Fan blade lightning protection detection structure
By setting up a series connection between the slip ring and the contact head on the wind turbine blade, lightning protection detection is achieved during the operation of the wind turbine, solving the low efficiency and wear problems caused by wind turbine shutdown detection, improving power generation efficiency and reducing costs.
Patent Information
- Application Number
- CN202423086930.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-13
- Publication Date
- 2025-09-16
- Estimated Expiration
- 2034-12-13
AI Technical Summary
The lightning protection system inspection of wind turbines requires the turbine to be shut down, which affects power generation efficiency and may cause wear and tear of the mechanical and electrical systems. Frequent shutdowns will shorten the life of the wind turbine.
A lightning protection detection structure for wind turbine blades is designed. By connecting the slip ring and the contact head in series, detection can be performed during the operation of the wind turbine. The structure includes a combination of a lightning receptor, a conductive head, a slip ring, a detection contact and an oscilloscope probe, enabling detection without stopping the turbine.
It enables lightning protection detection during wind turbine operation, improves power generation efficiency, reduces costs, and reduces wear and tear on mechanical and electrical systems.
Smart Images
Figure CN223344202U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of wind turbines, in particular to a lightning protection detection structure for wind turbine blades. Background Art
[0002] A wind turbine is a device that converts wind energy into electrical energy. It has many advantages such as being clean and renewable. Wind turbines mainly rely on wind rotors to capture wind energy. When wind blows through the blades, the blades' special aerodynamic design causes force to be applied to the blades, driving the wind rotor to rotate. The wind rotor transmits the rotational mechanical energy to the generator through the transmission system, and the generator then converts the mechanical energy into electrical energy. Wind turbine lightning protection system inspection is the process of inspecting, testing, and evaluating the lightning protection facilities of wind turbines to ensure that the lightning protection system can effectively protect the safe operation of wind turbines in lightning weather.
[0003] During the inspection of the lightning protection system of a wind turbine, the wind turbine needs to be shut down for inspection because the wind turbine is in a stationary state at this time. There is no electromagnetic field and vibration interference during operation. The inspection environment is relatively stable, and the threat to the safety of the inspectors is relatively small. The operation is relatively convenient. However, the wind turbine shutdown inspection requires the suspension of the wind turbine operation, which will affect the power generation efficiency of the wind farm and cause certain economic losses. In addition, frequent shutdown inspections may cause certain wear and tear on the mechanical components and electrical systems of the wind turbine, shortening the service life of the wind turbine. Utility Model Content
[0004] In response to the shortcomings of the existing technology, the utility model provides a wind turbine blade lightning protection detection structure. The lightning rod and the detection contact are always kept in a series state. Even if the wind turbine is running, detection can still be performed without suspending the operation of the wind turbine, thereby improving the power generation efficiency of the wind farm and reducing the cost.
[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: a wind turbine blade lightning protection detection structure, comprising a wind turbine body and a plurality of blade bodies installed on the wind turbine body, a telescopic rod is installed on the outside of the bracket of the wind turbine body, a spring telescopic device is installed on the upper end of the telescopic rod, a detection contact is fixedly installed on one end of the spring telescopic device, a conductive head is installed on one end of the detection contact, an oscilloscope probe with a BNC interface is provided on the wind turbine body, and a down conductor and a conducting wire are installed between the oscilloscope probe and the detection contact.
[0006] Slip rings in contact with the contact heads are fixedly installed on the outside of several blades. Contact heads with elliptical cross-sections are rotatably installed between the conductive heads and the slip rings. A lightning receptor is installed at the tip of each blade body. A wire is installed at one end of each lightning receptor. Multiple wires are installed inside multiple blade bodies respectively, and the other ends are connected to the slip rings.
[0007] Preferably, the spring expansion and contraction device includes a sleeve A, a sleeve B and a spring, sleeve A and sleeve B are slidingly connected, and the ends of the two sleeves away from each other are sealed, and sleeve A and sleeve B are fixedly connected to the two ends of the spring respectively.
[0008] Preferably, the wires, contact heads, conductive heads and slip rings are all made of conductive materials.
