column near the arc-shaped groove to achieve arc concentration through the arc-shaped groove.

[0008] Furthermore, the fins are symmetrically provided with the arc-shaped grooves on both sides of the high-voltage line, and the two sides of the column are respectively provided with air blowing nozzles facing the house-shaped grooves to concentrate the flashover arc in the arc-shaped grooves away from the high-voltage line.

[0009] Furthermore, the blowing control valve includes a valve sleeve, an outer valve core and a shape memory alloy body. The valve sleeve is arranged along the radial direction of the column and the outer end is connected to the inner wall of the column. The valve sleeve is located at one end of the central cavity and is provided with an outer wall air inlet hole, and is located at one end of the blowing nozzle and is provided with an exhaust hole. The outer valve core is slidably arranged in the valve sleeve and is provided with an inner wall air inlet hole near one end of the central cavity. The shape memory alloy body is arranged between the valve sleeve and the inner wall of the column and controls the sliding of the outer valve core: under normal temperature conditions, the shape memory alloy body contracts and drives the outer valve core to slide outward, so that the outer wall air inlet hole and the inner wall air inlet hole are staggered and no air is ventilated; under high temperature conditions, the shape memory alloy body stretches and drives the outer valve core to slide inward, so that the outer wall air inlet hole and the inner wall air inlet hole are aligned and ventilation is achieved.

[0010] Furthermore, the blowing control valve also includes an inner valve core and a rigid spring member, the inner valve core is slidably arranged in the outer valve core and is provided with an inner cavity with an outer end blocked, a radial hole communicating with the inner cavity is provided near the outer end of the inner valve core, and the rigid spring member is arranged between the outer valve core and the inner valve core and controls the sliding of the inner valve core: under the low pressure condition of the central cavity, the rigid spring member is in an extended state and exerts an inward elastic force on the inner valve core, and the radial hole of the inner valve core is blocked by the outer valve core and is not ventilated; under the high pressure condition of the central cavity, after the air pressure in the central cavity rises to a level greater than the force of the rigid spring member, the inner valve core moves outward until the radial hole is exposed by the outer valve core and ventilation occurs.

[0011] Furthermore, the column is located between adjacent fins and is provided with a central exhaust hole and outer exhaust holes, the central exhaust hole is toward the center of the arc-shaped groove, and the outer exhaust holes are provided on both sides of the central exhaust hole and are respectively toward the two ends of the arc-shaped groove; the outer end of the valve sleeve is connected to the central exhaust hole, and an outer exhaust hole connected to the outer blowing nozzle is provided near the outer end of the valve sleeve.

[0012] Furthermore, two eccentric sealing plates extending axially are arranged in the central cavity of the cylinder, and the eccentric sealing plates separate the central cavity from the blowing nozzle on the same side. The gas-producing material is arranged between the two eccentric sealing plates, and the blowing control valve is arranged on the eccentric sealing plates and controls the connection between the central cavity and the blowing nozzle.

[0013] Furthermore, the column, fins and eccentric sealing plates of the arc-extinguishing insulator are an integrated structure, and a gas-producing material delivery port is provided at the end of the locking column between the two eccentric sealing plates. The gas-producing material delivery port is provided with a detachable sealing end cover to enable replacement of the gas-producing material.

[0014] In order to achieve the above object, in a second aspect, the present invention provides a protection method for a 10kV distribution line, using the lightning protection device for the 10kV distribution line, the steps comprising:

[0015] S1O0. In normal weather, the gas-generating material does not generate gas at room temperature, the central cavity is kept at normal pressure, and the blowing control valve remains closed at normal temperature and pressure;

[0016] S200. In thunderstorm weather, the arc-extinguishing insulator or high-voltage line is struck by lightning, an arc is generated outside the arc-extinguishing insulator and the temperature rises rapidly, the gas-generating material is heated to generate high-pressure gas, the pressure of the central cavity increases, the air blowing control valve is subjected to high temperature and / or high pressure and turns to an open state, the high-pressure gas in the central cavity is discharged from the air blowing nozzle, and the arc outside the arc-extinguishing insulator is blown out;

[0017] S300. After the arc is blown out, the temperature of the arc-extinguishing insulator decreases, the gas-generating material stops producing high-pressure gas, the pressure of the central cavity decreases, and the blowing control valve is closed again under normal temperature and pressure conditions;

[0018] In normal weather conditions in the future, the gas-generating material does not generate gas at room temperature, and the central cavity maintains a normal pressure state. The air blowing control valve remains closed at room temperature and pressure to achieve sealed protection for the gas-generating material, so that the arc extinguishing operation can be performed again when lightning strikes next time, and it can be reused to improve the long-term effect of lightning protection.

