Wind turbine generator concrete tower monitoring method based on target image recognition

Abstract

The invention discloses a wind turbine generator concrete tower drum monitoring method based on target image recognition, which comprises the following steps of: arranging a group of targets side by side at the middle part or the middle lower part of each vertical splicing seam of each section of concrete tower drum, and arranging a high-definition camera on a tower drum platform at the lower part of each group of targets and at a position close to the center of the tower drum platform, a high-definition camera is arranged below each group of targets, lenses of the high-definition cameras directly face the group of targets and can capture all images of the group of targets, and all the high-definition cameras collect and shoot image data information of the targets above the respective lenses in real time; the acquired image data information is transmitted to the central processing unit through the data acquisition and transmission module; by matching with image analysis and processing of the central processing unit, the deformation amount and the moving speed of the horizontal axis and the deflection angle and the deflection angular speed of the longitudinal axis at the splicing seam of the tower drum can be clearly monitored, and corresponding safety early warning can be given out when data are abnormal.

Description

Technical Field

[0001] The present invention relates to the technical field of wind turbine tower monitoring, and in particular to a method and device for monitoring a wind turbine concrete tower based on target image recognition. Background Art

[0002] A wind turbine is a device that converts wind energy into mechanical energy and then electrical energy by rotating its impeller against the wind. In order to increase the height of wind turbines and improve their power generation capacity, the height of some wind turbines has reached more than 140 meters. In order to ensure the strength, durability and economy of the wind turbine tower, the hybrid tower structure with a lower concrete tower and an upper steel tower is increasingly being used. The concrete tower of a wind turbine is generally divided into multiple sections, each of which is composed of two or more pieces of concrete tower segments. The tower is one of the key load-bearing components of a wind turbine. Maintaining the tower in a normal and safe state is the basic guarantee for the normal operation of a wind turbine. If the inclination, deformation, vibration and other problems of the wind turbine tower reach a certain level, it may lead to a serious accident of tower collapse. There are many joints in the concrete tower segments of a wind turbine, which are fragile parts that are prone to problems and need to be paid special attention to.

[0003] In recent years, online fault monitoring systems have been increasingly used in wind turbines, among which state monitoring based on target image recognition technology is an important technical direction. With the continuous advancement of image recognition technology, the hardware cost of image recognition is getting lower and lower, and the monitoring accuracy and reliability based on target image recognition technology are getting higher and higher. CN119195994A discloses a method and device for monitoring the state of a wind turbine tower based on target image recognition. In this patent, a target is installed on the lower surface of the top platform of each layer of the tower near the outer edge, and a high-definition camera is set on the bottom platform of the tower below each target. The high-definition camera lens faces the target upward, and cooperates with the image analysis and processing of the central processor to clearly analyze the displacement, deflection angle, displacement speed and deflection angular velocity of the target position of each layer of the tower platform, accurately monitor the tower state, and realize safety warning. However, the above patent is only for conventional wind turbine towers, and cannot be used for monitoring concrete towers. Since there are many segmented connection seams in the concrete tower of a wind turbine, and abnormal displacement is more likely to occur at the vertical connection seams, it needs to be paid special attention. Therefore, how to use target image recognition technology to monitor the status of wind turbine hybrid tower is a technical problem that needs to be solved urgently. Summary of the invention

[0004] In order to address the deficiencies in the prior art, the present invention provides a wind turbine concrete tower monitoring method based on target image recognition, wherein a group of targets are arranged side by side in the middle or lower middle position of each vertical joint of each section of the concrete tower, and a high-definition camera is arranged on the bottom platform of the tower below each group of targets. The lens of the high-definition camera is facing upward toward the group of targets, and the image analysis and processing of the central processing unit can clearly analyze the displacement, deflection angle, displacement speed and deflection angular velocity of the target position at the joint of each layer of the tower, accurately monitor the state of the concrete tower, and realize safety warning.

