Hearth temperature measuring system

Abstract

The invention relates to a hearth temperature measuring system, which comprises a video monitoring module, an image monitoring module, an integrated sensor platform and a central processing unit (CPU), and is characterized in that the video monitoring module comprises at least one high-temperature camera, a video signal processing device and a display which are arranged in a boiler hearth; the high-temperature camera collects a flame video in the hearth and transmits the flame video to the display through the video signal processing device; the image monitoring module comprises an image acquisition card, a field programmable gate array (FPGA) and a graphic processing unit (GPU); the image monitoring module is used for acquiring image data in the hearth from a flame video in the hearth and transmitting the image data to the central processing unit (CPU); the integrated sensor platform comprises a plurality of different types of sensors, and each type of sensor is used for collecting operation parameters of the corresponding type of the coal-fired unit and transmitting the operation parameters to the central processing unit; and the central processing unit CPU outputs hearth temperature measurement data through the image data in the hearth and the operation parameters of the coal-fired unit.

Description

Technical Field

[0001] The invention relates to a furnace temperature measurement system and belongs to the technical field of boiler furnace monitoring. Background Art

[0002] Boiler furnace temperature is an important operating parameter of coal-fired units. Real-time monitoring of furnace temperature helps to ensure safe operation of the unit, and effective control of furnace temperature can inhibit the generation of pollutants. Currently, there are furnace temperature measurement technologies such as thermocouple temperature measurement, optical fiber temperature measurement, infrared spectrometer temperature measurement, ultrasonic thermometer temperature measurement and radiation thermometer temperature measurement. Among them, thermocouples have a simple structure and a large temperature measurement range, and are the most common in practical applications. As a carrier for transmitting temperature information, optical fiber has the advantages of high temperature measurement upper limit, high accuracy, and fast dynamic response. The infrared spectrometer measures specific gases (such as CO) in the furnace. 2 ) to determine the temperature. Ultrasonic thermometers measure temperature by the propagation characteristics of sound waves in the furnace, which is a relatively new technology. Radiation thermometers are based on Planck's blackbody radiation law and determine the temperature by measuring the intensity and wavelength of the radiation of an object. Furnace temperature measurement is developing in the direction of non-contact, high-precision, and real-time monitoring.

[0003] The boiler furnace is in a state of high temperature and high pressure, with a lot of smoke and dust, and most furnace temperature measuring instruments will be disturbed. Thermocouples are prone to malfunction when working for a long time in a high temperature environment. Optical fibers are easily contaminated by smoke, water vapor, etc. during transmission, and are easily mechanically damaged in harsh environments, such as wear and breakage. Ultrasonic thermometers are easily affected by temperature gradients, flue gas flow, and combustion background noise in the sound wave propagation path, and are not suitable for measuring furnace temperature. During the combustion process of the boiler, a lot of gas is produced, the composition is very complex, and there is atmospheric interference and absorption. It is difficult to accurately measure the furnace temperature with an infrared spectrometer. Radiation thermometers are easily affected by smoke in the furnace, and particles or gases in the furnace may absorb or scatter radiation, resulting in measurement errors. Summary of the invention

[0004] In order to solve the problems existing in the above-mentioned prior art, the present invention proposes a furnace temperature measurement system, which combines image monitoring and sensor monitoring technologies. The flame image in the furnace is obtained and the corresponding image data is extracted through the image monitoring module, and the operating parameter data of the coal-fired unit is obtained through the integrated sensor platform. The furnace temperature is measured by combining the image data and the operating parameter data, which can realize long-term and stable real-time monitoring of the furnace temperature.