[0019] Furthermore, the protection method for the 10kV distribution line includes: each of the fins extends outward along the radial direction of the column and an arc-shaped groove is provided on the outer edge in the same direction, and the air blowing nozzle is provided on the column near the arc-shaped groove; in thunderstorm weather, the arc-extinguishing insulator and / or the high-voltage line is struck by lightning, an arc is generated and concentrated in the arc-shaped groove, the gas-producing material generates high-pressure gas, and the pressure in the central cavity increases, the air blowing control valve is transformed into an open state due to the high temperature and / or high pressure, and the high-pressure gas is discharged from the air blowing nozzle to blow off the arc at the arc-shaped groove.

[0020] The technical advantages of the lightning protection device and protection method for a 10kV distribution line provided are at least reflected in:

[0021] 1. An arc-extinguishing insulator is arranged between parallel high-voltage lines. The column of the arc-extinguishing insulator is provided with an air blowing nozzle between the fins. The temperature of the gas-producing material in the central cavity increases under the action of lightning strike to generate high-pressure gas, and the air blowing control valve is opened by the temperature and / or air pressure change, and the high-pressure air is discharged from the air blowing nozzle and blows off the arc outside the column. This device allows lightning flashover during use, and the high-pressure gas in the central cavity is ejected from the air blowing nozzle to blow off the arc, so that the insulation strength of the insulating column is quickly restored, the lightning trip rate is reduced, and the requirements for the ground grid resistance are reduced;

[0022] 2. After the arc is blown out, the temperature of the arc-extinguishing insulator decreases, the gas-producing material stops producing high-pressure gas, and the pressure in the central cavity decreases. The air blowing control valve is closed again under normal temperature and pressure conditions to seal and protect the gas-producing material in the central cavity to prevent it from failing due to external interference, so that the arc-extinguishing insulator can play a role again when struck by lightning again. The gas-producing material discharges high-pressure gas again under high-temperature conditions of lightning strike to perform arc extinguishing operation, so that it can be reused many times to achieve long-term lightning protection;

[0023] 3. Each of the fins of the arc-extinguishing insulator extends radially outwardly along the column and is provided with an arc-shaped groove on the outer edge in the same direction. The air blowing nozzle is provided on the column near the arc-shaped groove. In thunderstorm weather, the arc-extinguishing insulator and / or the high-voltage line are struck by lightning, an arc is generated and concentrated at the arc-shaped groove, the gas-generating material generates high-pressure gas, and the pressure of the central cavity increases. The air blowing control valve is turned into an open state, and the high-pressure gas is discharged from the air blowing nozzle to blow off the arc at the arc-shaped groove, thereby realizing centralized control of the arc and centralized discharge of the high-pressure gas, blowing out the centrally controlled arc, and improving the arc extinguishing effect;

[0024] 4. The shape memory alloy body of the blowing control valve is arranged between the valve sleeve and the inner wall of the column, and the shape memory alloy body expands and contracts under the influence of temperature to realize the on-off control of the blowing nozzle; at the same time, the inner valve core of the blowing control valve is slidably arranged in the outer valve core and is provided with an inner cavity with an outer end blocked, and a radial hole connected to the inner cavity is provided near the outer end of the inner valve core. The rigid spring member is arranged between the outer valve core and the inner valve core and controls the sliding of the inner valve core. The on-off control of the blowing nozzle is realized by the change of the internal pressure of the central cavity caused by the gas production of the gas producing material. The changes in temperature and pressure can cause the connection of the blowing nozzle, thereby realizing blowing to the external arc, thereby improving the sensitivity of the blowing control, thereby improving the lightning protection effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings required for use in the embodiments of the present disclosure will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on the drawings without creative work.