[0005] The technical solution adopted to achieve the above-mentioned purpose of the present invention is: A wind turbine concrete tower monitoring method based on target image recognition, the target comprising a lampshade and a group of wicks and a power supply inside the lampshade, the lampshade comprising a bottom plate, a side plate on the side of the bottom plate and a panel on the top of the bottom plate, the panel being provided with a hollow light-transmitting area; the light-transmitting area is a cross-shaped light-transmitting area, the longitudinal axis light-transmitting area length of the cross-shaped light-transmitting area is greater than the transverse axis light-transmitting area length, and a circular non-light-transmitting area is provided at the center of the cross-shaped light-transmitting area; The method comprises the following steps: (1) A group of targets shall be arranged side by side in the middle or lower middle part of each vertical joint of each section of the concrete tower. Each group of targets shall consist of two targets. The two targets shall be arranged symmetrically on both sides of the joint of the concrete tower. The two targets shall be at the same height from the bottom platform of the section of the tower and at the same distance from the joint. (2) A high-definition camera is installed on the tower platform below each group of targets, near the center of the tower platform. A high-definition camera is installed below each group of targets. The lens of the high-definition camera is facing the group of targets and can capture all images of the group of targets. (3) Number the concrete tower, targets and high-definition cameras. The serial numbers of each concrete tower section from bottom to top are recorded as 1, 2, 3... i ....... n, where n indicates that there are n concrete tower sections in total; the j-th high-definition camera on the bottom platform of the i-th tower section is marked as the ij-th high-definition camera, 1≤j≤m, where m indicates that the total number of high-definition cameras on the bottom platform of this tower section is m; in each group of targets, the origin, horizontal axis and vertical axis of the left target are marked as O1, X1 and Y1 respectively, and the origin, horizontal axis and vertical axis of the right target are marked as O2, X2 and Y2 respectively; (4) When the wind turbine is in operation, the lamp in the target is powered on and emits light; all high-definition cameras will collect and shoot image data of the target above their respective lenses in real time, and transmit the collected image data to the central processor through the data acquisition and transmission module; (5) The central processor receives the image data information sent by the data acquisition and transmission module, processes and analyzes the received image data information, determines the position and direction of the target based on the grayscale index and shape characteristics of each area in the image; determines the position and angle direction information of the origin, horizontal axis and vertical axis of each target based on the grayscale index and state characteristics of the target's transparent area and non-transparent area; (6) The target orientation when the wind speed is low and the wind turbine has not started working is taken as the quasi-static reference orientation of the target; (7) When the wind turbine is in operation, obtain target image data information according to steps (4) and (5); (8) The central processing unit processes and analyzes the processed target image data information, monitors the deformation and movement speed of the horizontal axis at the tower joint, as well as the deflection angle and deflection angular velocity of the vertical axis, and issues corresponding safety warnings when the data is abnormal.

[0006] Furthermore, an edge of a non-light-transmitting area on the inner surface of the panel adjacent to the light-transmitting area is provided with an inclination angle of ≥30°.

[0007] Furthermore, the bottom plate, side plates and panels outside the light-transmitting area are all made of non-light-transmitting materials, and the outer surfaces are all black.

[0008] Furthermore, the HD camera adopts a high shooting frame rate and is equipped with a wide-angle lens; a base is provided at the bottom of the HD camera, and the HD camera base is fixed to the tower platform by bonding or bolting; the angle between the HD camera body and the base is adjustable, and the pitch angle of the HD camera lens can be adjusted.

[0009] Furthermore, the data acquisition and transmission module can receive image data captured by each high-definition camera, and transmit the received image data to the central processing unit in a wired or wireless manner.

[0010] Furthermore, the central processing unit receives image data information sent by the data acquisition and transmission module, and the image processing software in the central processing unit processes and analyzes the received image data, and identifies the position and direction of the target in the image based on the grayscale index and shape characteristics of each area in the image.

[0011] Furthermore, in step (8), the method for monitoring the transverse axis deformation at the tower joint is as follows: the central processor performs data comparison, and when any of the following conditions exists, it indicates that the deformation at the tower joint taken by the jth high-definition camera on the bottom platform of the i-th tower section is obviously abnormal, and a safety warning of abnormal deformation at the i-th tower joint is issued: | D _ij_x_1 |≥ D _i_x_limit_1 ; | D _ij_x_2 |≥ D _i_x_limit_1 ; | D _ij_x_2 -D _ij_x_1 |≥ D _i_x_limit_2 ; In the above formula, D _ij_x_1 and D _ij_x_2 D is the displacement of the origins of the two targets along the horizontal axis relative to their respective origins in the quasi-static reference position when the wind turbine is in working state, photographed by the jth high-definition camera on the bottom platform of any i-th tower section; _i_x_limit_1 The threshold value for early warning of the absolute value of the displacement of the origin of any target of the i-th tower along the horizontal axis relative to the origin under the quasi-static reference orientation is set; D _i_x_limit_2 A warning threshold is set for the absolute value of the displacement difference of any two adjacent symmetrical target origins on the i-th tower section relative to their respective origins in the quasi-static reference orientation along the horizontal axis.

