Lightning protection grounding structure of wind turbine generator
By drilling holes around the wind turbine foundation, filling them with graphene material, and using hot-dip galvanized steel pipes as vertical grounding electrodes, combined with a horizontal grounding grid, the problem of high grounding resistance in high resistivity rock geology was solved, achieving low-cost and efficient grounding, ensuring equipment safety and construction benefits.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-30
- Publication Date
- 2026-04-07
AI Technical Summary
Traditional wind turbine lightning protection grounding structures have difficulty reducing grounding resistance in rocky soils with high resistivity, leading to equipment damage and safety threats, and are also difficult and costly to construct.
Grounding boreholes are drilled around the wind turbine foundation, penetrating from high-resistivity rock layers to low-resistivity strata. Graphene material is filled in to form a conductive transition body, and hot-dip galvanized steel pipes are used as vertical grounding electrodes. Combined with a horizontal grounding grid and equipotential rings, the current distribution is optimized.
It effectively reduces grounding resistance, ensures safe equipment operation, reduces construction workload and costs, reduces material consumption, and improves construction efficiency.
Smart Images
Figure CN224093498U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the field of wind turbine foundation grounding construction, and particularly relates to a wind turbine lightning protection grounding structure. BACKGROUND
[0002] With the development of energy construction concepts such as economy, energy saving and emission reduction, large power stations, wind turbines and the like are often located in high-altitude mountains, hills and the like. There are a large number of rock geological structures in these terrains, and the soil resistivity is high, which makes it difficult to meet the grounding requirements. In rainy weather, the high grounding resistance value of the grounding body can cause the large current to be not released well, resulting in damage to the wind turbine equipment and threatening the personal safety of personnel. Therefore, in order to ensure the normal operation of the equipment and the safety of personnel, a good and reliable grounding protection needs to be provided near the wind turbine foundation to reduce the grounding resistance. The traditional wind turbine is usually grounded by a vertical grounding electrode buried in the ground to a certain depth for lightning protection. The effect of reducing the grounding resistance is limited. If it is directly applied to high-resistivity rock geological soil, the grounding resistance will be difficult to reduce to the target value (such as ≤4Ω). It is often necessary to increase the number or length of the vertical grounding electrode to reduce the grounding resistance value to meet the requirements. However, due to the limitation of the rock terrain, a large amount of excavation or deep hole drilling needs to be carried out when the above-mentioned construction method is used, resulting in large overall excavation and backfill engineering quantity, high construction difficulty, and the need for a large amount of materials, which increases the construction cost and material cost. SUMMARY
[0003] The utility model aims at providing a wind turbine lightning protection grounding structure suitable for rock geological structures, which can effectively reduce the grounding resistance value of the wind turbine in the rock geological structure and reduce the construction engineering quantity and cost.
[0004] The wind turbine lightning protection grounding structure comprises a vertical grounding electrode in communication with a wind turbine foundation. A plurality of grounding drill holes corresponding to the number of vertical grounding electrodes are uniformly arranged around the wind turbine foundation in the circumferential direction. The grounding drill holes penetrate the high-resistivity rock layer and are in communication with the low-resistivity stratum, forming a high-resistivity rock layer section and a low-resistivity stratum section. The wall surface of the high-resistivity rock layer section has rock layer fissures. The vertical grounding electrode is inserted into the grounding drill hole, and the bottom end of the vertical grounding electrode is inserted into the low-resistivity stratum through the grounding drill hole. A conductive transition body formed by high-pressure filling of graphene material is arranged between the vertical grounding electrode and the high-resistivity rock layer section of the grounding drill hole and in the rock layer fissures of the high-resistivity rock layer section.
