Lightning protection system fault diagnosis method and wind power blade lightning protection system

Abstract

The invention discloses a lightning protection system fault diagnosis method and a wind power blade lightning protection system, and relates to the technical field of wind power blade lightning protection. The method comprises the steps that S101, distributed monitoring nodes are adopted between lightning arresters of power generation blades and a grounding grid for detection, and each monitoring node comprises a broadband impedance sensor and an infrared thermal imaging module; when the detection module detects that the replaceable lightning arresting assembly breaks down, the control mechanism controls the replaceable lightning arresting assembly to rotate, so that the damaged part of the replaceable lightning arresting assembly is moved into the power generation blade, the new part is moved to the end of the power generation blade, power generation equipment does not need to be shut down for maintenance, and the power generation efficiency is improved. The lightning protection part is more convenient to replace; and when the sealing plate is stored in the movable cavity, the movable cavity is promoted to be opened, so that the rotating rod can drive the lightning arrester to rotate to move the damaged lightning arrester into the movable cavity to be stored, and the possibility that the damaged lightning arrester falls off is reduced.

Description

Technical Field

[0001] This invention relates to the field of lightning protection technology for wind turbine blades, and in particular to a fault diagnosis method for a lightning protection system and a lightning protection system for wind turbine blades. Background Technology

[0002] With the continuous development of the wind power industry, the blades of wind turbines are getting longer and longer, and the number of lightning strikes damaging wind turbine blades and other components is also increasing. Since wind turbine blades are expensive to manufacture and maintain, lightning strikes can cause huge economic losses. Therefore, it is necessary to design reasonable lightning protection for the blades. Wind turbines generally achieve lightning protection by using lightning arresters in conjunction with grounding grids, and use fault detection and diagnosis systems to test the lightning protection components.

[0003] Some existing wind turbines have lightning arresters installed at the ends of the blades. If the lightning arrester is damaged and the system continues to be used, a lightning strike may damage the system. However, since the lightning arrester is installed at the end of the blade, the system must be shut down before the lightning arrester can be replaced. Summary of the Invention

[0004] To address the aforementioned issue that the lightning arrester for wind turbines is installed at the end of the blades, and that continued use of the system when the arrester is damaged could lead to further damage from lightning strikes, and that replacing the arrester requires shutting down the system, the problem remains.

[0005] This invention provides a method for diagnosing faults in a lightning protection system and a lightning protection system for wind turbine blades, employing the following technical solution: A method for diagnosing faults in a lightning protection system includes the following steps; S101: Distributed monitoring nodes are used for detection between the lightning arrester of the generator blade and the grounding grid. Each monitoring node includes a wideband impedance sensor and an infrared thermal imaging module. The wideband impedance sensor operates at a frequency of 0.1-100MHz. S102: Construct a multi-physics coupling model and input the dynamic impedance phase angle θ, temperature rise gradient ΔT / Δt, and lightning current waveform distortion rate δ. The measurement accuracy of the dynamic impedance phase angle θ is ±0.1°, and the sensitivity of the temperature rise gradient ΔT / Δt is 0.1℃ / s. S103: When a fault is detected, an alarm is triggered by two levels of warning. The two levels of warning are primary warning and advanced warning. The primary warning is triggered when θ deviates from the reference value by more than 5° and ΔT / Δt is greater than 2℃ / s for 10s. The advanced warning is triggered when δ is greater than 15% accompanied by a sudden change in the real part of the impedance of more than 20%.

[0006] Optionally, the above-mentioned fault diagnosis method for lightning protection systems also includes adaptive threshold adjustment based on deep reinforcement learning, which is constructed through a Q-Learning decision model using the Q-Learning algorithm. The decision model includes seasonal factors and equipment aging index.

[0007] Another technical solution proposed by the present invention is a wind turbine blade lightning protection system, which further includes a power generation blade. The end of the power generation blade is provided with a replaceable lightning protection component. A control mechanism is provided inside the power generation blade. A detection module is provided inside the power generation blade, and the detection end of the detection module is connected to the replaceable lightning protection component.

[0008] Optionally, in the above-mentioned wind turbine blade lightning protection system, the generator blade has an internal movable cavity, and the replaceable lightning arrester, control mechanism and detection module are all installed inside the movable cavity.

[0009] Optionally, in the above-mentioned wind turbine blade lightning protection system, the replaceable lightning arrester assembly includes a rotating rod and two connecting rods. The rotating rod is rotatably inserted into the inner bottom wall of the movable cavity, one end of each of the two connecting rods is fixedly connected to the rotating rod, and the other end of each of the two connecting rods is fixedly equipped with a lightning arrester.

