Fault detection method and device for power transformer based on infrared thermal imaging technology

Abstract

The invention relates to a fault detection method and device for a power transformer based on an infrared thermal imaging technology, and relates to the technical field of fault detection. The method comprises the following steps: identifying a target area where a to-be-detected power transformer in a power system is located; performing infrared detection on the target area based on an infrared thermal imaging technology to obtain a temperature distribution thermal image shown outside the to-be-detected power transformer; performing temperature analysis on the temperature distribution thermogram according to a pre-trained temperature analysis model to obtain a temperature analysis result; and determining fault information of the power transformer to be detected according to the temperature information of each component in the power transformer. By adopting the method, the detection accuracy of the power transformer in the power system can be improved.

Description

Technical Field

[0001] The present application relates to the field of fault detection technology, and in particular to a method, device, computer equipment, computer-readable storage medium and computer program product for fault detection of power transformers based on infrared thermal imaging technology. Background Art

[0002] During the operation of the power station, operators use portable infrared thermal imagers to regularly inspect the main transformer equipment, which is time-consuming and labor-intensive, untimely, and lacks data continuity. Due to the inconvenience in use and defects in the method, it is difficult to meet the power station's growing requirements for system real-time, economy, safety, reliability, and ease of use.

[0003] For example, for internal faults of power transformers, it is difficult to detect internal faults of transformers directly using infrared thermal imagers, because infrared rays can hardly penetrate insulating materials and equipment casings. Therefore, the current detection methods for transformers in power systems have the problem of low detection accuracy. Summary of the invention

[0004] Based on this, it is necessary to provide a method, device, computer equipment, computer-readable storage medium and computer program product for fault detection of power transformers based on infrared thermal imaging technology, which can improve the detection accuracy of power transformers in power systems in response to the above technical problems.

[0005] In a first aspect, an embodiment of the present application provides a method for detecting faults of a power transformer based on infrared thermal imaging technology. The method comprises:

[0006] Identify a target area where a power transformer to be detected in the power system is located; the target area includes an area where the entire box of the power transformer to be detected is located, and an area of ​​the external environment of the box;

[0007] Performing infrared detection on the target area based on infrared thermal imaging technology to obtain a temperature distribution thermal image of the external appearance of the power transformer to be detected; the temperature distribution thermal image is used to display the external thermal field distribution of the power transformer to be detected;

[0008] Performing temperature analysis on the temperature distribution thermal image according to a pre-trained temperature analysis model to obtain a temperature analysis result; the temperature analysis result includes temperature information of each component in the power transformer;

[0009] According to the temperature information of each component in the power transformer, the fault information of the power transformer to be detected is determined; wherein the fault information includes the fault location and the fault cause.

[0010] In one embodiment, determining the fault information of the power transformer to be detected according to the temperature information of each component in the power transformer includes:

[0011] Determine the box temperature of the power transformer to be tested and the temperature of the bell screw in the power transformer to be tested according to the temperature analysis result;

[0012] When the box temperature is greater than the preset temperature and the bell screw temperature is at a preset normal level, it is determined that the fault location of the power transformer to be detected is the box, and the cause of the fault is determined to be local overheating of the box caused by non-magnetic leakage reasons.

[0013] In one embodiment, determining the fault information of the power transformer to be detected according to the temperature information of each component in the power transformer includes:

[0014] Determining the temperature of the iron core in the power transformer to be tested according to the temperature analysis result;

[0015] In a case where a growth value of a local temperature centered on the iron core is greater than a preset temperature growth threshold, the fault information is determined according to the transformer type of the power transformer to be detected.

[0016] In one embodiment, determining the fault information according to the transformer type of the power transformer to be detected includes:

[0017] Identifying the transformer type of the power transformer to be detected;

[0018] When the transformer type of the power transformer to be detected is a dry-type transformer, the fault position of the power transformer to be detected is determined to be the iron core, and the fault cause is determined to be a short circuit between local core sheets or multiple grounding of the core.

[0019] In one embodiment, determining the fault information according to the transformer type of the power transformer to be detected includes:

[0020] Identifying the transformer type of the power transformer to be detected;

[0021] In the case that the transformer type of the power transformer to be detected is an oil-immersed transformer type, a no-load excitation voltage is applied to the power transformer to be detected in a hanging core manner while the body of the power transformer to be detected is exposed, so as to perform infrared detection on the target area again to obtain a new temperature distribution thermal image;

[0022] According to the temperature distribution thermal image, it is determined that the fault position of the power transformer to be detected is the iron core, and the fault cause is determined to be local fault heating of the iron core.

