A fan tower pre-stressed anchor bolt loosening alarm monitoring method and device

Abstract

The application provides a fan tower prestressed anchor bolt loosening alarm monitoring method and device, comprising: obtaining vibration signals of the fan tower under different wind speed sections through a vibration sensor and a vibration spectrum analysis system; analyzing the vibration signals to establish a vibration low-frequency component database; comparing the integral of the low-frequency component in the vibration low-frequency component database with a set standard, and when the integral of the low-frequency component exceeds the set standard, an alarm is given; if the alarm is detected, a tracking analysis and offline monitoring flow is started to determine a first loosening position; the bolts at the first loosening position are photographed to obtain bolt detection images with preset markers; the preset markers are used to indicate whether the bolts are loosened; it is judged whether the preset markers in the bolt detection images are displaced, and if yes, it is determined that the bolts corresponding to the displaced preset markers are loosened, and the specific positions of the loosened bolts are determined; and the loosened bolts are found in time, and safety risks are reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wind turbine tower monitoring, in particular to a wind turbine tower prestressed anchor bolt loosening alarm monitoring method and device. BACKGROUND

[0002] With large-scale development and utilization of on-road wind energy resources, wind turbine generators are developing at a faster pace towards high towers and large diameters. The current mainstream hub height has reached 120, 140m, or even 160m. Wind turbines at this height level bear a large difference in forces under different wind speeds, and the load influence caused by the rotation of the three blades of the wind turbine, so the tower bears unstable impact load. The bolts connecting each section of the tower are long-term operated under the action of such variable load stress, and the phenomenon of bolt loosening is relatively serious, and even fatigue fracture may occur, which has a large tower collapse safety hazard and is easy to cause serious safety accidents and economic losses. Therefore, it is necessary and critical to monitor the bolt state in real time, timely find loose bolts, and timely dispose.

[0003] Therefore, the present application provides a wind turbine tower prestressed anchor bolt loosening alarm monitoring method and device to timely find loose bolts and reduce safety risks. SUMMARY

[0004] The purpose of the present application is to provide a wind turbine tower prestressed anchor bolt loosening alarm monitoring method, comprising: acquiring vibration signals of a wind turbine tower under different wind speed sections through a vibration sensor and a vibration spectrum analysis system; analyzing the vibration signals to establish a vibration low-frequency component database; comparing the low-frequency component integral quantity in the vibration low-frequency component database with a set standard, and when the low-frequency component integral quantity exceeds the set standard, an alarm is given; if an alarm is detected, a tracking analysis and offline monitoring flow is started to determine a first loosening position; the bolts at the first loosening position are photographed to obtain a bolt detection image with a preset mark; the preset mark is used to indicate whether the bolts are loose; it is judged whether the preset mark in the bolt detection image is displaced, and if so, it is determined that the bolts corresponding to the displaced preset mark are loose, and the specific position of the loose bolts is determined.

[0005] Further, after the wind turbine tower is installed, the preset mark is arranged on the connecting layer of the bolts and the wind turbine tower.

[0006] Further, the preset mark includes a first part and a second part, the first part is located on the bolt, and the second part is located on the connecting layer of the wind turbine tower; by judging whether the first part and the second part of the preset mark in the bolt detection image are continuous, it is determined whether the bolt is displaced.

[0007] Further, the vibration signals of the fan tower at different wind speed sections are obtained by determining a yaw "0" angle part as the front of the fan tower, installing a vibration sensor at an edge position of the yaw engaging tooth on the front of the fan tower, and installing the vibration spectrum analysis system in the nacelle of the fan tower, and connecting the vibration sensor through a wired or wireless mode to obtain the vibration signals.

[0008] Further, the alarm is a pre-warning to the operation and maintenance personnel, prompting offline maintenance of the bolt state of the fan tower.

[0009] Further, the determination of the first loose part includes tracking the vibration signals, vibration spectrum and wind speed and direction, determining the stress condition of the fan tower, analyzing the relationship between the vibration signals, the vibration spectrum and the wind speed and direction, determining a plurality of potential wind direction sectors and tower sections with bolt loosening, stopping the fan, detecting the potential wind direction sectors and tower sections respectively, and determining the loosened wind direction sectors and tower sections.