[0009] Preferably, the outermost ring of the slip ring is provided with a ring-shaped groove, the width of the contact head is smaller than the width of the groove, and the arc surface of the groove fits with the arc surface of the contact head.
[0010] Preferably, the slip ring is located outside the hub in the fan body.
[0011] Preferably, a U-shaped rod is fixedly connected to the outer side of the tower in the wind turbine body, and the outer side of the U-shaped rod is fixed to one end of the telescopic rod via a brake.
[0012] Preferably, a grounding wire is connected in parallel to the outside of the conductive head, and the grounding wire is fixed to the telescopic rod through a clamp.
[0013] Compared with the prior art, the utility model has the following beneficial effects: the slip ring is fixed to several blades through the arrangement, and when the wind turbine is running, the slip ring rotates with the blades, and the groove of the slip ring fits with the arc surface of the contact head. When the slip ring rotates, the lightning rod and the detection contact always remain in a series state. Even if the wind turbine is running, detection can still be carried out without suspending the operation of the wind turbine, thereby improving the power generation efficiency of the wind farm and reducing the cost. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 This is a schematic diagram of the structure of the fan body of the utility model;
[0015] Figure 2 For this utility model Figure 1 A schematic diagram of the structure at center A;
[0016] Figure 3 This is a cross-sectional view of the conductor, blade body and slip ring of the utility model;
[0017] Figure 4 It is a cross-sectional view of the side view of the slip ring and the contact head of the utility model;
[0018] Figure 5 It is a cross-sectional view of the side view of the telescopic rod of the utility model;
[0019] Figure 6 This is a cross-sectional view of a top view of the telescopic rod of the utility model when it is connected to the U-shaped rod through the brake;
[0020] Figure 7This is a schematic diagram of the U-shaped rod structure of the utility model;
[0021] Figure 8 This is a schematic diagram of the structure of the connection between the oscilloscope probe and the detection contact of the utility model.
[0022] Among them: 1. Wind turbine body; 2. Blade body; 3. Telescopic rod; 4. Spring telescopic device; 401. Sleeve A; 402. Sleeve B; 5. Detection contact; 6. Conductive head; 7. Slip ring; 8. Contact head; 9. Lightning arrester; 10. Wire; 11. Groove; 12. Brake; 13. Grounding wire; 14. Clamp; 15. U-shaped rod; 16. Oscilloscope probe; 17. Down conductor; 18. Live wire. DETAILED DESCRIPTION
[0023] like Figures 1-8 As shown, a wind turbine blade lightning protection detection structure includes a wind turbine body 1 and several blade bodies 2 installed on the wind turbine body 1, a telescopic rod 3 is installed on the outside of the bracket of the wind turbine body 1, and a U-shaped rod 15 is fixedly connected to the outside of the tower in the wind turbine body 1. The outer side of the U-shaped rod 15 is fixed to one end of the telescopic rod 3 through a brake 12. The brake 12 includes a brake disc, a brake block, a brake spring and a driving mechanism. When the brake 12 needs to work, the driving mechanism presses the brake block tightly against the brake disc. The friction generated between the brake block and the brake disc will prevent the rotation of the brake disc, thereby achieving the fixation of the U-shaped rod 15 connected to the brake disc and the telescopic rod 3. A spring telescopic device 4 is installed on the upper end of the telescopic rod 3. The spring telescopic device 4 includes a sleeve A401, a sleeve B402 and a spring. The sleeve A401 slides with the sleeve B402 The spring is in a compressed state. A detachable detection contact 5 is fixedly mounted on one end of the spring expansion and contraction device 4. A conductive head 6 is mounted on one end of the detection contact 5. An oscilloscope probe 16 with a BNC interface is provided on the fan body 1. A down conductor 17 and a conducting wire 18 are installed between the oscilloscope probe 16 and the detection contact 5. A grounding wire 13 is connected in parallel to the outside of the conductive head 6. The grounding wire 13 is fixed to the telescopic rod 3 through a clamp 14. Several grounding wires 13 are provided, and several clamps 14 are provided. Multiple clamps 14 can improve the stability of the grounding wire 13. Multiple grounding wires 13 connected in parallel can effectively increase the grounding area, thereby reducing the grounding resistance.
