Lightning stroke protection structure of electric heating deicing system of wind power blade

Abstract

The utility model discloses a lightning stroke protection structure of a wind power blade electric heating deicing system, comprising a metal protection layer which is laid on the edge area of a heating unit of the electric heating deicing system in the length direction of a blade, and the metal protection layer and the heating unit are separated by using an insulating material. The power supply electrode in the edge area of the heating unit is shielded, so that the power supply electrode cannot form gathering of inductive charges during lightning stroke. The electric heating deicing system can be suitable for newly produced blades and can also be used for rectification and reformation of wind field blades, the structure can ensure that heating units on the surfaces of the blades are prevented from being damaged by lightning strokes, the electric heating deicing system reliably operates within the life cycle range, meanwhile, the breadth of needed metal protection can be greatly reduced, and therefore the use cost is effectively reduced, and the service life of the electric heating deicing system is prolonged. And the operability and the efficiency are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of wind turbine blades, in particular to a lightning protection structure of an electric heating deicing system for wind turbine blades. Background Art

[0002] To ensure reliability in thunderstorms, the blade electrothermal de-icing system of a wind turbine (referred to as a wind turbine) requires lightning protection. Conventional designs typically use metal mesh to fully cover the heating unit of the blade electrothermal de-icing system. This prevents direct lightning strikes from damaging the heating unit and, consequently, preventing lightning current from entering the de-icing system's control system and causing potential damage. However, this conventional design requires a relatively large metal mesh width, typically 700 to 1000 mm. This results in high costs, difficulty in on-site repairs and maintenance, and low efficiency. Furthermore, this design also involves unnecessary design and excessive protection. Utility Model Content

[0003] The purpose of the present utility model is to overcome the shortcomings and deficiencies of the prior art and to provide a lightning protection structure for an electric thermal de-icing system for wind turbine blades, which can be applied to newly produced blades and can also be used for the renovation of wind farm blades. The structure can ensure that the heating unit on the surface of the blade is protected from damage by lightning. While the electric thermal de-icing system can operate reliably within its life cycle, it can greatly reduce the width of the required metal protection, thereby effectively reducing the cost of use and improving operability and efficiency.

[0004] To achieve the above-mentioned purpose, the technical solution provided by the present invention is: a lightning protection structure of an electric thermal deicing system for wind turbine blades, comprising a metal protective layer, wherein the metal protective layer is laid on the edge area of ​​the heating unit of the electric thermal deicing system in the length direction of the blade, and an insulating material is used to separate the metal protective layer and the heating unit to shield the power supply electrode in the edge area of ​​the heating unit, so that the power supply electrode cannot form an accumulation of induced charges when lightning strikes.

[0005] Preferably, a single side of the metal protective layer extends beyond the edge area of ​​the heating unit by at least 10 mm.

[0006] Preferably, the width of the metal protective layer is 50 to 200 mm.

[0007] Preferably, the metal protective layer has a higher conductivity than the power supply electrode and can receive lightning first.

[0008] Preferably, the metal protective layer is connected to the mid-blade lightning receptor on the blade by bridging a section of the metal protective layer.

[0009] Preferably, the bridging section of the metal protective layer is located in the middle area of ​​the blade.

[0010] Preferably, the metal protective layer is connected to the blade tip lightning receptor on the blade.

[0011] Preferably, the metal protective layer is grounded separately.

[0012] Preferably, the metal protective layer is a metal mesh or a metal film.

[0013] Preferably, the heating unit is located in the leading edge region of the blade and extends in the length direction of the blade.

[0014] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0015] 1. Solve the problem of lightning damage to the electric heating de-icing system, ensure the normal operation of the blades during the strong wind season in winter, and ensure reliable operation within the life cycle.

[0016] 2. Accurate protection against lightning strikes on heating units can avoid useless designs and excessive protection, which lead to costs, construction complexity and reduced reliability.

[0017] 3. It can effectively reduce the usage of metal protection (such as metal mesh). The width of metal protection (such as metal mesh) can be reduced from the original 700-1000mm to 50-200mm, thereby reducing the cost of use.

[0018] 4. When adding a heating unit to an already operating unit, the modification of the lightning protection structure is operational, simple to lay, easy to install, fast and efficient, which ensures reliability and can effectively reduce the maintenance time of on-site modification. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the lightning protection structure provided in Example 1. DETAILED DESCRIPTION

[0020] The present invention will be described in further detail below with reference to the embodiments and drawings, but the embodiments of the present invention are not limited thereto.

[0021] Example 1

[0022] like Figure 1As shown, this embodiment discloses a lightning protection structure of an electrothermal deicing system for wind turbine blades, including a metal protective layer 1, which mainly provides precise protection against lightning strikes on the heating unit 2 of the electrothermal deicing system. The heating unit 2 is located in the leading edge area of ​​the blade 3 and extends in the length direction of the blade 3. The metal protective layer 1 is laid on the edge area in the length direction of the blade 3, and the metal protective layer 1 and the heating unit 2 are separated by an insulating material to shield the power supply electrode in the edge area of ​​the heating unit 2, so that the power supply electrode cannot form an induced charge accumulation when lightning strikes. In the middle area of ​​the blade, the metal protective layer 1 is connected to the leaf lightning rod 4 on the blade 3 by bridging a section of the metal protective layer 1 to ensure reliable grounding, so that the lightning current is conducted through the leaf lightning rod 4 and finally conducted to the ground through the blade down conductor, thereby achieving precise protection of the heating unit 2.

