Extra-high voltage icing flashover prevention composite insulator

Abstract

The invention relates to the technical field of insulators, and discloses an extra-high voltage icing flashover prevention composite insulator which comprises a core rod, a first umbrella skirt, a second umbrella skirt, a third umbrella skirt and connecting fittings, the first umbrella skirt, the second umbrella skirt and the third umbrella skirt are distributed at intervals in the axial direction of the core rod, and the connecting fittings are arranged at the two ends of the core rod; the radial size of the first umbrella skirt is larger than that of the second umbrella skirt, the radial size of the second umbrella skirt is larger than that of the third umbrella skirt, one first umbrella skirt, at least one second umbrella skirt and at least one third umbrella skirt form an umbrella skirt group, and the first umbrella skirt is located at the upper part of the umbrella skirt group; the first umbrella skirt is provided with a bulged surface with a high middle and a low periphery, the bulged surface is convexly provided with a plurality of diversion ribs, each diversion rib is provided with a first end and a second end, and the diversion ribs are arranged obliquely to the radial direction of the first umbrella skirt; the projections of the plurality of diversion ribs of two adjacent first umbrella skirts in the radial cross section are distributed at intervals in the circumferential direction. Water can be quickly drained, icing is reduced, ice ridge bridging is inhibited, and the device is suitable for extra-high voltage re-icing scenes.

Description

Technical Field

[0001] The present invention relates to the technical field of insulators, and in particular to an ultra-high voltage ice-flash protection composite insulator. Background Art

[0002] In power systems, high-voltage overhead lines are equipped with insulators to connect supporting conductors to transmission towers and isolate currents caused by potential differences. Insulators are primarily classified by insulation material into porcelain, glass, and composite insulators.

[0003] Currently, transmission lines in heavily icing areas mostly use disc-type porcelain or glass insulators, which require frequent cleaning and zero-value testing, resulting in high operation and maintenance costs and insufficient ice flashover resistance. Existing composite insulators are widely used in areas with light and moderate icing. Composite insulators consist of a core rod, sheds, and hardware. The core rod is made of glass fiber-reinforced epoxy resin to stably withstand mechanical loads, while the sheds are made of materials such as silicone rubber to provide insulation and flashover protection. However, composite insulators still have the following problems: 1. They are vulnerable to dynamic impacts caused by deicing. The instantaneous impact generated by the shedding of ice can cause mechanical damage to the insulators. 2. The ice flashover voltage is low, and ice bridging the sheds can easily cause flashover accidents. 3. The shed shape has poor adaptability. Conventional sheds have difficulty delaying ice ridge bridging, and their resistance to contaminated icing is insufficient.

[0004] In summary, existing composite insulators used in UHV transmission lines in heavy icing areas have poor ice flash resistance and a high damage rate due to ice shedding impact, and cannot simultaneously meet the mechanical and electrical performance requirements in heavy icing areas. Summary of the Invention

[0005] The technical problem to be solved by the present invention is that the existing composite insulators used in ultra-high voltage transmission lines in heavy ice areas have poor ice flash resistance and high ice shedding impact damage rate, and cannot simultaneously meet the mechanical and electrical performance requirements in heavy ice areas.

[0006] In order to solve the above technical problems, the present invention provides a technical solution for an ultra-high voltage ice-flash protection composite insulator: the ultra-high voltage ice-flash protection composite insulator includes a core rod, and a first shed, a second shed, a third shed, and a connecting hardware provided on the core rod, wherein the first shed, the second shed, and the third shed are spaced apart along the axis of the core rod, and the connecting hardware is provided at both ends of the core rod; The radial dimension of the first shed is greater than that of the second shed, the radial dimension of the second shed is greater than that of the third shed, one first shed, at least one second shed, and at least one third shed constitute a shed group, and the first shed is located at the upper part of the shed group; The upper side of the first shed has a bulging surface that is higher in the middle and lower around the edges. The bulging surface is provided with a plurality of guide ribs protruding therefrom. The plurality of guide ribs are circumferentially spaced apart about the first shed. The guide ribs have a first end proximate to the middle of the first shed and a second end protruding outside the first shed. From the first end to the second end, the extension direction of the guide rib is inclined to the radial arrangement of the first shed; the projections of the multiple guide ribs of two adjacent first sheds in the radial cross section of the core rod are circumferentially spaced.