[0012] Furthermore, the method for monitoring the moving speed at the tower joint in step (8) is as follows: _ij_x_1 , D _ij_x_2 Based on the time interval △t between two adjacent frames of images, calculate D within △t time _ij_x_1 , D _ij_x_2 The change value is divided by the time interval △t to obtain the moving speed V of the two target origins along the horizontal axis. _ij_x_1_△t and V _ij_x_2_△t The central processor compares the data. If any of the following conditions exists, it indicates that the moving speed of the joint captured by the jth high-definition camera on the bottom platform of the i-th tower section is obviously abnormal, and a safety warning of abnormal deformation speed of the corresponding tower joint gap is issued: | V _ij_x_1_△t |≥ V _i_x_△t_limit_1 ; | V _ij_x_2_△t |≥ V _i_x_△t_limit_1 ; | V _ij_x_2_△t -V _ij_x_1_△t |≥ V _i_x_△t_limit_2 ; In the above formula, V _i_x_△t_limit_1 V is the warning threshold for the absolute value of the moving speed of any target origin of the i-th tower along the horizontal axis; _i_x_△t_limit_2 A warning threshold is set for the absolute value of the difference in moving speed between any two adjacent symmetrical target origins on the i-th tower section along the horizontal axis.

[0013] Furthermore, in step (8), the method for monitoring the deflection angle of the longitudinal axis at the tower joint is as follows: the central processing unit performs data comparison, and when any of the following conditions exists, it indicates that the change in the longitudinal axis angle at the tower joint taken by the jth high-definition camera on the bottom platform of the i-th tower section is abnormal, and a safety warning of abnormal change in the angle at the i-th tower joint is issued: | A _ij_y_1 |≥ A _i_y_limit_1 ; | A _ij_y_2 |≥ A _i_y_limit_1 ; | A _ij_y_2 - A _ij_y_1 |≥ A _i_y_limit_2 ; In the above formula, A _ij_y_1 and A _ij_y_2 A is the deflection angle of the longitudinal axes of the two targets relative to their respective longitudinal axes in the quasi-static reference position when the wind turbine is in working state, photographed by the jth high-definition camera on the bottom platform of any i-th tower section; _i_x_limit_1 A is the warning threshold for the absolute value of the deflection angle of the longitudinal axis of any target in the i-th tower relative to the longitudinal axis in the quasi-static position; _i_y_limit_2 A warning threshold is set for the absolute value of the difference in deflection angles of any two adjacent symmetrical target longitudinal axes of the i-th tower relative to their respective longitudinal axes in the quasi-static orientation.

[0014] Furthermore, the method for monitoring the deflection angular velocity of the longitudinal axis at the tower joint in step (8) is as follows: _ij_y_1 and A _ij_y_2 Based on the time interval △t between two adjacent frames of images, calculate A within △t time _ij_y_1 , A _ij_y_2 The change value; Divide the change value by the time interval △t to obtain the deflection angular velocity ω of the two target longitudinal axes relative to their respective longitudinal axes in the quasi-static orientation _ij_x_1_△t ,ω _ij_x_2_△t ; The central processor compares the data. When any of the following conditions exists, it indicates that the deflection angular velocity of the tower joint captured by the jth high-definition camera on the bottom platform of the i-th tower section is obviously abnormal, and a safety warning of abnormal deflection angular velocity of the corresponding tower joint gap is issued: |ω _ij_x_1_△t |≥ω _i_x_△t_limit_1 ; |ω _ij_x_2_△t |≥ω _i_x_△t_limit_1 ; |ω _ij_x_2_△t -ω _ij_x_1_△t |≥ω _i_x_△t_limit_2 ; In the above formula, ω_i_x_△t_limit_1 The warning threshold value is set for the absolute value of the deflection angular velocity of the longitudinal axis of any target in the i-th tower relative to the longitudinal axis in the quasi-static position; ω _i_x_△t_limit_2 A warning threshold is set for the absolute value of the difference in the deflection angular velocity of any two adjacent symmetrical target longitudinal axes of the i-th tower relative to their respective longitudinal axes in the quasi-static orientation.