[0010] Optionally, in the above-mentioned wind turbine blade lightning protection system, the control mechanism includes an electric push rod, a movable plate, and a gear rod. The gear rod is rotatably inserted into the movable cavity. The lower end of the gear rod is connected to the lower end of the rotating rod through a transmission chain. The electric push rod is fixedly installed on the inner wall of the movable cavity. The movable plate is fixedly installed at the extended end of the electric push rod. A toothed plate is fixedly installed on the top of the movable plate, and the toothed plate meshes with the gear rod.

[0011] Optionally, in the above-mentioned wind turbine blade lightning protection system, the gear rod includes a vertical rod, a one-way bearing, and a first gear. The vertical rod is vertically rotatably disposed in the movable cavity. The one-way bearing is fixedly sleeved on the upper end of the vertical rod. The first gear is fixedly sleeved on the outer wall of the one-way bearing and meshes with the gear plate.

[0012] Optionally, in the above-mentioned wind turbine blade lightning protection system, the movable plate includes two sealing plates and a connecting plate. The two sealing plates are used to seal the two openings of the movable cavity, and the two sealing plates are connected by the connecting plate. The connecting plate is fixedly installed at the extended end of the electric push rod.

[0013] Optionally, in the above-mentioned wind turbine blade lightning protection system, the detection module includes a winding rod, a vertical plate, and a detection head. The upper end of the winding rod is rotatably inserted into the inner top wall of the movable cavity, and the lower end of the winding rod is movably inserted into the top surface of the rotating rod. The vertical plate is movably disposed in the inner top wall of the movable cavity and is connected to the inner wall of the movable cavity by a spring. The detection head is fixedly disposed in the side wall of the vertical plate, and the detection end of the detection head is inserted into the lightning arrester. The vertical plate is connected to the winding rod by a steel cable.

[0014] Optionally, in the above-mentioned wind turbine blade lightning protection system, a second gear is fixedly sleeved on the upper end of the winding rod, the second gear meshes with the gear plate, and a rubber ring is fixedly installed on the upper end of the winding rod.

[0015] In summary, the present invention has at least one of the following beneficial effects: When the detection module detects a fault in the replaceable lightning protection component, it controls the replacement lightning protection component to rotate through the control mechanism. This allows the damaged part of the replacement lightning protection component to be moved into the inside of the generator blade, and the new part to be moved to the end of the generator blade. This eliminates the need for the generator to be shut down for maintenance and makes it easier to replace the lightning protection components. When the sealing plate is retracted into the movable cavity, it causes the movable cavity to open, thereby enabling the rotating rod to rotate the lightning arrester and move the damaged lightning arrester into the movable cavity for storage, thus reducing the possibility of the damaged lightning arrester falling out. Attached Figure Description

[0016] Figure 1 This is a three-dimensional structural schematic diagram of the present invention; Figure 2 This is a partial three-dimensional structural schematic diagram of the power generation blade of the present invention; Figure 3 This is a partial three-dimensional structural cross-sectional view of the present invention; Figure 4 This is a partial three-dimensional structural schematic diagram of the control mechanism of the present invention; Figure 5 This is a schematic diagram of the partial three-dimensional unfolded structure of the present invention.

[0017] In the diagram: 1. Generating blade; 11. Movable cavity; 2. Replaceable lightning arrester assembly; 21. Rotating rod; 22. Connecting rod; 23. Lightning arrester; 3. Control mechanism; 31. Electric push rod; 32. Movable plate; 321. Sealing plate; 322. Connecting plate; 33. Gear rod; 331. Vertical rod; 332. One-way bearing; 333. First gear; 34. Transmission chain; 35. Gear plate; 4. Detection module; 41. Rewinding rod; 42. Vertical plate; 43. Detection head; 44. Spring; 45. Steel cable; 46. Second gear. Detailed Implementation

[0018] The following is in conjunction with the appendix Figures 1-5 The present invention will be described in further detail below.