[0026] Figure 1 It is a three-dimensional structural schematic diagram of an embodiment of a lightning protection device for a 10kV distribution line provided;

[0027] Figure 2 It is a front view of an embodiment of a lightning protection device for a 10kV power distribution line provided;

[0028] Figure 3 It is a top view of an embodiment of a lightning protection device for a 10kV distribution line provided;

[0029] Figure 4 is a schematic diagram of a three-dimensional structure of an embodiment of the provided composite insulator;

[0030] Figure 5 is a front view of an embodiment of the provided insulator;

[0031] Figure 6 yes Figure 5 A cross-sectional view in the AA direction;

[0032] Figure 7 yes Figure 5 CC view of the cross section;

[0033] Figure 8 yes Figure 7 A partial schematic diagram of the right part of FIG.

[0034] Fig. 9 It is a schematic diagram of the state in which the outer valve core of the composite air blowing valve is opened by the memory alloy to blow air outwards;

[0035] Fig.10 It is a schematic diagram of the state in which the outer valve core of the composite air blowing valve is opened by the memory alloy and the inner valve core is opened by the pressure to blow air outward at the same time;

[0036] Fig.11 It is a flowchart of an embodiment of the protection method for 10kV distribution lines provided.

[0037] Description of the accompanying drawings:

[0038] e-arc-extinguishing insulator, f-high voltage line;

[0039] 1-column, 11-blowing nozzle;

[0040] 2-fin, 21-arc groove;

[0041] 3- Fastening seat;

[0042] 4- Gas-generating materials;

[0043] 5-air blowing control valve, 51-valve sleeve, 52-external valve core, 53-inner valve core, 54-shape memory alloy body, 55-rigid spring member;

[0044] 6-Eccentric sealing plate. DETAILED DESCRIPTION

[0045] During the use of 10kV distribution lines, lightning is an important factor affecting the safety of distribution lines, and has long been the number one cause of line fault tripping. Lightning tripping is an important issue that affects the safe operation of the power system. The grounding channel formed by lightning flashover is the main cause of short-circuit faults in the system and lightning tripping. At present, lightning protection devices for distribution lines generally do not have arc extinguishing capabilities. The traditional parallel gap forms a protective gap by installing metal electrodes in parallel at both ends of the insulator string. Although some distribution lines are equipped with a jet gas arc extinguishing lightning protection device at the insulator string, which can extinguish the follow-current arc to a certain extent. However, this type of arc extinguishing device is mostly a one-time product and is limited by the number of actions.

[0046] To this end, the present invention provides a lightning protection device and a protection method for a 10kV distribution line, comprising an arc-extinguishing insulator arranged between parallel high-voltage lines, the arc-extinguishing insulator comprising a column, fins and an air blowing control valve; both ends of the column are respectively connected to the high-voltage line support through a fastening seat and a central cavity is arranged inside, the fins are arranged outside the column along an axial array, and the column is located between adjacent fins and is provided with an air blowing nozzle connecting the central cavity and the outside; a gas-producing material is arranged in the central cavity, and the temperature of the gas-producing material increases and high-pressure gas is generated under the action of lightning strike; the air blowing control valve is arranged between the central cavity and the air blowing nozzle, and the air blowing control valve is opened by the temperature and / or air pressure changes, so that the high-pressure air in the central cavity is discharged by the air blowing nozzle and blows off the arc outside the column, so that the insulation strength of the insulating column is quickly restored, the distribution line is effectively protected, the lightning tripping rate is reduced, and the lightning protection period is increased.

[0047] The embodiments of the present disclosure are further described in detail below in conjunction with the accompanying drawings and examples. The detailed descriptions and drawings of the following embodiments are used to exemplarily illustrate the principles of the present disclosure, but cannot be used to limit the scope of the present disclosure, that is, the present disclosure is not limited to the described embodiments. Some embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. The features in the following embodiments can be combined with each other without conflict.

[0048] like Figure 1 , Figure 2 and Figure 3As shown, the present invention provides a lightning protection device for a 10kV distribution line, comprising an arc-extinguishing insulator e arranged between parallel high-voltage lines f, the arc-extinguishing insulator e comprising a column 1, fins 2 and a blowing control valve 5; the two ends of the column 1 are respectively supported and connected to the high-voltage line f by a fastening seat 3 and a central cavity is arranged inside, the fins 2 are arranged outside the column 1 along an axial array, and the column 1 is provided with a blowing nozzle 11 connecting the central cavity with the outside between adjacent fins 2; a gas-generating material 4 is arranged in the central cavity, and the temperature of the gas-generating material 4 increases and generates high-pressure gas under the action of lightning strike; the blowing control valve 5 is arranged between the central cavity and the blowing nozzle 11, and the blowing control valve 5 is opened by the change of temperature and / or air pressure, so that the high-pressure air in the central cavity is discharged by the blowing nozzle 11 and blows off the arc outside the column 1.

