Fully insulated separable external series fixed-gap lightning arrester for live working

Abstract

A fully-insulated separable external series fixed-gap lightning arrester device for live working, comprising: detachable line clamps, high-voltage leads, lightweight insulating cavities, upper contacts, upper insulating waterproof piston rings, lightning arrester bodies, lower insulating waterproof piston rings, contact rings, contact piece fixing rings, contact pieces, elastic tension springs, metal brackets, live installation brackets, separators, disconnectors, external series fixed-gap parts, etc. It is mainly applied to prevent lightning strikes and break lines and power frequency follow current in distribution network lines. The device is fully insulated; the existence of the external series fixed gap isolates the power frequency voltage, and the lightning arrester is not energized under normal line conditions, greatly reducing the aging rate and increasing the service life; after the lightning arrester is damaged, the lightning arrester body and the entire lightning arrester device can be installed or disassembled by live working with an insulating operating rod; live working can be carried out during the initial installation, improving the maintenance efficiency; reducing the lightning arrester cross arms, increasing the line corridor and aesthetics, reducing the construction cost, and improving the line insulation level.

Description

Technical Field:

[0001] The present invention relates to the research and development and design field of separable externally series-connected fixed-gap lightning arresters. Specifically, it relates to a fully insulated separable externally series-connected fixed-gap lightning arrester for live working. Background Art:

[0002] To prevent the increasingly serious problems of overhead distribution insulated wires being broken by lightning strikes and tripping caused by power frequency follow current, currently, composite outer-covering externally fixed-gap metal oxide lightning arresters are gradually installed beside the tower insulators. For example, a line-type fixed-gap metal oxide lightning arrester disclosed in CN203659557U is to integrally connect the high-voltage end of the currently widely used traditional silicone rubber composite outer-covering metal oxide lightning arrester to a silicone rubber composite outer-covering insulator with a fixed gap. The main purpose is to isolate the power frequency voltage with an air gap, and there is no need to manually adjust the distance between the upper and lower electrodes of the air gap during installation. However, there are still deficiencies. The main drawbacks are that the high-voltage end of the lightning arrester is integrally connected to the silicone rubber composite outer-covering insulator with a fixed gap. Once the lightning arrester or the gap insulator is damaged, they have to be replaced together; it is difficult to install or disassemble during live working. When routine inspection or damage of the lightning arrester occurs, it often waits for power outage for disassembly inspection or replacement. During the replacement period, if there are lightning strikes and overvoltage attacks again, it cannot continue to play a protective role. In places with conditions, an insulated boom truck is used for live working, which consumes a large amount of manpower and material resources and is restricted by the terrain; the exposed flexible silicone rubber composite outer-covering of the lightning arrester and the insulator is prone to aging and cracking, and being pecked by birds in the natural environment, reducing the service life; once the lightning arrester without outer-covering protection fails and explodes, the splashing metal oxide is likely to damage other electrical equipment and passers-by.

[0003] Another type of drop-type lightning arrester disclosed in CN201320171068.7 is to modify a zinc oxide lightning arrester and install it on the drop-type mechanism of the original drop-type fuse, so as to detect, repair and replace the lightning arrester with an insulating operating rod without power outage. Its disadvantages are that the drop mechanism has a complex structure, high processing cost and troublesome assembly; the main electrical components are exposed and prone to aging, pollution flashover and short circuit, affecting the overall insulation design process; when the lightning arrester body is closed, the elastic piece is compressed and energized, prone to fatigue failure, and when the disconnector itself fails, it will cause the drop mechanism to fail and the line lightning protection to be ineffective; the drop mechanism is also installed outdoors on the line cross-arm, and the lightning arrester has a relatively short service life among overhead line equipment, is easy to be damaged, and inspection, maintenance and replacement are currently prominent and troublesome problems for the power department. Especially, the exposed part of the zinc oxide lightning arrester is made of silicone rubber, and silicone rubber products are prone to aging and cracking and being pecked by birds in the natural environment, reducing the service life. There are many electrical connection points, that is, there are many electrical fault points, which also affect the overall line insulation and aesthetics; there is no fixed gap setting. Although the damaged lightning arrester body can be removed and replaced with power when it is damaged, the drop-type lightning arrester must be equipped with a disconnector. The lightning protection of overhead distribution lines generally uses lightning arresters with fixed gaps, and lightning arresters with fixed gaps are not suitable for supporting disconnectors and cannot be used. The integration degree is not high and it is relatively heavy.