[0015] Compared with the prior art, the wind turbine concrete tower monitoring method based on target image recognition provided by the present invention has the following advantages: (1) The wind turbine concrete tower monitoring method based on target image recognition provided in the present application sets two adjacent and symmetrical targets at the middle or lower middle position of each vertical joint of each section of the concrete tower, and sets a high-definition camera on the tower bottom platform below the two adjacent symmetrical targets. With the help of the central processor image analysis and processing, the deformation, deformation speed, deflection angle, and deflection angular velocity at the joint of each section of the multi-piece concrete tower can be clearly analyzed and monitored, and the tower status can be accurately monitored to achieve safety warning; (2) The longitudinal length of the target's light-transmitting area is greater than its transverse length. When a high-definition camera shoots the target obliquely upward from the tower platform, an easily distinguishable longitudinal length dimension of the target image can be formed, which is convenient for image analysis. (3) The angle between the HD camera body and the base in the present invention is adjustable, and thus the pitch angle of the HD camera lens can be adjusted. When the heights and relative angles between the HD camera and the target are different, the HD camera lens can be made to face the target by adjusting the angle between the HD camera body and the base. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of this specification or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this specification. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 This is a schematic diagram of a wind turbine concrete tower.

[0018] Figure 2 This is a schematic diagram of the target device installation location.

[0019] Figure 3 It is a schematic diagram of the structure of the target device.

[0020] Figure 4 It is a schematic diagram of the structure of the lampshade.

[0021] Figure 5 This is a schematic diagram of the wick arrangement.

[0022] Figure 6 is a schematic diagram of the edge inclination angle.

[0023] Figure 7 It is a schematic diagram of the relationship between the position and direction of the high-definition camera and the target position.

[0024] Figure 8 It is a schematic diagram of the target coordinate axis setting direction.

[0025] Fig. 9 It is a schematic diagram of the structure of a high-definition camera.

[0026] In the figure: 1-target, 11-lampshade, 12-wick, 13-bottom plate, 14-panel, 15-side plate, 16-light-transmitting area, 17-circular non-light-transmitting area, 18-edge, 2-high-definition camera, 21-lens, 22-body, 23-base. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0028] The concrete tower of the wind turbine to be monitored in this application is as follows Figure 1 As shown, the concrete tower of a wind turbine is generally divided into multiple sections, each section is composed of two or more concrete tower segments, and there is a vertical joint between two adjacent concrete tower segments.

[0029] The target 1 used in this application is consistent with the target structure described in CN119195994A. Figure 3 The target device described in this embodiment includes: a lampshade 11 and a group of wicks 12 inside the lampshade. Figure 4 The lampshade includes a bottom plate 13, a side plate 15 on the side of the bottom plate, and a panel 14 on the top of the bottom plate. The bottom plate, the side plate, and the panel outside the light-transmitting area are all made of non-light-transmitting materials, and the outer surface is black. The panel is provided with a hollow light-transmitting area 16. The partial light-transmitting design can effectively improve the contrast between the light-transmitting area and the non-light-transmitting area, which is convenient for image analysis.

[0030] The light-transmitting area is a cross-shaped light-transmitting area, and the horizontal and vertical light-transmitting lengths of the cross-shaped light-transmitting area are different. A circular non-light-transmitting area 17 is provided at the center of the cross-shaped light-transmitting area to facilitate image recognition, and can clearly identify the target x-axis and y-axis, which is convenient for target deflection angle analysis. The internal wick arrangement is as follows Figure 5 shown.

[0031] Reference Figure 6The edge 18 of the non-light-transmitting area of ​​the inner surface of the target lampshade panel, which is adjacent to the light-transmitting area, is provided with a certain inclination angle, and the inclination angle is ≥30°. When the target produces a certain displacement with the tower, the influence of the edge of the non-light-transmitting area of ​​the target on the imaging width of the light-transmitting area caused by the displacement can be avoided, thereby reducing the adverse effect of the deformation of the tower on the quality of the captured image.