[0049] A lightning protection device for a 10kV power distribution line is provided, wherein an arc-extinguishing insulator e is arranged between parallel high-voltage lines, a column 1 of the arc-extinguishing insulator e is located between fins 2 and an air blowing nozzle 11 is arranged, a gas-generating material 4 in a central cavity increases in temperature under the action of lightning strike to generate high-pressure gas, and an air blowing control valve 5 is opened by the temperature and / or air pressure change, and high-pressure air is discharged from the air blowing nozzle and blows off the arc outside the column 1; during use, the device allows lightning flashover, and the arc is blown off by the high-pressure gas in the central cavity being ejected from the air blowing nozzle 11, so that the insulation strength of the insulating column 1 is quickly restored, the lightning tripping rate is reduced, and the requirements for the ground grid resistance are reduced.

[0050] like Fig.11 As shown, based on the lightning protection device for the 10kV distribution line, the present invention provides a protection method for a 10kV distribution line, comprising:

[0051] S1O0. In normal weather, the gas-generating material 4 does not generate gas at room temperature, the central cavity is kept at normal pressure, and the blowing control valve 5 remains closed at normal temperature and pressure;

[0052] S200. In thunderstorm weather, the arc-extinguishing insulator e or the high-voltage line f is struck by lightning, an arc is generated outside the arc-extinguishing insulator e and the temperature rises rapidly, the gas-generating material 4 is heated to generate high-pressure gas, and the pressure in the central cavity increases. The air blowing control valve 5 is subjected to high temperature and / or high pressure and turns to an open state, and the high-pressure gas in the central cavity is discharged from the air blowing nozzle 11 to blow out the arc outside the arc-extinguishing insulator e;

[0053] S300. After the arc is blown out, the temperature of the arc-extinguishing insulator e decreases, the gas-generating material 4 stops generating high-pressure gas, the pressure in the central cavity decreases, and the blowing control valve 5 is closed again under normal temperature and pressure conditions.

[0054] Based on the above process, after the arc is blown out, the temperature of the arc-extinguishing insulator e decreases, the gas-producing material 4 stops producing high-pressure gas, and the pressure in the central cavity decreases. The blowing control valve 5 is closed again under normal temperature and pressure conditions, and the gas-producing material 4 in the central cavity is sealed and protected to prevent failure due to external interference, so that the arc-extinguishing insulator can play a role again when struck by lightning again. The gas-producing material 4 discharges high-pressure gas under the high temperature conditions of lightning strike to perform arc extinguishing operation, so that it can be reused many times to achieve long-term lightning protection.

[0055] like Figure 1 , Figure 4 , Figure 5 and Figure 6 As shown, in some embodiments, each of the fins 2 extends outward along the radial direction of the column 1 and is provided with an arc-shaped groove 21 on the outer edge in the same direction, and the air blowing nozzle 11 is provided on the column 1 near the arc-shaped groove 21. Furthermore, the fins 2 are symmetrically provided with the arc-shaped grooves 21 on both sides of the high-voltage line f, and the two sides of the column 1 are respectively provided with air blowing nozzles 11 facing the grooves of the house type. In thunderstorm weather, the arc-extinguishing insulator e and / or the high-voltage line f are struck by lightning, an arc is generated and concentrated at the arc-shaped groove 21, the gas-generating material 4 generates high-pressure gas, and the pressure of the central cavity increases. The air blowing control valve 5 is subjected to the high temperature and / or high pressure and is transformed into an open state, and the high-pressure gas is discharged from the air blowing nozzle 11 to blow off the arc at the arc-shaped groove 21.

[0056] Based on the above embodiment, each of the fins of the arc extinguishing insulator extends outward along the radial direction of the column and an arc-shaped groove 21 is provided on the outer edge in the same direction. The air blowing nozzle 11 is provided on the column 1 near the arc-shaped groove 21. In thunderstorm weather, the arc extinguishing insulator and the high-voltage line are struck by lightning, an arc is generated and concentrated at the arc-shaped groove, the gas-producing material generates high-pressure gas, and the pressure in the central cavity increases. The air blowing control valve is changed to an open state, and the high-pressure gas is discharged by the air blowing nozzle 11 to blow off the arc at the arc-shaped groove, thereby realizing centralized control of the arc and centralized discharge of high-pressure gas, blowing out the centrally controlled arc, and improving the arc extinguishing effect.

