Fan brake early warning method and system based on infrared image

Abstract

The invention discloses a fan brake early warning method and system based on an infrared image. The fan brake early warning method comprises the steps that a first feature image of a first object is collected; after the first feature image is preprocessed, feature extraction of a first feature is carried out; according to the extracted features, performing first feature state evaluation on the first object; and generating alarm information according to an evaluation result, and performing early warning. The real-time early warning function effectively reduces the accident risk, prolongs the service life of a brake component, reduces the operation and maintenance cost, and provides technical guarantee for safe and reliable operation of the fan.

Description

Technical Field

[0001] The present invention relates to the technical field of image processing, and in particular to a fan brake warning method and system based on infrared images. Background Art

[0002] In recent years, with the rapid development of the wind power industry, wind turbines, as core equipment, have received widespread attention for their operational safety and reliability. The wind turbine brake system is an important component to ensure the safe shutdown of the wind turbine, but in long-term operation, the brake components are susceptible to factors such as high temperature, wear and aging, and there are serious hidden dangers of failure. Once the brake system fails, it may cause the wind turbine to lose control, and then cause a major safety accident. Therefore, how to achieve efficient monitoring and timely early warning of the wind turbine brake system has become a focus of industry attention. Traditional monitoring methods mainly rely on manual inspection or single sensor data, which makes it difficult to reflect the operating status of the brake system in real time and comprehensively. The brake warning method based on infrared imaging technology takes advantage of non-contact temperature measurement and image analysis, can effectively capture temperature anomalies and component wear characteristics, and provide a scientific basis for the safe operation of wind turbines. Summary of the invention

[0003] In view of the above-mentioned problems, the present invention is proposed.

[0004] In order to solve the above technical problems, the present invention provides the following technical solutions: a fan brake warning method based on infrared images, comprising:

[0005] Acquire a first feature image of a first object;

[0006] After preprocessing the first feature image, extracting the first feature;

[0007] Performing a first feature state evaluation on the first object according to the extracted features;

[0008] Generate alarm information based on the evaluation results and issue early warning.

[0009] As a preferred solution of the infrared image-based fan brake warning method described in the present invention, the first feature image includes image information collected by a device for collecting the first feature.

[0010] As a preferred solution of the infrared image-based wind turbine brake warning method described in the present invention, the preprocessing includes but is not limited to image denoising, image enhancement, and region segmentation.

[0011] As a preferred solution of the infrared image-based fan brake warning method described in the present invention, the feature extraction includes obtaining data describing the first feature according to the characteristics of the first feature.

[0012] As a preferred solution of the infrared image-based fan brake warning method described in the present invention, the first characteristic state includes obtaining an evaluation result of the current state of the first object by analyzing the extracted features.

[0013] As a preferred solution of the infrared image-based wind turbine brake warning method of the present invention, the feature extraction further includes extracting infrared image features from the target area, including but not limited to:

[0014] Temperature distribution feature extraction: The temperature distribution T9x,y) is the temperature value of the point (x,y) on the infrared image of the brake component. The overall evaluation of the original temperature distribution can be calculated by the following formula:

[0015]

[0016] Where, Ω is the braking area of ​​the infrared image;

[0017] Time series change feature extraction: The rate of change of brake temperature within time t is expressed by the following formula:

[0018]

[0019] Temperature difference distribution and gradient characteristics: The spatial gradient of temperature difference can be described by the following expression:

[0020]

[0021] The hot spot area is higher than a certain threshold T th The pixel area Ω h Identification:

[0022] Ω h ={(x,y)∈Ω|T(x,y)>T th}.