[0023] In one embodiment, the method further comprises:

[0024] Obtaining external abnormal information of the power transformer to be detected in the target area based on image recognition technology;

[0025] Determining temperature information of each component outside the power transformer according to the temperature analysis result;

[0026] Determining fault information existing outside the power transformer according to the external abnormal information and the temperature information of each external component;

[0027] The external fault information includes: a poor external connection fault of a conductor, a fault of a cooling device and an oil circuit system, and an overheating fault caused by eddy current loss generated by magnetic leakage on a transformer-type equipment box.

[0028] In a second aspect, the present application also provides a fault detection device for a power transformer based on infrared thermal imaging technology. The device comprises:

[0029] A target area identification module is used to identify a target area where a power transformer to be detected in a power system is located; the target area includes an area where the entire box of the power transformer to be detected is located, and an area of ​​the external environment of the box;

[0030] A temperature distribution thermographic determination module is used to perform infrared detection on the target area based on infrared thermal imaging technology to obtain a temperature distribution thermographic image of the external appearance of the power transformer to be detected; the temperature distribution thermographic image is used to display the external thermal field distribution of the power transformer to be detected;

[0031] A temperature analysis result determination module performs temperature analysis on the temperature distribution thermal image according to a pre-trained temperature analysis model to obtain a temperature analysis result; the temperature analysis result includes temperature information of each component in the power transformer;

[0032] The fault information determination module is used to determine the fault information of the power transformer to be detected according to the temperature information of each component in the power transformer; wherein the fault information includes the fault location and the fault cause.

[0033] In a third aspect, the present application further provides a computer device. The computer device includes a memory and a processor, the memory stores a computer program, and the processor implements the following steps when executing the computer program:

[0034] Identify a target area where a power transformer to be detected in the power system is located; the target area includes an area where the entire box of the power transformer to be detected is located, and an area of ​​the external environment of the box;

[0035] Performing infrared detection on the target area based on infrared thermal imaging technology to obtain a temperature distribution thermal image of the external appearance of the power transformer to be detected; the temperature distribution thermal image is used to display the external thermal field distribution of the power transformer to be detected;

[0036] Performing temperature analysis on the temperature distribution thermal image according to a pre-trained temperature analysis model to obtain a temperature analysis result; the temperature analysis result includes temperature information of each component in the power transformer;

[0037] According to the temperature information of each component in the power transformer, the fault information of the power transformer to be detected is determined; wherein the fault information includes the fault location and the fault cause.

[0038] In a fourth aspect, the present application further provides a computer-readable storage medium. The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the following steps are implemented:

[0039] Identify a target area where a power transformer to be detected in the power system is located; the target area includes an area where the entire box of the power transformer to be detected is located, and an area of ​​the external environment of the box;

[0040] Performing infrared detection on the target area based on infrared thermal imaging technology to obtain a temperature distribution thermal image of the external appearance of the power transformer to be detected; the temperature distribution thermal image is used to display the external thermal field distribution of the power transformer to be detected;

[0041] Performing temperature analysis on the temperature distribution thermal image according to a pre-trained temperature analysis model to obtain a temperature analysis result; the temperature analysis result includes temperature information of each component in the power transformer;

[0042] According to the temperature information of each component in the power transformer, the fault information of the power transformer to be detected is determined; wherein the fault information includes the fault location and the fault cause.

[0043] In a fifth aspect, the present application further provides a computer program product. The computer program product includes a computer program, and when the computer program is executed by a processor, the following steps are implemented:

[0044] Identify a target area where a power transformer to be detected in the power system is located; the target area includes an area where the entire box of the power transformer to be detected is located, and an area of ​​the external environment of the box;

[0045] Performing infrared detection on the target area based on infrared thermal imaging technology to obtain a temperature distribution thermal image of the external appearance of the power transformer to be detected; the temperature distribution thermal image is used to display the external thermal field distribution of the power transformer to be detected;

[0046] Performing temperature analysis on the temperature distribution thermal image according to a pre-trained temperature analysis model to obtain a temperature analysis result; the temperature analysis result includes temperature information of each component in the power transformer;

[0047] According to the temperature information of each component in the power transformer, the fault information of the power transformer to be detected is determined; wherein the fault information includes the fault location and the fault cause.

