Water turbine rotating speed measuring method, system and equipment based on image algorithm and medium

Abstract

The invention relates to the technical field of water turbine rotating speed detection, and discloses a water turbine rotating speed measuring method, system and equipment based on an image algorithm and a medium. The method comprises the following steps: uniformly arranging a circle of color codes on the same-diameter circumference of the water turbine large shaft; collecting color code images through an image collector to obtain an image sequence; outputting the image sequence to an image processor for slicing processing, and reading the pixel height of a color code at a slice; calculating the rotating speed of the water turbine large shaft according to the pixel height change to obtain a rotating speed signal; the rotating speed signal is output to a monitoring system and a speed regulator; the monitoring system and the speed regulator participate in control execution according to the rotating speed signal to adjust the rotating speed of the unit. According to the invention, non-contact, high-precision and anti-electromagnetic interference measurement of the rotating speed of the water turbine is realized, the problems of high processing precision requirement, complex installation, high cost and difficult maintenance of the traditional fluted disc speed measurement are solved, and the measurement reliability and economical efficiency are improved.

Description

Technical Field

[0001] This invention relates to the field of turbine speed detection technology, specifically to a turbine speed measurement method, system, equipment, and medium based on image algorithms. Background Technology

[0002] In the field of turbine speed measurement technology, accurate and reliable speed monitoring is of great engineering significance for the safe and stable operation, efficiency optimization and automatic control of hydropower units. It directly affects the regulation performance and energy utilization efficiency of hydropower stations. Especially under low speed conditions during start-up and shutdown, the measurement accuracy and reliability are directly related to the start-up characteristics and protection logic of the unit.

[0003] Currently, the two widely used methods for frequency measurement—toothed disc frequency measurement and PT residual pressure frequency measurement—each have significant limitations. The toothed disc frequency measurement method requires mounting a precision metal toothed disc on the turbine shaft and arranging sensors around it for detection, calculating the rotational speed based on the sensor signals. Residual pressure frequency measurement, on the other hand, relies on electrical signals measured by voltage transformers for calculation. Both methods suffer from the following problems: high precision is required for the toothed disc machining, which is difficult and insufficient precision directly affects the measurement results; the installation process is complex, requiring the toothed disc to be strictly horizontal and all teeth to be on the same circular surface, and installation deviations can lead to measurement errors; the sensors are susceptible to interference in strong electromagnetic fields; and the overall manufacturing cost is high, making subsequent maintenance difficult.

[0004] Therefore, the key technical problem to be solved in this patent is how to overcome the processing and installation difficulties of traditional gear speed measurement through non-contact and highly stable measurement methods under low speed conditions during start-up and shutdown, and effectively resist electromagnetic interference to achieve real-time and accurate perception of turbine speed. Summary of the Invention

[0005] In view of the aforementioned existing problems, the present invention provides a method, system, device and medium for measuring the rotational speed of a water turbine based on an image algorithm.

[0006] Therefore, the technical problem solved by this invention is: how to overcome the stringent requirements of traditional gear disc speed measurement on machining and installation accuracy and its susceptibility to electromagnetic interference under low-speed conditions such as start-up and shutdown, through a non-contact, highly robust measurement method, while avoiding the signal attenuation and instability problems of residual pressure frequency measurement under low-speed and dynamic conditions, so as to achieve real-time, continuous and accurate sensing of turbine speed and ensure the balance between measurement response speed and accuracy when the speed changes dynamically.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a method for measuring the rotational speed of a water turbine based on an image algorithm, comprising, A ring of color marks is evenly arranged on the same diameter circumference of the turbine shaft; Color mark images are acquired using an image acquisition device to obtain an image sequence; The image sequence is output to the image processor for slicing, and the pixel height of the color mark at the slice is read. The rotational speed of the turbine shaft is calculated based on the pixel height of the color mark at the slice location, and the rotational speed signal is obtained. The speed signal is output to the monitoring system and the speed controller; Based on the received speed signal, the monitoring system and speed governor participate in the control execution to adjust the unit speed.

[0008] As a preferred embodiment of the image algorithm-based method for measuring the rotational speed of a water turbine according to the present invention, wherein: the step of uniformly arranging a ring of color marks on the same diameter circumference of the water turbine shaft includes, The color swatch is a complete graphic with different heights on the left and right sides. Its color is clearly distinguishable from the background color, and its height changes linearly. The number of color marks is N, and the color marks are ensured to be evenly distributed around the major axis on the same horizontal plane.