[0023] As a preferred solution of the fan brake warning method based on infrared images described in the present invention, wherein: the first characteristic state evaluation is performed on the first object, specifically including combining the temperature distribution characteristics, time change characteristics, temperature gradient characteristics and hot spot area, defined as S, and its expression is:

[0024]

[0025] Among them, α, β, and γ are weighting factors used to adjust the relative importance of temperature gradient, spatial hot spot distribution, and temporal variation; is the temperature gradient, indicating the sensitivity of spatial variation; is the temperature weight function based on Gaussian distribution, which emphasizes the importance of the region close to the average temperature to the overall contribution; |Ω| is the area of ​​the region, which is used for normalization; is the time change rate, which is used to capture abnormal rapid temperature rise; S is the state evaluation index, and the larger the value, the closer the system is to overheating or abnormal state;

[0026] S≥1: indicates that the brake components are in a high-risk state, with abnormal temperature rise or wear;

[0027] 0.5≤S<1: Indicates that the brake components are in a warning state and require regular maintenance;

[0028] S<0.5: Indicates that the brake components are in normal operating condition and no intervention is required.

[0029] A fan brake warning system based on infrared images using the method of the present invention is characterized by:

[0030] A collection unit, collecting a first characteristic image of a first object;

[0031] An extraction unit, which extracts the first feature after preprocessing the first feature image;

[0032] evaluating the source, and performing a first feature state evaluation on the first object according to the extracted features;

[0033] The early warning unit generates alarm information and issues early warning based on the evaluation results.

[0034] A computer device comprises: a memory and a processor; the memory stores a computer program, wherein: the processor implements the steps of any one of the methods of the present invention when executing the computer program.

[0035] A computer-readable storage medium stores a computer program, wherein: when the computer program is executed by a processor, the steps of any one of the methods of the present invention are implemented.

[0036] Beneficial effects of the invention: The infrared image-based wind turbine brake warning method provided by the invention realizes real-time monitoring and intelligent warning of the wind turbine brake system. Non-contact detection improves safety and applicability; multi-dimensional feature extraction enhances the ability to identify early signs of faults; the state assessment model accurately quantifies the risk level, facilitating maintenance decisions; the real-time warning function effectively reduces accident risks, extends the service life of brake components, reduces operation and maintenance costs, and provides technical guarantees for the safe and reliable operation of wind turbines. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use 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 ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0038] Figure 1 An overall flow chart of a fan brake warning method based on infrared images provided for the first embodiment of the present invention. DETAILED DESCRIPTION

[0039] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0040] Example 1, reference Figure 1 , as an embodiment of the present invention, provides a fan brake warning method based on infrared images, comprising:

[0041] S1: Acquire a first feature image of a first object.

[0042] The first feature image includes image information collected by using a device for collecting the first feature.

[0043] In this embodiment, the first object is a fan brake component, the device for collecting the first feature is an infrared collection device, and the first feature image is an infrared image.

[0044] The infrared acquisition device can realize non-contact temperature monitoring by capturing infrared radiation information on the surface of the object. This method avoids direct contact with high-speed rotating or high-temperature brake components, effectively improving the safety and applicability of the detection process, and is particularly suitable for complex operating environments such as fans. During the operation of the brake components, heat is generated due to friction. Abnormal temperature increases usually indicate overheating, wear or potential failures. Infrared images can directly reflect the temperature distribution of brake components, providing intuitive and reliable key features for status assessment.

[0045] In an optional embodiment, the first characteristic image may also be a visible light image, an ultrasonic imaging image or a multispectral image, and the appropriate acquisition method is selected according to different scenarios and needs: Visible light image, applicable scenarios: When the appearance changes of brake parts (such as surface wear, cracks, deformation, etc.) are key monitoring indicators, visible light images can provide clear surface structure information. Ultrasonic imaging image, applicable scenarios: used to detect internal structural defects of brake parts, such as microcracks, bubbles or material stratification. Multispectral image, applicable scenarios: When it is necessary to integrate multiple information (such as thermal radiation, visible light reflection, etc.), multispectral images can combine multi-band data to provide comprehensive analysis. High frame rate thermal imaging image, applicable scenarios: When the focus is on high-speed dynamic changes (such as instantaneous temperature rise or transient behavior of friction), high frame rate thermal imaging can capture rapidly changing temperature fields.

[0046] S2: After preprocessing the first feature image, extract the first feature.