[0024] The outer sides of several blades are fixedly installed with slip rings 7 in contact with the contact heads 8. The slip rings 7 are located on the outer side of the hub in the wind turbine body 1. A contact head 8 with an elliptical cross-section is rotatably installed between the conductive head 6 and the slip ring 7. The contact head 8 is in contact with both the conductive head 6 and the slip ring 7. The outermost ring of the slip ring 7 is provided with a ring-shaped groove 11. The width of the contact head 8 is smaller than the width of the groove 11. The arc surface of the groove 11 fits the arc surface of the contact head 8. A lightning receptor 9 is installed at the tip of each blade body 2. A wire 10 is installed at one end of each lightning receptor 9. The wire 10, the contact head 8, the conductive head 6 and the slip ring 7 are all made of conductive material. The contact head 8 can be made of copper. Copper is an excellent conductor with high Electrical conductivity and thermal conductivity. In the lightning protection system, copper has good corrosion resistance and can work stably for a long time in various environments. Multiple wires 10 are respectively installed inside multiple blade bodies 2, and the other ends are connected to the slip ring 7. The current at the lightning rod 9 passes through the wire 10, slip ring 7, contact head 8, conductive head 6 and detection contact 5 in sequence. The detection contact 5 is energized with the oscilloscope probe 16 through the power line 18. The detection contact 5 transmits the signal to the oscilloscope probe 16 through the down conductor 17. The oscilloscope probe 16 detects the signal and transmits it to the detection equipment. The detection equipment needs to collect signals from the oscilloscope and judge whether the lightning protection system is operating normally by analyzing these signals. It should be noted that because the blade body 2 is rotating.
[0025] Working principle:
[0026] First, three lightning receptors 9 are installed on the tips of the three blade bodies 2 respectively. Each lightning receptor 9 is connected to a wire 10. The wire 10 is installed inside the blade body 2, and the other end is connected to the slip ring 7 fixed on the three blades; the telescopic rod 3 can be extended upward. It should be noted that the telescopic rod 3 can be connected to an external hydraulic device or an inflation device, that is, liquid or gas is filled into the telescopic rod 3, and the extension action of the telescopic rod 3 is controlled by the hydraulic device or the inflation device; the top of the telescopic rod 3 drives the spring telescopic device 4, the detection contact 5, and the conductive head 6 to move toward the slip ring 7, and the contact head 8 is installed between the groove 11 of the slip ring 7 and the conductive head 6. It is necessary to ensure that the contact head 8 It can rotate along the arc surface of the groove 11 and the upper end of the conductive head 6. As the telescopic rod 3 continues to extend, the spring inside the spring telescopic device 4 begins to compress. At this time, the telescopic rod 3 should immediately stop extending, and the elastic deformation force of the spring is used to apply an upward force to the detection contact 5. The detection contact 5 applies an upward thrust to the contact head 8 through the conductive head 6, so that the contact head 8 is in close contact with the conductive head 6 and the groove 11. It should be noted that the elastic deformation of the spring should not be too large. It is only necessary to make the contact head 8 in close contact with the conductive head 6 and the groove 11. At this time, a series circuit is formed between the lightning rod 9, the wire 10, the slip ring 7, the contact head 8, the conductive head 6 and the detection contact 5, which is convenient for subsequent detection work.
[0027] Next, the U-shaped rod 15 installed on the outside of the tower in the wind turbine body 1 is fixed to one end of the telescopic rod 3 through the brake 12 to improve the stability of the telescopic rod 3, and then the grounding wire 13 is connected in series with the conductive head 6. The grounding wire 13 is used to pass the current to the ground, and then the grounding wire 13 is fixed to the telescopic rod 3 through the clamp 14. It is recommended to set several grounding wires 13 and several clamps 14. This is because when connected in parallel, the reciprocal of the total resistance is equal to the sum of the reciprocals of the individual resistances, which means that the total resistance of multiple smaller resistors in parallel will be smaller than any individual resistance. Multiple grounding wires 13 connected in parallel can effectively increase the grounding area, thereby reducing the grounding resistance, and multiple clamps 14 can improve the stability of the grounding wire 13.