[0057] like Figure 5 , Figure 6 and Figure 7 As shown, in some embodiments, the column 1 is located between adjacent fins 2 and is provided with a central exhaust hole and outer exhaust holes, the central exhaust hole is facing the center position of the arc-shaped groove 21, and the outer exhaust holes are provided on both sides of the central exhaust hole and are respectively facing near the two ends of the arc-shaped groove 21; the outer end of the valve sleeve 51 is connected to the central exhaust hole, and an outer exhaust hole connected to the outer blowing nozzle 11 is provided near the outer end of the valve sleeve 51, so as to expand the blowing range to the arc-shaped groove 21 and improve the blowing effect.

[0058] In some embodiments, two eccentric sealing plates 55 extending axially are provided in the central cavity of the column 1, and the eccentric sealing plates 55 separate the central cavity from the blowing nozzle 11 on the same side. The gas-generating material 4 is arranged between the two eccentric sealing plates 55, and the blowing control valve 5 is arranged on the eccentric sealing plates 55 and controls the connection and disconnection between the central cavity and the blowing nozzle 11, thereby realizing blowing control on both sides.

[0059] The column 1, fins 2 and eccentric sealing plate 55 of the arc-extinguishing insulator e are an integrated molding structure. The end of the locking column 1 is located between the two eccentric sealing plates 55 and is provided with a gas-producing material 4 delivery port. The gas-producing material 4 delivery port is provided with a detachable sealing end cover to facilitate the replacement of the gas-producing material without disassembling the insulator of the high-voltage line. The gas-producing material is used in the form of arc-extinguishing sheets, arc-extinguishing skeletons, arc-extinguishing covers, arc-extinguishing side plates, etc. At present, the most widely used is PA, which has the advantages of large gas production, high breakdown voltage, less residual carbon, high mechanical properties and excellent temperature resistance. As a thermoplastic material, PA is also one of the preferred ablative materials.

[0060] like Figure 7 , Figure 8 , Fig. 9 and Fig.10 As shown, in some embodiments, the blowing control valve 5 includes a valve sleeve 51, an outer valve core 52 and a shape memory alloy body 54, the valve sleeve 51 is arranged along the radial direction of the column 1 and the outer end is connected to the inner wall of the column 1, the valve sleeve 51 is provided with an outer wall air inlet hole at one end of the central cavity, and an exhaust hole is provided at one end of the blowing nozzle 11, the outer valve core 52 is slidably arranged in the valve sleeve 51 and is provided with an inner wall air inlet hole near one end of the central cavity, the shape memory alloy body 54 is arranged between the valve sleeve 51 and the inner wall of the column 1 and controls the sliding of the outer valve core 52: under normal temperature conditions, the shape memory alloy body 54 contracts and drives the outer valve core 52 to slide outward, so that the outer wall air inlet hole and the inner wall air inlet hole are staggered and not ventilated; under high temperature conditions, the shape memory alloy body 54 stretches and drives the outer valve core 52 to slide inward, so that the outer wall air inlet hole and the inner wall air inlet hole are aligned and ventilated.

[0061] like Figure 7 , Figure 8 , Fig. 9 and Fig.10As shown, further, the blowing control valve 5 also includes an inner valve core 53 and a rigid spring member 55, the inner valve core 53 is slidably arranged in the outer valve core 52 and is provided with an inner cavity with an outer end blocked, a radial hole communicating with the inner cavity is provided near the outer end of the inner valve core 53, and the rigid spring member 55 is arranged between the outer valve core 52 and the inner valve core 53 and controls the sliding of the inner valve core 53: under the low pressure condition of the central cavity, the rigid spring member 55 is in an extended state and exerts an inward elastic force on the inner valve core 53, and the radial hole of the inner valve core 53 is shielded by the outer valve core 52 and is not ventilated; under the high pressure condition of the central cavity, after the air pressure in the central cavity rises to a level greater than the force of the rigid spring member 55, the inner valve core 53 moves outward until the radial hole is exposed by the outer valve core 52 and is ventilated.