[0007] Furthermore, the projection profile of the guide rib in the radial cross section of the core rod is arc-shaped, and the angle between the tangent direction of the guide rib and the diameter direction of the core rod gradually increases from the first end to the second end.

[0008] Furthermore, the angle between the tangential direction of the guide rib and the diameter direction of the core rod is in the range of 0 to 60 degrees.

[0009] Furthermore, with the core rod as the center, a central angle between a radial direction where the first end is located and a radial direction where the second end is located is any angle between 30° and 90°.

[0010] Furthermore, with the core rod as the center, a central angle between a radial direction where the first end is located and a radial direction where the second end is located is any angle between 45° and 70°.

[0011] Furthermore, the protruding height of the guide rib relative to the bulging surface is any size between 2 mm and 6 mm, and the protruding length of the second end relative to the first umbrella skirt is any size between 3 mm and 10 mm.

[0012] Furthermore, the protruding height of the guide rib relative to the bulging surface is any size between 3mm and 4mm, and the protruding length of the second end relative to the first umbrella skirt is any size between 5mm and 7.5mm.

[0013] Furthermore, the first umbrella skirt is made of silicone rubber, and the first umbrella skirt and the plurality of guide ribs are an integrated structure.

[0014] Furthermore, the diameter of the first umbrella skirt is any size between 320 mm and 450 mm, the diameter of the second umbrella skirt is any size between 160 mm and 240 mm, and the diameter of the third umbrella skirt is any size between 120 mm and 200 mm.

[0015] Furthermore, it also includes a water diversion cover, which is separately installed on the core rod and arranged close to one of the connecting hardware. The radial size of the water diversion cover is larger than the radial size of the first umbrella skirt.

[0016] Compared to existing technologies, the UHV ice-flash protection composite insulator of the present invention offers the following advantages: It utilizes a core rod, first sheds, second sheds, third sheds, and connecting hardware. The first, second, and third sheds are spaced apart along the core rod axis, with the radial dimension of the first shed greater than that of the second shed, and greater than that of the third shed. One first shed, at least one second shed, and at least one third shed form a "large at top, small at bottom" shed group. The large first shed enhances the arc creepage distance, effectively extending the discharge path. The medium and small second and third sheds further divide the arc, increasing the flashover voltage through a stepped insulation shielding design. Furthermore, the combination of sheds of varying sizes inhibits the continuous growth of ice ridges between adjacent sheds, reducing the probability of ice flashover.

[0017] The upper side of the first shed features a raised surface, higher in the middle and lower around the edges. This surface facilitates the drainage of meltwater from ice and snow, preventing it from freezing on the surface of the first shed. Furthermore, the raised surface generates high-speed airflow in windy conditions, leveraging wind power to reduce the accumulation of snow or icy rain, further slowing the rate of ice accumulation. Circumferentially spaced guide ribs are arranged on the raised surface as reinforcements, enhancing the structural strength of the first shed and reducing the risk of damage from shedding impact. Extending radially from the first end to the second end, the guide ribs form drainage channels on the raised surface, directing and rapidly channeling meltwater or rainwater, preventing the formation of ice ridges at the edges of the first shed. The staggered projections of the guide ribs on adjacent first sheds prevent overlap between the upper and lower flow paths, achieving flow regulation and minimizing ice ridge bridging.

