A helium detection system for a gas tank of an air charging cabinet

Abstract

The application relates to the technical field of helium detection, and particularly discloses a helium detection system for a gas tank of a gas-filled cabinet, which comprises a pretreatment module, an infrared monitoring module and a leakage positioning module; the pretreatment module is used for establishing a standardized detection environment, uniformly coating a low-thermal-conductivity coating on the surface of the gas tank, and heating the surface of the gas tank by partitioned temperature control; the infrared monitoring module is used for dynamically identifying temperature abnormalities and generating a theoretical infrared thermogram under a no-leakage state according to heating parameters; and the leakage positioning module is used for accurately determining the coordinates of a leakage point; the application greatly shortens the leakage point checking time, reduces the labor cost, avoids blind maintenance of the gas-filled cabinet gas tank, improves the product maintenance efficiency and reliability, prolongs the service life, timely eliminates the safety hazards caused by leakage, is suitable for the whole process of production and maintenance of the gas-filled cabinet gas tank, and has strong practicability and popularization value in the field of helium detection.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of helium detection, and particularly relates to a helium detection system for gas tank of gas-filled cabinet. BACKGROUND

[0002] In the production and maintenance process of the gas tank of the gas-filled cabinet, the traditional helium detection method faces significant technical bottlenecks. Although this method can initially determine whether the product has a leak, when the system determines that a product is unqualified, it is often only known that there is a leak in the whole. Since the diameter of helium molecules is extremely small (about 0.05 nm), the penetration ability is stronger than other gases, even if there is a nanoscale crack, it will also cause escape, so it is difficult to accurately locate the specific leak point position. Due to the lack of accurate positioning guidance, technicians have to spend a lot of time and effort to conduct blind investigation, which greatly reduces the maintenance efficiency and increases the labor cost, not only affects the reliability and service life of the product, but also may cause safety hazards.

[0003] The root cause of these problems lies in the limitations of the traditional helium detection system. The traditional helium detection system can usually only provide macroscopic leakage information and cannot accurately identify and locate small leaks. In the complex structure of the gas tank of the gas-filled cabinet, potential leaks may be hidden in places such as welds, sealing gaskets, or connection parts that are not easy to detect, and the traditional method is difficult to effectively capture these subtle signals. SUMMARY

[0004] The purpose of the present application is to provide a helium detection system for the gas tank of the gas-filled cabinet, which solves the following technical problems.

[0005] The purpose of the present application can be achieved by the following technical solutions:

[0006] A helium detection system for the gas tank of the gas-filled cabinet, comprising:

[0007] A preprocessing module: including a coating unit and a warming unit, the coating unit is used for uniformly applying a low thermal conductivity coating on the surface of the gas tank of the gas-filled cabinet, and the warming unit is used for directional heating of the surface area of the gas tank of the gas-filled cabinet;

[0008] An infrared monitoring module: according to the directional heating, a predicted infrared image of the gas tank of the gas-filled cabinet under no leakage condition is obtained; and the infrared image of the surface of the gas tank of the gas-filled cabinet is obtained in real time, the infrared image is compared with the predicted infrared image, and the area with abnormal temperature gradient line on the infrared image is screened out, which is recorded as an abnormal area;

[0009] The leakage positioning module: a background area of the determined abnormal area is obtained, the temperature change rates of the determined abnormal area and the background area are obtained respectively, and are recorded as a first rate and a second rate respectively; if the rate difference between the first rate and the second rate exceeds a preset difference threshold, the coordinates of the leakage point in the abnormal area are determined.

[0010] As a further scheme of the present application: the low-thermal-conductivity coating comprises an aerogel composite coating, an epoxy-based composite coating and a silicone-based coating.

[0011] As a further scheme of the present application: the process of directional heating comprises:

[0012] An ambient temperature of a current gasholder gas tank is obtained and recorded as T, a heating temperature range [T+5℃, 60℃] is set, a gradient number threshold n is set, n temperature values are selected at equal intervals in the heating temperature range, the gasholder gas tank is divided into n independent intervals, the n temperature values are sequentially corresponding to each independent interval from large to small, and the temperature of each independent interval is heated to the corresponding temperature value.