[0047] The preprocessing includes, but is not limited to, image denoising, image enhancement, and region segmentation. The purpose of preprocessing the first feature image is to improve image quality, highlight key information, and provide a reliable data basis for subsequent feature extraction. Since the collected original infrared image may be affected by noise interference, insufficient contrast, or complex background, preprocessing can effectively solve these problems. Among them, image denoising can reduce the impact of environmental interference and equipment noise on the data, ensuring the accuracy of temperature and texture features; image enhancement can highlight the characteristic areas of brake components by improving image contrast or sharpening details, making it easier for feature extraction algorithms to identify key information; region segmentation is used to extract target areas (such as hot spot areas of brake components) from complex backgrounds, focusing on key components and avoiding interference from irrelevant information. Through preprocessing, the accuracy and robustness of image analysis can be significantly improved, laying a good foundation for subsequent feature extraction and state assessment.

[0048] The feature extraction includes obtaining data describing the first feature according to characteristics of the first feature.

[0049] In this embodiment, the feature extraction is to extract infrared image features from the target area, including but not limited to:

[0050] Temperature distribution feature extraction: The temperature distribution T9x,y) is the temperature value of the point (x,y) on the infrared image of the brake component. The overall evaluation of the original temperature distribution can be calculated by the following formula:

[0051]

[0052] Where, Ω is the braking area of ​​the infrared image;

[0053] Time series change feature extraction: The rate of change of brake temperature within time t is expressed by the following formula:

[0054]

[0055] Temperature difference distribution and gradient characteristics: The spatial gradient of temperature difference can be described by the following expression:

[0056]

[0057] The hot spot area is higher than a certain threshold T th The pixel area Ω h Identification:

[0058] Ω h ={(x,y)∈Ω|T(x,y)>T th}.

[0059] In an optional embodiment, the feature extraction can also be to extract the evaluation results of the thermal distribution unevenness, thermal cycle stability, or surface wear state of the brake component. These characteristic states can be further expanded and defined by the following methods: Thermal distribution unevenness, evaluates the uniformity of the surface temperature distribution of the brake component, and reflects whether there is local abnormal temperature rise in the friction component. Calculate the standard deviation or coefficient of variation of the temperature distribution in the infrared image as an indicator of unevenness. High thermal unevenness may indicate local wear of the brake pad or the formation of hot spots, which requires timely attention. Thermal cycle stability, analyzes the regularity of temperature changes of the brake component during multiple working cycles to determine whether the temperature rise is stable. Collect temperature data for multiple time periods and calculate the stability index of the temperature change between cycles (such as mean square error or fluctuation amplitude). A stable thermal cycle indicates that the brake component is in a healthy state, while an unstable cycle may indicate component aging or abnormal load, and so on.

[0060] S3: Performing a first feature state evaluation on the first object according to the extracted features.

[0061] The first feature state includes an evaluation result of the current state of the first object obtained by analyzing the extracted features.

[0062] In this embodiment, the first characteristic state specifically includes combining the temperature distribution characteristics, time variation characteristics, temperature gradient characteristics and hot spot area, which is defined as S, and its expression is:

[0063]

[0064] Among them, α, β, and γ are weighting factors used to adjust the relative importance of temperature gradient, spatial hot spot distribution, and temporal variation; is the temperature gradient, indicating the sensitivity of spatial variation; is the temperature weight function based on Gaussian distribution, which emphasizes the importance of the region close to the average temperature to the overall contribution; |Ω| is the area of ​​the region, which is used for normalization; is the time change rate, which is used to capture abnormal rapid temperature rise; S is the state evaluation index, and the larger the value, the closer the system is to overheating or abnormal state;

[0065] S≥1: indicates that the brake components are in a high-risk state, with abnormal temperature rise or wear;

[0066] 0.5≤S<1: Indicates that the brake components are in a warning state and require regular maintenance;

[0067] S<0.5: Indicates that the brake components are in normal operating condition and no intervention is required.

[0068] S4: Generate alarm information based on the evaluation results and issue an early warning.