[0032] The wind turbine concrete tower monitoring method based on target image recognition provided in this embodiment includes the following steps: (1) A group of targets 1 are arranged side by side in the middle or lower middle of each vertical joint of each concrete tower section. Each group of targets consists of two targets. The two targets are symmetrically arranged on both sides of the concrete tower joint. The two targets are at the same height from the bottom platform of the tower section and at the same distance from the joint. Figure 7 As shown; (2) A high-definition camera 2 is installed on the tower platform below each group of targets, near the center of the tower platform. A high-definition camera 2 is installed below each group of targets 1. The high-definition camera lens is facing the group of targets and can capture all images of the group of targets. Figure 2 and Figure 7 The structure of the high-definition camera used in this embodiment is as follows Fig. 9 As shown, the high-definition camera adopts a high shooting frame rate and is equipped with a wide-angle lens; a base 23 is provided at the bottom of the high-definition camera, and the base 23 of the high-definition camera is fixed to the tower platform by bonding or bolting; the angle between the body 22 of the high-definition camera and the base 23 is adjustable, and the pitch angle of the lens 21 can be adjusted;

[0033] (3) Number the concrete tower, targets and high-definition cameras. The serial numbers of each concrete tower section from bottom to top are marked as 1, 2, 3...i...n, where n means there are n concrete tower sections in total. The j-th high-definition camera on the bottom platform of the i-th tower section is marked as the ij-th high-definition camera, 1≤j≤m, where m means the total number of high-definition cameras on the bottom platform of this tower section is m. In each group of targets, the origin, horizontal axis and vertical axis of the left target are marked as O1, X1 and Y1 respectively, and the origin, horizontal axis and vertical axis of the right target are marked as O2, X2 and Y2 respectively. Figure 8 As shown; (4) When the wind turbine is in operation, the lamp in the target is powered on and emits light; all high-definition cameras will collect and shoot image data information of the target above their respective lenses in real time, and transmit the collected image data information to the central processing unit through the data acquisition and transmission module; the data acquisition and transmission module can receive the image data shot by each high-definition camera, and transmit the received image data to the central processing unit in a wired or wireless manner;

[0034] (5) The central processing unit receives the image data information sent by the data acquisition and transmission module, and the image processing software of the central processing unit processes and analyzes the received image data information, and determines the position and direction of the target based on the grayscale index and shape characteristics of each area in the image; and determines the position and angle orientation information of the origin, horizontal axis and vertical axis of each target based on the grayscale index and state characteristics of the target's transparent area and non-transparent area; (6) The target orientation when the wind speed is low and the wind turbine has not started working is taken as the quasi-static reference orientation of the target; (7) When the wind turbine is in operation, obtain target image data information according to steps (4) and (5); (8) The central processing unit performs the following processing and analysis on the processed target image data information, monitors the deformation and movement speed of the horizontal axis at the tower joint, and the deflection angle and deflection angular velocity of the vertical axis, and issues corresponding safety warnings when the data is abnormal.

[0035] The method for monitoring the horizontal axis deformation at the tower joint in step (8) is as follows: the central processing unit performs data comparison. When any of the following conditions exists, it indicates that the deformation at the tower joint taken by the jth high-definition camera on the bottom platform of the i-th tower section is obviously abnormal, and a safety warning of abnormal deformation at the i-th tower joint is issued: | D _ij_x_1 |≥ D _i_x_limit_1 ; | D _ij_x_2 |≥ D _i_x_limit_1 ; | D _ij_x_2 -D _ij_x_1 |≥ D _i_x_limit_2 ; In the above formula, D _ij_x_1 and D _ij_x_2 D is the displacement of the origins of the two targets along the horizontal axis relative to their respective origins in the quasi-static reference position when the wind turbine is in working state, photographed by the jth high-definition camera on the bottom platform of any i-th tower section; _i_x_limit_1 The threshold value for early warning of the absolute value of the displacement of the origin of any target of the i-th tower along the horizontal axis relative to the origin under the quasi-static reference orientation is set; D _i_x_limit_2 A warning threshold is set for the absolute value of the displacement difference of any two adjacent symmetrical target origins on the i-th tower section relative to their respective origins in the quasi-static reference orientation along the horizontal axis.

[0036] The method for monitoring the moving speed at the tower joint in step (8) is as follows: _ij_x_1 , D _ij_x_2 Based on the time interval △t between two adjacent frames of images, calculate D within △t time_ij_x_1 , D _ij_x_2 The change value is divided by the time interval △t to obtain the moving speed V of the two target origins along the horizontal axis. _ij_x_1_△t and V _ij_x_2_△t The central processor compares the data. If any of the following conditions exists, it indicates that the moving speed of the joint captured by the jth high-definition camera on the bottom platform of the i-th tower section is obviously abnormal, and a safety warning of abnormal deformation speed of the corresponding tower joint gap is issued: | V _ij_x_1_△t |≥ V _i_x_△t_limit_1 ; | V _ij_x_2_△t |≥ V _i_x_△t_limit_1 ; | V _ij_x_2_△t -V _ij_x_1_△t |≥ V _i_x_△t_limit_2 ; In the above formula, V _i_x_△t_limit_1 V is the warning threshold for the absolute value of the moving speed of any target origin of the i-th tower along the horizontal axis; _i_x_△t_limit_2 A warning threshold is set for the absolute value of the difference in moving speed between any two adjacent symmetrical target origins on the i-th tower section along the horizontal axis.