[0013] As a further scheme of the present application: the process of dividing the gasholder gas tank into n independent intervals comprises:

[0014] The center points of two bottom surfaces of the gasholder gas tank are obtained, a line segment is used to connect the two center points to obtain an axis of the gasholder gas tank, a starting point is selected at any point on the surface of the gasholder gas tank, a division line is obtained by starting from the starting point and winding around the gasholder gas tank once, the division line forms a cross section perpendicular to the axis, and n+1 division lines are selected at equal intervals on the surface of the gasholder gas tank, each adjacent two division lines form an independent interval on the surface of the gasholder gas tank.

[0015] The cross section formed by the division line is obtained by assuming that the gasholder gas tank is cut along the division line.

[0016] As a further scheme of the present application: the process of obtaining the predicted infrared image comprises:

[0017] Three-dimensional data, material data and environmental data of the gasholder gas tank are obtained based on laser scanning, the three-dimensional data includes size, curvature and weld position, the material data includes the thermal conductivity coefficient of the material of the gasholder gas tank and the thermal conductivity coefficient of the low-thermal-conductivity coating, and the environmental data includes ambient temperature and airflow speed in the environment.

[0018] The three-dimensional model of the gas tank of the gas-filled cabinet is established according to the three-dimensional data, the three-dimensional model is divided into a plurality of grid units, and material data is assigned to each grid unit; based on the Fourier heat conduction law, the temperature values of each network unit are obtained according to the environmental data, the global temperature distribution data of the gas tank of the gas-filled cabinet are obtained according to the temperature values of each network unit; the parameters of the infrared thermal imager are obtained, the global temperature distribution data are converted into an infrared image format according to the parameters of the infrared thermal imager, and a predicted infrared image is obtained, the parameters including resolution, temperature measurement range and palette type.

[0019] As a further scheme of the present application: the process of screening out the temperature gradient line abnormal area on the infrared image includes:

[0020] A gradient line number threshold N is set, N temperature gradient lines are marked on the predicted infrared image, denoted as predicted temperature gradient lines, and N temperature gradient lines are marked on the infrared image; each predicted temperature gradient line is numbered, and each temperature gradient line is numbered in the same way; for the predicted temperature gradient line and the temperature gradient line with the same number, a plurality of reference points are selected at equal intervals on the predicted temperature gradient line and the temperature gradient line, each reference point on the predicted temperature gradient line is numbered, denoted as reference point number, and each reference point on the temperature gradient line is numbered in the same way.

[0021] A reference point is selected on the predicted temperature gradient line and the temperature gradient line respectively, two reference points are obtained, if the reference point numbers of the two reference points are the same, and the Euclidean distance between the two reference points is less than a preset distance threshold, then the two reference points are both denoted as abnormal points; if there is a point set composed of m adjacent abnormal points, the area occupied by the point set on the surface of the gas-filled cabinet is obtained, denoted as the temperature gradient line abnormal area, wherein m is a preset abnormal point number threshold, and m≥5.

[0022] As a further scheme of the present application: the process of determining the background area includes:

[0023] The independent interval where the abnormal area is located is obtained, all the abnormal areas are excluded on the independent interval, and all the remaining areas are denoted as the background area.

[0024] As a further scheme of the present application: the process of obtaining the temperature change rate of the background area includes:

[0025] m points in the background area are selected, denoted as background reference points; a monitoring time period is set, the temperature of all the background reference points is obtained every preset time interval t within the monitoring time period, and then the temperature change rate of the background area, i.e. the second rate , is obtained, wherein Tem i represents the temperature of the i-th background reference point, i∈[1, m] and i is a positive integer.

[0026] The beneficial effects of the present application are:

[0027] The gas tank helium detection system of the present application solves the core pain points of traditional helium detection methods, such as difficulty in accurately positioning the leakage point and low maintenance efficiency, through multi-module collaborative design, and has significant technical and application value. From the technical point of view, the low thermal conductivity coating and directional heating design of the preparation module can reduce environmental interference and build a stable and controllable temperature field, laying a precise foundation for subsequent detection; the infrared monitoring module generates predicted infrared imaging based on laser scanning three-dimensional data and Fourier heat conduction law, compares real-time imaging with predicted imaging, filters abnormal temperature gradient lines in the area, and realizes preliminary accurate locking of the leakage area; the leakage positioning module verifies the temperature change rate difference between the background area and the abnormal area, and determines the coordinates of the leakage point through grid division in the rectangular coordinate system, completely getting rid of the limitations of traditional methods "knowing leakage but not knowing position", and accurately positioning the micro leakage points such as nanoscale cracks. From the application point of view, the system greatly shortens the leakage point troubleshooting time, reduces labor costs, avoids blind maintenance of the gas tank, not only improves the product maintenance efficiency and reliability, prolongs the service life, but also eliminates the safety hazards caused by leakage in time, and is suitable for the whole process of gas tank production and maintenance, and has strong practicality and popularization value in the field of helium detection. BRIEF DESCRIPTION OF DRAWINGS

[0028] The present application will be further described below in conjunction with the accompanying drawings.