[0018] In addition, the inclined guide ribs can also break up the airflow boundary layer of the first shed, preventing significant water droplet aggregation and ice formation on the leeward side of the first shed, thereby improving the situation of severe icing on one side of the shed. At the same time, because the second end of the guide rib protrudes from the outer surface of the first shed, the tip effect can disperse the local electric field to suppress arc initiation and development. Through the coordinated design of the gradient shed, bulged surface, and guide ribs, water can be quickly drained, ice accumulation can be reduced, and ice bridging can be suppressed, significantly improving the flashover voltage of the insulator in UHV environments. It is suitable for UHV heavy icing scenarios, improving insulation reliability, reducing operation and maintenance costs, and meeting the mechanical and electrical performance requirements of heavy icing areas. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 12. It is a schematic diagram of the main view of the ultra-high voltage ice-flash protection composite insulator according to an embodiment of the present invention; Figure 2 is a partial cross-sectional view of an ultra-high voltage ice-flash protection composite insulator according to an embodiment of the present invention; Figure 3 1 is a schematic top view of the first shed in an embodiment of the present invention; In the figure: 1. core rod; 11. first shed; 110. bulging surface; 111. guide rib; 112. first end; 113. second end; 12. second shed; 13. third shed; 2. connecting hardware; 3. shed assembly; 4. water-dividing cover. DETAILED DESCRIPTION

[0020] The following embodiments of the present invention are described in further detail with reference to the accompanying drawings and examples. The following examples are used to illustrate the present invention but are not intended to limit the scope of the present invention.

[0021] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like used in the present invention to indicate the orientation or position relationship are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention.

[0022] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature identified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0023] In the present invention, unless otherwise expressly specified or limited, terms such as "mounted," "connected," "connect," and "fixed" should be understood broadly. For example, they may refer to fixed connection, detachable connection, or integration; they may refer to direct connection or indirect connection through an intermediate medium; they may refer to internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0024] like Figures 1 to 3As shown, an ultra-high voltage ice-flash protection composite insulator according to an embodiment of the present invention includes a core rod 1, and a first shed 11, a second shed 12, a third shed 13 and a connecting hardware 2 arranged on the core rod 1. The first shed 11, the second shed 12 and the third shed 13 are spaced apart along the axial direction of the core rod 1, and the connecting hardware 2 is arranged at both ends of the core rod 1; the radial dimension of the first shed 11 is greater than the radial dimension of the second shed 12, and the radial dimension of the second shed 12 is greater than the radial dimension of the third shed 13. One first shed 11, at least one second shed 12 and at least one third shed 13 constitute an shed group 3, and the first shed 11 is located at the upper part of the shed group 3.

[0025] The upper side of the first shed 11 has a bulging surface 110 that is higher in the middle and lower on all sides. The bulging surface 110 is protruding with multiple guide ribs 111, and the multiple guide ribs 111 are circumferentially spaced about the first shed 11; the guide rib 111 has a first end 112 close to the middle of the first shed 11, and a second end 113 protruding from the outside of the first shed 11; from the first end 112 to the second end 113, the extension direction of the guide rib 111 is inclined to the radial arrangement of the first shed 11; the projections of the multiple guide ribs 111 of two adjacent first sheds 11 in the radial cross section of the core rod 1 are circumferentially spaced.

[0026] This ultra-high voltage ice-flash protection composite insulator features a core rod 1, first sheds 11, second sheds 12, third sheds 13, and connecting hardware 2. The first sheds 11, second sheds 12, and third sheds 13 are spaced apart along the axis of the core rod 1. The radial dimension of the first shed 11 is greater than that of the second shed 12, which is greater than that of the third shed 13. One first shed 11, at least one second shed 12, and at least one third shed 13 form a shed group 3 with larger top and smaller bottom sections. The large first shed 11 increases the arc creepage distance and effectively extends the discharge path. The medium and small second sheds 12 and third sheds 13 further divide the arc, increasing the flashover voltage through a stepped insulation shielding design. Furthermore, the combined arrangement of sheds of different sizes in the group 3 inhibits the continuous growth of ice ridges between adjacent sheds, reducing the probability of ice flashover.