[0010] Further, a plurality of camera devices are installed on the inner wall of the fan tower, each of which captures bolts within a certain range; the capturing of the bolts of the first loose part includes determining the capturing range of the first loose part, determining the corresponding camera device based on the capturing range, and obtaining the bolt detection image captured by the camera device.

[0011] Further, the camera device rotates by a preset angle to the right direction of the circumference of the fan tower every preset time to realize the capturing of the range.

[0012] Further, it further includes collecting vibration signals at different wind speed sections and analysis results given by the vibration spectrum analysis system, and determining 33 wind speed sections according to the rule that when the wind speed is less than or equal to 30 m / s, the wind speed section interval is 1 m / s; when the wind speed is greater than 30 m / s, the wind speed section interval is 2 m / s.

[0013] The purpose of the present application is to provide a fan tower prestressed anchor bolt loosening alarm monitoring device, comprising a vibration sensor, a vibration spectrum analysis system, a vibration low-frequency component database establishment module, an alarm module, an analysis module, a camera device and a judgment module; the vibration sensor is used to obtain the vibration signal of the fan tower under different wind speed sections; the vibration spectrum analysis system is used to give the analysis result; the vibration low-frequency component database establishment module is used to analyze the vibration signal and establish a vibration low-frequency component database; the alarm module is used to compare the low-frequency component integral in the vibration low-frequency component database with the set standard, and when the low-frequency component integral exceeds the set standard, an alarm is given; the analysis module is used to start tracking analysis and offline monitoring flow if an alarm is detected, and determine the first loosening position; the camera device is used to take pictures of the bolts of the first loosening position, and obtain bolt detection images with preset marks; the preset marks are used to indicate whether the bolts are loose; the judgment module is used to judge whether the preset marks in the bolt detection images are displaced, and if so, determine that the bolts corresponding to the displaced preset marks are loose, and determine the specific position of the loose bolts.

[0014] The technical scheme of the embodiment of the present application has at least the following advantages and beneficial effects:

[0015] The present application can be systematically applied to the connecting bolts of the wind turbine tower, especially the connecting bolts of high towers and super-high towers, by monitoring the vibration signal, can monitor the bolt state in real time, find the bolt loosening in time, and send a warning to the relevant personnel; can better play a protective effect, effectively ensure the safe operation of the wind farm, and reduce the economic loss caused by accidents.

[0016] The present application can quickly and effectively detect whether the bolts are loose by judging whether the marks of each bolt and the tower connecting layer at the fixed position are displaced, and the detection method is simple and practical, can efficiently detect whether a large number of bolts are loose, and the related equipment has a low cost, is beneficial to users to save costs and create higher value, and meets the actual needs. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 An exemplary flow chart of a fan tower prestressed anchor bolt loosening alarm monitoring method is provided for some embodiments of the present application;

[0018] Figure 2 An exemplary schematic diagram of a fan tower prestressed anchor bolt loosening alarm monitoring device is provided for some embodiments of the present application. DETAILED DESCRIPTION

[0019] To make the purposes, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. The components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0020] Figure 1 An exemplary flowchart of a wind turbine tower prestressed anchor bolt loosening alarm monitoring method provided by some embodiments of the present application is shown in FIG. 1. As shown in FIG. 1, the flowchart 100 includes the following steps. Figure 1

[0021] In step 110, the vibration signals of the wind turbine tower at different wind speed segments are acquired by a vibration sensor and a vibration spectrum analysis system.

[0022] The vibration signals can represent the vibration condition of the wind turbine tower. In some embodiments, the vibration sensor is mainly a vibration speed sensor, and wireless connection or wired connection is selected according to the site needs; the wireless connection means that a vibration signal wireless sending device is installed on the speed sensor, and the signals are sent to the nacelle by wireless mode; the wired connection directly transmits the signals to the nacelle by signal lines at the installation position of the vibration sensor.