[0048] The above-mentioned method, device, computer equipment, storage medium and computer program product for fault detection of power transformers based on infrared thermal imaging technology use infrared thermal imaging technology to detect faults of power transformers, and realize accurate thermal imaging of power transformers and their external environment through comprehensive identification of target areas; the temperature distribution thermal image not only intuitively displays the thermal field distribution of the transformer, but also combines the pre-trained temperature analysis model to perform in-depth fault analysis based on image data to identify the specific fault location and cause, and through the comprehensive analysis of infrared detection of equipment and external temperature distribution thermal images, it realizes the detection of possible internal faults of power transformers, improves the accuracy and timeliness of fault detection, and improves the detection accuracy of transformers in power systems, while reducing the cost and error of manual inspection. Through automatic analysis of thermal images, potential faults can be quickly identified, early warnings can be issued, and the safety and reliability of power equipment can be enhanced. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the related technologies, the drawings required for use in the embodiments or the related technical descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0050] FIG1 is an application environment diagram of a method for detecting faults of a power transformer based on infrared thermal imaging technology in one embodiment;

[0051] Figure 2The figure is a flow chart of a method for detecting a fault of a power transformer based on infrared thermal imaging technology in one embodiment;

[0052] Figure 3 A schematic diagram of a flow chart of a method for detecting a fault of a power transformer based on infrared thermal imaging technology in another embodiment;

[0053] Figure 4 It is a structural block diagram of a fault detection device for a power transformer based on infrared thermal imaging technology in one embodiment;

[0054] FIG. 5 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0055] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0056] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant laws, regulations and standards of relevant countries and regions.

[0057] In one embodiment, as shown in FIG1 , a method for detecting faults of a power transformer based on infrared thermal imaging technology is provided. This embodiment uses the method applied to a terminal as an example. It is understandable that the method can also be applied to a server, and can also be applied to a system including a terminal and a server, and is implemented through the interaction between the terminal and the server. In this embodiment, the method includes the following steps:

[0058] S201, identifying a target area where a power transformer to be detected is located in a power system.

[0059] The target area includes the area where the entire box of the power transformer to be tested is located, as well as the area of ​​the external environment of the box;

[0060] S202, performing infrared detection on the target area based on infrared thermal imaging technology to obtain a thermal image of the temperature distribution of the external appearance of the power transformer to be detected.

[0061] The temperature distribution thermograph is used to display the external thermal field distribution of the power transformer to be inspected.

[0062] For example, the temperature distribution thermograph is an image generated by inspecting the outside of a power transformer based on infrared thermal imaging technology, showing the thermal field distribution of the target area. The temperature data on the transformer surface is captured by an infrared sensor, and the thermograph visually presents the temperature changes in color. High temperature areas usually indicate potential faults or abnormalities, while low temperature areas indicate normal operating conditions. This image can be used to quickly assess the working status of the transformer and help operation and maintenance personnel perform fault diagnosis and preventive maintenance.

[0063] S203, performing temperature analysis on the temperature distribution thermal image according to the pre-trained temperature analysis model to obtain a temperature analysis result.

[0064] Among them, the temperature analysis results include the temperature information of each component in the power transformer.

[0065] Exemplarily, the temperature analysis model can be a model built by a convolutional neural network (CNN), which can effectively identify abnormal temperatures in images of power equipment through hierarchical feature extraction. For thermal images of the temperature distribution of power transformers, CNN can be trained to identify different temperature change characteristics and detect potential faults. For example, by training the model to identify high-temperature areas, it may indicate equipment overload or insulation failure. Combined with thermal images, CNN can automatically detect and classify fault types, helping operation and maintenance personnel to quickly locate problems and formulate corresponding maintenance plans, thereby improving the safety and reliability of the power system.

[0066] S204: Determine the fault information of the power transformer to be detected according to the temperature information of each component in the power transformer.

[0067] The fault information includes the fault location and the fault cause.

[0068] For example, based on the values ​​of some indicators in the fault analysis result, the location of the fault can be determined and the cause of the fault can be inferred.

[0069] In the above-mentioned fault detection method for power transformers based on infrared thermal imaging technology, infrared thermal imaging technology is used to detect faults of power transformers, and accurate thermal imaging of the power transformer and its external environment is achieved through comprehensive identification of the target area; the temperature distribution thermal image not only intuitively displays the thermal field distribution of the transformer, but also combines the pre-trained temperature analysis model to perform in-depth fault analysis based on image data to identify the specific fault location and cause. Through the comprehensive analysis of the infrared detection of the equipment and the external temperature distribution thermal image, the possible internal faults of the power transformer are detected, the accuracy and timeliness of fault detection are improved, the detection accuracy of the transformer in the power system is improved, and the cost and error of manual inspection are reduced. Through the automatic analysis of thermal images, potential faults can be quickly identified, early warnings can be issued, and the safety and reliability of power equipment can be enhanced.