[0028] Finally, when the fan body 1 is in use, the blade body 2 will drive the slip ring 7 to rotate, and the position of the contact head 8 that is in rotational contact with the groove 11 of the slip ring 7 remains unchanged. During the rotation of the slip ring 7, the friction force will drive the contact head 8 to rotate. On the one hand, the rotation of the contact head 8 can reduce the resistance between the slip ring 7 and avoid damage to the device due to excessive force. On the other hand, under the action of the spring, it is ensured that the contact head 8 and the slip ring 7 always maintain contact. Therefore, during the rotation of the blade body 2, the contact head 8 and the slip ring 7 always maintain an energized state. It should be noted that the lightning protection system in the fan is essentially to attract lightning through the lightning rod 9, and the lightning transmits the current to the conductor 10, slip ring 7, contact head 8, conductor 7, etc. in sequence through the lightning rod 9. The electric head 6 and the detection contact 5, the detection contact 5 transmits the detection signal to the detection equipment, and the detection equipment determines whether the lightning protection system is operating normally by analyzing these signals; it should be noted that since the cross-section of the contact head 8 is elliptical, the contact head 8 is rugby-shaped as a whole, and the outer ring part of the contact head 8 fits together with the groove 11, not only the contact area is small so that the rotation resistance is small, but also the arc contact is made, so that the contact head 8 remains in the center position of the contact part with the groove 11 during rotation, and the stability is higher; in summary, the lightning rod 9 and the detection contact 5 are always kept in series, even if the wind turbine is in operation, detection can still be carried out without suspending the operation of the wind turbine, thereby improving the power generation efficiency of the wind farm and reducing the cost.
[0029] It should be noted that the metal tower of the wind turbine body 1 is an effective conductor with a large surface and area, which can lead the lightning current to the ground. The tower is connected to the earth end system in the foundation. The tower is usually divided into several sections. The connecting flange surfaces between the towers are not painted to ensure that the upper and lower flange surfaces are connected by metal surfaces to metal surfaces, so that the electrical connection between the two sections of the tower is complete and the lightning current can pass through quickly; the nacelle cover of the wind turbine body 1 is pre-embedded with equipotential metal strips, so that the entire nacelle cover becomes a Faraday cage, which can provide protection for the internal components. The nacelle frame is made of metal, and its own structural parts can serve as a good natural connector. In the part where external components enter the nacelle, surge protectors are installed where necessary and shielding measures are taken. The lightning current passing through the nacelle is guided to the tower through the yaw part and further flows into the ground. The yaw part is equipped with multiple carbon brushes to reduce the connection impedance between the nacelle and the tower. The lightning current from the blade body 2 or the guide cover will pass through the hub. The hub casting is made of metal and is connected to the inner ring of the generator bearing. Several carbon brushes on the inner ring of the bearing guide the lightning current through the main shaft to the nacelle. The generator casing is also made of metal and is connected to the outer ring of the bearing. Carbon brushes are also installed between the inner and outer rings of the generator bearing to guide the lightning current on the generator casing to the main shaft through the carbon brushes. , to avoid lightning current damaging the bearings. The inner ring of the bearing is isolated from the main shaft and the hub by insulating plates, and the lightning current flows directly from the hub to the main shaft through the insulating studs; several lightning receptors 9 are installed on the blade body 2. When lightning hits the lightning receptor 9, the current will reach the blade root through the complete down conductor 17. The blade root and the carbon brushes in the hub are connected by a whole torsion-resistant cable to avoid the lightning current passing directly through the pitch bearing. The torsion-resistant cable is directly connected to the carbon brushes on the outer ring of the generator bearing, so that the lightning current flows to the nacelle and further flows into the earth end.