[0023] In some embodiments, the method further includes: collecting the vibration signals at different wind speed segments and the analysis results given by the vibration spectrum analysis system, and determining 33 wind speed segments according to the rule that the wind speed segment interval is 1 m / s when the wind speed is less than or equal to 30 m / s, and the wind speed segment interval is 2 m / s when the wind speed is greater than 30 m / s.

[0024] In some embodiments, the acquisition of the vibration signals of the wind turbine tower at different wind speed segments includes: determining a yaw "0" angle part as the front face of the wind turbine tower; installing a vibration sensor at the edge position of the yaw engaging tooth on the front face of the wind turbine tower; and installing the vibration spectrum analysis system in the nacelle of the wind turbine tower, and connecting the vibration sensor by wired or wireless mode to acquire the vibration signals. The vibration sensor is arranged at the flange plate connection of the tower, and the front face of the wind turbine is the face of the yaw "0" angle part directly facing the hub.

[0025] In step 120, the vibration signals are analyzed, and a vibration low-frequency component database is established.

[0026] In some embodiments, the vibration sensor can be installed on a normal wind turbine to measure the vibration frequency at different wind speeds for three years, and the vibration frequency is recorded into the system as the vibration low-frequency component database. When the vibration frequency of the wind turbine is greater than the standard frequency set by the vibration low-frequency component database, an alarm is issued.

[0027] ​Step 130, compare the low-frequency component integral quantity in the vibration low-frequency component database with a set standard, and when the low-frequency component integral quantity exceeds the set standard, an alarm is given. The set standard of the low-frequency integral quantity is set according to 3 years of basic data, and the integral quantity is a process of measuring vibration frequency.

[0028] In some embodiments, the alarm is a pre-warning given to an operation and maintenance personnel, prompting offline maintenance of the bolt state of the wind turbine tower.

[0029] Step 140, if an alarm is detected, a tracking analysis and offline monitoring flow is started to determine a first loosening position. The tracking analysis means that when the vibration device gives an alarm, it is necessary to check whether the bolt is loose and whether the torque value meets the requirements to verify the bolt tightness in real time. The offline monitoring flow means that professional instruments are used to check and test to determine whether the equipment is normal.

[0030] In some embodiments, the determination of the first loosening position comprises tracking the vibration signal, vibration spectrum and wind speed and direction, determining the stress condition of the wind turbine tower, and analyzing the relationship between the vibration signal, the vibration spectrum and the wind speed and direction; determining a plurality of potential wind direction sectors and tower sections where the bolt is loose; stopping the wind turbine; detecting the potential wind direction sectors and tower sections respectively; and determining the loose wind direction sector and tower section. For example, a pre-warning is given according to the discrimination result of the bolt state of the wind turbine tower; when the low-frequency component integral quantity of the vibration exceeds the determined vibration low-frequency component integral quantity standard; a pre-warning is given to the operation and maintenance personnel; it is prompted that the bolt state of the tower should be maintained offline, and after receiving the pre-warning given by the system; the vibration signal, vibration spectrum and wind speed and direction are tracked; the stress condition of the tower is determined, and the relationship between the vibration signal, vibration spectrum and wind speed and direction is analyzed; a plurality of potential wind direction sectors and tower sections where the bolt is loose are determined; the wind turbine is stopped; the wind direction sectors and tower sections are detected respectively; and the approximate position of the loose bolt is determined.

[0031] Step 150, the bolts at the first loosening position are photographed to obtain a bolt detection image with a preset mark. The preset mark is used to indicate whether the bolt is loose. Each bolt has a preset mark at a fixed position of the tower connection layer. The tower connection layer refers to the wind turbine flange, which is the place where the two sections of the tower are connected by the bolts. The bolt detection image is a photograph of whether the torque line of the bolt head and the flange is on the same straight line.

[0032] In some embodiments, the wind turbine tower inner wall is provided with a plurality of cameras, each of which captures bolts within a certain range; the bolt in the first loosening part is captured by: determining the camera range in which the first loosening part is located; determining the corresponding camera based on the camera range; and obtaining the bolt detection image captured by the camera. For example, the camera for capturing the bolt image is fixed on the inner wall of the tower by a magnetic seat, and three cameras are installed on the inner wall of the tower (for example, each camera captures a range of 120 degrees), and each camera captures the mark on the bolt within the corresponding range.