[0005] The lightning protection grounding structure for wind turbines provided by this utility model involves drilling a grounding borehole around the wind turbine foundation using a drilling rig. The depth of the borehole is adjusted according to geological exploration data, penetrating from a high-resistivity rock layer to a low-resistivity stratum. Graphene material is then high-pressure filled into the grounding borehole and vibrated to ensure full contact between the graphene and the high-resistivity rock layer section, as well as within the rock fissures of that section. A vertical grounding electrode is then inserted into the grounding borehole, with its bottom end extending through the borehole into the low-resistivity stratum. After the graphene material solidifies under high pressure, a conductive transition body is formed, which can tightly... The graphene material is densely packed between high-resistivity rock strata and within rock fissures in the grounding borehole. Due to its low resistivity, the conductive transition body formed by graphene allows the current on the vertical grounding electrode to be more smoothly introduced into the low-resistivity strata, thereby effectively reducing the total grounding resistance in the rock geological structure. This better meets the grounding requirements of the wind turbine, ensuring the normal operation of the wind turbine equipment and the personal safety of personnel. Furthermore, the construction of the above structure is simple, requiring no large-scale excavation, backfilling, or excessive material consumption, effectively reducing the amount of construction work and material costs, and demonstrating good technical and economic benefits.
[0006] Furthermore, the conductive transition body formed by the graphene material is a condensation of graphene powder or graphene slurry.
[0007] Furthermore, the vertical grounding electrode is a hot-dip galvanized steel pipe.
[0008] Furthermore, it also includes a horizontal grounding grid with a closed ring structure, wherein the vertical grounding electrode is connected to the horizontal grounding grid, and a connecting conductor that connects the horizontal grounding grid to the wind turbine foundation is uniformly arranged along the circumference of the horizontal grounding grid.
[0009] Furthermore, the horizontal grounding grid includes an inner grounding grid and an outer grounding grid. Both the inner and outer grounding grids are closed ring structures and are concentrically arranged. The ring structure diameter of the outer grounding grid is larger than that of the inner grounding grid. The vertical grounding electrode is connected to the outer grounding grid, and the inner and outer grounding grids are connected by a connecting conductor.
[0010] Furthermore, it also includes an equalizing ring installed on the wind turbine foundation, which is connected to the outer grounding grid via a grounding lead.
[0011] Furthermore, multiple grounding modules are spaced apart on the horizontal grounding grid. Attached Figure Description
[0012] Figure 1 This is a grounding schematic diagram of the vertical grounding electrode of this utility model.
[0013] Figure 2 This is a schematic diagram of the connection structure of this utility model.
[0014] Figure 3 for Figure 2 A schematic diagram of AA in the diagram.
[0015] In the diagram: 1-Wind turbine foundation; 2-Grounding borehole; 3-Vertical grounding electrode; 4-Outer grounding grid; 5-Inner grounding grid; 6-Connecting conductor; 7-Equalizing ring; 8-Grounding lead; 9-Conductive transition body; 10-High-resistivity rock stratum; 20-Low-resistivity stratum. Detailed Implementation
[0016] The technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. Based on the embodiments of this utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of this utility model.
[0017] It should be noted that if any directional indication (such as up, down, left, right, front, back, top, bottom, inside, outside, vertical, horizontal, longitudinal, counterclockwise, clockwise, circumferential, radial, axial, etc.) is involved in the embodiments of this utility model, the directional indication is only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.
[0018] If the embodiments of this utility model involve descriptions such as "first" or "second," such descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined with "first" or "second" may explicitly or implicitly include at least one of those features. Furthermore, the technical features of each embodiment can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the embodiments are described; however, as long as these combinations of technical features do not contradict each other, they should all be considered within the scope of this specification.
[0019] This embodiment provides a lightning protection grounding structure for wind turbines suitable for rock geological structures.
[0020] like Figures 1 to 3As shown, the lightning protection grounding structure of the wind turbine includes a vertical grounding electrode 3 connected to the wind turbine foundation 1; grounding boreholes 2 are uniformly arranged around the wind turbine foundation 1 along the circumference, corresponding to the number of vertical grounding electrodes 3. The grounding boreholes 2 penetrate the high-resistivity rock layer and connect with the low-resistivity stratum, forming a high-resistivity rock layer section 10 and a low-resistivity stratum section 20. The wall of the high-resistivity rock layer section 10 has rock fissures. The vertical grounding electrode 3 is inserted into the grounding borehole 2, and its bottom end passes through the grounding borehole 2 and is inserted into the low-resistivity stratum. A conductive transition body 9 formed of graphene material is also high-pressure filled between the vertical grounding electrode 3 and the high-resistivity rock layer section of the grounding borehole and in the rock fissures of the high-resistivity rock layer section.
