Method and device for detecting loosening of bolts of top cover of pumped storage unit

Abstract

The embodiment of the application provides a kind of pumped storage unit top cover bolt loosening detection method and device, comprising: when unit is operated, top cover bolt nut image is obtained;Wherein, nut is included in top cover bolt nut image, and marking line is provided on nut;Marking line on nut in the top cover bolt nut image is extracted;According to the pixel point on the marking line, the current position of the marking line is determined;According to the current position and the reference position under fastening state, the state of top cover bolt is determined.The method of the application can accurately detect the state of top cover bolt, and will not be affected by environmental factors, safe and reliable.

Description

Technical Field

[0001] This application relates to the field of pumped storage technology, and in particular to a method and apparatus for detecting loose bolts on the top cover of a pumped storage unit. Background Technology

[0002] During operation, the top cover of a pumped storage unit bears the loads generated by high water head and significant water pressure pulsations. Especially during the transition process, the top cover is subjected to the impact of water hammer pressure waves. If the top cover bolts loosen, they may break, causing the top cover to be lifted, potentially damaging the unit or even flooding the power plant. Manual inspections of the top cover bolts, conducted irregularly, cannot accurately determine their tightness, and entering the turbine room during unit operation poses safety risks. Using elastic washers to detect the tightness of the top cover bolts and nuts introduces additional safety risks, and the accuracy of these washers is easily affected by temperature changes. Summary of the Invention

[0003] In view of this, the purpose of this application is to provide a method and device for detecting loose top cover bolts of a pumped storage unit, which can accurately detect the condition of the top cover bolts.

[0004] To achieve the above objectives, embodiments of this application provide a method for detecting loose bolts on the top cover of a pumped storage unit, including:

[0005] During unit operation, images of top cover bolts and nuts are acquired; wherein, the top cover bolt and nut images include nuts, and the nuts are marked with lines;

[0006] Extract the marking lines on the nuts from the top cover bolt and nut image;

[0007] The current position of the marker line is determined based on the pixels on the marker line;

[0008] The state of the top cover bolts is determined based on the current position and the reference position under the tightened state.

[0009] Optionally, extract the marking lines on the nuts in the top cover bolt and nut image, including:

[0010] Determine the area of ​​the nut in the top cover bolt and nut image;

[0011] For each pixel in the region:

[0012] If the difference between the color value of the pixel and the color reference value of the marker line is less than a preset color difference threshold, and the distance from the pixel to the preset reference point is less than a preset distance threshold,

[0013] The pixel is the pixel on the marked line.

[0014] Optionally, determining the current position of the marker line based on the pixels on the marker line includes:

[0015] Linear fitting is performed on each pixel on the marker line to obtain the current slope of the marker line.

[0016] Optionally, the state of the top cover bolts is determined based on the current position and the reference position under the tightened state, including:

[0017] Calculate the loosening angle between the current slope and the reference slope under the tightened state;

[0018] If the loosening angle is greater than the preset loosening threshold, the top cover bolt is in a loose state.

[0019] Optionally, the top cover bolt and nut image includes multiple sets of top cover bolts and nuts; the loosening angle between the current slope and the reference slope in the tightened state is calculated according to formula (1):

[0020] θ i =atan(c i )-atan(a i (1)

[0021] Among them, c i Let a be the current slope of the marking line on the i-th nut. i Let θ be the reference slope of the marking line on the i-th nut. i Let be the loosening angle of the i-th top cover bolt.

[0022] Optionally, before acquiring the image of the top cover bolts and nuts while the unit is running, the following steps are also included:

[0023] When the unit is shut down, the top cover bolts and nuts are in a tightened state, and an image of the top cover bolts and nuts being tightened is acquired; the image of the top cover bolts and nuts being tightened includes the nuts in a tightened state, and the marking line on the nuts is the reference marking line;

[0024] Extract the reference mark line on the nut in the top cover bolt and nut fastening image;

[0025] The reference position is determined based on the pixels on the reference mark line.

[0026] Optionally, after obtaining the images of the top cover bolts and nuts tightened, the process also includes:

[0027] The color values ​​of a predetermined number of pixels on the reference marker line are extracted using a color picker;

[0028] The color reference value is determined based on the color values ​​of the predetermined number of pixels.