[0027] The upper side of the first shed 11 features a raised surface 110, which is higher in the middle and lower around the edges. This surface facilitates the drainage of meltwater from ice and snow, preventing it from freezing on the surface of the first shed 11. Furthermore, in windy conditions, the raised surface 110 generates high-speed airflow, leveraging wind power to reduce the accumulation of snow or icy rain, further slowing the rate of ice accumulation. Guide ribs 111 are spaced circumferentially along the raised surface 110. These ribs serve as reinforcements, enhancing the structural strength of the first shed 11 and reducing damage from deicing impacts. Extending radially from a first end 112 to a second end 113, the guide ribs 111 form drainage channels on the raised surface 110, directing meltwater or rainwater in a targeted and rapid manner, preventing the formation of ice ridges at the edges of the first shed 11. The staggered projections of the guide ribs 111 on adjacent first sheds 11 prevent overlap between the upper and lower water paths, achieving flow regulation and minimizing ice ridge bridging.

[0028] In addition, the obliquely extended guide ribs 111 can also break the airflow boundary layer of the first shed 11, preventing significant water droplet aggregation and ice formation on the leeward side of the first shed 11, thereby improving the situation of severe icing on one side of the shed. At the same time, because the second end 113 of the guide rib 111 protrudes from the surface of the first shed 11 on the outside of the first shed 11, the tip effect can disperse the local electric field to suppress arc initiation and development. Through the coordinated design of the gradient shed, the bulged surface 110 and the guide rib 111, water can be quickly drained, ice accumulation can be reduced, and ice bridging can be suppressed, significantly improving the flashover voltage of the insulator in UHV environments. It is suitable for UHV heavy icing scenarios, improving insulation reliability, reducing operation and maintenance costs, and meeting the mechanical and electrical performance requirements of heavy icing areas.

[0029] In this embodiment, the projection profile of the guide rib 111 in the radial cross section of the core rod 1 is arc-shaped. From the first end 112 to the second end 113, the angle between the tangent direction of the guide rib 111 and the diameter direction of the core rod 1 gradually increases. The tangent angle α of the guide rib 111 at the first end 112 is small, which is more conducive to converting gravity into a component force for draining water droplets outward. Specifically, Figure 3 The angle α between the tangent direction of the guide rib 111 and the diameter direction of the mandrel 1 is within a range of 15° to 45°. To meet different usage requirements, in other embodiments, the angle between the tangent direction of the guide rib and the diameter direction of the mandrel is within any other range of 0° to 60°.

[0030] Furthermore, with the core rod 1 as the center, the central angle between the radial direction of the first end 112 and the radial direction of the second end 113 is anywhere between 30° and 90°. As a further preferred embodiment, the first shed 11 is provided with four guide ribs 111, which are evenly spaced circumferentially. With the core rod 1 as the center, the central angle between the radial direction of the first end 112 and the radial direction of the second end 113 is anywhere between 45° and 70°. The guide ribs 111 effectively cover the central angle range of the first shed 11, ensuring that the guide ribs 111 provide reliable directional drainage for water droplets flowing outward from the bulge surface 110.

[0031] It should be noted that the protruding height of the guide rib 111 relative to the bulged surface 110 is any dimension between 2mm and 6mm, and the protruding length of the second end 113 relative to the first shed 11 is any dimension between 3mm and 10mm. In this embodiment, the protruding height of the guide rib 111 relative to the bulged surface 110 is any dimension between 3mm and 4mm, and the protruding length of the second end 113 relative to the first shed 11 is any dimension between 5mm and 7.5mm. The moderate protruding height of the guide rib 111 can stably guide meltwater and rainwater from the bulged surface 110. The second end 113, as an extension of the guide rib 111, allows the meltwater to drip and drain away from the first shed 11, reducing the problem of ice bridging.