[0029] Figure 1 is a structural schematic diagram of a gas tank helium detection system of the present application. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0031] Please refer to Figure 1 The present application is a gas tank helium detection system, which comprises:

[0032] The preprocessing module comprises a coating unit and a heating unit, the coating unit is used for uniformly applying a low thermal conductivity coating on the surface of the gas tank, and the heating unit is used for directional heating of the surface area of the gas tank;

[0033] Specifically, since helium is a noble inert gas with very good thermal conductivity, the possible leakage point is determined by monitoring the thermal conductivity of each point on the surface of the gas tank of the gas-filled cabinet;

[0034] The coating unit of the pretreatment module uniformly applies a low-thermal-conductivity coating on the surface of the gas tank of the gas-filled cabinet. The coating type can be selected as an aerogel composite coating, an epoxy-based composite coating, or a silicone-based coating. Such a coating can significantly reduce the heat exchange efficiency between the surface of the gas tank and the external environment, reduce the interference of external factors such as environmental temperature fluctuations and air flow on the temperature field of the surface of the gas tank, and avoid the influence of the thermal conductivity difference of the gas tank substrate on the detection accuracy. The uniform application of the coating ensures that the thermal conductivity of each region on the surface of the gas tank is consistent, preventing temperature field distortion caused by uneven local coating thickness and improving the reliability of the detection reference from the source.

[0035] The heating unit is responsible for the controlled directional heating of the surface of the gas tank. The heating range is set to avoid excessively small temperature differences that make it difficult to identify abnormal temperatures at the leakage point, and to prevent excessively high temperatures that accelerate the aging of the sealing elements of the gas tank and affect the stability of the internal insulating medium. At the same time, the controlled directional heating method creates a non-equilibrium thermodynamic system by artificial construction, converting disordered leakage energy into ordered detectable signals and minimizing thermal noise generated by uniform heating.

[0036] As a preferred embodiment of the present application, the low-thermal-conductivity coating includes an aerogel composite coating, an epoxy-based composite coating, and a silicone-based coating.

[0037] As a preferred embodiment of the present application, the controlled directional heating process includes:

[0038] Obtain the ambient temperature of the current gas tank of the gas-filled cabinet, denoted as T, set the heating temperature range [T+5℃, 60℃], and set the gradient number threshold n. Select n temperature values at equal intervals within the heating temperature range. Divide the gas tank of the gas-filled cabinet into n independent intervals, and correspond the n temperature values from large to small to each independent interval, and heat the temperature of each independent interval to the corresponding temperature value.

[0039] The process of dividing the gas tank of the gas-filled cabinet into n independent intervals includes:

[0040] Obtain the center points of the two bottom surfaces of the gas tank of the gas-filled cabinet, connect the two center points with a line segment to obtain the axis of the gas tank of the gas-filled cabinet. Select a starting point on the surface of the gas tank of the gas-filled cabinet, and obtain a division line by wrapping around the gas tank of the gas-filled cabinet from the starting point. The cross section formed by the division line is perpendicular to the axis. Select n+1 division lines at equal intervals on the surface of the gas tank of the gas-filled cabinet, and each adjacent two division lines form an independent interval on the surface of the gas tank of the gas-filled cabinet.

