Monitoring device for breakage of hub connecting bolt of wind generating set

Abstract

The utility model relates to the field of wind turbine generator set monitoring, and particularly discloses a wind turbine generator set hub connecting bolt fracture monitoring device, a wind turbine generator set comprises a cabin and a main shaft, and the main shaft is connected with a hub through a connecting flange and a plurality of connecting bolts; a generator and a gearbox are arranged in the cabin, the input end of the gearbox is connected to the main shaft, the output end of the gearbox is connected with a high-speed shaft, and the high-speed shaft is connected to the input end of the generator; the high-speed shaft is coaxially connected with a brake disc, and a plurality of tooth parts are evenly arranged on the peripheral side of the brake disc. The monitoring device comprises a first detection piece and a second detection piece, and the first detection piece faces the motion trail of the connecting bolts and is used for detecting the number of the connecting bolts passing through the first detection piece in unit time when the connecting flange rotates; the motion trail of the second detection piece towards the tooth parts is used for detecting the number of the tooth parts passing through the second detection piece in unit time when the brake disc rotates. According to the invention, online monitoring of fracture of the connecting bolt between the hub and the main shaft can be realized.

Description

Technical Field

[0001] This application relates to the field of wind turbine monitoring, and in particular to a monitoring device for the fracture of hub connecting bolts in wind turbine generators. Background Technology

[0002] High-strength bolts are used to connect the tower sections, hub and main shaft, and blades and hub of a wind turbine. The reliability of these bolts is essential for the safe operation of the wind turbine. During turbine operation, the connecting bolts between the tower sections, blades, and hub are relatively stationary and can be monitored online in real time using methods such as the rotation method, ultrasonic method, and strain method. However, during turbine operation, the hub rotates with the main shaft, and the position of the connecting bolts between the hub and the main shaft relative to the nacelle is constantly changing. The aforementioned commonly used monitoring methods are insufficient for online monitoring of the connecting bolts between the hub and the main shaft. Therefore, these bolts are mainly inspected manually on a periodic basis, which is not only inefficient but also prone to missed inspections, making it difficult to guarantee real-time detection of the bolt connection status and posing a significant safety hazard to the turbine's operation. Utility Model Content

[0003] To enable online monitoring of broken connecting bolts between the hub and the main shaft, this application provides a monitoring device for broken connecting bolts of a wind turbine hub.

[0004] The monitoring device for the fracture of the hub connecting bolts of a wind turbine generator provided in this application adopts the following technical solution:

[0005] A monitoring device for the fracture of hub connecting bolts in a wind turbine generator set, wherein the wind turbine generator set includes a nacelle and a main shaft rotatably disposed in the nacelle, the main shaft being connected to a hub via a connecting flange and multiple connecting bolts; a generator and a gearbox are disposed in the nacelle, the input end of the gearbox is connected to the main shaft, the output end of the gearbox is connected to a high-speed shaft, the high-speed shaft being connected to the input end of the generator; a brake disc is coaxially connected to the high-speed shaft, and multiple teeth are evenly arranged on the circumference of the brake disc;

[0006] The monitoring device includes:

[0007] The first detection element is fixedly installed in the cabin. The movement trajectory of the first detection element toward the connecting bolt is used to detect the number of connecting bolts passing the first detection element per unit time when the connecting flange rotates.

[0008] The second detection element is fixedly installed in the engine compartment. The movement trajectory of the second detection element toward the teeth is used to detect the number of teeth passing through the second detection element per unit time when the brake disc rotates.

[0009] Furthermore, both the first detection element and the second detection element are proximity sensors.

[0010] Furthermore, both the first detection element and the second detection element are voltage-type proximity sensors.

[0011] Furthermore, the orientation of the first detection element is parallel to the axial direction of the connecting flange.

[0012] Furthermore, the orientation of the second detection element is parallel to the axial direction of the brake disc.

[0013] Furthermore, the distance between the first detection component and the connecting bolt is 10-20mm, and the axial distance between the second detection component and the brake disc is 10-20mm.