[0005] The technical solution of the present invention is as follows:

[0006] A furnace temperature measurement system, comprising:

[0007] Video monitoring module, image monitoring module, integrated sensor platform and central processing unit CPU, wherein the video monitoring module includes:

[0008] At least one high-temperature camera, a video signal processing device and a display are arranged in the boiler furnace, and the high-temperature camera collects flame video in the furnace and transmits it to the display through the video signal processing device;

[0009] The image monitoring module is used to obtain the image data in the furnace and transmit it to the central processing unit CPU;

[0010] An integrated sensor platform includes several different types of sensors, each type of sensor is used to collect the corresponding type of operating parameters of the coal-fired unit and transmit them to the central processing unit CPU;

[0011] The central processing unit CPU outputs furnace temperature measurement data through the image data in the furnace and various operating parameters of the coal-fired unit.

[0012] As a preferred implementation, the video signal processing device includes:

[0013] Video capture card and video splitter;

[0014] The video capture card is connected to the high temperature camera and is used to convert the video signal into a digital signal and transmit it to the video splitter;

[0015] The video splitter is used to receive the digital signal transmitted by the video capture card and output it to the display. When receiving multiple digital signals, it splices and outputs them, and splits and displays the corresponding multiple digital signals on the display.

[0016] As a preferred implementation, the image monitoring module includes:

[0017] Frame acquisition cards, field programmable gate arrays FPGAs and graphics processing units GPUs;

[0018] The image acquisition card is connected to the video splitter and is used to capture images from the video signal frame by frame;

[0019] The field programmable gate array FPGA is connected to the image acquisition card and is used for preprocessing the image captured by the image acquisition card;

[0020] The graphics processing unit GPU is connected to the field programmable gate array FPGA and is used for extracting image data from the pre-processed image and transmitting the image data to the central processing unit CPU.

[0021] As a preferred embodiment, the sensor is any one of a liquid flow sensor, a gas flow sensor, a thermocouple sensor, an oxygen sensor and a high temperature pressure sensor, or a combination of two or more thereof.

[0022] As a preferred embodiment, it also includes a solid-state drive, which is connected to the central processing unit CPU and is used to receive and store the furnace temperature measurement data output by the central processing unit CPU.

[0023] As a preferred embodiment, a visualization device is further included, which is connected to the solid-state drive and is used to read and display the furnace temperature measurement data stored in the solid-state drive.

[0024] As a preferred embodiment, a plurality of high-temperature cameras are provided, each of which is arranged in the furnace at the same height but in different orientations, and each of the high-temperature cameras has the same shooting area.

[0025] The present invention has the following beneficial effects:

[0026] The present invention provides a furnace temperature measurement system, which indirectly measures the furnace temperature based on the image inside the furnace captured by a high-temperature camera and the operating parameters of the coal-fired unit collected by an integrated sensor platform, wherein the working environment of each sensor and the high-temperature camera is relatively ideal and will not be seriously disturbed, and the temperature measurement system has high stability.

[0027] Additional aspects and advantages of the present invention will be set forth in the following description, and some of them will be apparent from the description, or may be understood by practicing the present invention. In addition, the various aspects and advantages of the present invention may be realized and obtained by the modules, units, devices and combinations specifically pointed out in the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A schematic diagram of the system structure provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] It should be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0031] The terms “include” and “comprising” indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0032] The term "and / or" means and includes any and all possible combinations of one or more of the associated listed items.

[0033] See also Figure 1 , this embodiment provides a furnace temperature measurement system, including:

[0034] Video monitoring module, image monitoring module, integrated sensor platform and central processing unit CPU, wherein the video monitoring module includes:

[0035] At least one high-temperature camera, a video signal processing device, and a display are arranged in the boiler furnace.

[0036] In one embodiment, the high temperature camera uses an endoscope type high temperature camera, which is used to collect flame video in the furnace and transmit it to the image monitoring module and the display; the endoscope type high temperature camera is a special monitoring equipment used in high temperature environments, which uses wind and water cooling.

[0037] In one embodiment, two high-temperature cameras are set up and installed at the same height but different directions in the furnace. The same area of ​​the furnace is photographed, and the resolution of the captured images is 1912*1088. The two high-temperature cameras shoot together to make the captured images more comprehensive.