[0062] The shape memory alloy body 54 of the blowing control valve 5 is arranged between the valve sleeve 51 and the inner wall of the column. The shape memory alloy body 54 expands and contracts under the influence of temperature to realize the on-off control of the blowing nozzle 11. At the same time, the inner valve core 53 of the blowing control valve 5 is slidably arranged in the outer valve core 52 and is provided with an inner cavity with an outer end blocked. The rigid spring member 55 is arranged between the outer valve core 52 and the inner valve core 53 and controls the sliding of the inner valve core 53. The on-off control of the blowing of the blowing nozzle 11 is realized by the change of the internal pressure of the central cavity caused by the gas production of the gas producing material 4. The changes in temperature and pressure can cause the connection of the blowing nozzle, thereby realizing blowing to the external arc, improving the sensitivity of the blowing control, and thus improving the lightning protection effect.

[0063] A lightning protection device for a 10kV distribution line is provided. Through ultra-fast and ultra-strong arc extinguishing capability, the arc building process corresponding to each pulse under multi-pulse lightning conditions can be effectively suppressed, ensuring that there will be no tripping under multi-pulse lightning conditions, thereby achieving the goal of preventing lightning tripping, reducing dependence on ground grid resistance, and effectively protecting power equipment, reducing equipment damage rate, extending equipment service life, and improving the safety and reliability of distribution lines.

[0064] Although the present disclosure has been described with reference to preferred embodiments, various modifications may be made thereto and parts thereof may be replaced with equivalents without departing from the scope of the present disclosure. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there is no structural conflict. The present disclosure is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A lightning protection device for a 10kV distribution line, characterized in that: It comprises an arc-extinguishing insulator (e) arranged between parallel high-voltage lines (f), wherein the arc-extinguishing insulator (e) comprises a column (1), fins (2) and an air blowing control valve (5); The two ends of the column (1) are respectively connected to the high-voltage line (f) through a fastening seat (3) and a central cavity is provided inside. The fins (2) are arranged outside the column (1) along an axial array. The column (1) is provided with a blowing nozzle (11) connecting the central cavity with the outside between adjacent fins (2); A gas-generating material (4) is arranged in the central cavity, and the temperature of the gas-generating material (4) increases under the action of lightning strike and generates high-pressure gas; The air blowing control valve (5) is arranged between the central cavity and the air blowing nozzle (11), and the air blowing control valve (5) is opened by the change of temperature and / or air pressure, so that the high-pressure air in the central cavity is discharged from the air blowing nozzle (11) and blows off the arc outside the column (1).

2. The lightning protection device for a 10kV distribution line according to claim 1 is characterized in that: Each of the fins (2) extends outward in the radial direction of the column (1) and is provided with an arc-shaped groove (21) on the outer edge in the same direction. The air blowing nozzle (11) is arranged on the column (1) near the arc-shaped groove (21).

3. The lightning protection device for a 10kV distribution line according to claim 2 is characterized in that: The fins (2) are symmetrically provided with arc-shaped grooves (21) on both sides of the high-voltage wire (f), and the column (1) is provided with air blowing nozzles (11) facing the house-shaped grooves on both sides.

4. The lightning protection device for a 10kV distribution line according to claim 1 is characterized in that: The blowing control valve (5) comprises a valve sleeve (51), an outer valve core (52) and a shape memory alloy body (54); the valve sleeve (51) is arranged along the radial direction of the column (1) and the outer end is connected to the inner wall of the column (1); the valve sleeve (51) is provided with an outer wall air inlet hole at one end of the central cavity and an exhaust hole at one end of the blowing nozzle (11); the outer valve core (52) is slidably arranged in the valve sleeve (51) and is provided with an inner wall air inlet hole near one end of the central cavity; The shape memory alloy body (54) is arranged between the valve sleeve (51) and the inner wall of the column (1) and controls the sliding of the outer valve core (52): under normal temperature conditions, the shape memory alloy body (54) contracts and drives the outer valve core (52) to slide outward, so that the outer wall air inlet hole and the inner wall air inlet hole are staggered and no ventilation occurs; under high temperature conditions, the shape memory alloy body (54) stretches and drives the outer valve core (52) to slide inward, so that the outer wall air inlet hole and the inner wall air inlet hole are aligned and ventilation occurs.