[0019] Please refer to the attached diagram in the instruction manual. Figures 1-5 The present invention provides an embodiment of a fault diagnosis method for a lightning protection system, comprising the following steps; Step 1: Distributed monitoring nodes are used to detect the lightning arrester 23 of the generator blade 1 and the grounding grid. Each monitoring node includes a wideband impedance sensor and an infrared thermal imaging module. The wideband impedance sensor operates at a frequency of 0.1-100MHz. Step 2: Construct a multi-physics coupling model and input the dynamic impedance phase angle θ, temperature rise gradient ΔT / Δt, and lightning current waveform distortion rate δ. The measurement accuracy of the dynamic impedance phase angle θ is ±0.1°, and the sensitivity of the temperature rise gradient ΔT / Δt is 0.1℃ / s. Step 3: When a fault is detected, an alarm is triggered through two levels of warning. The two levels of warning are divided into primary warning and advanced warning. The primary warning is triggered when θ deviates from the reference value by more than 5° and ΔT / Δt > 2℃ / s for 10s. The advanced warning is triggered when δ > 15% accompanied by a sudden change in the real part of the impedance > 20%.

[0020] It also includes adaptive threshold adjustment based on deep reinforcement learning, which uses a Q-Learning decision model constructed through the Q-Learning algorithm. The decision model includes seasonal factors and equipment aging index.

[0021] It should be noted that the broadband impedance sensor and infrared thermal imaging module of the aforementioned distributed monitoring node are both existing products. The detection of the lightning protection system using the broadband impedance sensor and infrared thermal imaging module is an existing technology. Furthermore, the construction of the multi-physics coupling model and the Q-Learning algorithm are also existing technologies. The multi-physics coupling model is used to calculate the values ​​of dynamic impedance phase angle θ, temperature rise gradient ΔT / Δt, and lightning current waveform distortion rate δ. When a specified threshold is reached, a primary warning and an advanced warning are triggered.

[0022] To better demonstrate a fault diagnosis method for a lightning protection system, this embodiment proposes a lightning protection system for wind turbine blades, including a generator blade 1. A replaceable lightning arrester assembly 2 is installed at the end of the generator blade 1. A control mechanism 3 is installed inside the generator blade 1, and a detection module 4 is installed inside the generator blade 1. The detection end of the detection module 4 is connected to the replaceable lightning arrester assembly 2. When the detection module 4 detects a fault in the replaceable lightning arrester assembly 2, the control mechanism 3 controls the replaceable lightning arrester assembly 2 to rotate, so that the damaged part of the replaceable lightning arrester assembly 2 is moved into the generator blade 1, and the new part is moved to the end of the generator blade 1. This allows the power generation equipment to be maintained without shutdown, and makes the replacement of lightning protection components more convenient. It should be noted that the detection module 4 is electrically connected to the distributed monitoring node. The detection module 4 is used to detect the replaceable lightning arrester 2 and to diagnose the cause of the fault through distributed monitoring.

[0023] The generator blade 1 has a movable cavity 11 inside, and the replaceable lightning receiving component 2, the control mechanism 3 and the detection module 4 are all installed in the movable cavity 11. The movable cavity 11 facilitates the installation of the replaceable lightning receiving component 2, the control mechanism 3 and the detection module 4, and allows the replaceable lightning receiving component 2 to rotate.

[0024] The replaceable lightning arrester assembly 2 includes a rotating rod 21 and two connecting rods 22. The rotating rod 21 is rotatably inserted into the inner bottom wall of the movable cavity 11. One end of each of the two connecting rods 22 is fixedly connected to the rotating rod 21, and a lightning arrester 23 is fixedly installed at the other end of each of the two connecting rods 22. When the rotating rod 21 rotates, it facilitates the rotation of the connecting rods 22 and the lightning arrester 23. When the lightning arrester 23 in use is damaged, the unused lightning arrester 23 is moved to the end of the generator blade 1 by rotating the rotating rod 21 by 90°, and the damaged lightning arrester 23 is stored in the movable cavity 11.

[0025] The control mechanism 3 includes an electric push rod 31, a movable plate 32, and a gear rod 33. The gear rod 33 is rotatably inserted into the movable cavity 11. The lower end of the gear rod 33 is connected to the lower end of the rotating rod 21 through a transmission chain 34. The electric push rod 31 is fixedly installed on the inner wall of the movable cavity 11. The movable plate 32 is fixedly installed at the extended end of the electric push rod 31. A toothed plate 35 is fixedly installed on the top of the movable plate 32. The toothed plate 35 meshes with the gear rod 33. The electric push rod 31 facilitates the synchronous movement of the movable plate 32 and the toothed plate 35. When the toothed plate 35 meshes with the gear rod 33, it facilitates the rotation of the gear rod 33. At the same time, the transmission chain 34 drives the rotating rod 21 to rotate synchronously. As the rotating rod 21 rotates, it facilitates the replacement of the lightning arrester 23.