[0070] In one embodiment, fault information of the power transformer to be detected is determined based on temperature information of each component in the power transformer, including: determining the cabinet temperature of the power transformer to be detected and the temperature of the bell screw in the power transformer to be detected based on the temperature analysis result; when the cabinet temperature is greater than a preset temperature and the bell screw temperature is at a preset normal level, determining that the fault location of the power transformer to be detected is the cabinet, and determining that the cause of the fault is local overheating of the cabinet caused by non-magnetic leakage reasons.

[0071] The bell screw is an important component of the power transformer, usually used to fix and support the insulation structure of the transformer. In fault analysis, if the box temperature exceeds the preset threshold and the bell screw temperature is normal, it means that the box may have a local overheating problem.

[0072] Among them, magnetic leakage refers to the failure of the magnetic field to be effectively closed due to poor insulation or short circuit in power equipment such as transformers, resulting in the leakage of magnetic lines of force, which in turn causes energy loss and equipment heating, and may lead to failure or performance degradation.

[0073] For example, detection of local overheating fault of the box caused by non-magnetic leakage. When the surface of the transformer box is overheated, but the bell screw has no signs of heating, this heating sign is generally not caused by eddy currents generated by magnetic leakage of the box, but the result of heat power generated by the internal fault point being conducted to the surface of the box.

[0074] In this embodiment, by obtaining the box temperature and bell screw temperature of the power transformer, the fault location and cause of the transformer can be effectively diagnosed. If the box temperature is too high and the bell screw is normal, it indicates that there is a local overheating problem in the box, and non-magnetic leakage reasons are potential causes. This analysis method improves the accuracy of fault diagnosis, can identify temperature anomalies in a timely manner, and implement targeted maintenance measures, thereby improving the safety and operational reliability of power equipment and reducing downtime and economic losses.

[0075] In one embodiment, fault information of the power transformer to be detected is determined based on temperature information of each component in the power transformer, including: determining the temperature of the iron core in the power transformer to be detected based on the temperature analysis result; when the growth value of the local temperature centered on the iron core is greater than a preset temperature growth threshold, determining the fault information based on the transformer type of the power transformer to be detected.

[0076] The core of the transformer is usually made of silicon steel sheets and is responsible for the conduction of the magnetic field. The increase in core temperature may lead to reduced energy efficiency and insulation aging, accelerating equipment damage. The type of transformer (such as dry-type transformer or oil-immersed transformer) determines its operating temperature characteristics and fault manifestations, affecting the identification and handling strategies of faults.

[0077] In this embodiment, by monitoring the temperature change of the iron core, local overheating and its fault information are timely determined. This method improves the sensitivity and reliability of fault detection, can identify potential problems early, promote timely maintenance, reduce the risk of equipment failure, and extend the service life of the transformer.

[0078] In one embodiment, fault information is determined according to the transformer type of the power transformer to be detected, including: identifying the transformer type of the power transformer to be detected; when the transformer type of the power transformer to be detected is a dry-type transformer type, determining that the fault location of the power transformer to be detected is the iron core, and determining that the cause of the fault is a short circuit between local core sheets or multi-point grounding of the iron core.

[0079] Among them, the transformer type is dry-type transformer or oil-immersed transformer. The dry-type transformer has the characteristics of oil-free medium, uses air as cooling medium, has a compact structure, is environmentally friendly and safe, and is suitable for use in indoor and humid environments.

[0080] For example, a part of the heat power generated by the short circuit between local sheets of the dry-type transformer core can be directly radiated, and the rest can be directly detected externally through heat conduction of adjacent components. Therefore, it can be directly detected by infrared imaging method, and its thermal spectrum is manifested as a local temperature increase centered on the defective part.

[0081] In this embodiment, the location and cause of the core fault are detected by identifying the transformer type and targeting the characteristics of the dry-type transformer. If a local short circuit or multi-point grounding occurs in the core, the equipment may overheat and performance may deteriorate. This solution improves the accuracy of fault diagnosis, ensures that problems are discovered and measures are taken in a timely manner, reduces the occurrence of faults, prolongs the service life of equipment, and ensures the stable operation of the power system.