[0004] Another type is the chamber lightning arrester, which mainly moves the zinc oxide lightning arrester body indoors from outdoors to reduce the influence of the natural environment on the lightning arrester body; the lightning arrester can be detected, repaired and replaced with an insulating operating rod. However, there is no fixed gap insulator. With the existence of the fixed gap insulator, the lightning arrester body is not charged under normal operation, and the aging rate of the lightning arrester is greatly reduced; although it has the function of quickly replacing the lightning arrester body with live working, it does not have the function of quickly and simply installing and disassembling the lightning arrester with live working; the porcelain outer casing is heavy and fragile. Once the lightning arrester fails and explodes, the splashing metal oxides and the fragile porcelain outer casing are easy to damage other electrical equipment and passers-by, and it is inconvenient to construct when installed at a high place on the line; there is no sealing design between the lightning arrester body and the chamber. Affected by the environment during long-term operation, moisture and salt stains are likely to enter the chamber under harsh climatic conditions, especially in areas with a relatively high salt fog concentration along the coast; due to no sealing treatment between the lightning arrester body and the chamber, the lightning arrester body needs to increase the insulation height and creepage umbrella skirt distance, thus increasing the weight, and the lightning arrester is easy to fall due to its own heavy weight, which also results in too high overall cost; the button-type insulating cover that is easy to be blown off by the wind cannot achieve a truly sealed and airtight full insulation. Summary of the invention:

[0005] The object of the present invention is to overcome the above-mentioned drawbacks, and aims to study a lightning arrester that can be quickly installed or disassembled integrally during live working only by means of an insulating operating rod, and can also quickly separate and repair, plug and replace the lightning arrester body during live working, and has a fixed gap setting with the function of isolating power frequency voltage, and can be directly installed on the line iron cross arm. A light insulating cavity molded from a light hard PC insulating material with high strength, high electrical performance, good explosion-proof and anti-aging properties, and greatly reduced overall weight is selected. The uppermost umbrella skirt is larger than all the lower umbrella skirts. The light insulating cavity with the design of large and small umbrellas for rain curtain and pollution prevention has a fully insulated and sealed design both above and below between its inner wall and the lightning arrester body, and will not affect the overall electrical performance of the lightning arrester operating under harsh natural conditions.

[0006] To achieve the above object, the live working fully insulated separable externally series fixed gap lightning arrester of the present invention includes: a detachable clamp 1, a drainage wire 2, a light insulating cavity 3, a metal bracket 4, an externally series fixed gap 5, a live working installation bracket 6, an upper contact 7, an upper insulating waterproof piston ring 8, a lightning arrester body 9, a contact ring 10, a lower insulating waterproof piston ring 11, a line cross arm 12, a separator 13, an insulating sheath 14, an elastic spring 15, a contact piece 16, a contact piece fixing ring 17, etc.

[0007] It is mainly applied to prevent lightning strike breakage of insulated conductors and power frequency follow current tripping in medium voltage distribution network lines. The live working installation bracket 6 and the detachable clamp 1 can be used for live working, and the separator 13 and the lightning arrester body 9 and other assemblies can be plugged and unplugged with an insulating operating rod during live working, so as to quickly repair and replace, reduce the inconvenience caused by power outage, and improve the efficiency of installation and maintenance; the application of the externally series fixed gap 5 can isolate the power frequency voltage of the system when there is no lightning strike during normal operation, and avoid the aging of the lightning arrester due to long-term live operation; it is directly installed on the cross arm 12, omitting the lightning arrester cross arm, saving costs, increasing the line corridor and improving the aesthetics.

[0008] For the live working fully insulated separable externally series fixed gap lightning arrester, the end of the drainage wire 2 is crimped to the top of the externally series gap 5, and is sealed with an insulating sheath 14 made of soft and elastic silicone rubber material. The drainage wire 2 leads the high voltage from the line to the high voltage part of the externally series gap 5. Due to the existence of the air gap, the high voltage is isolated, and the lightning arrester is not charged under normal working conditions, greatly reducing the aging rate of the lightning arrester and improving the service life.