[0009] As a preferred embodiment of the image algorithm-based method for measuring the rotational speed of a water turbine according to the present invention, the step of acquiring color mark images through an image acquisition device to obtain an image sequence includes, The image acquisition device acquires images containing color marks at a fixed period T. The image acquisition device is aligned with the color mark area to ensure that the distance traveled by the image recognition area does not exceed the length of a complete color mark when the turbine rotates at its rated speed within the acquisition period. The acquired image data is transmitted to the image processor in real time to obtain a continuous image sequence.

[0010] As a preferred embodiment of the image algorithm-based turbine speed measurement method of the present invention, the step of outputting the image sequence to an image processor for slicing and reading the pixel height of the color mark at the slice includes: The image processor slices the acquired image sequence, sets image slices at predefined locations, performs vertical cutting, and reads the pixel height h of the color mark at the slice location.

[0011] As a preferred embodiment of the image algorithm-based turbine rotational speed measurement method of the present invention, the step of calculating the rotational speed of the turbine shaft based on the pixel height of the color mark at the slice and obtaining the rotational speed signal includes, Based on the change in pixel height during the continuous acquisition period, the turbine speed n is calculated using the speed calculation formula, with the unit being r / min, to obtain the speed signal. The calculation formula is as follows: in, N For the number of color marks,H The height of the rightmost pixel of the color mark. T The image acquisition period is expressed in seconds. The pixel height of the image slice is acquired during the (n+1)th measurement cycle. The pixel height of the image slice is acquired for the nth measurement cycle.

[0012] As a preferred embodiment of the image algorithm-based turbine speed measurement method of the present invention, wherein: the step of outputting the speed signal to the monitoring system and the speed governor includes, The monitoring system consists of five parts: sensors and actuators, data acquisition units, monitoring host, display and alarm devices, and communication network. The speed governor is the actuator of the monitoring system, which automatically adjusts the unit speed, distributes the load, prevents overspeed accidents, and ensures the stable operation of the power system.

[0013] As a preferred embodiment of the image algorithm-based turbine speed measurement method of the present invention, the step of adjusting the unit speed by means of a monitoring system and a speed governor participating in control execution based on the received speed signal includes: The various parts of the monitoring system work together to collect, process, control, alarm notification, and visualize data, while recording and displaying speed data, and performing fault diagnosis and performance analysis. The governor controls and adjusts the turbine unit speed in real time based on the diagnosis and analysis of the monitoring system.

[0014] This invention measures the turbine speed using image algorithms and outputs the speed signal to the monitoring system and governor, enabling real-time monitoring, diagnosis, and adjustment of the unit speed, thereby achieving stable operation of the power system, prevention of overspeed accidents, and performance optimization.

[0015] This invention provides a turbine speed measurement system based on image algorithms, comprising: The color mark arrangement module is responsible for evenly arranging a circle of color marks on the same diameter circumference of the turbine shaft. The color marks are designed with bright colors and obvious contrast with the background environment, and the height changes linearly to ensure that the pixel height changes are clearly captured during image recognition. The image acquisition module acquires images containing color marks at a fixed period T using an image acquisition device, generating a continuous image sequence. The image acquisition device is aligned with the color mark area to ensure that, at the rated speed of the turbine, the distance traversed by the image recognition area within the acquisition period does not exceed the length of a complete color mark. The image processing module receives the image sequence, performs slicing processing, sets the image slice part at a predefined position, performs vertical cutting, and reads the pixel height h of the color mark at the slice. At the same time, based on the change of pixel height in the continuous acquisition period, it uses the rotational speed calculation formula to calculate the turbine speed n and generates the rotational speed signal. The signal output module outputs the speed signal generated by the image processing module to the monitoring system and speed controller, serving as a communication interface to ensure the transmission of the speed signal and real-time control. The monitoring system module consists of five parts: sensors and actuators, data acquisition unit, monitoring host, display and alarm device, and communication network. After receiving the speed signal, it performs data acquisition, processing, control, alarm notification and visualization, while recording and displaying speed data, and performing fault diagnosis and performance analysis. The speed controller module, as the actuator of the monitoring system, automatically adjusts the unit speed, distributes the load, prevents overspeed accidents, and ensures the stable operation of the power system based on the received speed signal.