[0038] In one embodiment, a high-temperature camera is provided and installed in the top center of the furnace, with the lens pointing downward toward the center of the furnace for shooting.

[0039] In another embodiment, more than two high-temperature cameras are provided, each of which is installed at the same height but different positions in the furnace, and photographs the same area of ​​the furnace.

[0040] It is worth noting that, in any embodiment of the present invention, the area photographed by the high-temperature camera is aimed at the flame area in the furnace, with the purpose of photographing the flame image in the furnace.

[0041] In another embodiment, the rear end of the high-temperature camera is provided with an automatic exit protection device, and when the cooling wind and water are interrupted, the high-temperature camera can exit the high-temperature furnace through the automatic exit protection device.

[0042] In one embodiment, the video signal processing device includes a video capture card and a video splitter, wherein:

[0043] The video capture card is connected to the high temperature camera and is used for converting the video signal transmitted by the high temperature camera into a digital signal and then transmitting it to the video splitter.

[0044] The input end of the video splitter is connected to the video capture card, and is used to receive the digital signal transmitted by the video capture card and output it to the display, and when receiving multiple digital signals, splice and output them, and split and display the corresponding multiple digital signals on the display. For example, in an embodiment where two high-temperature cameras are provided, the video splitter will splice and output the two digital signals corresponding to the two high-temperature cameras to the display, and adopt a 2-split mode to simultaneously display the furnace flame video streams captured by the two high-temperature cameras on the display.

[0045] In one embodiment, the display uses a liquid crystal display screen, which uses a liquid crystal solution between two polarized materials. The electric current affects the arrangement of these liquid crystal molecules, thereby controlling the transmission and blocking of light to form an image, allowing people to intuitively observe the burning of the flame in the furnace.

[0046] The image monitoring module is used to obtain the image data in the furnace from the flame video in the furnace and transmit it to the central processing unit CPU.

[0047] In one embodiment, the image monitoring module includes: an image acquisition card, a field programmable gate array FPGA and a graphics processing unit GPU, wherein:

[0048] The image acquisition card is connected to the video splitter and is used to process the video collected from one or more high-temperature cameras in real time. The furnace flame image is captured from the video taken by one or more high-temperature cameras at the same time at a set frequency of one frame per 4 seconds for subsequent image processing, which helps to save storage space and improve processing efficiency.

[0049] The field programmable gate array FPGA is connected to the image acquisition card and is used for preprocessing the images captured by the image acquisition card.

[0050] In one embodiment, corresponding to the embodiment in which only one high-temperature camera is provided, the image acquisition card only captures one image at a certain working moment; the preprocessing includes graying the image to reduce the computational complexity and improve the efficiency of subsequent processing. And the flame outline in the image is identified by an edge detection algorithm to highlight the edge of the flame for subsequent temperature measurement. In addition, the image preprocessing also includes noise suppression, using filtering technology to remove random noise in the image to ensure the clarity and accuracy of the image. These preprocessing steps provide a solid foundation for subsequent image analysis and temperature measurement. The above preprocessing schemes are all prior art and do not involve improvements in methods / algorithms.

[0051] In another embodiment, corresponding to the embodiment of setting two high-temperature cameras, the image acquisition card captures two flame images at a certain working moment; preprocessing includes real-time image registration of the two images, and the image registration algorithm can be programmed into the field programmable gate array through the hardware description language to achieve high-speed parallel processing. Image registration is a method of achieving information fusion of the two flame images by finding a spatial transformation so that the points corresponding to the same position in the two images correspond one to one. There is a lot of smoke and dust in the furnace, which may cause part of the lens area of ​​the high-temperature camera to be contaminated by smoke and dust, so that the captured image may have small pieces of incompleteness. This processing method can make the two flame images of the same area captured by the two high-temperature cameras complement each other, so as to obtain a more comprehensive furnace flame combustion situation.