[0041] The cross section formed by the division line is obtained by assuming that the gas tank is cut along the division line;

[0042] Specifically, the axis is determined by connecting the center points of the two bottom surfaces of the gas tank as a spatial reference, and then a division line is drawn around the tank starting from any point on the surface of the tank, and the cross section formed by the division line is perpendicular to the axis, and then n+1 such division lines are selected at equal intervals, and the independent intervals are formed between adjacent division lines, and the concept of cross section formed by the division line is also provided to assist understanding by assuming that the cross section obtained by cutting the gas tank along the division line, the surface of the gas tank is regularized into an interval that can be independently operated by a standardized geometric partitioning method, which lays a foundation for subsequent partitioning, heating, monitoring and other detection links, and makes the detection more accurate and comparable;

[0043] The infrared monitoring module: according to the control heating, obtaining the predicted infrared imaging of the gas tank in the case of no leakage; and real-time acquisition of the infrared imaging of the surface of the gas tank, comparing the infrared imaging with the predicted infrared imaging, and screening out the area with abnormal temperature gradient line on the infrared imaging, which is recorded as an abnormal area;

[0044] As a preferred embodiment of the present application, the process of obtaining the predicted infrared imaging includes:

[0045] Based on laser scanning, three-dimensional data, material data and environmental data of the gas tank are obtained, the three-dimensional data includes size, curvature and weld position, the material data includes thermal conductivity of the material of the gas tank and thermal conductivity of the low thermal conductivity coating, and the environmental data includes environmental temperature and air flow speed in the environment;

[0046] According to the three-dimensional data, a three-dimensional model of the gas tank is established, the three-dimensional model is divided into a plurality of grid units, and each grid unit is assigned material data; based on Fourier heat conduction law, and according to the environmental data, the temperature value of each network unit is obtained, and according to the temperature value of each network unit, the global temperature distribution data of the gas tank is obtained; the parameters of the infrared thermal imager are obtained, and the global temperature distribution data is converted into infrared image format according to the parameters of the infrared thermal imager, and the predicted infrared imaging is obtained, the parameters include resolution, temperature measurement range and palette type;

[0047] Specifically, first, based on laser scanning technology, three-dimensional point cloud data of the surface of the gas tank of the gas-filled cabinet is acquired, and a high-precision three-dimensional model of the surface of the gas tank is constructed; in combination with the Fourier heat conduction law, the partition heating temperature, the thermal conductivity coefficient of the gas tank material and other parameters set by the input preparation module are input, the conduction process of heat on the surface and inside of the gas tank is simulated, and a predicted infrared image matching the actual detection environment is generated; the image is equivalent to a temperature field benchmark in a state of no leakage, covers the theoretical temperature distribution of each region of the gas tank, and provides a basis for comparison for subsequent anomaly identification, solving the problem that it is difficult to define normal and abnormal temperatures under different environmental temperatures and heating conditions;

[0048] As a preferred embodiment of the present application, the process of screening out the temperature gradient line abnormal region on the infrared image includes:

[0049] A gradient line number threshold N is set, N temperature gradient lines are marked on the predicted infrared image, denoted as predicted temperature gradient lines, and N temperature gradient lines are marked on the infrared image; each predicted temperature gradient line is numbered, and each temperature gradient line is numbered the same; for the predicted temperature gradient line and the temperature gradient line with the same number, a plurality of reference points are selected at equal intervals on the predicted temperature gradient line and the temperature gradient line, each reference point on the predicted temperature gradient line is numbered, denoted as reference point number, and each reference point on the temperature gradient line is numbered the same;

[0050] A reference point is selected on the predicted temperature gradient line and the temperature gradient line respectively, two reference points are obtained, if the reference point numbers of the two reference points are the same, and the Euclidean distance between the two reference points is less than a preset distance threshold, then the two reference points are both denoted as abnormal points; if there is a point set composed of m adjacent abnormal points, the area occupied by the point set on the surface of the gas-filled cabinet is obtained, denoted as the temperature gradient line abnormal region, wherein m is a preset abnormal point number threshold, and m is greater than or equal to 5;

[0051] Specifically, the infrared thermal imager is used to collect the infrared imaging data of the surface of the gas tank of the gas-filled cabinet in real time. The real-time imaging and the predicted imaging are compared in temperature pixel by pixel and region by region, and the image difference value algorithm is used to calculate the temperature difference matrix; for the significant difference area, it is marked as a temperature abnormal candidate area, and the area that may cause temperature field change due to helium leakage is preliminarily screened out, thereby narrowing the leakage investigation range;

[0052] For the temperature anomaly candidate area, the temperature gradient line characteristics are analyzed in depth. Through calculation of the temperature gradient amplitude and direction in the area, a temperature gradient line distribution map is generated. In a normal no-leakage area, the gradient lines should present an orderly distribution consistent with the heat conduction law. In a leakage area, due to the local heat exchange anomaly caused by helium leakage, the gradient lines will appear distortion such as twisting, interruption and convergence. With the aid of a gradient line shape recognition algorithm, the gradient line distribution in the predicted imaging is compared, and the temperature gradient line anomaly area is accurately locked, providing a more focused analysis object for leakage point positioning, greatly improving the accuracy and efficiency of leakage identification, and reducing misjudgment.