[0009] For the live working fully insulated separable externally series fixed gap lightning arrester, the light insulating cavity 3 is of a tower structure. The cooperation of the large and small umbrella skirt structures meets the creepage distance requirements. The uppermost umbrella skirt is larger than all the lower umbrella skirts, which plays the role of preventing rain curtain and pollution and preventing the hanging ice columns from sticking to other umbrella skirts, and also has a certain role in blocking sleet and snow, making the insulation of the lightning arrester more reliable under natural disasters.

[0010] Select a light - type insulating cavity made of anti - UV grade light - type rigid PC insulating material with high strength, excellent insulation performance, good explosion - proof, anti - aging, high cost - performance, and greatly reduced overall weight. The root arcs of the large and small umbrella skirts are enhanced to cooperate with the enhanced cavity strength to play an explosion - proof role and prevent the fragments from splashing when the arrester is damaged and exploded. Once the arrester fails and explodes, the splashing metal oxides and the fragile porcelain outer sleeve are likely to cause line grounding faults, harm other electrical equipment and passers - by, and it is inconvenient to install at high places on the line.

[0011] For the live - working fully insulated separable external - series fixed - gap arrester, a lower insulating waterproof piston ring 11 is installed below the contact ring 10 for sealing, playing an insulating and sealing role to prevent the erosion of water vapor and salt mist.

[0012] The upper and lower structures of the light - type insulating cavity 3 have a certain taper to make the sealing structure with the arrester body 9 better. The structure of the light - type insulating cavity 3 that is narrow at the top and wide at the bottom makes the insertion of the arrester body 9 into the light - type insulating cavity 3 tighter and tighter. The bottom is sealed with a lower insulating waterproof piston ring 11, and an upper insulating waterproof piston ring 8 is installed on the upper part of the arrester body 9 for sealing. It is made of flexible and elastic insulating rubber material, which not only plays a sealing role but also an insulating role, preventing the high voltage at the top of the arrester body 9 from creeping electricity inside the cavity. Because the inner surface of the light - type insulating cavity 3 is smooth, the upper insulating waterproof piston ring 8 seals the inside of the cavity and the arrester body 9, and the creeping electricity will occur outside the light - type insulating cavity 3.

[0013] The drain wire 2 and the high - voltage line are installed live using a detachable clamp 1. The terminal of the drain wire 2 is screwed to the detachable clamp 1. The operating rod can be used for live - working and sleeved on the ring - shaped bolt. The detachable clamp 1 has a convenient bayonet for tightening on the high - voltage wire. The wire does not need to be peeled, and the installation is simple.

[0014] The low - voltage end of the external - series fixed - gap 5 passes through the hole on the upper surface of the light - type insulating cavity 3 and is sealed and screwed, with a sealing ring in the middle for sealing treatment to prevent the invasion of wind, rain and moisture. The air gap between the high - voltage and low - voltage electrodes of the external - series fixed - gap 5 is set at 45 ± 5 mm to ensure that the air gap can be broken down when struck by lightning, and the gap plays a role in isolating the power - frequency voltage in the system during normal operation.

[0015] Two holes are opened on the side of the contact ring 10 made of metal material with good electrical conductivity and are screwed together with the separator 13. When the separator 13 is plugged and unplugged and replaced, the contact ring is driven to be plugged and unplugged and replaced together.

[0016] The contact piece fixing ring 17 is made of a metal material with good conductivity, and screw holes are evenly distributed on the bottom to fix the contact piece 16. The contact piece 16 made of a metal material with good conductivity and good elasticity is in close, elastic and constant electrical contact with the contact ring 10 to ensure normal electrical current. Screw holes are provided on the side and are screwed to the metal bracket 4 to ensure normal electrical current.

[0017] The elastic tension spring 15 is wrapped around the contact piece 16 to tighten it, so as to prevent the contact piece from losing its elasticity and becoming loose due to a long period of time.