[0082] In one embodiment, fault information is determined according to the transformer type of the power transformer to be detected, including: identifying the transformer type of the power transformer to be detected; in the case where the transformer type of the power transformer to be detected is an oil-immersed transformer type, applying a no-load excitation voltage to the power transformer to be detected in a core hanging manner with the body of the power transformer to be detected exposed, so as to perform infrared detection on the target area again to obtain a new temperature distribution thermal image; according to the temperature distribution thermal image, determining that the fault position of the power transformer to be detected is the iron core, and determining that the fault cause is local fault heating of the iron core.

[0083] Among them, oil-immersed transformers use oil as insulation and cooling medium, have good heat dissipation performance and electrical insulation capabilities, are suitable for high-capacity and high-voltage applications, and can operate stably in harsh environments.

[0084] For example, the windings and core of a normally operating oil-immersed transformer are in the middle of the oil tank, and are surrounded by transformer oil. When a local fault occurs inside and generates heat, it will generally not be visible on the outside of the oil tank due to the cooling and diffusion effect of the oil, especially when the core fault is not too serious. Therefore, it is impossible to form a characteristic thermal image with obvious local abnormalities. To perform infrared detection on the core fault of an oil-immersed transformer, a hanging core (or hanging cover) method can be used. When the body of the transformer is exposed, a certain no-load excitation voltage is applied and then an infrared scan is performed. The thermal image characteristics of the oil-immersed transformer after the hanging cover is pressurized are exactly the same as those of the dry-type transformer. Therefore, based on the thermal image characteristics, it is possible to detect whether the core of the oil-immersed transformer has a local fault.

[0085] In this embodiment, the oil-immersed transformer is subjected to infrared detection by applying no-load excitation voltage in the exposed state by using the core hanging method. According to the new temperature distribution thermal image, the core fault and its cause can be accurately identified. This solution improves the sensitivity of fault detection, enables the heat source anomaly to be quickly located, and reduces the risk of accidents. Through timely maintenance, the safety and operating efficiency of the transformer are guaranteed, and the service life of the equipment is extended.

[0086] In one embodiment, the method also includes: identifying external abnormal information of the power transformer to be detected in the target area based on image recognition technology; determining the temperature information of each component outside the power transformer according to the temperature analysis result; and determining the fault information existing outside the power transformer according to the external abnormal information and the temperature information of each external component.

[0087] Among them, the external fault information includes: poor external connection of the conductor, cooling device and oil system failure, and overheating caused by eddy current loss generated by leakage magnetic field on the transformer equipment box.

[0088] Among them, the fault detection of poor external connection of conductor refers to the local overheating caused by increased resistance when the connection between the transformer and the external current-carrying conductor is poor or loose.

[0089] Among them, for the fault detection of cooling device and oil circuit system, the transformer's cooler, submersible oil pump, oil tank, oil pillow, explosion-proof pipe and other cooling devices and oil circuit systems are all outside the transformer. Their faults (whether it is cooling pipe blockage, false oil level or submersible oil pump overheating, etc.) can be clearly displayed directly on the infrared thermal image.

[0090] Among them, overheating caused by eddy current loss generated by leakage magnetic field on the transformer-type equipment box means that due to poor design or manufacturing, the leakage magnetic flux of the transformer will induce an electromotive force on the box shell and form a box circulation with the shell bolts (bell cover screws) as the circulation path, thereby causing local overheating of the box and causing the screw temperature to be too high. In severe cases, it will also affect the normal operation of the transformer.

[0091] In this embodiment, image recognition technology is used to detect external abnormal information of the power transformer, and the temperature information of each component is obtained in combination with the temperature analysis result, so as to comprehensively judge the external fault condition of the transformer; through the combination of vision and temperature monitoring, the accuracy and timeliness of fault identification are improved, potential faults can be discovered early, the risk of equipment downtime is reduced, and maintenance costs are reduced, while the operational safety and reliability of the transformer are improved, ensuring the stability of the power system.

[0092] In another embodiment, Figure 3 As shown, a fault detection method for a power transformer based on infrared thermal imaging technology is provided, comprising the following steps:

[0093] S301, determining the box temperature of the power transformer to be tested and the temperature of the bell screw in the power transformer to be tested according to the temperature analysis result.

[0094] S302, when the box temperature is greater than the preset temperature and the bell screw temperature is at a normal level, determine that the fault location of the power transformer to be detected is the box, and determine that the fault cause is local overheating of the box caused by non-magnetic leakage reasons.

[0095] S303: Determine the temperature of the iron core in the power transformer to be tested according to the temperature analysis result.

[0096] S304: When the increase value of the local temperature centered on the iron core is greater than a preset temperature increase threshold, identify the transformer type of the power transformer to be detected.