[0026] It should be noted that transmission chain 34 is a conventional transmission component.

[0027] The gear rod 33 includes a vertical rod 331, a one-way bearing 332, and a first gear 333. The vertical rod 331 is vertically rotatably mounted in the movable cavity 11. The one-way bearing 332 is fixedly sleeved on the upper end of the vertical rod 331. The first gear 333 is fixedly sleeved on the outer wall of the one-way bearing 332. The first gear 333 meshes with the toothed plate 35. When the toothed plate 35 moves toward the vertical rod 331, it drives the first gear 333 and the one-way bearing 332 to rotate. At this time, the one-way bearing 332 is in a locked state, thereby driving the vertical rod 331 to rotate through the one-way bearing 332, and driving the rotating rod 21 to rotate synchronously through the transmission chain 34. When the toothed plate 35 is reset, it drives the first gear 333 and the one-way bearing 332 to rotate in the opposite direction. At this time, the one-way bearing 332 is in an unlocked state, thereby keeping the vertical rod 331 and the rotating rod 21 stationary, reducing the possibility of the lightning arrester 23 needing to be replaced and reset again.

[0028] The movable plate 32 includes two sealing plates 321 and a connecting plate 322. The two sealing plates 321 are used to seal the two openings of the movable cavity 11. The two sealing plates 321 are connected by the connecting plate 322. The connecting plate 322 is fixedly installed at the extended end of the electric push rod 31. The two sealing plates 321 cooperate to seal the openings of the movable cavity 11, thereby reducing the possibility of debris entering the movable cavity 11. The connecting plate 322 cooperates with the electric push rod 31 to facilitate the synchronous movement of the sealing plates 321. When the sealing plates 321 are retracted into the movable cavity 11, the movable cavity 11 is opened, thereby causing the rotating rod 21 to drive the lightning arrester 23 to rotate and move the damaged lightning arrester 23 into the movable cavity 11 for storage.

[0029] The detection module 4 includes a winding rod 41, a vertical plate 42, and a detection head 43. The upper end of the winding rod 41 is rotatably inserted into the inner top wall of the movable cavity 11, and the lower end of the winding rod 41 is movably inserted into the top surface of the rotating rod 21. The vertical plate 42 is movably disposed on the inner top wall of the movable cavity 11 and is connected to the inner wall of the movable cavity 11 by a spring 44. The detection head 43 is fixedly disposed on the side wall of the vertical plate 42, and the detection end of the detection head 43 is inserted into the lightning arrester 23. The vertical plate 42 is connected to the winding rod 41 by a steel cable 45. When the winding rod 41 winds up the steel cable 45, it pulls the vertical plate 42 and the detection head 43 to move, causing the detection head 43 to separate from the lightning arrester 23. At this time, the lightning arrester 23 can rotate with the rotating rod 21 for replacement.

[0030] A second gear 46 is fixedly sleeved on the upper end of the winding rod 41. The second gear 46 meshes with the toothed plate 35. A rubber ring is fixedly installed on the upper end of the winding rod 41. When the movable plate 32 moves toward the interior of the movable cavity 11, it drives the toothed plate 35 to move synchronously. At this time, the toothed plate 35 drives the second gear 46 and the winding rod 41 to rotate. Then, the winding rod 41 winds up the steel cable 45 to cause the detection head 43 to separate from the lightning arrester 23. Then, the toothed plate 35 drives the rotating rod 21 to rotate and move the damaged lightning arrester 23 into the movable cavity 11. When the moving plate 32 resets, it drives the toothed plate 35 to move synchronously. At this time, the toothed plate 35 drives the second gear 46 to rotate in the opposite direction to the winding rod 41, thereby releasing the steel cable 45. Then, the spring 44 pushes the vertical plate 42 and the detection head 43 to move, thereby causing the detection head 43 to be inserted into the lightning arrester 23 for detection. The rubber ring increases the friction between the winding rod 41 and the inner wall of the moving cavity 11, reducing the possibility that the spring 44 will push the vertical plate 42 and the detection head 43 to reset when the toothed plate 35 and the second gear 46 separate.