[0029] Optionally, the top cover bolt and nut tightening image further includes the top cover bolt, and the reference point is the center pixel of the top cover bolt; after obtaining the top cover bolt and nut tightening image, it further includes:

[0030] Determine the pixel on the reference mark line that is farthest from the center pixel;

[0031] The distance threshold is determined based on the distance from the pixel to the center pixel.

[0032] Optionally, after extracting the reference mark line on the nut in the top cover bolt and nut tightening image, the method further includes:

[0033] Add corresponding identification information to each nut and its corresponding top cover bolt in the top cover bolt and nut tightening image;

[0034] When it is determined that the top cover bolts are in a loose state, the following is also included:

[0035] Output alarm information; the alarm information includes the identification information of the loose top cover bolts and the corresponding loosening angle.

[0036] This application embodiment also provides a detection device for loose bolts on the top cover of a pumped storage unit, including:

[0037] The acquisition module is used to acquire images of top cover bolts and nuts during unit operation; wherein, the top cover bolt and nut images include nuts, and the nuts are marked with marking lines;

[0038] The extraction module is used to extract the marking lines on the nuts in the top cover bolt and nut image;

[0039] A position determination module is used to determine the current position of the marker line based on the pixels on the marker line;

[0040] The detection module is used to determine the state of the top cover bolts based on the current position and the reference position under the tightened state.

[0041] As can be seen from the above description, the method and apparatus for detecting loose top cover bolts of pumped storage units provided in this application acquires an image of the top cover bolt and nut during unit operation, and extracts the marking line on the nut from the top cover bolt and nut image. Based on the pixels on the marking line, the current position of the marking line is determined, and based on the current position of the marking line and the reference position under the tightened state, the state of the top cover bolt is determined. The method of this application can accurately detect the state of the top cover bolts, is not affected by environmental factors, and is safe and reliable. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 This is a schematic diagram of the method flow of an embodiment of this application;

[0044] Figure 2 This is a schematic diagram showing the deployment of the image acquisition unit according to an embodiment of this application;

[0045] Figure 3 This is a top view of the top cover bolts and nuts according to an embodiment of this application;

[0046] Figure 4 This is a top view of the top cover bolt and nut according to another embodiment of this application;

[0047] Figure 5 This is a schematic diagram of the top cover bolt and nut image according to an embodiment of this application;

[0048] Figure 6 This is a block diagram of the device structure according to an embodiment of this application;

[0049] Figure 7 This is a block diagram of the electronic device structure according to an embodiment of this application. Detailed Implementation

[0050] To make the objectives, technical solutions, and advantages of this disclosure clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0051] It should be noted that, unless otherwise defined, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by one of ordinary skill in the art to which this disclosure pertains. The terms "first," "second," and similar terms used in the embodiments of this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are only used to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0052] As described in the background section, to ensure the safe and stable operation of pumped storage units, it is necessary to ensure that the top cover bolts and nuts are in a tight state. Considering the special operating environment of the unit, the inspection of the top cover bolts must ensure safety, be unaffected by environmental factors, and guarantee the accuracy of the inspection results.

[0053] In view of this, this application provides a method for detecting loose top cover bolts of a pumped storage unit. A marking line is set on the nut. During unit operation, an image acquisition unit periodically acquires images of the top cover bolt and nut, extracts the marking line from the image, and determines whether the top cover bolt is loose based on the deviation of the current position of the marking line from its reference position under tight conditions. Utilizing image processing technology to detect the condition of the top cover bolts provides high detection accuracy, is unaffected by environmental factors, and has reliable performance.

[0054] The technical solution of this application will be further described in detail below through specific embodiments.

[0055] like Figure 1-3 As shown in Figure 5, this application provides a method for detecting loose bolts on the top cover of a pumped storage unit, including:

[0056] S101: During unit operation, acquire images of top cover bolts and nuts; wherein, the top cover bolt and nut images include nuts with marking lines on them;

[0057] In this embodiment, the top cover of the pumped storage unit is deployed in the water turbine chamber. The top cover and the seat ring are connected by several sets of top cover bolts 20 and nuts 10. The top cover has several first bolt holes on its circumference, and the seat ring has several second bolt holes on its circumference. The second bolt holes have threads that match the top cover bolts. The top cover bolts 20 pass through the corresponding first bolt holes and are fastened to the seat ring through the second bolt holes. The top cover and the seat ring are then closed together by the nuts 10 and the top cover bolts 20. To ensure the stability of the unit's operation, the top cover bolts 20 and nuts 10 need to be kept in a tight state.