[0016] The present invention provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of a method for measuring the rotational speed of a water turbine based on an image algorithm.

[0017] The present invention provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of a method for measuring the rotational speed of a water turbine based on an image algorithm.

[0018] Compared with existing technologies, the advantages of this invention are as follows: This invention sets up a specific arrangement of color marks on the surface of the turbine shaft, uses an image acquisition device to acquire images of the color marks at fixed intervals, and uses an image processor to perform slice analysis on the images. By calculating the change in the pixel height of the color marks within adjacent cycles, the turbine speed is accurately calculated based on the speed formula. Finally, the speed signal is transmitted to the governor and monitoring system for real-time control. This method achieves full-process integration from color mark arrangement, image acquisition, data processing to speed feedback, effectively overcoming the shortcomings of traditional gear disc speed measurement methods, such as high requirements for machining accuracy and installation technology, susceptibility to electromagnetic interference, high cost, and complex maintenance. This invention adopts non-contact measurement, has a simple structure, is easy to install, requires no special sensors, avoids electromagnetic interference problems, and reduces machining and maintenance costs, improving the reliability and economy of turbine speed measurement, and is especially suitable for low-speed speed monitoring during start-up and shutdown. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 The present invention provides a system flowchart of a method for measuring the rotational speed of a water turbine based on an image algorithm, which is an embodiment of the present invention.

[0021] Figure 2 This is a system structure diagram of a water turbine speed measurement method based on an image algorithm, provided as an embodiment of the present invention.

[0022] Figure 3 This is a color-coded detail of a method for measuring the rotational speed of a water turbine based on an image algorithm, provided as an embodiment of the present invention. Detailed Implementation

[0023] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0024] Example 1, referring to Figure 1 The first embodiment of the present invention provides a method for measuring the rotational speed of a water turbine based on an image algorithm, comprising: S1: A ring of color marks is evenly arranged on the same diameter circumference of the turbine shaft. The color mark images are acquired by an image acquisition device to obtain an image sequence.

[0025] S2: Output the image sequence to the image processor for slicing and read the pixel height of the color mark at the slice.

[0026] S3: Calculate the rotational speed of the turbine shaft based on the pixel height of the color mark at the slice location, and obtain the rotational speed signal.

[0027] S4: Output the speed signal to the monitoring system and speed controller. Based on the received speed signal, the monitoring system and speed controller participate in the control execution and adjust the unit speed.

[0028] It should be noted that traditional methods for measuring turbine speed suffer from insufficient accuracy, poor reliability, and low economic efficiency due to the high precision requirements of the gear disc machining, complex installation process, susceptibility of sensors to strong electromagnetic interference, high manufacturing costs, and difficult maintenance. Therefore, it is also crucial to develop a turbine speed measurement system and method based on image algorithms to address issues such as non-contact measurement, resistance to electromagnetic interference, simplified installation process, reduced manufacturing costs, and improved maintenance convenience.

[0029] Therefore, to address the aforementioned problems of susceptibility to strong electromagnetic interference, high manufacturing costs, and difficult maintenance, leading to insufficient measurement accuracy, poor reliability, and low economic efficiency, steps S1-S4 are implemented. This involves uniformly arranging a ring of color marks around the same diameter circumference of the turbine shaft and acquiring images of these color marks using an image acquisition device to obtain an image sequence. This avoids the use of traditional electromagnetic sensors and improves resistance to strong electromagnetic interference. The image sequence is then output to an image processor for slicing, and the pixel height of the color marks at each slice is read. Based on the changes in pixel height during continuous acquisition cycles, the turbine speed is calculated using a speed calculation formula, improving measurement accuracy and algorithm stability. Furthermore, the speed signal is output to the monitoring system and governor for control execution, adjusting the unit speed and improving system reliability and maintenance convenience, while reducing maintenance difficulty and manufacturing costs. Simultaneously, the entire image algorithm-based turbine speed measurement process achieves the comprehensive goals of accurate turbine speed measurement, stable control, and improved economic efficiency.

[0030] Example 2, refer to Figure 1 - Figure 3 As an embodiment of the present invention, based on the above embodiment, a method for measuring the speed of a water turbine based on an image algorithm is provided.