[0018] The outer diameter of the lower end of the arrester body 9 is closely matched with the inner wall of the contact ring 10, and the metal electrode at the bottom of the arrester body 9 is in close electrical contact with the end of the contact ring 10 through screw connection. The bottom end of the arrester body 9 is conical, and the softness of the silicone rubber jacket is used to make the connection more compact and firm, and the screw connection is closely matched accordingly. The contact ring 10 and the separator 13 are connected as a whole through a conical tightening sealing structure. The separator 13 is made of high-strength UV-resistant PC insulating material; the lower part of the separator is conically guided, and the waist is provided with a symmetrical cylindrical plug-in and pull-out operation lock. The lower end of the contact ring 10 and the separator 13 are tightly sealed with the lower insulating waterproof piston ring 11. When the arrester body assembly is inserted, the lower insulating waterproof piston ring 11 is driven. Soft and elastic rubber products are used, and its outer edge and the inner wall of the light insulating cavity 3 are waterproof and airtight, and the insulating seal is dynamic fit, which plays a sealing role to prevent the erosion of water vapor and salt mist. The light insulating cavity 3 is injection molded with UV-resistant PC hard insulating material. The root arc of the umbrella skirt is excessively enhanced, and the operating locks on both sides of the separator 13 are convenient for operating the operating lever.

[0019] The lightweight insulating cavity 3 is molded from lightweight hard UV-resistant PC insulating material with excellent electrical properties, good explosion-proof and aging resistance, which greatly reduces the overall weight. The inner surface is smooth; the outer surface of the arrester body 9 is smooth and has no umbrella skirt. The creepage distance of the arrester is carried out from the outside of the lightweight insulating cavity 3, and the internal insulation distance is sufficient.

[0020] A sealing ring is provided between the metal bracket 4 and the contact piece fixing ring 17, which are screwed together to seal the interior of the light insulating cavity 3. The contact piece fixing ring 17, the light insulating cavity 3 and the metal bracket 4 are screwed together as a whole. The electrical properties are connected, so that the current flowing through the lightning arrester can flow through the contact piece fixing ring 17 to the metal bracket 4 to the grounding terminal.

[0021] The metal bracket 4 and the live mounting bracket 6 are screwed together as a whole to ensure a stable electrical connection.

[0022] At the upper end of the arrester body 9, an upper insulating waterproof piston 8 is installed. The waterproof piston ring is equipped with two sealing rings. The upper insulating waterproof piston 8 is rigid and serves to tighten the inner wall of the cavity. The sealing rings serve to block water vapor and salt stains. Between the lower end of the contact ring 10 and the separator 13, a lower insulating waterproof piston ring 11 is tightly installed in a sealed manner to block water vapor and salt stains, creating a sealed environment inside the light insulating cavity 3. Brief Description of the Drawings:

[0023] Figure 1 It is a structural diagram of the live working fully insulated separable externally series fixed-gap arrester of the present invention.

[0024] Figure 2 It is a structural diagram of the arrester body, upper and lower insulating waterproof piston rings, contact ring, and upper contact of the present invention.

[0025] Figure 3 It is a structural diagram of the live installation bracket of the present invention. Detailed Embodiment:

[0026] The live working fully insulated separable externally series fixed-gap arrester of the present invention includes: detachable wire clamps 1, drain wires 2, light insulating cavities 3, metal brackets 4, externally series fixed gaps 5, live installation brackets 6, upper contacts 7, upper insulating waterproof piston rings 8, arrester bodies 9, contact rings 10, lower insulating waterproof piston rings 11, line cross arms 12, separators 13, insulating sheaths 14, elastic tension springs 15, contact pieces 16, contact piece fixing rings 17, etc.

[0027] The arrester body 9 is inserted into the light insulating cavity 3. The externally series fixed gap 5 is screwed onto the top of the light insulating cavity 3. The metal bracket 4 is screwed onto the live working installation bracket 6. One end of the drain wire 2 is screwed onto the externally series fixed gap 5, and the other end is screwed onto the detachable wire clamp 1, thus assembling a set of live working fully insulated separable externally series fixed-gap arresters. During installation, first insert an insulating operating rod into the operation locks on both sides of the separator 13 to lift the entire arrester, attach the live working installation bracket 6 to the existing line cross arm 12, and use another operating rod to extend into the annular screw hole 6.1 on the live working installation bracket 6 and tighten it. Then use the insulating operating rod to install the detachable wire clamp 1 on the transmission line.