[0058] like Figure 2 As shown, images of the top cover bolts and nuts are acquired using image acquisition units. To acquire images of all the top cover bolts and nuts, multiple image acquisition units (e.g., cameras) are arranged at equal angles along the circumference above the unit. In some methods, since a typical top cover has 70-80 sets of top cover bolts and nuts, an image acquisition unit can be arranged at 45-degree intervals on the wall of the water turbine chamber pit. Each image acquisition unit can acquire images of approximately 10 sets of top cover bolts and nuts within its image acquisition range.

[0059] In some embodiments, a marking line 30 is provided on the top surface of the nut 10 to detect whether the position of the nut has changed. For easy and accurate identification, the color of the marking line 30 is clearly different from the colors of the top cap bolt 20, the nut 10, and the top cap, and the marking line 30 has a certain width. Optionally, a red marking line can be applied at a predetermined position on the top surface of the nut. The width of the marking line is 1-2 cm. The position of the marking line on each nut can be different or approximately the same; considering aesthetic requirements, the position of the marking line on each nut should be kept as consistent as possible.

[0060] S102: Extract the marking lines on the nuts in the top cover bolt and nut image;

[0061] In this embodiment, during unit operation, images of the top cover bolts and nuts are periodically acquired using an image acquisition unit, for example, every few minutes. For the acquired images, image processing identifies each nut, and for each nut, the marking lines are extracted. Optionally, a contour extraction method can be used to identify the region of each nut from the top cover bolt and nut images, and further, the corresponding marking lines can be extracted from the region of each nut.

[0062] S103: Determine the current position of the marker line based on the pixels on the marker line;

[0063] In this embodiment, after extracting the marking line on the nut, the current position of the marking line is determined based on all the pixels on the marking line. For example, based on the coordinates of each pixel on the marking line, a linear fit is performed on each pixel on the marking line to obtain the current slope of the marking line.

[0064] S104: Determine the state of the top cover bolts based on the current position and the reference position under the tightened state.

[0065] In this embodiment, after determining the current position of the marking line, the current position of the marking line is compared with the predetermined reference position when the top cover bolt and nut are in a tightened state. Based on the degree of deviation of the current position from the reference position, it is determined whether the top cover bolt has become loose.

[0066] The method for detecting loose top cover bolts in pumped storage units provided in this embodiment involves acquiring images of the top cover bolts and nuts using multiple deployed image acquisition units during unit operation. Marking lines on the nuts are extracted from these images, and the current position of the marking lines is determined based on the pixels on these lines. This current position is then compared to a reference position under tight conditions to determine the overall condition of the top cover bolts. This image processing method accurately detects the condition of the top cover bolts, is unaffected by environmental factors, offers reliable performance, eliminates the need for on-site inspections by maintenance personnel, and ensures high safety.

[0067] In some implementations, the marking lines on the nuts in the top cover bolt and nut image are extracted, including:

[0068] Identify the area of ​​the nut in the top cover bolt and nut image;

[0069] For each pixel in the region:

[0070] If the difference between the color value of a pixel and the color reference value of the marker line is less than a preset color difference threshold, and the distance from the pixel to the preset reference point is less than a preset distance threshold, then the pixel is a pixel on the marker line.

[0071] In this embodiment, based on the acquired images of the top cover bolts and nuts, the region where each nut is located in the image is first extracted using a contour extraction method. For each region where a nut is located, the marking lines on the nut are further extracted based on the characteristics of the marking lines. Taking a nut as an example, for each pixel within the nut's region, the color value of the pixel is compared with the color reference value of the marking line. If the difference between the two is less than a color difference threshold, the distance between the pixel and the reference point is calculated. If the distance between the two points is less than a distance threshold, the pixel is determined to be a point on the marking line.

[0072] In some methods, comparing the color value of a pixel with the color reference value of a marker line means comparing the red component of the pixel's color value with the red reference value of the marker line, the green component of the pixel's color value with the green reference value of the marker line, and the blue component of the pixel's color value with the blue reference value of the marker line. If all three color components of the pixel are less than the corresponding color difference threshold, it is determined that the pixel's color is similar to or the same as the color of the marker line.