[0032] The first shed 11 is made of silicone rubber and is integrally formed with the plurality of guide ribs 111, ensuring the structural strength and impact resistance of the first shed 11. Furthermore, the diameter of the first shed 11 can be any size between 320 mm and 450 mm, the diameter of the second shed 12 can be any size between 160 mm and 240 mm, and the diameter of the third shed 13 can be any size between 120 mm and 200 mm.

[0033] In addition, the UHV anti-ice-flash composite insulator also includes a water diverter hood 4, which is separately installed on the core rod 1 and arranged near one of the connecting hardware 2. The radial dimension of the water diverter hood 4 is larger than the radial dimension of the first shed 11. The rainwater discharged from the upper shed can be dispersed through the water diverter hood 4, thereby improving the anti-ice-flash performance of the entire composite insulator.

[0034] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. A UHV anti-ice flash composite insulator, characterized by: The invention comprises a core rod, and first, second, and third sheds provided on the core rod, and connecting hardware, wherein the first, second, and third sheds are spaced apart along the axis of the core rod, and the connecting hardware is provided at both ends of the core rod; The radial dimension of the first shed is greater than that of the second shed, the radial dimension of the second shed is greater than that of the third shed, one first shed, at least one second shed, and at least one third shed constitute a shed group, and the first shed is located at the upper part of the shed group; The upper side of the first shed has a bulging surface that is higher in the middle and lower around the edges. The bulging surface is provided with a plurality of guide ribs protruding therefrom. The plurality of guide ribs are circumferentially spaced apart about the first shed. The guide ribs have a first end proximate to the middle of the first shed and a second end protruding outside the first shed. From the first end to the second end, the extension direction of the guide rib is inclined to the radial arrangement of the first shed; the projections of the multiple guide ribs of two adjacent first sheds in the radial cross section of the core rod are circumferentially spaced.

2. The ultra-high voltage ice-flash protection composite insulator according to claim 1 is characterized in that: The projection profile of the guide rib in the radial cross section of the core rod is arc-shaped, and the angle between the tangent direction of the guide rib and the diameter direction of the core rod gradually increases from the first end to the second end.

3. The UHV ice-flash protection composite insulator according to claim 2 is characterized in that: The angle between the tangent direction of the guide rib and the diameter direction of the core rod is within the range of 0 to 60 degrees.

4. The UHV ice-flash protection composite insulator according to claim 3 is characterized in that: With the core rod as the center, a central angle between a radial direction where the first end is located and a radial direction where the second end is located is any angle between 30° and 90°.

5. The UHV ice-flash protection composite insulator according to claim 3 is characterized in that: With the core rod as the center, a central angle between a radial direction where the first end is located and a radial direction where the second end is located is any angle between 45° and 70°.

6. The UHV ice-flash protection composite insulator according to any one of claims 1 to 5, characterized in that: The protruding height of the guide rib relative to the bulging surface is any size between 2mm and 6mm, and the protruding length of the second end relative to the first umbrella skirt is any size between 3mm and 10mm.

7. The ultra-high voltage ice-flash protection composite insulator according to any one of claims 1 to 5, characterized in that: The protruding height of the guide rib relative to the bulging surface is any size between 3mm and 4mm, and the protruding length of the second end relative to the first umbrella skirt is any size between 5mm and 7.5mm.

8. The UHV ice-flash protection composite insulator according to claim 1 is characterized in that: The first umbrella skirt is made of silicone rubber, and the first umbrella skirt and the plurality of guide ribs are an integrated structure.

9. The UHV ice-flash protection composite insulator according to claim 1 is characterized in that: The diameter of the first umbrella skirt is any size between 320mm and 450mm, the diameter of the second umbrella skirt is any size between 160mm and 240mm, and the diameter of the third umbrella skirt is any size between 120mm and 200mm.

10. The ultra-high voltage ice-flash protection composite insulator according to claim 1 is characterized in that: It also includes a water diversion cover, which is separately installed on the core rod and arranged close to one of the connecting hardware. The radial size of the water diversion cover is larger than the radial size of the first umbrella skirt.

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