[0021] When implementing this technical solution, firstly, grounding boreholes 2 are drilled around the wind turbine foundation 1 using a drilling rig. Each grounding borehole 2 is evenly arranged around the wind turbine foundation 1, and the spacing between adjacent grounding boreholes 2 can be determined based on the soil resistivity gradient, typically set to 5m to 10m. The diameter of the grounding borehole 2 can be specifically set to 150mm, and the depth of the grounding borehole 2 is adjusted according to geological exploration data, ranging from 10m to 50m, ensuring that the grounding borehole 2 can penetrate from a high-resistivity rock layer to a low-resistivity stratum. Subsequently, graphene material, such as graphene powder or graphene slurry, is high-pressure filled into the grounding borehole 2 and vibrated to ensure sufficient and tight contact between the graphene material and the high-resistivity rock layer section in the grounding borehole, as well as within the rock fissures of the high-resistivity rock layer section. Finally, a vertical grounding electrode 3 is inserted into the grounding borehole. In section 2, the bottom end of the vertical grounding electrode 3 passes through the grounding borehole 2 and is inserted into the low-resistivity stratum. After the graphene material is solidified under high pressure, a conductive transition body 9 is formed. The conductive transition body 9 can tightly fill the high-resistivity rock strata and rock fissures in the grounding borehole. Since the graphene material has low resistivity and good conductivity, the conductive transition body 9 formed by the graphene material can allow the current on the vertical grounding electrode 3 to be smoothly introduced into the low-resistivity stratum, thereby effectively reducing the total grounding resistance value in the rock geological structure, so as to better meet the grounding requirements of the wind turbine, ensure the normal operation of the wind turbine equipment and the personal safety of personnel. Moreover, the above structure has low construction difficulty, does not require large-scale excavation, backfilling, etc., and does not consume too much material, which can effectively reduce the amount of construction work and material costs, and has good technical and economic benefits.
[0022] Specifically, in this embodiment, the conductive transition body 9 formed by graphene material can be graphene powder or a condensed form of graphene slurry. The graphene slurry ratio can be set to a graphene content ≥60%, a viscosity of 2000~3000 cP, and an injection pressure of 0.5~1.2 MPa, ensuring it is fully and tightly filled into the rock fissures of the high-resistivity rock layer. The conductive transition body 9 formed after solidification can improve the resistivity of the surrounding soil. Furthermore, in this embodiment, the vertical grounding electrode is specifically a DN50mm hot-dip galvanized steel pipe, which has low resistivity, better guides current, and allows current to flow more smoothly in the grounding electrode, reducing interference with wind turbine equipment and energy loss. It is also easy to install, and the galvanized structure makes it more corrosion-resistant, extending its service life.
[0023] The aforementioned lightning protection grounding structure may further include a horizontal grounding grid in a closed ring structure. The vertical grounding electrode 3 is connected to the horizontal grounding grid, and a connecting conductor 6, which connects the horizontal grounding grid to the wind turbine foundation 1, is also uniformly arranged circumferentially on the horizontal grounding grid. The ring-shaped horizontal grounding grid, in conjunction with the vertical grounding electrode structure, allows the current to be distributed relatively evenly within the circumference of the horizontal grounding grid before flowing into the earth through the vertical grounding electrode. This facilitates current diffusion and radiation, further reducing grounding resistance and ensuring compliance with grounding requirements. Furthermore, the horizontal grounding grid can shield against electromagnetic interference, protecting electronic equipment from interference. The specific structure, burial depth, and number of horizontal grounding grids can be adjusted according to the actual resistivity of the soil. Specifically, for example... Figure 1 As shown, the horizontal grounding grid includes an inner grounding grid 5 and an outer grounding grid 4. Both the inner and outer grounding grids are closed ring structures and are concentrically arranged. The diameter of the ring structure of the outer grounding grid 4 is larger than that of the ring structure of the inner grounding grid 5. The vertical grounding electrode 3 is connected to the outer grounding grid 4, and the inner and outer grounding grids are connected by a connecting conductor 6. By setting the horizontal grounding grid as a layered covering structure, the current distribution can be further optimized and local high resistance defects can be compensated, making it suitable for complex rock geological structures without using excessive materials or occupying too much space. Specifically, in this embodiment, the distance between the inner grounding grid 5 and the center of the wind turbine foundation is 13m, and the distance between the outer grounding grid 4 and the center of the wind turbine foundation is 18~30m. Each grounding grid uses 60×6mm hot-dip galvanized flat steel.