[0014] When a wind turbine is running, the hub drives the main shaft to rotate. The rotation is accelerated by a gearbox, and the high-speed shaft transmits power to the generator to produce electricity. The method for online monitoring of broken connecting bolts between the hub and the main shaft using the monitoring device provided in this application is as follows:

[0015] When the wind turbine is running, the connecting flange rotates synchronously with the main shaft. Whenever the connecting bolt moves to the detection position of the first detection element, the first detection element generates a high potential, thereby enabling the counting of the connecting bolts passing through the first detection element per unit time. The number of high potentials detected by the first detection element per minute is M1.

[0016] Similarly, the brake disc rotates synchronously with the high-speed shaft. Whenever the teeth of the brake disc pass the detection position of the second detection element, the second detection element generates a high potential, thereby enabling the counting of the brake disc teeth passing through the second detection element per unit time. The number of high potentials detected by the second detection element per minute is M2.

[0017] Furthermore, the gearbox has an acceleration ratio of i, and the number of teeth on the brake disc is N2; when the connecting bolts are in good condition, the total number of connecting bolts on the connecting flange is N1.

[0018] We can obtain that the apparent speed of the main spindle r1 = M1 ÷ N1, and the apparent speed of the high-speed shaft r2 = M2 ÷ N2.

[0019] When the connecting bolts between the hub and the spindle are intact, r1 = r2 ÷ i; when the connecting bolts between the hub and the spindle are broken or detached, the number of high potentials M1 measured per minute by the first detection element will decrease, therefore, r1 <r2÷i。

[0020] Therefore, by comparing the values ​​of r1 and r2÷i, it can be determined whether the connecting bolts between the hub and the main shaft are broken or detached, thus enabling online monitoring and diagnosis of bolt breakage.

[0021] Furthermore, the first detection element is configured as one or more, and the second detection element is configured as one or more.

[0022] When one of the first or second detection elements fails, the other first and second detection elements can continue to function normally, which helps to avoid false alarms caused by the failure of the first or second detection element, thereby improving the accuracy and stability of monitoring.

[0023] Furthermore, it also includes a protective box and a signal processing circuit disposed inside the protective box, wherein the signal processing circuit is electrically connected to the first detection element and the second detection element respectively.

[0024] The signal processing circuit is used to amplify, filter, and analyze the signals acquired by the first and second detection devices; the protective box is used to protect the signal processing circuit.

[0025] Furthermore, a main bearing housing is fixedly installed in the engine compartment, the main shaft is rotatably installed in the main bearing housing, and the first detection element is fixedly installed on the main bearing housing.

[0026] Furthermore, the second detection element is fixedly mounted on the gearbox.

[0027] In summary, this application includes the following beneficial technical effects:

[0028] The device provided in this application can realize online monitoring of the status of the connecting bolts between the hub and the main shaft, thereby promptly detecting situations where the connecting bolts are broken or detached, and ensuring the safe operation of the unit. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the overall structure of a monitoring device for the fracture of hub connecting bolts of a wind turbine generator set according to an embodiment of this application;

[0030] Figure 2 This embodiment of the application is mainly used to show the structural diagram of the connecting flange and the first detection element, wherein (a) is the front view of the connecting flange and (b) is the side view of the connecting flange;

[0031] Figure 3 This embodiment of the application is mainly used to show the structural diagram of the brake disc and the second detection component, wherein (a) is the front view of the brake disc and (b) is the side view of the brake disc.

[0032] Reference numerals: 1. Blade; 2. Hub; 3. Connecting flange; 4. Connecting bolt; 5. Main shaft; 6. Main bearing housing; 7. First inspection piece; 8. Gearbox; 9. Second inspection piece; 10. High-speed shaft; 11. Brake disc; 12. Gear; 13. Generator; 14. Protective box. Detailed Implementation

[0033] The following is in conjunction with the appendix Figure 1-3 This application will be described in further detail.