[0031] In this embodiment of the application, step S1 involves uniformly arranging a ring of color marks around the same diameter circumference of the turbine shaft, acquiring images of the color marks using an image acquisition device to obtain an image sequence, including the following steps A1-A2: A1: The color mark is a complete graphic with different heights on the left and right sides. Its color is clearly distinguishable from the background color, and its height changes linearly. The number of color marks is N, and the color marks are evenly distributed around the major axis on the same horizontal plane.

[0032] A2: The image acquisition device acquires images containing color marks at a fixed period T. The image acquisition device is aligned with the color mark area to ensure that the distance traveled by the image recognition area does not exceed the length of a complete color mark when the turbine rotates at its rated speed within the acquisition period.

[0033] Specifically, such as Figure 2 - Figure 3As shown, a continuous ring of color marks is evenly arranged along the direction of rotation on the same diameter circumference of the turbine shaft; the shape of the color mark is an isosceles triangle and the color is red, which is clearly distinguished from the light gray of the turbine shaft primer; the number of color marks is N, and they are on the same horizontal plane.

[0034] The image acquisition device acquires color mark images at a fixed period T. The image acquisition device acquires images in a fixed color mark area. During the acquisition period, the turbine rotates according to its rated speed. The distance traveled by the image recognition area does not exceed the length of a complete color mark, ensuring that the image slices do not skip a complete color mark.

[0035] In an alternative implementation, irregular jagged patterns can be used as color marks, and the color mark images can be acquired by an image acquisition device to obtain an image sequence.

[0036] Specifically, the color mark graphic is serrated, the color is dark gray, the number of color marks is N, and they are arranged on the same diameter circumference of the turbine shaft, and evenly distributed around the shaft on the same horizontal plane. The image acquisition unit acquires images containing color marks at a fixed period T. The image acquisition unit is aligned with the color mark area, and the mounting bracket allows for slight shaking.

[0037] In another alternative implementation, a circle can be used as a color mark, and the color mark image can be acquired by an image acquisition device to obtain an image sequence.

[0038] Specifically, the color mark graphic is circular, the color is light blue, the number of color marks is N, and they are evenly distributed around the major axis on the same horizontal plane; The image acquisition device acquires images at a variable period. The period value is randomly switched by manually setting several fixed values. Within the acquisition period, the image acquisition device does not define the range of the color mark area.

[0039] In this embodiment of the invention, step S2, which involves outputting the image sequence to an image processor for slicing and reading the pixel height of the color mark at the slice location, includes: The image processor slices the acquired image sequence, sets image slices at predefined locations, performs vertical cutting, and reads the pixel height h of the color mark at the slice location.

[0040] Specifically, such as Figure 3 As shown, within the recognition area of ​​the image acquisition device, the leftmost pixel height of the isosceles triangle is 0, and the rightmost pixel height is H. An image slice is set at a predefined position, and the color mark is vertically cut. The pixel height h of the color mark at the slice is read.

[0041] In one alternative implementation, the image sequence can also be output to an image processor for averaging across multiple locations, and the pixel height of the color mark at each location can be read.

[0042] Specifically, the image processor slices the acquired image sequence, sets image slices at multiple random locations, vertically cuts each slice, reads the pixel height of the color mark at each slice, and finally calculates the average of these pixel heights as the final pixel height h.

[0043] In another alternative implementation, the image sequence can be output to an image processor for diagonal slicing, and the pixel height of the color stops at the slices can be read.

[0044] Specifically, the image processor slices the acquired image sequence, sets image slices at predefined locations, performs oblique cuts, and reads the pixel height h of the color mark at the slice location.

[0045] In this embodiment of the invention, step S3, which calculates the rotational speed of the turbine shaft based on the pixel height of the color mark at the slice location and obtains the rotational speed signal, includes: Based on the change in pixel height during the continuous acquisition period, the turbine speed n is calculated using the speed calculation formula, with the unit being r / min, to obtain the speed signal. The calculation formula is as follows: in, N For the number of color marks, H The height of the rightmost pixel of the color mark. T The image acquisition period is expressed in seconds. The pixel height of the image slice is acquired during the (n+1)th measurement cycle. The pixel height of the image slice is acquired for the nth measurement cycle.