[0073] In some methods, the reference point is the center pixel of the top cover bolt corresponding to the top cover bolt nut image. During unit operation, it is assumed that the center pixel of the top cover bolt will not change. For each pixel within the region of each nut, the distance from that pixel to the center pixel o of the corresponding top cover bolt is calculated. If the distance between the two points is less than a distance threshold, and the pixel's color is similar to or the same as the marking line, it can be determined that the pixel is a point on the marking line on that nut, thus accurately identifying the marking line on each nut.

[0074] Optionally, to extract the marking line on the nut in the top cover bolt and nut image, after acquiring the top cover bolt and nut image, for each pixel in the image, the color value of the pixel is compared with the color reference value of the marking line. If the difference between the two is less than the color difference threshold, the distance between the pixel and the reference point is calculated. If the distance between the two points is less than the distance threshold, the pixel is determined to be a point on the marking line, and the top cover bolt corresponding to the reference point corresponds to the nut where the marking line is located.

[0075] In some embodiments, the state of the top cover bolts is determined based on the current position of the marking line and a reference position in the tightened state, including:

[0076] Calculate the loosening angle between the current slope and the reference slope under the tightened state;

[0077] If the loosening angle is greater than the preset loosening threshold, the top cover bolts are in a loose state.

[0078] Combination Figure 4 As shown, in this embodiment, after extracting all pixels on the marker line, the coordinates of each pixel are linearly fitted to obtain the line l1 containing the marker line and the current slope c of line l1. i Based on the current slope and the reference slope a of the straight line l2 containing the reference mark line corresponding to the top cover bolt in the tightened state. i Calculate the rotation angle of line l1 relative to line l2, and use this rotation angle as the loosening angle of the top cover bolt. If the loosening angle is greater than the loosening threshold, it is determined that the top cover bolt has loosened.

[0079] In some methods, the top cover bolt and nut image includes multiple sets of top cover bolts and nuts; the formula for calculating the loosening angle between the current slope and the reference slope in the tightened state is:

[0080] θ i =atan(c i )-atan(a i (1)

[0081] Among them, c i Let a be the current slope of the marking line on the i-th nut. i Let θ be the reference slope of the marking line for the i-th nut in the tightened state. i Let be the loosening angle of the i-th top cover bolt.

[0082] In some embodiments, when it is determined that the top cover bolt is in a loose state based on the current position and the reference position under the tightened state, the method further includes: outputting alarm information, which includes an identifier of the loose top cover bolt. That is, after identifying each group of top cover bolts and nuts included in the top cover bolt and nut image through image processing methods, the state of each top cover bolt is detected separately. When one or more top cover bolts are detected to be loose, alarm information is output in a timely manner, indicating the identifier of the loose top cover bolt in the alarm information, so that maintenance personnel can quickly identify the loose top cover bolt and eliminate potential hazards as soon as possible. Optionally, after processing the top cover bolt and nut image and identifying multiple nuts and marking lines on each nut, identification information can be added to each nut and its corresponding bolt. For example, they can be numbered according to the top cover bolt serial number marked by the power station. When a loose top cover bolt is detected in the image, the bolt number and loosening angle are output.

[0083] In some embodiments, before acquiring the image of the top cover bolts and nuts while the unit is in operation, the process further includes:

[0084] When the unit is shut down, the top cover bolts and nuts are in a tightened state, and an image of the top cover bolts and nuts being tightened is acquired; the image of the top cover bolts and nuts being tightened includes the nuts in a tightened state, and the marking line on the nuts is the reference marking line;

[0085] Extract the baseline marking line on the nut from the top cover bolt and nut fastening image;

[0086] Determine the reference position based on the pixels on the reference mark line.

[0087] In this embodiment, before real-time detection, with the unit shut down, the top cover bolts 20 and nuts 10 are tightened to meet the preload requirements. An image acquisition unit then captures an image of the top cover bolt and nut tightening in this state. By processing this image, the reference position of the reference mark line on the nut in the tightened state is determined. Specifically, based on the top cover bolt and nut tightening image, the region where the nut is in the tightened state is extracted. For each pixel in the region, the pixel's color value is compared with the reference color value of the reference mark line. If the pixel's color is similar to or the same as the reference mark line's color, the distance from the pixel to the center pixel of the corresponding top cover bolt is calculated. If the distance between the two points is less than a distance threshold, then the pixel is a point on the reference mark line. After processing all pixels in the region, all pixels on the reference mark line are obtained. Linear fitting is then performed on the coordinates of all pixels on the reference mark line to obtain the straight line l2 where the reference mark line is located: Y = a i X+b i and the reference slope a of line l2 i .