[0034] This application discloses a monitoring device for the fracture of hub connecting bolts in a wind turbine generator set. (Refer to...) Figure 1 and Figure 2 The wind turbine generator set includes a nacelle (not shown in the figure) and a main bearing housing 6 fixedly installed in the nacelle. The main bearing housing 6 is rotatably connected to the main shaft 5 via bearings. The main shaft 5 is rotatably installed inside the nacelle. One end of the main shaft 5 is connected to a hub 2 via a connecting flange 3 and multiple connecting bolts 4. Multiple blades 1 are fixed to the periphery of the hub 2. Both the hub 2 and the blades 1 are located outside the nacelle.

[0035] Reference Figure 1 and Figure 3 A generator 13 and a gearbox 8 are fixedly installed in the engine compartment. The input end of the gearbox 8 is connected to the main shaft 5, and the output end of the gearbox 8 is connected to a high-speed shaft 10, which is connected to the input end of the generator 13. A brake disc 11 is coaxially connected to the high-speed shaft 10. In this embodiment, multiple teeth 12 are evenly arranged on the periphery of the brake disc 11 to facilitate manual rotation using gear tools.

[0036] When the wind turbine is running, the wind drives the blades 1, causing the hub 2 to rotate. The main shaft 5 rotates synchronously with the hub 2. After being accelerated by the gearbox 8, the high-speed shaft 10 rotates at high speed and transmits power to the generator 13 to generate electricity. During this process, the connecting flange 3 rotates synchronously with the main shaft 5, and the brake disc 11 rotates synchronously with the high-speed shaft 10.

[0037] Reference Figure 1 The monitoring device includes a first detection element 7 and a second detection element 9. Specifically, both the first detection element 7 and the second detection element 9 are voltage-type proximity sensors. The first detection element 7 is fixedly mounted on the housing of the main bearing seat 6 and can be fixed using a mounting bracket. The second detection element 9 is fixedly mounted on the housing of the gearbox 8 and can be fixed using a mounting bracket.

[0038] Reference Figure 1 and Figure 2 The orientation of the first detection element 7 is parallel to the axial direction of the connecting flange 3, and the first detection element 7 is oriented toward the movement trajectory of the connecting bolt 4. The distance between the first detection element 7 and the connecting bolt 4 is 10-20mm.

[0039] Reference Figure 1 and Figure 3 The orientation of the second detection element 9 is parallel to the axial direction of the brake disc 11, and the movement trajectory of the second detection element 9 toward the tooth 12 is 10-20mm.

[0040] Reference Figure 1 The monitoring device also includes a protective housing 14 and a signal processing circuit housed within the protective housing 14. The signal processing circuit is electrically connected to the first detection element 7 and the second detection element 9 via transmission cables. The signal processing circuit amplifies, filters, and analyzes the signals collected by the first detection element 7 and the second detection element 9, and calculates and determines whether the connecting bolt 4 has broken or fallen off. The protective housing 14 is made of stainless steel and has good waterproof, dustproof, and impact-resistant properties, serving to protect the signal processing circuit.

[0041] The above-mentioned monitoring device for the fracture of the hub connecting bolt of a wind turbine generator set is used to monitor the fracture of the connecting bolt 4 between the hub 2 and the main shaft 5 online. The specific method is as follows:

[0042] When the wind turbine is running, the connecting flange 3 rotates synchronously with the main shaft 5. Whenever the connecting bolt 4 moves to the detection position of the first detection element 7, the first detection element 7 generates a high potential, thereby enabling the counting of the connecting bolts 4 passing through the first detection element 7 per unit time. The number of high potentials detected by the first detection element 7 per minute is M1.

[0043] Similarly, the brake disc 11 rotates synchronously with the high-speed shaft 10. Whenever a tooth 12 of the brake disc 11 passes the detection position of the second detection element 9, the second detection element 9 generates a high potential, thereby enabling the counting of the brake disc 11 teeth 12 passing through the second detection element 9 per unit time. The number of high potentials detected by the second detection element 9 per minute is M2.

[0044] Furthermore, the speed increase ratio of the gearbox 8 is i, and the number of teeth on the brake disc 11 is N2; when the connecting bolts 4 are in good condition, the total number of connecting bolts 4 on the connecting flange 3 is N1.