[0097] S305, when the transformer type of the power transformer to be detected is a dry-type transformer type, determining that the fault location of the power transformer to be detected is the iron core, and determining that the fault cause is a short circuit between local iron core sheets or multiple grounding of the iron core.

[0098] S306, when the transformer type of the power transformer to be tested is an oil-immersed transformer type, a no-load excitation voltage is applied to the power transformer to be tested in a naked state by adopting a hanging core method, so as to perform infrared detection on the target area again and obtain a new temperature distribution thermal image.

[0099] S307, determining, based on the temperature distribution thermal image, that the fault location of the power transformer to be inspected is the iron core, and determining that the fault cause is local fault heating of the iron core.

[0100] It should be noted that the specific definition of the above steps can be found in the above specific definition of a fault detection method for a power transformer based on infrared thermal imaging technology, which will not be repeated here.

[0101] In one embodiment, the internal faults of the power transformer mainly include defects in the coil, core, lead wire, tap switch, body insulation, bracket, etc. Since infrared rays can hardly penetrate insulating materials and equipment casings, it is difficult to directly detect internal faults of the transformer using an infrared thermal imager.

[0102] Based on this, the embodiment of the present application provides a method for detecting faults of power transformers based on infrared thermal imaging technology. The following is a detailed description of the method for detecting faults of power transformers based on infrared thermal imaging technology using a specific embodiment. It is worth noting that the following description is only an exemplary description and not a specific limitation of the application.

[0103] The present application provides a fault detection method for power transformers based on infrared thermal imaging technology. The characteristics of the internal thermal defects of power transformers are that the process is generally long and the heat is stable. The heat at the fault point can be transferred through convection, radiation or heat transfer from the conductor in contact with the fault point, thereby continuously transferring the heat generated by the internal fault to the outer shell, changing the thermal field distribution on the outer surface of the equipment. This solution can detect whether there is a fault inside the equipment through a comprehensive analysis of the infrared detection of the equipment and the temperature distribution thermal image displayed on the outside. Specifically, it can include:

[0104] (1) Detection of local overheating faults of the box caused by non-magnetic leakage. When the surface of the transformer box is overheated, but the bell screw shows no signs of heating, this heating sign is generally not caused by eddy currents generated by magnetic leakage of the box, but the result of the heat power generated by the internal fault point being transferred to the surface of the box.

[0105] (2) Detection of local heating faults of the core. Local heating faults of the transformer core originate from short circuits between core pieces or multiple grounding of the core. Since the local heating faults of the core caused by these two reasons are all inside the transformer, only dry-type transformers can be tested online by infrared. For oil-immersed transformers, the heat power generated at the fault point often cannot be reflected to the outside, so it can only be tested by applying an appropriate external excitation voltage after the core (cover) is suspended.

[0106] (3) Detection of dry-type transformer core faults. A portion of the heat power generated by a short circuit between local plates in the dry-type transformer core can be directly radiated, and the rest can be directly detected externally through heat conduction of adjacent components. Therefore, infrared imaging methods can be used for direct detection, and the thermal spectrum shows a local temperature increase centered on the defective part.

[0107] (4) Detection of core faults in oil-immersed transformers. The windings and core of a normally operating oil-immersed transformer are located in the middle of the oil tank, surrounded by transformer oil. When a local fault occurs inside and generates heat, it will not be visible on the outside of the oil tank due to the cooling and diffusion effect of the oil, especially when the core fault is not too serious. Therefore, it is impossible to form a characteristic thermal image with obvious local abnormalities. To perform infrared detection of core faults in oil-immersed transformers, a hanging core (or hanging cover) method can be used. When the body of the transformer is exposed, a certain no-load excitation voltage is applied and then an infrared scan is performed. The thermal image characteristics of the oil-immersed transformer after the cover is pressurized are exactly the same as those of the dry-type transformer. Therefore, based on the thermal image characteristics, it is possible to detect whether the core of the oil-immersed transformer has a local fault.

[0108] The present application provides a fault detection method for power transformers based on infrared thermal imaging technology. Through comprehensive analysis of infrared detection of equipment and external temperature distribution thermal images, it is possible to accurately detect possible internal faults of power transformers using infrared thermal imaging technology.