[0053] The leakage positioning module: obtaining the background area of the determined abnormal area, obtaining the temperature change rate of the determined abnormal area and the background area respectively, denoted as the first rate and the second rate respectively; if the rate difference between the first rate and the second rate exceeds the preset difference threshold, the coordinates of the leakage point in the abnormal area are determined;

[0054] Specifically, after the infrared monitoring module locks the temperature gradient line abnormal area, the leakage positioning module starts the accurate tracing process. First, the temperature change rate of the abnormal area and the surrounding background area is monitored dynamically, and temperature data at different time periods is collected. The temperature change trend of the two is compared. If the temperature change rate of the abnormal area deviates significantly, it is marked as a high-suspected area. Based on the rectangular coordinate system established by the gas tank three-dimensional model, the abnormal area is gridded, taking the interval division line as the reference, combining the temperature extreme point, i.e. the local temperature minimum or abnormal fluctuation core point, the physical coordinates of the leakage point on the surface of the gas tank are accurately calculated through the coordinate fitting algorithm, and the micro leakage point such as nanoscale crack is quickly positioned, providing accurate position guidance for maintenance, solving the problem of difficult positioning and long repair time of traditional methods, and greatly improving the integrity and repair efficiency of helium leakage detection of the gas tank of the gas-filled cabinet.

[0055] As a preferred embodiment of the present application, the determination process of the background area includes:

[0056] Obtain the independent interval where the abnormal area is located, exclude all abnormal areas on the independent interval, and mark the remaining all areas as the background area;

[0057] As a preferred embodiment of the present application, the obtaining process of the temperature change rate of the background area includes:

[0058] Optionally, m points in the background area are selected, denoted as background reference points; a monitoring time period is set, and the temperature of all background reference points is obtained every preset time interval t in the monitoring time period, and then the temperature change rate of the background area, i.e. the second rate, is obtained , wherein Tem i represents the temperature of the i-th background reference point, i∈[1, m] and i is a positive integer;

[0059] As a preferred embodiment of the present application, if the rate difference between the first rate and the second rate is less than or equal to a preset difference threshold, the temperature change rate of the next abnormal area is monitored;

[0060] As a preferred embodiment of the present application, the determination process of the coordinates of the leakage point comprises:

[0061] A rectangular coordinate system is established on the surface of the gas tank of the gas-filled cabinet, and the surface of the gas tank of the gas-filled cabinet is divided into grids to obtain a plurality of squares, so that the center point of each square corresponds to a coordinate on the rectangular coordinate system; the point with the highest temperature in the abnormal area is obtained and recorded as a leakage point, and the coordinates of the square corresponding to the leakage point are obtained and recorded as the coordinates of the leakage point.

[0062] The above describes one embodiment of the present application in detail, but the content is only a preferred embodiment of the present application and cannot be considered as limiting the scope of the present application. Any equivalent changes and improvements made within the scope of the present application should still belong to the scope of the present application.

Claims

1. A helium detection system for a gas-filled cabinet, characterized in that, include: Pre-treatment module: includes a coating unit and a heating unit. The coating unit is used to uniformly apply a low thermal conductivity coating to the surface of the gas chamber of the gas chamber, and the heating unit is used to control the surface area of ​​the gas chamber of the gas chamber. Infrared monitoring module: Based on the controlled heating, obtain the predicted infrared image of the gas tank under leak-free conditions; and acquire the infrared image of the surface of the gas tank in real time, compare the infrared image with the predicted infrared image, and screen out areas with abnormal temperature gradient lines on the infrared image, which are recorded as abnormal areas. Leakage location module: acquires the background area of ​​the identified abnormal area, and obtains the temperature change rate of the identified abnormal area and the background area respectively, which are denoted as the first rate and the second rate; if the rate difference between the first rate and the second rate exceeds a preset difference threshold, the coordinates of the leak point are determined in the abnormal area.