[0045] We can obtain that the apparent speed of spindle 5 is r1 = M1 ÷ N1, and the apparent speed of high-speed shaft 10 is r2 = M2 ÷ N2.

[0046] When the connecting bolt 4 between the hub 2 and the main shaft 5 is intact, r1 = r2 ÷ i; when the connecting bolt 4 is broken or detached, the number of high potentials M1 detected by the first detection element 7 per minute will decrease, therefore, r1 <r2÷i。

[0047] Therefore, by comparing the values ​​of r1 and r2÷i, it can be determined whether the connecting bolt 4 has broken or fallen off, thus realizing online monitoring and diagnosis of the breakage of the connecting bolt 4.

[0048] When the apparent rotational speed r1 of the main shaft 5 is less than 3 revolutions per minute, the unit is considered to be in a shutdown state, and the system does not perform data acquisition and calculation.

[0049] The first detection element 7 can be set to one or more, and the second detection element 9 can also be set to one or more. The purpose of setting multiple first detection elements 7 or second detection elements 9 is that when one of the first detection elements 7 or second detection elements 9 is damaged, the other first detection elements 7 and second detection elements 9 can continue to work normally, which helps to avoid false alarms caused by the damage of the first detection elements 7 or second detection elements 9, thereby improving the accuracy and stability of monitoring.

[0050] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A monitoring device for the fracture of hub connecting bolts in a wind turbine generator set, characterized in that: The wind turbine generator set includes a nacelle and a main shaft rotatably mounted in the nacelle. The main shaft is connected to a hub via a connecting flange and multiple connecting bolts. The nacelle houses a generator and a gearbox. The input end of the gearbox is connected to the main shaft, and the output end of the gearbox is connected to a high-speed shaft, which is connected to the input end of the generator. A brake disc is coaxially connected to the high-speed shaft, and multiple teeth are evenly arranged on the circumference of the brake disc. The monitoring device includes: The first detection element is fixedly installed in the cabin. The movement trajectory of the first detection element toward the connecting bolt is used to detect the number of connecting bolts passing the first detection element per unit time when the connecting flange rotates. The second detection element is fixedly installed in the engine compartment. The movement trajectory of the second detection element toward the teeth is used to detect the number of teeth passing through the second detection element per unit time when the brake disc rotates.

2. The monitoring device for the fracture of hub connecting bolts in a wind turbine generator set according to claim 1, characterized in that: Both the first detection element and the second detection element are proximity sensors.

3. The monitoring device for the fracture of hub connecting bolts in a wind turbine generator set according to claim 2, characterized in that: Both the first detection element and the second detection element are voltage-type proximity sensors.

4. The monitoring device for the fracture of hub connecting bolts in a wind turbine generator set according to claim 1, characterized in that: The orientation of the first detection element is parallel to the axial direction of the connecting flange.

5. The monitoring device for the fracture of hub connecting bolts in a wind turbine generator set according to claim 4, characterized in that: The orientation of the second detection element is parallel to the axial direction of the brake disc.

6. The monitoring device for the fracture of hub connecting bolts in a wind turbine generator set according to claim 5, characterized in that: The distance between the first detection component and the connecting bolt is 10-20mm, and the axial distance between the second detection component and the brake disc is 10-20mm.

7. The monitoring device for the fracture of hub connecting bolts in a wind turbine generator set according to claim 1, characterized in that: The first detection element is configured as one or more, and the second detection element is configured as one or more.

8. The monitoring device for the fracture of hub connecting bolts in a wind turbine generator set according to claim 1, characterized in that: It also includes a protective box and a signal processing circuit disposed inside the protective box, wherein the signal processing circuit is electrically connected to the first detection element and the second detection element respectively.

9. The monitoring device for the fracture of hub connecting bolts in a wind turbine generator set according to claim 1, characterized in that: A main bearing housing is fixedly installed in the engine compartment, the main shaft is rotatably mounted in the main bearing housing, and the first detection element is fixedly mounted on the main bearing housing.

10. The monitoring device for the fracture of hub connecting bolts in a wind turbine generator set according to claim 1, characterized in that: The second detection element is fixedly mounted on the gearbox.

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