[0031] The above are all preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A method for diagnosing faults in a lightning protection system, characterized in that, Includes the following steps; S101: Distributed monitoring nodes are used to detect the lightning arrester (23) of the generator blade (1) and the grounding grid. Each monitoring node includes a wideband impedance sensor and an infrared thermal imaging module. The working frequency of the wideband impedance sensor is 0.1-100MHz. S102: Construct a multi-physics coupling model and input the dynamic impedance phase angle θ, temperature rise gradient ΔT / Δt, and lightning current waveform distortion rate δ. The measurement accuracy of the dynamic impedance phase angle θ is ±0.1°, and the sensitivity of the temperature rise gradient ΔT / Δt is 0.1℃ / s. S103: When a fault is detected, an alarm is triggered by two levels of warning. The two levels of warning are primary warning and advanced warning. The primary warning is triggered when θ deviates from the reference value by more than 5° and ΔT / Δt is greater than 2℃ / s for 10s. The advanced warning is triggered when δ is greater than 15% accompanied by a sudden change in the real part of the impedance of more than 20%.

2. The fault diagnosis method for a lightning protection system according to claim 1, characterized in that: It also includes adaptive threshold adjustment based on deep reinforcement learning, which uses a Q-Learning decision model constructed through the Q-Learning algorithm. The decision model includes seasonal factors and equipment aging index.

3. A lightning protection system for wind turbine blades, comprising the lightning protection system fault diagnosis method according to any one of claims 1-2, and further comprising a power generation blade (1), wherein a replaceable lightning protection component (2) is provided at the end of the power generation blade (1), a control mechanism (3) is provided inside the power generation blade (1), and a detection module (4) is provided inside the power generation blade (1), wherein the detection end of the detection module (4) is connected to the replaceable lightning protection component (2).

4. The wind turbine blade lightning protection system according to claim 3, characterized in that: The generator blade (1) has an internal movable cavity (11), and the replaceable lightning rod (2), control mechanism (3) and detection module (4) are all installed inside the movable cavity (11).

5. The wind turbine blade lightning protection system according to claim 4, characterized in that: The replaceable lightning arrester assembly (2) includes a rotating rod (21) and two connecting rods (22). The rotating rod (21) is rotatably inserted into the inner bottom wall of the movable cavity (11). One end of each of the two connecting rods (22) is fixedly connected to the rotating rod (21), and the other end of each of the two connecting rods (22) is fixedly provided with a lightning arrester (23).

6. The wind turbine blade lightning protection system according to claim 5, characterized in that: The control mechanism (3) includes an electric push rod (31), a movable plate (32), and a gear rod (33). The gear rod (33) is rotatably inserted into the movable cavity (11). The lower end of the gear rod (33) is connected to the lower end of the rotating rod (21) through a transmission chain (34). The electric push rod (31) is fixedly installed on the inner wall of the movable cavity (11). The movable plate (32) is fixedly installed at the extended end of the electric push rod (31). A toothed plate (35) is fixedly installed on the top of the movable plate (32). The toothed plate (35) meshes with the gear rod (33).

7. The wind turbine blade lightning protection system according to claim 6, characterized in that: The gear rod (33) includes a vertical rod (331), a one-way bearing (332), and a first gear (333). The vertical rod (331) is vertically rotatably disposed in the movable cavity (11). The one-way bearing (332) is fixedly sleeved on the upper end of the vertical rod (331). The first gear (333) is fixedly sleeved on the outer wall of the one-way bearing (332). The first gear (333) meshes with the gear plate (35).

8. The wind turbine blade lightning protection system according to claim 6, characterized in that: The movable plate (32) includes two sealing plates (321) and a connecting plate (322). The two sealing plates (321) are used to seal the two openings of the movable cavity (11). The two sealing plates (321) are connected by the connecting plate (322), which is fixedly installed at the extended end of the electric push rod (31).

9. The wind turbine blade lightning protection system according to claim 6, characterized in that: The detection module (4) includes a winding rod (41), a vertical plate (42), and a detection head (43). The upper end of the winding rod (41) is rotatably inserted into the inner top wall of the movable cavity (11), and the lower end of the winding rod (41) is movably inserted into the top surface of the rotating rod (21). The vertical plate (42) is movably disposed in the inner top wall of the movable cavity (11). The vertical plate (42) is connected to the inner wall of the movable cavity (11) by a spring (44). The detection head (43) is fixedly disposed in the side wall of the vertical plate (42). The detection end of the detection head (43) is inserted into the lightning arrester (23). The vertical plate (42) is connected to the winding rod (41) by a steel cable (45).

10. The wind turbine blade lightning protection system according to claim 9, characterized in that: The upper end of the winding rod (41) is fixedly fitted with a second gear (46), which meshes with the toothed plate (35). A rubber ring is fixedly provided on the upper end of the winding rod (41).

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