[0046] Specifically, let the height of the color mark pixel at the slice measured in the nth time be... Let 100 be the height of the color mark pixels at the slice measured in the (n+1)th time. The number of color marks is 900. N The height of the rightmost pixel is 2. H The value is 1000, and the collection cycle is... T The image processor calculates the rotational speed n based on the formula: (The value is 0.4s) To avoid calculation errors, the data collection period is... T When the turbine generator is rotated at its rated speed, the distance traveled by the image recognition area does not exceed the length of a complete color mark, ensuring that the image slices do not skip a complete color mark.

[0047] In an alternative implementation, the rotational speed can also be calculated based on a comparison of the current pixel height with a fixed reference value.

[0048] Specifically, a fixed reference pixel height value is set in the initial measurement cycle. In each subsequent acquisition cycle, the current pixel height of the color mark at the slice is directly measured and compared with the fixed reference value. The rotational speed of the turbine shaft is calculated by using the difference between the current pixel height and the fixed reference value, combined with a preset conversion coefficient.

[0049] In another alternative implementation, the rotational speed can also be calculated based on the determination of the direction of pixel height change.

[0050] Specifically, during the continuous acquisition cycle, the direction of change of the height of the color mark pixels at the slice is monitored, and the rotational speed of the turbine shaft is estimated based on the direction of the pixel height change and a fixed step size value.

[0051] In this embodiment of the application, step S4 outputs the speed signal to the monitoring system and the speed governor. Based on the received speed signal, the monitoring system and the speed governor participate in the control execution to adjust the unit speed, including the following steps B1-B2: B1: The monitoring system consists of five parts: sensors and actuators, data acquisition unit, monitoring host, display and alarm device, and communication network. The various parts of the monitoring system work together to collect, process, control, alarm notification and visualization, while recording and displaying speed data, and performing fault diagnosis and performance analysis.

[0052] B2: The governor is the actuator of the monitoring system. It automatically adjusts the unit speed, distributes the load, prevents overspeed accidents, and ensures the stable operation of the power system. Based on the diagnosis and analysis of the monitoring system, the governor controls and executes in real time to adjust the turbine unit speed.

[0053] Specifically, the system can: regulate the rotational speed by adjusting the water flow rate through the control of the guide vane opening to maintain stable power generation frequency and unit speed; distribute the load by balancing the unit output according to the grid demand to achieve power distribution among multiple units; prevent overspeed by quickly closing the guide vanes when shedding load to avoid the speed from soaring and damaging the equipment; and ensure safety by monitoring abnormalities in real time and triggering protection to ensure the stability of the unit and the grid.

[0054] In an alternative implementation, the speed signal can also be output to a monitoring system, and the monitoring system can adjust the unit speed based on the received speed signal.

[0055] Specifically, the speed signal is output to the monitoring system, which consists of sensors, a data acquisition unit, and a monitoring host. The monitoring system collects and records speed data. The speed governor indirectly receives the speed data through the monitoring host, which then transmits the data to the speed governor via a point-to-point connection.

[0056] In another alternative implementation, the speed signal can be first output to the monitoring system and then sent to the relay unit. Based on the received speed signal, the monitoring system and the speed controller participate in the control execution to adjust the unit speed.

[0057] Specifically, the speed signal is first output to the monitoring system, which consists of sensors, a data acquisition unit, and a monitoring host. The monitoring host processes the speed data, and the processed data is sent to a relay unit via an independent serial data line. The relay unit performs signal format conversion, and the converted signal is then output to the speed governor, which controls the guide vane opening based on this signal.

[0058] In summary, this invention achieves a clear contrast between the color marks and the background environment by uniformly arranging a ring of linearly varying heights around the same diameter circumference of the turbine shaft, facilitating image recognition. An image acquisition device captures images of the color marks at fixed intervals, obtaining a continuous image sequence for non-contact real-time monitoring. The image sequence is output to an image processor for slicing, and the pixel height of the color marks at each slice is read, enabling precise extraction of pixel data. Based on the pixel height of the color marks at each slice, the turbine shaft speed is calculated using a speed calculation formula, yielding a speed signal for accurate and rapid calculation. The speed signal is output to a monitoring system and governor for real-time transmission and integrated control. Based on the received speed signal, the monitoring system and governor participate in control execution, adjusting the unit speed to achieve stable operation and overspeed protection. This invention enables non-contact, high-precision, and electromagnetic interference-resistant measurement of turbine speed, effectively overcoming the problems of high machining accuracy requirements, complex installation, high cost, and difficult maintenance associated with traditional gear disc speed measurement. It improves measurement reliability and economy, and is suitable for low-speed monitoring during start-up and shutdown processes.