[0023] Specifically, one side of the metal protective layer 1 extends beyond the edge area of ​​the heating unit 2 by at least 10 mm to ensure the reliability of its overall protection; the width of the metal protective layer 1 is 50 to 200 mm, which is effectively reduced compared to the previous 700 to 1000 mm; the metal protective layer 1 can be in the form of a metal mesh or a metal film, and the material can be metal materials such as copper and aluminum.

[0024] Simulations and experimental tests show that high electric field areas on the blades are primarily concentrated at the edges of the heating elements. This is primarily due to the presence of the heating film's power supply electrodes, which have excellent electrical conductivity. During thunderstorms, a large amount of induced charge emanates from this area and concentrates at the edges. When the electric field strength of the charges in this area exceeds the breakdown field strength of the air, an arc forms, forming upward lightning strikes that attract downward lightning strikes from the thundercloud, ultimately leading to lightning strikes. The probability of lightning strikes in the central region of the heating element is extremely low. Therefore, direct lightning strike protection at the edges can meet practical requirements. This requires protection of the power supply electrodes and the edges of the heating elements. To achieve effective lightning protection, a metal protective layer must be applied to their surfaces. Furthermore, the metal protective layer applied to the surface of the power supply electrodes provides a shielding effect, preventing the accumulation of induced charge at the electrodes. Furthermore, the metal protective layer has better electrical conductivity than the electrodes and, being located on the surface of the electrodes, provides preferential lightning strike protection.

[0025] In summary, the lightning protection structure described in this embodiment effectively protects the heating unit of the electric heating deicing system, preventing lightning current from striking the heating unit and potentially damaging it. If the lightning current strikes the heating unit, it could infect the control unit of the electric heating deicing system, potentially causing lightning damage to the control system. This lightning protection structure effectively prevents lightning strikes on the heating unit, ensuring the safety of the electric heating deicing system and ensuring the blades' power generation during strong winter winds, making it worthy of widespread adoption.

[0026] In addition, this lightning protection structure is not only suitable for lightning protection of the heating unit of the electric thermal deicing system, but also for lightning protection of blades rich in conductive materials, such as blades rich in carbon fiber, conductors, semiconductors and other materials.

[0027] Example 2

[0028] The difference from Example 1 is that the metal protective layer 1 in this embodiment is connected to the blade tip lightning receptor on the blade 3 (not shown in the figure).

[0029] Example 3

[0030] The difference from Example 1 is that the metal protective layer 1 in this embodiment is grounded separately (not shown in the figure).

[0031] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A lightning protection structure for a wind turbine blade electrothermal deicing system, characterized in that: The invention comprises a metal protective layer (1), wherein the metal protective layer (1) is applied to the edge region of a heating unit (2) of an electric thermal deicing system in the length direction of a blade (3), and an insulating material is used to separate the metal protective layer (1) and the heating unit (2) so as to shield the power supply electrode in the edge region of the heating unit (2), so that the power supply electrode cannot form an accumulation of induced charges when a lightning strike occurs.

2. The lightning protection structure of the wind turbine blade electrothermal deicing system according to claim 1 is characterized in that: A single side of the metal protective layer (1) extends beyond the edge area of ​​the heating unit (2) by at least 10 mm.

3. The lightning protection structure of the wind turbine blade electrothermal deicing system according to claim 2, characterized in that: The width of the metal protective layer (1) is 50 to 200 mm.

4. The lightning protection structure of the wind turbine blade electrothermal deicing system according to claim 3 is characterized in that: The metal protective layer (1) has a higher electrical conductivity than the power supply electrode and can receive lightning first.

5. The lightning protection structure of the wind turbine blade electrothermal deicing system according to claim 4, characterized in that: The metal protective layer (1) is connected to the mid-blade lightning receptor (4) on the blade (3) by bridging a section of the metal protective layer (1).

6. The lightning protection structure of the wind turbine blade electrothermal deicing system according to claim 5, characterized in that: The bridging section of the metal protective layer (1) is located in the middle area of ​​the blade.

7. The lightning protection structure of the wind turbine blade electrothermal deicing system according to claim 4, characterized in that: The metal protective layer (1) is connected to the blade tip lightning receptor on the blade (3).

8. The lightning protection structure of the wind turbine blade electrothermal deicing system according to claim 4, characterized in that: The metal protective layer (1) is grounded separately.

9. A lightning protection structure for a wind turbine blade electrothermal deicing system according to any one of claims 1 to 8, characterized in that: The metal protective layer (1) is a metal mesh or a metal film.

10. The lightning protection structure of the wind turbine blade electrothermal deicing system according to claim 9, characterized in that: The heating unit (2) is located in the leading edge region of the blade (3) and extends in the length direction of the blade (3).

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