[0028] When the line is struck by lightning, the lightning current passes through the detachable wire clamp 1 to the drain wire 2. The lightning current travels along the drain wire 2 to the high-voltage arcing rod part of the fixed-gap insulator, breaks down the air gap, flows to the low-voltage arcing rod, and then reaches the arrester body 9. Under high voltage, the arrester body 9 made of zinc oxide material is in a low-resistance state. The lightning current is conducted to the ground wire through the metal bracket 4 and the live working installation bracket 6. After the lightning current is discharged to the ground, the arrester body 9 returns to a high-resistance state.

[0029] When the arrester is damaged, the arrester body 9 is pulled out by clamping the operating locks on both sides of the separator 13 with an insulating operating rod, and then the arrester body 9 is replaced with a new one with the operating rod to continue operation. Due to the existence of the external series fixed gap 5, the arrester body 9 can be directly plugged in and out without hanging the ground wire when it is pulled out. The arrester on the traditional line can only be replaced after power failure, or replaced by a boom truck, which consumes a lot of time and manpower and material resources. During the damage maintenance period, the arrester cannot protect the line, and power failure will cause certain economic losses, so live working is particularly important.

[0030] Power supply reliability has become an assessment indicator for power companies. Live working on long-distance lines in mountainous areas or densely populated paddy fields has always been a technical challenge. How to effectively reduce the number of power outages and reduce labor intensity? Live working fully insulated detachable external series fixed gap lightning arresters can be used for live working during the initial installation. The line insulation level is improved, and the lightning arrester nodes can be fully insulated. The use of live working mounting bracket 6 makes the live working fully insulated detachable external series fixed gap lightning arrester more stable and reliable, especially the bending and clamping design at 6.5 of the live working mounting bracket 6 can make the bracket more stable in the horizontal direction to avoid slipping.

[0031] The top of the lightweight insulating cavity 3 is an electrical connection point. The lightweight insulating cavity 3 is made of excellent PC material, which has excellent electrical insulation performance, high mechanical strength, excellent explosion-proof performance, good waterproof and stain-resistant performance, and an insulating engineering material that greatly reduces the overall weight. Once an old lightning arrester fails and explodes, the splashing metal oxides together with the fragile porcelain jacket can easily cause a line grounding fault, harming other electrical equipment and passers-by. It is inconvenient to install it at a high place on the line.

[0032] According to national standards, the design of the arrester shed is a structure in which the top is larger and the bottom is smaller. The light insulating cavity 3 is designed so that the top shed is the largest, which can provide good protection for the sheds below. Tests have shown that the first shed is the largest, which can better prevent surface flashover, especially for blocking electrical channels formed by rain curtains, icicles, and snow.

[0033] The light insulating cavity 3 is made of hard high-strength PC material, which can prevent birds from tearing and pecking at it. Especially in recent years, the environment has improved and the number of birds has increased, which has caused certain damage to the operation of the line.

[0034] The purpose of this design is as follows: to reduce weight and enhance explosion-proof performance; to improve the insulation level of the circuit; to enable rapid live working, and the installation, disassembly, repair and replacement of the product do not require climbing poles and can be completed on the ground with the help of an insulating operating rod, reducing labor intensity and improving the safety of operation and maintenance; because the power frequency voltage of the system is isolated, the aging of the arrester body 9 caused by the system voltage is avoided, and at the same time, the arrester body 9 and the whole can be installed and disassembled without hanging a grounding wire. The arrester body 9 is installed in the light insulating cavity 3 to avoid the invasion of sunlight, rain and haze, making the arrester more stable and having a longer service life.