[0037] The method for monitoring the deflection angle of the longitudinal axis at the tower joint in step (8) is as follows: the central processing unit performs data comparison. When any of the following conditions exists, it indicates that the change in the longitudinal axis angle at the tower joint taken by the jth high-definition camera on the bottom platform of the i-th tower section is abnormal, and a safety warning of abnormal change in the angle at the i-th tower joint is issued: | A _ij_y_1 |≥ A _i_y_limit_1 ; | A _ij_y_2 |≥ A _i_y_limit_1 ; | A _ij_y_2 - A _ij_y_1 |≥ A _i_y_limit_2 ; In the above formula, A _ij_y_1 and A _ij_y_2 A is the deflection angle of the longitudinal axes of the two targets relative to their respective longitudinal axes in the quasi-static reference position when the wind turbine is in working state, photographed by the jth high-definition camera on the bottom platform of any i-th tower section; _i_x_limit_1 A is the warning threshold for the absolute value of the deflection angle of the longitudinal axis of any target in the i-th tower relative to the longitudinal axis in the quasi-static position; _i_y_limit_2 A warning threshold is set for the absolute value of the difference in deflection angles of any two adjacent symmetrical target longitudinal axes of the i-th tower relative to their respective longitudinal axes in the quasi-static orientation.

[0038] The method for monitoring the deflection angular velocity of the longitudinal axis at the tower joint in step (8) is as follows: _ij_y_1 and A _ij_y_2 Based on the time interval △t between two adjacent frames of images, calculate A within △t time _ij_y_1 , A _ij_y_2 The change value; Divide the change value by the time interval △t to obtain the deflection angular velocity ω of the two target longitudinal axes relative to their respective longitudinal axes in the quasi-static orientation _ij_x_1_△t ,ω _ij_x_2_△t ; The central processor compares the data. When any of the following conditions exists, it indicates that the deflection angular velocity of the tower joint captured by the jth high-definition camera on the bottom platform of the i-th tower section is obviously abnormal, and a safety warning of abnormal deflection angular velocity of the corresponding tower joint gap is issued: |ω _ij_x_1_△t |≥ω _i_x_△t_limit_1 ; |ω _ij_x_2_△t |≥ω _i_x_△t_limit_1 ; |ω _ij_x_2_△t -ω _ij_x_1_△t |≥ω _i_x_△t_limit_2 ; In the above formula, ω _i_x_△t_limit_1 The warning threshold value is set for the absolute value of the deflection angular velocity of the longitudinal axis of any target in the i-th tower relative to the longitudinal axis in the quasi-static position; ω _i_x_△t_limit_2 A warning threshold is set for the absolute value of the difference in the deflection angular velocity of any two adjacent symmetrical target longitudinal axes of the i-th tower relative to their respective longitudinal axes in the quasi-static orientation.