[0069] Embodiment 2 is an embodiment of the present invention. This embodiment further provides a fan brake warning system based on infrared images, which includes:

[0070] The collecting unit collects a first characteristic image of the first object.

[0071] The extraction unit performs feature extraction of the first feature after preprocessing the first feature image.

[0072] The evaluation source performs a first feature state evaluation on the first object according to the extracted features.

[0073] The early warning unit generates alarm information and issues early warning based on the evaluation results.

[0074] If the above functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0075] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in conjunction with such instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in conjunction with such instruction execution systems, devices or apparatuses.

[0076] More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or more wires (electronic device), a portable computer disk case (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be a paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, deciphering or, if necessary, processing in another suitable manner, and then stored in a computer memory.

[0077] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0078] Example 3 is an embodiment of the present invention, which provides a fan brake warning method based on infrared images. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through economic benefit calculation and simulation experiments.

[0079] A certain type of wind turbine brake system was selected as the test object. Its brake components are made of carbon fiber reinforced resin-based composite materials with an operating temperature range of -20°C to 120°C. The test environment is a laboratory simulation condition, including standard room temperature (25°C) and high humidity conditions (85% relative humidity). The core equipment used in the experiment includes a high-resolution infrared thermal imager, a simulated wind turbine brake system test platform, and a data acquisition and analysis system.

[0080] Step 1: Infrared image acquisition

[0081] In the simulated wind turbine operation, the brake test platform was used to conduct simulation tests with different braking intensities (light, medium and heavy conditions), and the infrared thermal imager captured the temperature distribution image of the brake components in real time. The data collection interval was 2 seconds and the total collection time was 10 minutes to ensure that the key temperature characteristics of the temperature rise, stabilization and cooling process could be captured.

[0082] Step 2: Image Preprocessing

[0083] The collected infrared images are de-noised by software to eliminate the interference of environmental noise, and the contrast of key areas is enhanced to make the temperature difference change clearer. The brake component area is further segmented to extract the infrared feature areas of the brake disc and brake pad.

[0084] Step 3: Feature Extraction

[0085] The extracted features include: the mean value, standard deviation, hot spot area, temperature gradient, and the rate of temperature change in the time series. Combining the data points of each feature, a time series model is established to focus on analyzing the dynamic changes and spatial distribution of temperature during braking.

[0086] Step 4: Status Assessment

[0087] Based on the extracted features, the state evaluation index S is calculated. In the experiment, the model weight factor is adjusted to optimize the influence weights of temperature gradient, hot spot area and time change to reflect the current state of the brake components. The experimental goal is to identify the brake system with a high-risk state S≥1 and evaluate the accuracy and sensitivity of the early warning model.

[0088] Step 5: Comparative Experimental Design

[0089] To verify the innovation of the present invention, the test results are compared with the traditional thermocouple point temperature monitoring method. The traditional method only monitors the temperature of one or two points, lacks information on spatial distribution and time variation, and has limited ability to identify faults in the early stage.

[0090] Table 1 Data sheet

[0091]

[0092] It can be seen from the test data that the fan brake warning method based on infrared images of the present invention has significant advantages in identifying abnormal status of brake components and early fault warning.

[0093] Compared with the traditional thermocouple point temperature method which only provides single-point temperature information, the present invention collects complete temperature distribution and time series change data through infrared images. For example, under heavy braking conditions, the method detects a temperature standard deviation of 6.5°C and a hot spot area of ​​15.2 cm 2 , which is key information that traditional methods cannot provide. These features can effectively reveal wear, heat accumulation and local overheating of brake components.

[0094] By calculating the state assessment index SSS, the present invention can quantify the state risk of the brake components. For example, under heavy braking conditions, the state assessment index S = 1.2S = 1.2S = 1.2, which clearly indicates that the brake components have entered a high-risk state. In contrast, traditional methods cannot provide risk quantification and rely on the subjective judgment of operators, which may lead to missed faults or misjudgment.

[0095] The present invention captures the dynamic characteristic of temperature change rate. For example, under heavy braking conditions, the temperature change rate reaches 5.5℃ / s, which is significantly higher than normal conditions. The rapid change in the temperature rise rate is an early sign of overheating or abnormal friction, and can provide sufficient warning time for operation and maintenance personnel.