2. The helium detection system for a gas-filled cabinet according to claim 1, characterized in that, The low thermal conductivity coating includes aerogel composite coating, epoxy composite coating and silicone-based coating.

3. The helium detection system for a gas-filled cabinet according to claim 1, characterized in that, The controlled heating process includes: Obtain the ambient temperature of the current gas chamber of the gas chamber, denoted as T. Then set the heating temperature range [T+5℃, 60℃] and set the threshold number of gradients n. Select n temperature values ​​at equal intervals within the heating temperature range. Divide the gas chamber of the gas chamber into n independent intervals. Assign the n temperature values ​​from largest to smallest to each independent interval and heat each independent interval to the corresponding temperature value.

4. The helium detection system for a gas-filled cabinet according to claim 3, characterized in that, The process of dividing the gas chamber of the gas holder into n independent sections includes: Obtain the center points of the two bottom surfaces of the gas chamber, and connect the two center points with a line segment to obtain the axis of the gas chamber; select any point on the surface of the gas chamber as the starting point, and from the starting point, circle the gas chamber to obtain a dividing line, and the cross-section formed by the dividing line is perpendicular to the axis; select n+1 dividing lines at equal intervals on the surface of the gas chamber, and each pair of adjacent dividing lines forms an independent interval on the surface of the gas chamber. The process of obtaining the cross-section formed by the dividing line is as follows: assuming that the gas tank of the gas chamber is cut along the dividing line, the cross-section obtained is as follows.

5. The helium detection system for a gas-filled cabinet according to claim 1, characterized in that, The process of obtaining the predicted infrared image includes: The three-dimensional data, material data, and environmental data of the gas chamber of the gas holder are obtained by laser scanning. The three-dimensional data includes dimensions, curvature, and weld location. The material data includes the thermal conductivity of the material of the gas chamber and the thermal conductivity of the low thermal conductivity coating. The environmental data includes ambient temperature and airflow velocity in the environment. A three-dimensional model of the gas chamber of the gas holder is established based on the three-dimensional data. The three-dimensional model is divided into several grid units, and material data is assigned to each grid unit. Based on Fourier's law of heat conduction and the environmental data, the temperature value of each grid unit is obtained. Based on the temperature value of each grid unit, the global temperature distribution data of the gas chamber is obtained. The parameters of the infrared thermal imager are acquired, and the global temperature distribution data is converted into an infrared image format based on the parameters of the infrared thermal imager to obtain a predicted infrared image. The parameters include resolution, temperature measurement range, and color palette type.

6. The helium detection system for a gas-filled cabinet according to claim 1, characterized in that, The process of screening out regions with abnormal temperature gradient lines on the infrared image includes: Set a threshold N for the number of gradient lines, mark N temperature gradient lines on the predicted infrared image, denoted as predicted temperature gradient lines, and mark N temperature gradient lines on the infrared image; number each predicted temperature gradient line, and assign the same number to each temperature gradient line; for predicted temperature gradient lines and temperature gradient lines with the same number, select several reference points equally divided by the predicted temperature gradient line and temperature gradient line, number each reference point on the predicted temperature gradient line, denoted as reference point number, and assign the same reference point number to each reference point on the temperature gradient line. Two reference points are obtained by selecting one reference point on the predicted temperature gradient line and one on the temperature gradient line. If the reference point numbers of the two reference points are the same and the Euclidean distance between the two reference points is less than a preset distance threshold, then both reference points are recorded as anomalous points. If there is a set of m adjacent anomalous points, then the area occupied by the set of points on the surface of the gas tank is obtained and recorded as the anomalous area of ​​the temperature gradient line, where m is a preset threshold for the number of anomalous points and m≥5.

7. The helium detection system for a gas-filled cabinet according to claim 1, characterized in that, The process of determining the background area includes: Obtain the independent interval where the abnormal region is located, exclude all abnormal regions in the independent interval, and record all remaining regions as background regions.

8. The helium detection system for a gas-filled cabinet according to claim 1, characterized in that, The process of obtaining the temperature change rate of the background region includes: Select m points randomly within the background area and denote them as background reference points; set a monitoring time period, and acquire the temperature of all background reference points every preset time interval t within the monitoring time period to obtain the temperature change rate of the background area, i.e., the second rate. Tem i Let i represent the temperature of the i-th background reference point, where i ∈ [1, m] and i is a positive integer.

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