[0052] The above-mentioned image registration method is a prior art. For example, the invention patent with publication number "CN206179015U" discloses an image registration control device based on FPGA, and the Chinese invention patent with publication number "CN118037792A" discloses an image registration algorithm based on improved multi-scale ORB. The image registration algorithms used in the above two published patents can be applied to the present embodiment to realize image registration. The present embodiment can be realized by using any image registration algorithm for image fusion disclosed in the prior art, and does not involve improvements in the method.

[0053] In another embodiment, corresponding to the embodiment in which more than two high-temperature cameras are provided, the image acquisition card captures multiple images at a certain working moment; the preprocessing may adopt any one of the above two preprocessing methods, or a combination of the two.

[0054] The graphics processing unit GPU is connected to the field programmable gate array FPGA and is used for extracting image data from the pre-processed image and transmitting the image data to the central processing unit CPU.

[0055] In one embodiment, the extracted image data are parameters such as average brightness, average grayscale, spectral norm, texture features and color moments, which need to be calculated after the image is processed by existing image processing / transformation methods.

[0056] In another embodiment, the extracted image data is image features extracted using an existing feature extraction method, such as a flame image quantitative feature extracted using a semi-supervised extraction method for quantitative features of boiler burner flame images disclosed in the invention patent with publication number "CN111027392A".

[0057] The measuring system can select any one of the image data in the above embodiments and transmit it to the central processing unit CPU.

[0058] The integrated sensor platform includes several different types of sensors, each type of sensor is installed on certain components of the coal-fired unit, and is used to collect the corresponding type of operating parameters of the coal-fired unit and transmit them to the central processor.

[0059] These sensors are installed on certain components of coal-fired boiler units to avoid direct contact with the high temperature and high pressure environment in the furnace, thereby reducing the loss of temperature measuring instruments and lowering production costs.

[0060] In one embodiment, six operating parameters of the coal-fired boiler units are selected based on expert knowledge, including main feed water flow, main steam flow, total air volume, main feed water temperature, oxygen content and reheat steam main pipe pressure; the above six operating parameters of the coal-fired boiler units are measured by a liquid flow sensor, two gas flow sensors, a thermocouple sensor, an oxygen sensor and a high temperature pressure sensor respectively. The integrated sensor platform transmits a set of operating parameter signals of the coal-fired boiler units to the central processing unit CPU every 4 seconds.

[0061] In other embodiments, the selected operating parameters of the boiler coal-fired unit may be several of the above six types, or not limited to the above six types; the sensor may also be several of the above five types, or not limited to the above five types.

[0062] The central processing unit CPU is connected to the integrated sensor platform and the graphics processing unit GPU. The central processing unit CPU is responsible for executing instructions in the program and processing data. In this embodiment, the central processing unit CPU combines the image data in the furnace and the various operating parameters of the coal-fired unit, and then outputs the furnace temperature measurement data. This temperature measurement system utilizes the operating parameter signals transmitted by each sensor and combines the image data of the image in the furnace, which will make the furnace temperature data obtained more accurate.

[0063] In one embodiment, after the central processing unit CPU combines the image data in the furnace and the operating parameters of the coal-fired unit, the method of outputting the furnace temperature measurement data can be a preset empirical model, first normalizing each image data and the operating parameters of the coal-fired unit, and then inputting the normalized image data and the numerical values ​​of the operating parameters of the coal-fired unit through the calculation formula of the empirical model, and outputting the furnace temperature measurement data. The empirical model can adopt any existing model in the prior art that calculates the furnace temperature through image data and the operating parameters of the coal-fired unit, and can also improve the existing model based on expert experience.