[0059] Example 3 is the third embodiment of the present invention, which differs from the previous two embodiments in that: This embodiment also provides a turbine speed measurement system based on image algorithms, including: The color mark arrangement module is responsible for evenly arranging a circle of color marks on the same diameter circumference of the turbine shaft. The color marks are designed with bright colors and obvious contrast with the background environment, and the height changes linearly to ensure that the pixel height changes are clearly captured during image recognition. The image acquisition module acquires images containing color marks at a fixed period T using an image acquisition device, generating a continuous image sequence. The image acquisition device is aligned with the color mark area to ensure that, at the rated speed of the turbine, the distance traversed by the image recognition area within the acquisition period does not exceed the length of a complete color mark. The image processing module receives the image sequence, performs slicing processing, sets the image slice part at a predefined position, performs vertical cutting, and reads the pixel height h of the color mark at the slice. At the same time, based on the change of pixel height in the continuous acquisition period, it uses the rotational speed calculation formula to calculate the turbine speed n and generates the rotational speed signal. The signal output module outputs the speed signal generated by the image processing module to the monitoring system and speed controller, serving as a communication interface to ensure the transmission of the speed signal and real-time control. The monitoring system module consists of five parts: sensors and actuators, data acquisition unit, monitoring host, display and alarm device, and communication network. After receiving the speed signal, it performs data acquisition, processing, control, alarm notification and visualization, while recording and displaying speed data, and performing fault diagnosis and performance analysis. The speed controller module, as the actuator of the monitoring system, automatically adjusts the unit speed, distributes the load, prevents overspeed accidents, and ensures the stable operation of the power system based on the received speed signal.

[0060] This embodiment also provides an electronic device applicable to the measurement of turbine speed based on an image algorithm, comprising: a memory and a processor; the memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions to implement the turbine speed measurement method based on an image algorithm as proposed in the above embodiment.

[0061] This embodiment also provides a storage medium storing a computer program that, when executed by a processor, implements a turbine speed measurement method based on an image algorithm as proposed in the above embodiment.

[0062] The storage medium proposed in this embodiment and the method for measuring the speed of a water turbine based on an image algorithm proposed in the above embodiments belong to the same inventive concept. Technical details not described in detail in this embodiment can be found in the above embodiments, and this embodiment has the same beneficial effects as the above embodiments.

[0063] Based on the above description of the implementation methods, those skilled in the art can clearly understand that the present invention can be implemented using software and necessary general-purpose hardware, and of course, it can also be implemented using hardware. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as a computer floppy disk, read-only memory (ROM), random access memory (RAM), flash memory, hard disk, or optical disk, etc., including several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods of the various embodiments of the present invention.

[0064] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for measuring the rotational speed of a hydraulic turbine based on an image algorithm, characterized in that: The method comprises the following steps: A color mark is arranged on the same diameter circumference of the water turbine main shaft; An image sequence is obtained by collecting the color mark image through an image collector; The image sequence is output to an image processor for slice processing, and the pixel height of the color mark at the slice is read; The rotation speed of the water turbine main shaft is calculated according to the pixel height of the color mark at the slice, and a rotation speed signal is obtained; The rotation speed signal is output to a monitoring system and a speed regulator; The monitoring system and the speed regulator participate in control execution according to the received rotation speed signal, and adjust the rotation speed of the unit.

2. A method of measuring the rotational speed of a hydraulic turbine based on an image algorithm as claimed in claim 1, characterized in that: The color mark is arranged on the same diameter circumference of the water turbine main shaft, which comprises the following steps: The color mark is a complete pattern with different left and right heights, and the color is obviously different from the color of the background environment, and the height changes linearly; The number of color marks is N, and the color marks are uniformly distributed on the same horizontal plane around the main shaft.

3. A method of measuring the rotational speed of a hydraulic turbine based on an image algorithm as claimed in claim 2, characterized in that: The image sequence is obtained by collecting the color mark image through an image collector, which comprises the following steps: The image collector collects the image containing the color mark at a fixed period T, and the image collector is aligned with the color mark area, so that when the water turbine rotates at the rated speed, the distance passed by the image recognition area in the collection period does not exceed the length of a complete color mark; The collected image data is transmitted to the image processor in real time to obtain a continuous image sequence.