[0030] Then, there are three traditional detection methods. The first is to use a liftable cage to lift people to the level of the blade tip of the wind turbine blade, and use a rope to pull the cage to the blade. The tip of the blade lightning rod 9 is located at the very tip of the blade and cannot be directly approached. When checking the appearance of the lightning rod 9, it can only be inspected or measured by standing outside the window on the top of the cabin using a telescope or a hanging basket. This results in that if a telescope is used, it is easily affected by uncertain factors such as weather and eyesight, and the detection result is not accurate enough. If a hanging basket is used, a large crane is required to hang the hanging basket for operation. Since the wind turbines are mostly located in remote mountainous areas, deserts or on the sea, the inspection and maintenance costs are too high. The second method is to use a drone to carry a detection line, and hang one end of the line on the lightning rod 9 to achieve detection, but It is easily affected by the wind speed of the day, which tests the stability of the drone and the skills of the operator. If you are not careful, the drone will damage the blades, and some blade lightning rods 9 are not protruding, making it difficult to hang the line; the third method is to use a long carbon fiber rod to directly support the lightning rod 9 and directly detect the working condition of the lightning rod 9. It is simple, efficient and low-cost, and a carbon fiber rod costs 10,000 to 20,000 yuan; and in this wind turbine blade lightning protection detection structure, the lightning rod 9 is located at the tip of the blade body 2, which is connected to the blade lightning protection down conductor 17, and the down conductor 17 is connected to the cabin equipotential busbar through cables and equipment (which can be other conductors), and the grounding wire 13 conducts lightning from the equipotential busbar to the earth, which can perform high-precision, high-efficiency and low-cost detection on the lightning protection system of the wind turbine blade, thereby effectively solving the above-mentioned technical problems.
[0031] Although the embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. A wind turbine blade lightning protection detection structure, comprising a wind turbine body (1) and a plurality of blade bodies (2) mounted on the wind turbine body (1), characterized in that: A telescopic rod (3) is installed on the outer side of the bracket of the fan body (1), a spring telescopic device (4) is installed on the upper end of the telescopic rod (3), a detection contact (5) is fixedly installed on one end of the spring telescopic device (4), a conductive head (6) is installed on one end of the detection contact (5), an oscilloscope probe (16) with a BNC interface is provided on the fan body (1), and a down conductor (17) and a conducting wire (18) are installed between the oscilloscope probe (16) and the detection contact (5); A slip ring (7) in contact with a contact head (8) is fixedly installed on the outer sides of a plurality of blades, a contact head (8) with an elliptical cross-section is rotatably installed between the conductive head (6) and the slip ring (7), a lightning receptor (9) is installed at the tip of each blade body (2), a conductor (10) is installed at one end of each lightning receptor (9), and a plurality of conductors (10) are respectively installed inside a plurality of blade bodies (2), and the other ends of the conductors are connected to the slip ring (7).
2. A wind turbine blade lightning protection detection structure according to claim 1, characterized in that: The spring expansion and contraction device (4) comprises a sleeve A (401), a sleeve B (402) and a spring. The sleeve A (401) and the sleeve B (402) are slidably connected, and the ends of the sleeves that are away from each other are both sealed. The sleeve A (401) and the sleeve B (402) are respectively fixedly connected to the two ends of the spring.
3. The wind turbine blade lightning protection detection structure according to claim 1, characterized in that: The conductor (10), contact head (8), conductive head (6) and slip ring (7) are all made of conductive material.
4. The wind turbine blade lightning protection detection structure according to claim 1, characterized in that: The outermost ring of the slip ring (7) is provided with a ring-shaped groove (11), the width of the contact head (8) is smaller than the width of the groove (11), and the arc surface of the groove (11) fits the arc surface of the contact head (8).
5. The wind turbine blade lightning protection detection structure according to claim 1, characterized in that: The slip ring (7) is located outside the hub in the fan body (1).
6. The wind turbine blade lightning protection detection structure according to claim 1, characterized in that: A U-shaped rod (15) is fixedly connected to the outer side of the tower in the wind turbine body (1), and the outer side of the U-shaped rod (15) and one end of the telescopic rod (3) are fixed via a brake (12).
7. The wind turbine blade lightning protection detection structure according to claim 1, characterized in that: A grounding wire (13) is connected in parallel to the outside of the conductive head (6), and the grounding wire (13) is fixed to the telescopic rod (3) via a clamp (14).