[0024] The lightning protection grounding structure also includes an equipotential ring 7 installed on the wind turbine foundation 1. The equipotential ring 7 is connected to the outer grounding grid 4 via grounding leads 8. The equipotential ring 7 ensures that the wind turbine is at the same potential when struck by lightning, and transmits the lightning current to the outer grounding grid 4 through the equipotential ring 7. Finally, the lightning current is introduced into the earth through the vertical grounding electrode 3 connected to the outer grounding grid 4. In addition, multiple grounding modules (not shown in the figure) are spaced apart on the horizontal grounding grid. These grounding modules can be non-metallic grounding modules, such as the YT002-Y type. As excellent artificial grounding bodies, they are particularly suitable for use in areas with high soil resistivity. Using them as auxiliary grounding bodies enhances current diffusion, allowing the current to be better transmitted to the earth, and helps save construction costs. Specifically, the grounding modules can be installed on the horizontal grounding grid at 3m intervals.
[0025] The above description is only a preferred embodiment of the present utility model and does not limit the patent scope of the present utility model. All equivalent structural transformations made under the concept of the present utility model and using the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included in the patent protection scope of the present utility model.
Claims
1. A lightning protection grounding structure for a wind turbine generator, comprising a vertical grounding electrode (3) connected to the wind turbine foundation (1); characterized in that, Grounding boreholes (2) are uniformly arranged around the wind turbine foundation (1) in the circumferential direction, corresponding to the number of vertical grounding electrodes (3). The grounding boreholes (2) penetrate the high-resistivity rock layer and connect with the low-resistivity stratum, forming a high-resistivity rock layer section and a low-resistivity stratum section. There are rock fissures on the wall of the high-resistivity rock layer section. The vertical grounding electrode (3) is inserted into the grounding borehole (2), and its bottom end passes through the grounding borehole (2) and is inserted into the low-resistivity stratum. A conductive transition body (9) formed of graphene material is also filled under high pressure between the vertical grounding electrode (3) and the high-resistivity rock layer section of the grounding borehole and in the rock fissures of the high-resistivity rock layer section.
2. The wind turbine lightning protection grounding structure according to claim 1, characterized in that, The conductive transition body (9) formed by the graphene material is a condensation of graphene powder or graphene slurry.
3. The wind turbine lightning protection grounding structure according to claim 1 or 2, characterized in that, The vertical grounding electrode (3) is a hot-dip galvanized steel pipe.
4. The wind turbine lightning protection grounding structure according to claim 1 or 2, characterized in that, It also includes a horizontal grounding grid with a closed ring structure, the vertical grounding electrode (3) is connected to the horizontal grounding grid, and a connecting conductor (6) is uniformly arranged along the circumference on the horizontal grounding grid to connect the horizontal grounding grid with the wind turbine foundation (1).
5. The wind turbine lightning protection grounding structure according to claim 4, characterized in that, The horizontal grounding grid includes an inner grounding grid (5) and an outer grounding grid (4). Both the inner and outer grounding grids are closed ring structures and are concentrically arranged. The ring structure diameter of the outer grounding grid (4) is larger than that of the inner grounding grid (5). The vertical grounding electrode (3) is connected to the outer grounding grid (4). The inner and outer grounding grids are connected by a connecting conductor (6).
6. The wind turbine lightning protection grounding structure according to claim 5, characterized in that, It also includes an equalizing ring (7) installed on the wind turbine foundation (1), which is connected to the outer grounding grid (4) through a grounding lead (8).
7. The wind turbine lightning protection grounding structure according to claim 4, characterized in that, Multiple grounding modules are also installed at intervals on the horizontal grounding grid.