[0109] In addition, the fault detection method for power transformers based on infrared thermal imaging technology provided by the present application can also realize the detection of the outside of the power transformer. Transformer external faults mainly refer to faults that occur in the equipment parts that can be directly observed by the outside world. They mainly include poor conductor connection, box eddy current caused by magnetic leakage, and cooling device failure. Since this type of fault is outside the transformer, infrared thermal imaging detection of the fault does not require advanced technology. It is enough to intuitively find the overheating part based on the infrared thermal image and measure the highest temperature for analysis and evaluation. Specifically including:

[0110] (1) Fault detection of poor external conductor connection. When the transformer is poorly connected or loosely connected to the external current-carrying conductor, local overheating occurs due to increased resistance.

[0111] (2) Cooling device and oil system fault detection. The transformer's cooler, submersible oil pump, oil tank, oil pillow, explosion-proof pipe and other cooling devices and oil systems are all outside the transformer. Their faults (whether it is cooling pipe blockage, false oil level or submersible oil pump overheating, etc.) can be clearly displayed directly on the infrared thermal image.

[0112] (3) Overheating caused by eddy current loss caused by leakage magnetic field on the transformer housing. Due to poor design or manufacturing, the leakage magnetic flux of the transformer will induce electromotive force on the housing and form a housing circulation with the housing bolts (bell screw) as the circulation path, thus causing local overheating of the housing and excessively high screw temperature. In severe cases, it will also affect the normal operation of the transformer.

[0113] It should be understood that, although the various steps in the flowcharts involved in the above-mentioned embodiments are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps does not have a strict order restriction, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above-mentioned embodiments can include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.

[0114] Based on the same inventive concept, the embodiment of the present application also provides a device for detecting faults of power transformers based on infrared thermal imaging technology for realizing the method for detecting faults of power transformers based on infrared thermal imaging technology mentioned above. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme recorded in the above method, so the specific limitations in the embodiments of one or more devices for detecting faults of power transformers based on infrared thermal imaging technology provided below can refer to the limitations of the method for detecting faults of power transformers based on infrared thermal imaging technology above, and will not be repeated here.

[0115] In one embodiment, Figure 4 As shown, a fault detection device for a power transformer based on infrared thermal imaging technology is provided, comprising: a target area recognition module 401, a temperature distribution thermal image determination module 402, a fault analysis result determination module 403, and a fault information determination module 404, wherein:

[0116] The target area identification module 401 is used to identify the target area where the power transformer to be detected in the power system is located; the target area includes the area where the entire box of the power transformer to be detected is located, and the area of ​​the external environment of the box;

[0117] The temperature distribution thermographic determination module 402 is used to perform infrared detection on the target area based on infrared thermal imaging technology to obtain a temperature distribution thermographic image of the external appearance of the power transformer to be detected; the temperature distribution thermographic image is used to display the external thermal field distribution of the power transformer to be detected;

[0118] The temperature analysis result determination module 403 is used to perform temperature analysis on the temperature distribution thermal image according to the pre-trained temperature analysis model to obtain the temperature analysis result; the temperature analysis result includes the temperature information of each component in the power transformer;

[0119] The fault information determination module 404 is used to determine the fault information of the power transformer to be detected according to the temperature information of each component in the power transformer; wherein the fault information includes the fault location and the fault cause.

[0120] In one embodiment, the device is used to: obtain the cabinet temperature of the power transformer to be tested and the temperature of the bell screw in the power transformer to be tested according to the fault analysis results; when the cabinet temperature is greater than the preset temperature and the bell screw temperature is at a normal level, determine that the fault location of the power transformer to be tested is the cabinet, and determine that the cause of the fault is local overheating of the cabinet caused by non-magnetic leakage reasons.

[0121] Each module in the above-mentioned fault detection device for power transformer based on infrared thermal imaging technology can be implemented in whole or in part by software, hardware and their combination. Each of the above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory in the computer device in the form of software, so that the processor can call and execute the corresponding operations of each of the above modules.

[0122] In one embodiment, a computer device is provided, which may be a terminal, and its internal structure diagram may be shown in FIG5. The computer device includes a processor, a memory, an input / output interface, a communication interface, a display unit, and an input device. The processor, the memory, and the input / output interface are connected via a system bus, and the communication interface, the display unit, and the input device are connected to the system bus via the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be implemented through WIFI, a mobile cellular network, NFC (near field communication) or other technologies. When the computer program is executed by the processor, a fault detection method for a power transformer based on infrared thermal imaging technology is implemented.

[0123] Those skilled in the art will understand that the structure shown in FIG. 5 is merely a block diagram of a partial structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than shown in the figure, or combine certain components, or have a different arrangement of components.

[0124] In one embodiment, a computer device includes a memory and a processor. The memory stores a computer program. When the processor executes the computer program, the steps in the above method embodiments are implemented.