5. The lightning protection device for 10kV power distribution line according to claim 4 is characterized in that: The blowing control valve (5) further comprises an inner valve core (53) and a rigid spring member (55), wherein the inner valve core (53) is slidably arranged in the outer valve core (52) and is provided with an inner cavity whose outer end is blocked, and a radial hole communicating with the inner cavity is provided near the outer end of the inner valve core (53), and the rigid spring member (55) is arranged between the outer valve core (52) and the inner valve core (53) and controls the sliding of the inner valve core (53): under the condition of low pressure in the central cavity, the rigid spring member (55) is in an extended state and exerts an inward elastic force on the inner valve core (53), and the radial hole of the inner valve core (53) is shielded by the outer valve core (52) and is not ventilated; under the condition of high pressure in the central cavity, after the air pressure in the central cavity rises to a value greater than the force of the rigid spring member (55), the inner valve core (53) moves outward until the radial hole is exposed from the outer valve core (52) and is ventilated.

6. The lightning protection device for 10kV power distribution line according to claim 5 is characterized in that: The column (1) is provided with a central exhaust hole and an outer exhaust hole between adjacent fins (2), the central exhaust hole facing the center position of the arc-shaped groove (21), and the outer exhaust holes are provided on both sides of the central exhaust hole and respectively facing the vicinity of the two ends of the arc-shaped groove (21); the outer end of the valve sleeve (51) is connected to the central exhaust hole, and the outer exhaust hole connected to the outer blowing nozzle (11) is provided near the outer end of the valve sleeve (51).

7. The lightning protection device for 10kV power distribution line according to claim 6 is characterized in that: Two eccentric sealing plates (55) extending in the axial direction are arranged in the central cavity of the column (1), and the eccentric sealing plates (55) separate the central cavity from the blowing nozzle (11) on the same side. The gas-generating material (4) is arranged between the two eccentric sealing plates (55), and the blowing control valve (5) is arranged on the eccentric sealing plates (55) and controls the connection and disconnection between the central cavity and the blowing nozzle (11).

8. The lightning protection device for 10kV power distribution line according to claim 7, characterized in that: The column (1), fins (2) and eccentric sealing plates (55) of the arc-extinguishing insulator (e) are an integrated structure, and a gas-producing material (4) delivery port is provided between two eccentric sealing plates (55) at the end of the locking column (1), and the gas-producing material (4) delivery port is provided with a detachable sealing end cover.

9. A method for protecting a 10kV distribution line, using the lightning protection device for a 10kV distribution line according to claim 1, characterized in that: S1O0. In normal weather, the gas-generating material (4) does not generate gas at room temperature, the central cavity is kept at normal pressure, and the blowing control valve (5) remains closed at room temperature and pressure; S200. In thunderstorm weather, the arc-extinguishing insulator (e) or the high-voltage line (f) is struck by lightning, an arc is generated outside the arc-extinguishing insulator (e) and the temperature rises rapidly, the gas-generating material (4) is heated to generate high-pressure gas, the pressure of the central cavity increases, the air blowing control valve (5) is subjected to the high temperature and / or high pressure and changes to an open state, the high-pressure gas in the central cavity is discharged from the air blowing nozzle (11), and the arc outside the arc-extinguishing insulator (e) is blown out; S300. After the arc is blown out, the temperature of the arc-extinguishing insulator (e) decreases, the gas-generating material (4) stops generating high-pressure gas, the pressure in the central cavity decreases, and the blowing control valve (5) is closed again under normal temperature and pressure conditions.

10. The protection method for a 10 kV distribution line according to claim 9, characterized in that: Each of the fins (2) extends outward in the radial direction of the column (1) and is provided with an arc-shaped groove (21) on the outer edge in the same direction, and the air blowing nozzle (11) is provided on the column (1) near the arc-shaped groove (21); In thunderstorm weather, the arc-extinguishing insulator (e) and / or the high-voltage line (f) are struck by lightning, an arc is generated and concentrated at the arc-shaped groove (21), the gas-generating material (4) generates high-pressure gas, the pressure in the central cavity increases, the air blowing control valve (5) is subjected to the high temperature and / or high pressure and changes to an open state, the high-pressure gas is discharged from the air blowing nozzle (11), and the arc at the arc-shaped groove (21) is blown off.

Images