Claims

1. A method for monitoring a concrete tower of a wind turbine generator system based on target image recognition, the target (1) comprising a lampshade (11), a group of wicks (12) inside the lampshade, and a power source, the lampshade (11) comprising a bottom plate (13), side plates (15) on the sides of the bottom plate, and a panel (14) on the top of the bottom plate, the panel being provided with a hollow light-transmitting area (16); the light-transmitting area (16) is a cross-shaped light-transmitting area, the longitudinal axis light-transmitting area length of the cross-shaped light-transmitting area is greater than the transverse axis light-transmitting area length, and a circular non-light-transmitting area (17) is provided at the center of the cross-shaped light-transmitting area; It is characterized in that The method comprises the following steps: (1) A group of targets (1) is arranged side by side in the middle or lower middle part of each vertical joint of each section of the concrete tower. Each group of targets consists of two targets. The two targets are symmetrically arranged on both sides of the joint of the concrete tower. The two targets are at the same height from the bottom platform of the tower section and at the same distance from the joint. (2) A high-definition camera (2) is arranged on the tower platform below each group of targets, near the center of the tower platform. A high-definition camera (2) is arranged below each group of targets. The lens of the high-definition camera is directed toward the group of targets and can capture all images of the group of targets. (3) Number the concrete tower, targets and high-definition cameras. The serial numbers of each concrete tower section from bottom to top are recorded as 1, 2, 3... i ....... n, where n indicates that there are n concrete tower sections in total; the j-th high-definition camera on the bottom platform of the i-th tower section is marked as the ij-th high-definition camera, 1≤j≤m, where m indicates that the total number of high-definition cameras on the bottom platform of this tower section is m; in each group of targets, the origin, horizontal axis and vertical axis of the left target are marked as O1, X1 and Y1 respectively, and the origin, horizontal axis and vertical axis of the right target are marked as O2, X2 and Y2 respectively; (4) When the wind turbine is in operation, the lamp core (12) in the target (1) is powered on and emits light; all high-definition cameras collect and shoot image data information of the target above their respective lenses in real time, and transmit the collected image data information to the central processor through the data acquisition and transmission module; (5) The central processor receives the image data information sent by the data acquisition and transmission module, processes and analyzes the received image data information, determines the position and direction of the target based on the grayscale index and shape characteristics of each area in the image; determines the position and angle direction information of the origin, horizontal axis and vertical axis of each target based on the grayscale index and state characteristics of the target's transparent area and non-transparent area; (6) The target orientation when the wind speed is low and the wind turbine has not started working is taken as the quasi-static reference orientation of the target; (7) When the wind turbine is in operation, obtain target image data information according to steps (4) and (5); (8) The central processing unit processes and analyzes the processed target image data information, monitors the deformation and movement speed of the horizontal axis at the tower joint, as well as the deflection angle and deflection angular velocity of the vertical axis, and issues corresponding safety warnings when the data is abnormal.

2. The wind turbine concrete tower monitoring method based on target image recognition according to claim 1 is characterized in that: An edge (18) of a non-light-transmitting area of ​​the inner surface of the panel (14) adjacent to the light-transmitting area is provided with an inclination angle of ≥30°.

3. The wind turbine concrete tower monitoring method based on target image recognition according to claim 1 is characterized in that: The bottom plate (13), the side plates (15) and the panel (14) outside the light-transmitting area are all made of non-light-transmitting materials.

4. The method for monitoring a wind turbine concrete tower based on target image recognition according to claim 1, characterized in that: The high-definition camera (2) adopts a high shooting frame rate and is equipped with a wide-angle lens (21); a base (23) is provided at the bottom of the high-definition camera, and the high-definition camera base is fixed to the tower platform by bonding or bolting; the angle between the body (22) of the high-definition camera and the base (23) is adjustable, thereby adjusting the pitch angle of the high-definition camera lens.

5. The wind turbine concrete tower monitoring method based on target image recognition according to claim 1 is characterized in that: The data acquisition and transmission module can receive the image data captured by each high-definition camera, and transmit the received image data to the central processing unit in a wired or wireless manner.

6. The wind turbine concrete tower monitoring method based on target image recognition according to claim 1 is characterized in that: The central processing unit receives the image data information sent by the data acquisition and transmission module. The image processing software in the central processing unit processes and analyzes the received image data, and identifies the position and direction of the target in the image based on the grayscale index and shape characteristics of each area in the image.

7. The wind turbine concrete tower monitoring method based on target image recognition according to claim 1 is characterized in that: The method for monitoring the horizontal axis deformation at the tower joint in step (8) is as follows: the central processing unit performs data comparison. When any of the following conditions exists, it indicates that the deformation at the tower joint taken by the jth high-definition camera on the bottom platform of the i-th tower section is obviously abnormal, and a safety warning of abnormal deformation at the i-th tower joint is issued: | D _ij_x_1 |≥ D _i_x_limit_1 ; | D _ij_x_2 |≥ D _i_x_limit_1 ; | D _ij_x_2 - D _ij_x_1 |≥ D _i_x_limit_2 ; In the above formula, D _ij_x_1 and D _ij_x_2 D is the displacement of the origins of the two targets along the horizontal axis relative to their respective origins in the quasi-static reference position when the wind turbine is in working state, photographed by the jth high-definition camera on the bottom platform of any i-th tower section; _i_x_limit_1 The threshold value for early warning of the absolute value of the displacement of the origin of any target of the i-th tower along the horizontal axis relative to the origin under the quasi-static reference orientation is set; D _i_x_limit_2 A warning threshold is set for the absolute value of the displacement difference of any two adjacent symmetrical target origins on the i-th tower section relative to their respective origins in the quasi-static reference orientation along the horizontal axis.