[0125] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps in the above-mentioned method embodiments are implemented.

[0126] In one embodiment, a computer program product is provided, including a computer program, which implements the steps in the above method embodiments when executed by a processor.

[0127] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. Non-relational databases may include distributed databases based on blockchains, etc., but are not limited to this. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but are not limited to this.

[0128] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0129] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A fault detection method for power transformer based on infrared thermal imaging technology, characterized in that: The method comprises: Identify a target area where a power transformer to be detected in the power system is located; the target area includes an area where the entire box of the power transformer to be detected is located, and an area of ​​the external environment of the box; Performing infrared detection on the target area based on infrared thermal imaging technology to obtain a temperature distribution thermal image of the external appearance of the power transformer to be detected; the temperature distribution thermal image is used to display the external thermal field distribution of the power transformer to be detected; Performing temperature analysis on the temperature distribution thermal image according to a pre-trained temperature analysis model to obtain a temperature analysis result; the temperature analysis result includes temperature information of each component in the power transformer; According to the temperature information of each component in the power transformer, the fault information of the power transformer to be detected is determined; wherein the fault information includes the fault location and the fault cause.

2. The method according to claim 1, characterized in that The step of determining the fault information of the power transformer to be detected based on the temperature information of each component in the power transformer comprises: Determine the box temperature of the power transformer to be tested and the temperature of the bell screw in the power transformer to be tested according to the temperature analysis result; When the box temperature is greater than the preset temperature and the bell screw temperature is at a preset normal level, it is determined that the fault location of the power transformer to be detected is the box, and the cause of the fault is determined to be local overheating of the box caused by non-magnetic leakage reasons.

3. The method according to claim 1, characterized in that The step of determining the fault information of the power transformer to be detected based on the temperature information of each component in the power transformer comprises: Determining the temperature of the iron core in the power transformer to be tested according to the temperature analysis result; In a case where a growth value of a local temperature centered on the iron core is greater than a preset temperature growth threshold, the fault information is determined according to the transformer type of the power transformer to be detected.

4. The method according to claim 3, characterized in that The step of determining the fault information according to the transformer type of the power transformer to be detected includes: Identifying the transformer type of the power transformer to be detected; When the transformer type of the power transformer to be detected is a dry-type transformer, the fault position of the power transformer to be detected is determined to be the iron core, and the fault cause is determined to be a short circuit between local core sheets or multiple grounding of the core.

5. The method according to claim 3, characterized in that: The step of determining the fault information according to the transformer type of the power transformer to be detected includes: Identifying the transformer type of the power transformer to be detected; In the case that the transformer type of the power transformer to be detected is an oil-immersed transformer type, a no-load excitation voltage is applied to the power transformer to be detected in a hanging core manner while the body of the power transformer to be detected is exposed, so as to perform infrared detection on the target area again to obtain a new temperature distribution thermal image; According to the temperature distribution thermal image, it is determined that the fault position of the power transformer to be detected is the iron core, and the fault cause is determined to be local fault heating of the iron core.

6. The method according to claim 1, characterized in that The method further comprises: Obtaining external abnormal information of the power transformer to be detected in the target area based on image recognition technology; Determining temperature information of each component outside the power transformer according to the temperature analysis result; Determining fault information existing outside the power transformer according to the external abnormal information and the temperature information of each external component; The external fault information includes: a poor external connection fault of a conductor, a fault of a cooling device and an oil circuit system, and an overheating fault caused by eddy current loss generated by magnetic leakage on a transformer-type equipment box.

7. A fault detection device for power transformer based on infrared thermal imaging technology, characterized in that: The device comprises: A target area identification module is used to identify a target area where a power transformer to be detected in a power system is located; the target area includes an area where the entire box of the power transformer to be detected is located, and an area of ​​the external environment of the box; A temperature distribution thermographic determination module is used to perform infrared detection on the target area based on infrared thermal imaging technology to obtain a temperature distribution thermographic image of the external appearance of the power transformer to be detected; the temperature distribution thermographic image is used to display the external thermal field distribution of the power transformer to be detected; A temperature analysis result determination module performs temperature analysis on the temperature distribution thermal image according to a pre-trained temperature analysis model to obtain a temperature analysis result; the temperature analysis result includes temperature information of each component in the power transformer; The fault information determination module is used to determine the fault information of the power transformer to be detected according to the temperature information of each component in the power transformer; wherein the fault information includes the fault location and the fault cause.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 6 are implemented.

9. 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 6 are implemented.

10. A computer program product, comprising a computer program, 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 6 are implemented.

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