[0096] Through the analysis of the hot spot area of ​​infrared images, it was found that the hot spot area was 8.4cm under medium braking and heavy braking conditions. 2 and 15.2cm 2 , indicating that the local wear or heat accumulation of brake components has intensified. However, traditional methods cannot monitor these spatial distribution characteristics and are prone to overlooking key risk points.

[0097] In summary, the present invention realizes comprehensive monitoring and accurate early warning of brake components by combining infrared image feature extraction and state assessment model. Compared with the existing technology, it has significant creativity and novelty. It not only improves the accuracy of fault identification, but also provides a reliable basis for equipment operation and maintenance, and has high application value.

[0098] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A fan brake warning method based on infrared images, characterized in that: include: Acquire a first feature image of a first object; After preprocessing the first feature image, extracting the first feature; Performing a first feature state evaluation on the first object according to the extracted features; Generate alarm information based on the evaluation results and issue early warning.

2. The fan brake warning method based on infrared image according to claim 1 is characterized in that: The first feature image includes image information collected by using a device for collecting the first feature.

3. The fan brake warning method based on infrared image according to claim 2 is characterized in that: The preprocessing includes, but is not limited to, image denoising, image enhancement, and region segmentation.

4. The fan brake warning method based on infrared image according to claim 3 is characterized in that: The feature extraction includes obtaining data describing the first feature according to characteristics of the first feature.

5. The fan brake warning method based on infrared image according to claim 4 is characterized in that: The first feature state includes an evaluation result of the current state of the first object obtained by analyzing the extracted features.

6. The fan brake warning method based on infrared images as claimed in claim 5 is characterized in that: The feature extraction also includes extracting infrared image features from the target area, including but not limited to: Temperature distribution feature extraction: The temperature distribution T9x,y) is the temperature value of the point (x,y) on the infrared image of the brake component. The overall evaluation of the original temperature distribution can be calculated by the following formula: Where, Ω is the braking area of ​​the infrared image; Time series change feature extraction: The rate of change of brake temperature within time t is expressed by the following formula: Temperature difference distribution and gradient characteristics: The spatial gradient of temperature difference can be described by the following expression: The hot spot area is higher than a certain threshold T th The pixel area Ω h Identification: Ω h ={(x,y)∈Ω∣T(x,y)>T th }。 7. The fan brake warning method based on infrared images as claimed in claim 6 is characterized in that: The first characteristic state evaluation is performed on the first object, specifically including combining the temperature distribution characteristics, time change characteristics, temperature gradient characteristics and hot spot area, which is defined as S, and its expression is: Among them, α, β, and γ are weighting factors used to adjust the relative importance of temperature gradient, spatial hot spot distribution, and temporal variation; is the temperature gradient, indicating the sensitivity of spatial variation; is the temperature weight function based on Gaussian distribution, which emphasizes the importance of the region close to the average temperature to the overall contribution; |Ω| is the area of ​​the region, which is used for normalization; is the time change rate, which is used to capture abnormal rapid temperature rise; S is the state evaluation index, and the larger the value, the closer the system is to overheating or abnormal state; S≥1: indicates that the brake components are in a high-risk state, with abnormal temperature rise or wear; 0.5≤S<1: Indicates that the brake components are in a warning state and require regular maintenance; S<0.5: Indicates that the brake components are in normal operating condition and no intervention is required.

8. A wind turbine brake warning system based on infrared images using the method according to any one of claims 1 to 7, characterized in that: A collection unit, collecting a first characteristic image of a first object; An extraction unit, which extracts the first feature after preprocessing the first feature image; evaluating the source, and performing a first feature state evaluation on the first object according to the extracted features; The early warning unit generates alarm information and issues early warning based on the evaluation results.

9. A computer device comprising: A memory and a processor; the memory stores a computer program, wherein the processor implements the steps of any method as claimed in claim 1 when executing the computer program.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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