[0088] In some embodiments, to determine the color reference value of the reference mark line, after acquiring the image of the top cover bolt and nut tightening, the following steps are also included:

[0089] Use a color picker to extract the color values ​​of a predetermined number of pixels on the baseline marker line;

[0090] The color reference value is determined based on the color values ​​of a predetermined number of pixels.

[0091] Combination Figure 3 As shown, after acquiring the image of the top cover bolts and nuts tightened, a color picker is used to collect the color values ​​of a certain number of pixels on the baseline marker line. Then, based on the color values ​​of each pixel, the red, green, and blue baseline values ​​are calculated. For example, extracting the color values ​​of the two endpoints and any two points in the middle of the baseline marker line, using the average of the red components of the four pixels as the red baseline value, the average of the green components of the four pixels as the green baseline value, and the average of the blue components of the four pixels as the blue baseline value, can be expressed as:

[0092]

[0093] Among them, R LM1 G LM1 B LM1 These are the red, green, and blue components of the color value of the first pixel, respectively. LM2 G LM2 B LM2 These are the red, green, and blue components of the color value of the second pixel, respectively. LM3 G LM3 B LM3 These are the red, green, and blue components of the color value of the third pixel, respectively. LM4 G LM4 B LM4 These are the red, green, and blue components of the fourth pixel's color value. The above method for selecting pixels and calculating color reference values ​​is merely an illustrative example. To improve the accuracy of the color reference values, more pixel values ​​can be extracted from different positions on the reference mark line, and the color reference values ​​can be calculated accordingly. There are no specific limitations on the number of pixels, the selection method, or the method for calculating the color reference values.

[0094] In some embodiments, after acquiring the image of the top cover bolts and nuts tightened, in order to determine the distance threshold, the method further includes:

[0095] Determine the pixel on the reference mark line that is furthest from the center pixel of the corresponding top cover bolt;

[0096] The distance threshold is determined based on the distance from the pixel to the center pixel.

[0097] In this embodiment, after acquiring the image of the top cover bolt and nut fastening, the region where the top cover bolt is located is extracted from the image based on the characteristics of the top cover bolt. The center pixel of the top cover bolt is extracted from the region where the top cover bolt is located. For the two pixels at the very end (e.g., the leftmost and rightmost ends) of the reference mark line on the nut corresponding to the top cover bolt, the distance from the two pixels to the center pixel of the top cover bolt is calculated respectively. The pixel farthest from the center pixel is selected, and the distance threshold is determined based on the distance from the center pixel.

[0098] In some methods, the formula for calculating the distance threshold is:

[0099]

[0100] Where, d i Let k be the threshold distance between the top cover bolt and nut in the i-th group, where k is a set coefficient, for example, 1.2; (X LSi Y LSi Let (X) be the coordinates of the center pixel of the i-th top cover bolt. LMi Y LMi ) represents the coordinates of the pixel furthest from the center pixel on the reference mark line of the i-th nut.

[0101] This application provides a method for detecting loose top cover bolts in a pumped storage unit. During unit operation, an image acquisition unit periodically captures images of the top cover bolts and nuts. These images are processed to extract marking lines on the nuts. The current position of the marking lines is compared with a reference position under tightened conditions. If the current position deviates from the reference position to a certain extent, it is determined that the top cover bolts are loose. This method is applicable to the operating environment of pumped storage units, eliminates the need for manual inspection, ensures safety, is less affected by environmental factors, and guarantees the accuracy and reliability of the detection results.

[0102] It should be noted that the method in this embodiment can be executed by a single device, such as a computer or server. The method can also be applied in a distributed scenario, where multiple devices cooperate to complete the task. In such a distributed scenario, one of these devices may execute only one or more steps of the method in this embodiment, and the multiple devices will interact with each other to complete the method described.

[0103] It should be noted that the above description describes specific embodiments of this specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims may be performed in a different order than that shown in the embodiments and still achieve the desired results. Furthermore, the processes depicted in the drawings do not necessarily require the specific or sequential order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0104] like Figure 6 As shown in the embodiment of this application, a detection device for loose bolts on the top cover of a pumped storage unit is also provided, comprising:

[0105] The acquisition module is used to acquire images of the top cover bolts and nuts during unit operation; the images of the top cover bolts and nuts include the nuts, which have marking lines.