8. The method for monitoring a wind turbine concrete tower based on target image recognition according to claim 7 is characterized in that: The method for monitoring the moving speed at the tower joint in step (8) is as follows: _ij_x_1 , D _ij_x_2 Based on the time interval △t between two adjacent frames of images, calculate D within △t time _ij_x_1 , D _ij_x_2 The change value is divided by the time interval △t to obtain the moving speed V of the two target origins along the horizontal axis. _ij_x_1_△t and V _ij_x_2_△t The central processor compares the data. If any of the following conditions exists, it indicates that the moving speed of the joint captured by the jth high-definition camera on the bottom platform of the i-th tower section is obviously abnormal, and a safety warning of abnormal deformation speed of the corresponding tower joint gap is issued: | V _ij_x_1_△t |≥ V _i_x_△t_limit_1 ; | V _ij_x_2_△t |≥ V _i_x_△t_limit_1 ; | V _ij_x_2_△t - V _ij_x_1_△t |≥ V _i_x_△t_limit_2 ; In the above formula, V _i_x_△t_limit_1 V is the warning threshold for the absolute value of the moving speed of any target origin of the i-th tower along the horizontal axis; _i_x_△t_limit_2 A warning threshold is set for the absolute value of the difference in moving speed between any two adjacent symmetrical target origins on the i-th tower section along the horizontal axis.

9. The method for monitoring a wind turbine concrete tower based on target image recognition according to claim 1, characterized in that: The method for monitoring the deflection angle of the longitudinal axis at the tower joint in step (8) is as follows: the central processing unit performs data comparison. When any of the following conditions exists, it indicates that the change in the longitudinal axis angle at the tower joint taken by the jth high-definition camera on the bottom platform of the i-th tower section is abnormal, and a safety warning of abnormal change in the angle at the i-th tower joint is issued: | A _ij_y_1 |≥ A _i_y_limit_1 ; | A _ij_y_2 |≥ A _i_y_limit_1 ; | A _ij_y_2 - A _ij_y_1 |≥ A _i_y_limit_2 ; In the above formula, A _ij_y_1 and A _ij_y_2 A is the deflection angle of the longitudinal axes of the two targets relative to their respective longitudinal axes in the quasi-static reference position when the wind turbine is in working state, photographed by the jth high-definition camera on the bottom platform of any i-th tower section; _i_x_limit_1 A is the warning threshold for the absolute value of the deflection angle of the longitudinal axis of any target in the i-th tower relative to the longitudinal axis in the quasi-static position; _i_y_limit_2 A warning threshold is set for the absolute value of the difference in deflection angles of any two adjacent symmetrical target longitudinal axes of the i-th tower relative to their respective longitudinal axes in the quasi-static orientation.

10. The method for monitoring a wind turbine concrete tower based on target image recognition according to claim 9, characterized in that: The method for monitoring the deflection angular velocity of the longitudinal axis at the tower joint in step (8) is as follows: _ij_y_1 and A _ij_y_2 Based on the time interval △t between two adjacent frames of images, calculate A within △t time _ij_y_1 , A _ij_y_2 The change value; Divide the change value by the time interval △t to obtain the deflection angular velocity ω of the two target longitudinal axes relative to their respective longitudinal axes in the quasi-static orientation _ij_x_1_△t ,ω _ij_x_2_△t ; The central processor compares the data. When any of the following conditions exists, it indicates that the deflection angular velocity of the tower joint captured by the jth high-definition camera on the bottom platform of the i-th tower section is obviously abnormal, and a safety warning of abnormal deflection angular velocity of the corresponding tower joint gap is issued: | oh _ij_x_1_△t |≥ ω _i_x_△t_limit_1 ; | oh _ij_x_2_△t |≥ ω _i_x_△t_limit_1 ; | oh _ij_x_2_△t - oh _ij_x_1_△t |≥ ω _i_x_△t_limit_2 ; In the above formula, ω _i_x_△t_limit_1 The warning threshold value is set for the absolute value of the deflection angular velocity of the longitudinal axis of any target in the i-th tower relative to the longitudinal axis in the quasi-static position; ω _i_x_△t_limit_2 A warning threshold is set for the absolute value of the difference in the deflection angular velocity of any two adjacent symmetrical target longitudinal axes of the i-th tower relative to their respective longitudinal axes in the quasi-static orientation.

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