[0064] In another embodiment, after the central processing unit CPU merges the image data in the furnace and the various operating parameters of the coal-fired unit, the method of outputting the furnace temperature measurement data can be an AI algorithm, such as using a pre-trained bidirectional long short-term memory network model (BILSTM) prediction program. The bidirectional long short-term memory network model (BILSTM) inputs the historical furnace image data and various operating parameters of the coal-fired unit selected by us during the pre-training process, and iterative training can be completed according to the model prediction value and the actual furnace temperature measurement value. Then, the furnace temperature measurement (prediction) data can be output through the real-time furnace image data and various operating parameters of the coal-fired unit.

[0065] In one embodiment, it also includes a solid-state drive, which is a hard disk made of a solid-state electronic storage chip array. The solid-state drive is connected to the central processing unit CPU and is used to receive and store the furnace temperature measurement data output by the central processing unit CPU.

[0066] In one embodiment, a visualization device is further included, and the visualization device is connected to the solid-state drive. In order to more intuitively observe the temperature change in the furnace, the visualization device reads the furnace temperature measurement data stored in the solid-state drive and displays it. Based on the solid-state drive storing a plurality of historical furnace temperature measurement data, the visualization device can display the furnace temperature measurement data in the form of a line graph, a histogram, a curve graph, etc.

[0067] Based on the above embodiment, the working environment of all equipment in the temperature measurement system is relatively mild, so it can work uninterruptedly for a long time, so that the temperature value of the furnace under any working conditions can be obtained, realizing all-weather monitoring of the furnace temperature of the coal-fired unit.

[0068] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A furnace temperature measurement system, characterized in that: include: Video monitoring module, image monitoring module, integrated sensor platform and central processing unit CPU, wherein the video monitoring module includes: At least one high-temperature camera, a video signal processing device and a display are arranged in the boiler furnace, and the high-temperature camera collects flame video in the furnace and transmits it to the display through the video signal processing device; The image monitoring module is used to obtain the image data in the furnace and transmit it to the central processing unit CPU; An integrated sensor platform includes several different types of sensors, each type of sensor is used to collect the corresponding type of operating parameters of the coal-fired unit and transmit them to the central processing unit CPU; The central processing unit CPU outputs furnace temperature measurement data through the image data in the furnace and various operating parameters of the coal-fired unit.

2. A furnace temperature measurement system according to claim 1, characterized in that: The video signal processing device comprises: Video capture card and video splitter; The video capture card is connected to the high temperature camera and is used to convert the video signal into a digital signal and transmit it to the video splitter; The video splitter is used to receive the digital signal transmitted by the video capture card and output it to the display. When receiving multiple digital signals, it splices and outputs them, and splits and displays the corresponding multiple digital signals on the display.

3. A furnace temperature measurement system according to claim 2, characterized in that: The image monitoring module comprises: Frame acquisition cards, field programmable gate arrays FPGAs and graphics processing units GPUs; The image acquisition card is connected to the video splitter and is used to capture images from the video signal frame by frame; The field programmable gate array FPGA is connected to the image acquisition card and is used for preprocessing the image captured by the image acquisition card; The graphics processing unit GPU is connected to the field programmable gate array FPGA and is used for extracting image data from the pre-processed image and transmitting the image data to the central processing unit CPU.

4. A furnace temperature measurement system according to claim 1, characterized in that: The sensor is any one of a liquid flow sensor, a gas flow sensor, an oxygen sensor, a thermocouple sensor and a high temperature pressure sensor, or a combination of two or more thereof.

5. A furnace temperature measurement system according to claim 1, characterized in that: It also includes a solid state drive, which is connected to the central processing unit CPU and is used to receive and store the furnace temperature measurement data output by the central processing unit CPU.

6. A furnace temperature measurement system according to claim 5, characterized in that: The system also includes a visualization device, which is connected to the solid-state drive and is used to read the furnace temperature measurement data stored in the solid-state drive and display the data.

7. A furnace temperature measurement system according to claim 1, characterized in that: There are multiple high-temperature cameras, each of which is arranged in the furnace at the same height but in different directions, and the shooting areas of each high-temperature camera are the same.

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