[0106] The extraction module is used to extract the marking lines on the nuts in the top cover bolt and nut image;

[0107] The position determination module is used to determine the current position of the marker line based on the pixels on the marker line;

[0108] The detection module is used to determine the state of the top cover bolts based on the current position and the reference position under the tightened state.

[0109] For ease of description, the above devices are described in terms of function, divided into various modules. Of course, in implementing the embodiments of this application, the functions of each module can be implemented in one or more software and / or hardware.

[0110] The apparatus described above is used to implement the corresponding methods in the foregoing embodiments and has the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0111] Figure 7 This embodiment illustrates a more specific hardware structure of an electronic device, which may include a processor 1010, a memory 1020, an input / output interface 1030, a communication interface 1040, and a bus 1050. The processor 1010, memory 1020, input / output interface 1030, and communication interface 1040 are interconnected internally via the bus 1050.

[0112] The processor 1010 can be implemented using a general-purpose CPU (Central Processing Unit), microprocessor, application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided in the embodiments of this specification.

[0113] The memory 1020 can be implemented in the form of ROM (Read Only Memory), RAM (Random Access Memory), static storage device, dynamic storage device, etc. The memory 1020 can store the operating system and other applications. When the technical solutions provided in the embodiments of this specification are implemented by software or firmware, the relevant program code is stored in the memory 1020 and is called and executed by the processor 1010.

[0114] The input / output interface 1030 is used to connect input / output modules to realize information input and output. Input / output modules can be configured as components within the device (not shown in the figure) or externally connected to the device to provide corresponding functions. Input devices may include keyboards, mice, touchscreens, microphones, various sensors, etc., while output devices may include displays, speakers, vibrators, indicator lights, etc.

[0115] The communication interface 1040 is used to connect a communication module (not shown in the figure) to enable communication between this device and other devices. The communication module can communicate via wired means (such as USB, Ethernet cable, etc.) or wireless means (such as mobile network, WIFI, Bluetooth, etc.).

[0116] Bus 1050 includes a pathway for transmitting information between various components of the device, such as processor 1010, memory 1020, input / output interface 1030, and communication interface 1040.

[0117] It should be noted that although the above-described device only shows the processor 1010, memory 1020, input / output interface 1030, communication interface 1040, and bus 1050, in specific implementations, the device may also include other components necessary for normal operation. Furthermore, those skilled in the art will understand that the above-described device may only include the components necessary for implementing the embodiments of this specification, and not necessarily all the components shown in the figures.

[0118] The electronic devices described above are used to implement the corresponding methods in the foregoing embodiments and have the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0119] The computer-readable medium of this embodiment includes permanent and non-permanent, removable and non-removable media, and information storage can be implemented by any method or technology. Information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic magnetic disk storage or other magnetic storage devices, or any other non-transfer medium that can be used to store information accessible by a computing device.

[0120] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of this disclosure (including the claims) is limited to these examples; within the framework of this disclosure, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of the embodiments of this application as described above, which are not provided in the details for the sake of brevity.

[0121] Additionally, to simplify the description and discussion, and to avoid obscuring the embodiments of this application, the well-known power / ground connections to integrated circuit (IC) chips and other components may or may not be shown in the provided drawings. Furthermore, the apparatus may be shown in block diagram form to avoid obscuring the embodiments of this application, and this also takes into account the fact that the details of the implementation of these block diagram apparatuses are highly dependent on the platform on which the embodiments of this application will be implemented (i.e., these details should be fully understood by those skilled in the art). While specific details (e.g., circuits) have been set forth to describe exemplary embodiments of this disclosure, it will be apparent to those skilled in the art that the embodiments of this application can be implemented without these specific details or with variations thereof. Therefore, these descriptions should be considered illustrative rather than restrictive.

[0122] Although this disclosure has been described in conjunction with specific embodiments thereof, many substitutions, modifications, and variations of these embodiments will be apparent to those skilled in the art from the foregoing description. For example, other memory architectures (e.g., dynamic RAM (DRAM)) may be used with the embodiments discussed.

[0123] The embodiments of this application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the embodiments of this application should be included within the protection scope of this disclosure.