[0033] In some embodiments, the camera rotates by a preset angle to the right side of the circumference of the wind turbine tower every preset time to realize the range. The preset angle refers to the angle of rotation of the camera. For example, each of the three cameras is responsible for an angle of 120 degrees, which is one third of the circumference, and the camera rotates by 10 degrees to the right side of the circumference every 10 seconds to realize the range.

[0034] In some embodiments, the camera is a zoom camera, which can automatically adjust the focal length according to the position of the bolt to make the preset mark captured more clearly.

[0035] In some embodiments, after the wind turbine tower is installed, the preset mark is provided on the connecting layer between the bolt and the wind turbine tower.

[0036] In some embodiments, the preset mark includes a first part and a second part, the first part is located on the bolt, and the second part is located on the connecting layer of the wind turbine tower; whether the bolt has been displaced is determined by judging whether the first part and the second part of the preset mark in the bolt detection image are continuous. For example, draw a straight line extending from the bolt to the connecting layer, and when the bolt head torque line and the base line are misaligned and not on the same straight line, it is determined that displacement has occurred.

[0037] Step 160, determine whether the preset mark in the bolt detection image is displaced, if so, determine that the bolt corresponding to the displaced preset mark is loose, and determine the specific part of the bolt that is loose.

[0038] When the bolt head torque line and the base line at the connecting part of the tower are not on the same straight line, it is determined that loosening has occurred.

[0039] Figure 2 An exemplary schematic diagram of a wind turbine tower prestressed anchor bolt loosening alarm monitoring device is provided for some embodiments of the present application. As shown in Figure 2As shown, it comprises a vibration sensor 210, a vibration spectrum analysis system 220, a vibration low-frequency component database establishment module 230, an alarm module 240, an analysis module 250, a camera 260 and a judgment module 270.

[0040] The vibration sensor 210 is used to acquire vibration signals of the fan tower under different wind speed sections. For more information about the vibration sensor 210, see Figure 1 and the related description.

[0041] The vibration spectrum analysis system 220 is used to give the analysis results. For more information about the vibration spectrum analysis system 220, see Figure 1 and the related description.

[0042] The vibration low-frequency component database establishment module 230 is used to analyze the vibration signals and establish a vibration low-frequency component database. For more information about the vibration low-frequency component database 230, see Figure 1 and the related description.

[0043] The alarm module 240 is used to compare the low-frequency component integral quantity in the vibration low-frequency component database with a set standard and give an alarm when the low-frequency component integral quantity exceeds the set standard. For more information about the alarm module 240, see Figure 1 and the related description.

[0044] The analysis module 250 is used to start tracking analysis and offline monitoring flow and determine the first loosening position if an alarm is detected. For more information about the analysis module 250, see Figure 1 and the related description.

[0045] The camera 260 is used to take pictures of the bolts of the first loosening position and obtain bolt detection images with preset marks; the preset marks are used to indicate whether the bolts are loosened. For more information about the camera 260, see Figure 1 and the related description.

[0046] The judgment module 270 is used to judge whether the preset marks in the bolt detection images are displaced, and if so, determine that the bolts corresponding to the displaced preset marks are loosened and determine the specific positions of the loosened bolts. For more information about the judgment module 270, see Figure 1 and the related description.