4. A method of measuring the rotational speed of a hydraulic turbine based on an image algorithm as claimed in claim 3, characterized in that: The image sequence is output to the image processor for slice processing, and the pixel height of the color mark at the slice is read, which comprises the following steps: The image processor performs slice processing on the collected image sequence, sets the image slice part at the predefined position, performs vertical cutting, and reads the pixel height h of the color mark at the slice.

5. A method of measuring the speed of a hydraulic turbine based on an image algorithm as claimed in claim 4, characterized in that: The rotation speed of the water turbine main shaft is calculated according to the pixel height of the color mark at the slice, and a rotation speed signal is obtained, which comprises the following steps: Based on the change of the pixel height in the continuous collection period, the rotation speed n of the water turbine is calculated using the rotation speed calculation formula, and the rotation speed signal is obtained, the calculation formula is: wherein, N is the number of color scales, H is the pixel height at the right of the color scale, T is the image acquisition period, in s, is the pixel height at the image slice acquired in the n+1th measurement period, is the pixel height at the image slice acquired in the nth measurement period.

6. A method of measuring the speed of a hydraulic turbine based on an image algorithm as claimed in claim 5, characterized in that: The rotation speed signal is output to the monitoring system and the speed regulator, which comprises the following steps: The monitoring system is composed of five parts: sensor and actuator, data acquisition unit, monitoring host, display and alarm device, and communication network; The speed regulator is the execution mechanism of the monitoring system, which automatically adjusts the rotation speed of the unit, distributes the load, prevents overspeed accidents, and ensures the stable operation of the power system.

7. A method of measuring the rotational speed of a hydraulic turbine based on an image algorithm as claimed in claim 6, characterized in that: The monitoring system and the speed regulator participate in control execution according to the received rotation speed signal, and adjust the rotation speed of the unit, which comprises the following steps: The parts of the monitoring system cooperatively perform data acquisition, processing, control, alarm notification and visual display, record and display the rotation speed data, and perform fault diagnosis and performance analysis; The speed regulator controls in real time according to the diagnosis and analysis of the monitoring system, and adjusts the rotation speed of the water turbine unit.

8. A water turbine rotational speed measurement system based on an image algorithm, applying a water turbine rotational speed measurement method based on an image algorithm according to any one of claims 1 to 7, characterized in that, The method comprises the following steps: The color mark arrangement module is responsible for arranging a circle of color marks on the same diameter circumference of the water turbine main shaft, and the color mark adopts a design with bright color and obvious contrast with the background environment, and the height changes linearly, so as to ensure that the pixel height change can be clearly captured during image recognition; The image acquisition module collects the image containing the color mark through the image collector at a fixed period T to generate a continuous image sequence, and the image collector is aligned with the color mark area, so that the distance passed by the image recognition area in the collection period does not exceed the length of a complete color mark when the water turbine rotates at the rated speed; The image processing module receives the image sequence, performs slice processing, sets the image slice position at a predefined position, performs vertical cutting, reads the pixel height h of the color scale at the slice, calculates the water turbine speed n based on the change of the pixel height in the continuous acquisition period using a speed calculation formula, and generates a speed signal; The signal output module outputs the speed signal generated by the image processing module to the monitoring system and the speed regulator as a communication interface to ensure the transmission of the speed signal and real-time control; The monitoring system module is composed of a sensor and an actuator, a data acquisition unit, a monitoring host, a display and alarm device, and a communication network, receives the speed signal, performs data acquisition, processing, control, alarm notification, and visual display, records and displays the speed data, and performs fault diagnosis and performance analysis; The speed regulator module, as an actuator of the monitoring system, automatically adjusts the unit speed, distributes the load, prevents overspeed accidents, and ensures the stable operation of the power system according to the received speed signal. 9.A computer device, comprising a memory and a processor, wherein the memory stores a computer program, and the computer device is configured to perform the method according to any one of claims 1-8 when the computer program is executed by the processor. The processor executes the computer program to realize the steps of the water turbine speed measurement method based on the image algorithm in any one of claims 1 to 7.

10. A computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to realize the steps of the water turbine speed measurement method based on the image algorithm in any one of claims 1 to 7.

Images