Claims

1. A method for detecting loose bolts on the top cover of a pumped storage unit, characterized in that, An image acquisition unit is set up at predetermined angles on the wall of the waterwheel chamber pit. The method includes: During unit operation, images of top cover bolts and nuts are acquired using each image acquisition unit; wherein, the top cover bolt and nut images include nuts and top cover bolts, and the nuts are marked with lines; Extracting the marking line on the nut in the top cover bolt and nut image includes: using a contour extraction method to determine the region of the nut in the top cover bolt and nut image; for each pixel in the region: if the difference between the color value of the pixel and the color reference value of the marking line is less than a preset color difference threshold, and the distance from the pixel to a preset reference point is less than a preset distance threshold, the pixel is a pixel on the marking line; wherein, the reference point is the center pixel of the corresponding top cover bolt in the top cover bolt and nut image; The current position of the marker line is determined based on the pixels on the marker line; The state of the top cover bolts is determined based on the current position and the reference position under the tightened state.

2. The method according to claim 1, characterized in that, Determining the current position of the marker line based on the pixels on the marker line includes: Linear fitting is performed on each pixel on the marker line to obtain the current slope of the marker line.

3. The method according to claim 2, characterized in that, Based on the current position and the reference position under the tightened state, the state of the top cover bolts is determined, including: Calculate the loosening angle between the current slope and the reference slope under the tightened state; If the loosening angle is greater than the preset loosening threshold, the top cover bolt is in a loose state.

4. The method according to claim 3, characterized in that, The top cover bolt and nut image includes multiple sets of top cover bolts and nuts; the loosening angle between the current slope and the reference slope in the tightened state is calculated according to formula (1): θ i =attan(c i )-watch(a i ) (1) Among them, c i Let a be the current slope of the marking line on the i-th nut. i Let θ be the reference slope for the i-th nut. i Let be the loosening angle of the i-th top cover bolt.

5. The method according to claim 1, characterized in that, Before acquiring images of the top cover bolts and nuts while the unit is in operation, the following steps are also included: When the unit is shut down, the top cover bolts and nuts are in a tightened state, and an image of the top cover bolts and nuts being tightened is acquired; the image of the top cover bolts and nuts being tightened includes the nuts in a tightened state, and the marking line on the nuts is the reference marking line; Extract the reference mark lines from the top cover bolt and nut tightening image; The reference position is determined based on the pixels on the reference mark line.

6. The method according to claim 5, characterized in that, After obtaining the images of the top cover bolts and nuts tightened, the following steps are also included: The color values ​​of a predetermined number of pixels on the reference marker line are extracted using a color picker; The color reference value is determined based on the color values ​​of the predetermined number of pixels.

7. The method according to claim 5, characterized in that, After obtaining the images of the top cover bolts and nuts tightened, the following steps are also included: Determine the pixel on the reference mark line that is farthest from the center pixel; The distance threshold is determined based on the distance from the pixel to the center pixel.

8. The method according to claim 5, characterized in that, After extracting the reference mark line from the top cover bolt and nut tightening image, the method further includes: Add corresponding identification information to each nut and its corresponding top cover bolt in the top cover bolt and nut tightening image; When it is determined that the top cover bolts are in a loose state, the following is also included: Output alarm information; the alarm information includes the identification information of the loose top cover bolts and the corresponding loosening angle.

9. A detection device for loose bolts on the top cover of a pumped storage unit, characterized in that, An image acquisition unit is installed at predetermined angles on the wall of the waterwheel chamber pit. The device includes: The acquisition module is used to acquire images of the top cover bolts and nuts using each image acquisition unit during unit operation; wherein, the top cover bolt and nut images include nuts and top cover bolts, and the nuts are marked with marking lines; An extraction module is used to extract the marking line on the nut in the top cover bolt and nut image, including: determining the region of the nut in the top cover bolt and nut image using a contour extraction method; for each pixel in the region: if the difference between the color value of the pixel and the color reference value of the marking line is less than a preset color difference threshold, and the distance from the pixel to a preset reference point is less than a preset distance threshold, the pixel is a pixel on the marking line; wherein, the reference point is the center pixel of the corresponding top cover bolt in the top cover bolt and nut image; A position determination module is used to determine the current position of the marker line based on the pixels on the marker line; The detection module is used to determine the state of the top cover bolts based on the current position and the reference position under the tightened state.

Images