[0047] The above is only the preferred embodiment of the present application and is not used to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A wind turbine tower prestressed anchor loosening alarm monitoring method, characterized in that: include: Vibration sensors and a vibration spectrum analysis system are used to obtain vibration signals of the wind turbine tower at different wind speeds, including: Determine the yaw angle "0" position as the front of the wind turbine tower; A vibration sensor is installed at an edge of a yaw meshing tooth selected on the front side of the wind turbine tower; The vibration spectrum analysis system is installed in the nacelle of the wind turbine tower and is connected to the vibration sensor via a wired or wireless method to obtain the vibration signal; Analyzing the vibration signal and establishing a vibration low-frequency component database; comparing the integrated amount of the low-frequency component in the vibration low-frequency component database with a set standard, and issuing an alarm when the integrated amount of the low-frequency component exceeds the set standard; If an alarm is detected, tracking analysis and offline monitoring are initiated to determine the first loose location. Tracking analysis means regularly checking the tightness of bolts when the vibration equipment issues an alarm. Offline monitoring means using instrument inspection and testing to determine whether the equipment is normal, including: Tracking the vibration signal, vibration spectrum, and wind speed and direction; Determining the stress condition of the wind turbine tower, and analyzing the relationship between the vibration signal, the vibration spectrum, and the wind speed and direction; Identify several potential wind direction sectors and tower sections where bolt loosening may occur; Shut down the wind turbine; and inspect the potential wind direction sectors and tower sections respectively; Identify loose wind sectors and tower sections; photographing the bolt at the first loose location to obtain a bolt detection image with a preset mark; the preset mark is used to indicate whether the bolt is loose; after the wind turbine tower is installed, setting the preset mark on the connection layer between the bolt and the wind turbine tower; the preset mark includes a first part and a second part, the first part is located on the bolt, and the second part is located on the connection layer of the wind turbine tower; determining whether the bolt has been displaced by determining whether the first part and the second part of the preset mark in the bolt detection image are continuous; It is determined whether the preset mark in the bolt detection image is displaced. If so, it is determined that the bolt corresponding to the displaced preset mark is loose, and the specific location where the bolt is loose is determined.

2. The wind turbine tower prestressed anchor loosening alarm monitoring method according to claim 1 is characterized in that: The alarm is used to issue an early warning to the operation and maintenance personnel, prompting them to perform offline maintenance on the bolt status of the wind turbine tower.

3. The wind turbine tower prestressed anchor loosening alarm monitoring method according to claim 1 is characterized in that: A plurality of camera devices are installed on the inner wall of the wind turbine tower, and each of the camera devices photographs bolts within a certain range; photographing the bolts at the first loose position includes: determining a shooting range where the first loose part is located; determining a corresponding camera device based on the shooting range; Obtain a bolt detection image captured by the camera device.

4. The wind turbine tower prestressed anchor loosening alarm monitoring method according to claim 3 is characterized in that: The camera device rotates toward the right side of the circumference of the wind turbine tower by a preset angle at every preset time.

5. The wind turbine tower prestressed anchor loosening alarm monitoring method according to claim 1 is characterized in that: Also includes: The vibration signals under different wind speed segments and the analysis results given by the vibration spectrum analysis system were collected. 33 wind speed segments were determined according to the rule that when the wind speed is less than or equal to 30 m / s, the wind speed segment interval is 1 m / s; when the wind speed is greater than 30 m / s, the wind speed segment interval is 2 m / s.

6. A wind turbine tower prestressed anchor loosening alarm monitoring device using the wind turbine tower prestressed anchor loosening alarm monitoring method according to any one of claims 1 to 5, characterized in that: It includes a vibration sensor, a vibration spectrum analysis system, a vibration low-frequency component database establishment module, an alarm module, an analysis module, a camera device and a judgment module; The vibration sensor is used to obtain vibration signals of the wind turbine tower at different wind speed ranges; The vibration spectrum analysis system is used to provide analysis results; The vibration low-frequency component database establishment module is used to analyze the vibration signal and establish a vibration low-frequency component database; The alarm module is used to compare the integrated amount of the low-frequency component in the vibration low-frequency component database with a set standard, and to issue an alarm when the integrated amount of the low-frequency component exceeds the set standard; The analysis module is used to start tracking analysis and offline monitoring flow if an alarm is detected to determine the first loose location; tracking analysis means that when the vibration equipment issues an alarm, the bolt tightness is regularly checked; offline monitoring flow means that the equipment is checked and tested by instruments to determine whether it is normal; The camera device is used to photograph the bolt at the first loose position to obtain a bolt detection image with a preset mark; the preset mark is used to indicate whether the bolt is loose; The judgment module is used to judge whether the preset mark in the bolt detection image is displaced. If so, it is determined that the bolt corresponding to the displaced preset mark is loose, and the specific location of the bolt that is loose is determined.

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