Claims

1. A fully insulated separable external series fixed-gap lightning arrester device for live working, comprising: It consists of a detachable clamp (1), a bypass wire (2), a lightweight insulating cavity (3), a metal bracket (4), an externally series fixed gap (5), a live working installation bracket (6), an upper contact (7), an upper insulating waterproof piston ring (8), a lightning arrester body (9), a contact ring (10), a lower insulating waterproof piston ring (11), a line cross arm (12), a separator (13), an insulating sheath (14), a resilient spring (15), a contact piece (16), and a contact piece fixing ring (17). The bypass wire (2) is screwed to the detachable clamp (1); the bypass wire (2) is crimped to the top of the externally series fixed gap (5), and the insulating sheath (14) is used for sealing; the externally series fixed gap (5) is screwed to the top of the lightweight insulating cavity (3) as a whole, with a sealing ring padded in between; the metal bracket (4) hugs the lightweight insulating cavity (3), and bolts pass through the lightweight insulating cavity (3) and the contact piece fixing ring (17) and are screwed together to ensure sufficient electrical connection; the bottom electrode of the lightning arrester body (9) presses on the end face of the contact ring (10) to form electrical contact, and screw holes are distributed on the side of the contact ring (10) and are screwed and fixed to the separator (13); screw holes are distributed at the bottom end of the contact piece fixing ring (17) for fixing the contact piece (16), and screw holes are provided on the side and are screwed to the metal bracket (4); the contact piece (16) makes close elastic electrical contact with the contact ring (10); the metal bracket (4) and the live working installation bracket (6) are screwed together as a whole between two holes; the live working installation bracket (6) is hung on the original iron cross arm (12) of the line; the separator (13) is screwed to the conical bottom of the lightning arrester body (9) and fits tightly; the lower part of the separator is conically guided, and symmetric cylindrical plugging and unplugging operation latches are provided at the waist, and it can be plugged and replaced quickly after being clamped. During installation, first insert an insulating operating rod into the operating latches on both sides of the separator (13) to lift the entire lightning arrester, install the live working installation bracket (6) on the existing cross arm (12) of the line, and then use the insulating operating rod to install the detachable clamp (1) on the transmission line. After the lightning arrester is damaged, use the insulating operating rod to clamp the operating latches on both sides of the separator (13) to pull out the lightning arrester body (9), and then use the operating rod to replace it with a new lightning arrester body (9) and continue to operate.

2. The live working fully insulated separable external series fixed gap lightning arrester device according to claim 1, characterized in that: The lightweight insulating cavity (3) is of a tower type structure, and the combination of large and small umbrella skirt structures meets the creepage distance requirements. The upper umbrella skirt is larger than the next umbrella skirt, then larger and smaller, and the topmost umbrella skirt is larger than all the umbrella skirts below; there is a taper of more than half a degree between the upper and lower inner walls of the cavity.

3. The live working fully-insulated separable external series fixed-gap lightning arrester device according to claim 1, characterized in that: An upper insulating waterproof piston ring (8) is installed at the upper end of the lightning arrester body (9), and two sealing rings are installed on the waterproof piston ring. A lower insulating waterproof piston ring (11) is installed at the lower part of the contact ring (10).

4. The live working fully-insulated separable external series fixed-gap lightning arrester device according to claim 1, characterized in that: For the live working installation bracket (6), a ring-shaped bolt (6.1) is used to tightly press against the iron cross arm (12), and a spring washer is provided at the top (6.4) of the ring-shaped bolt (6.1).

5. The live working fully-insulated separable external series fixed-gap lightning arrester device according to claim 1, characterized in that: The separator (13) is made of a high-strength ultraviolet-resistant insulating material.

6. The live working fully insulated separable external series fixed gap lightning arrester device according to claim 1, characterized in that: The lightweight insulating cavity (3) is injection molded from an anti-UV grade PC rigid insulating material, and the root arc of the umbrella skirt is transitioned to improve strength.

7. The live working fully-insulated separable external series fixed-gap lightning arrester device according to claim 1, characterized in that: The resilient spring (15) is strapped on the contact piece (16).

8. The live working fully-insulated separable external series fixed-gap lightning arrester device according to claim 1, characterized in that: The outer surface of the arrester body (9) is smooth.

9. The live working fully insulated separable external series fixed gap lightning arrester device according to claim 1, characterized in that: The air gap between the high-voltage and low-voltage electrodes of the external series fixed gap (5) is set at 45 ± 5 mm.

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