Method and system for monitoring gas diffusion in power channel based on sensor array

Abstract

The invention discloses a method and system for monitoring gas diffusion in an electric power channel based on a sensor array, belongs to the technical field of gas diffusion monitoring, and solves the problem of how to monitor the gas diffusion behavior in the electric power channel. The multi-point sensor array is arranged on the section of the power channel, the influence of the obstacle characteristics in the power channel on gas diffusion is considered, the concentration distribution of the section of the power channel is calculated in combination with the gas diffusion rule, and the monitoring model is circularly corrected and perfected, so that theoretical support is provided for gas monitoring and early warning of the power channel; scientific basis is provided for accident prevention and treatment, harm of gas leakage to an electric power system is avoided, and the risk that gas explodes in an electric power channel is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of gas diffusion monitoring, and relates to a method and system for monitoring gas diffusion in a power channel based on a sensor array. Background Art

[0002] In modern urban underground pipe networks, gas pipelines and power pipelines are often laid in parallel or adjacent to each other due to space limitations. Although both pipeline systems follow strict safety specifications in design and construction, due to the flammable and explosive nature of gas and the high voltage risk in power pipelines, there is a potential coupling risk between gas pipeline leakage and the power pipeline system. When gas leaks into the power pipeline, the gas accumulates in the power channel. If the power equipment fails or arcs at this time, it is very easy to cause a gas explosion, which in turn causes a serious safety accident.

[0003] At present, although great progress has been made in the separate monitoring of gas pipelines and power pipelines, there is still a lack of effective monitoring methods for gas leaks into the power pipeline system. For example, the invention patent with application publication number CN114664057A discloses a narrow and confined space gas-electricity monitoring device and monitoring method, which collects gas concentration through a methane sensor, and the data processing unit analyzes the collected gas concentration to determine whether a gas leak occurs, and records the output gas concentration curve. However, it is difficult for the existing technology to detect the process of gas leakage into the power channel in real time, and it is impossible to accurately determine the diffusion path and concentration change of the gas leak. In addition, the existing monitoring system is usually unable to be linked with the power system for control, resulting in the power equipment still operating normally when the gas leaks into the power channel, increasing the risk of gas explosion.

[0004] Existing gas monitoring devices are limited to the pressure and flow detection inside the pipeline, and the existing technical means cannot provide sufficient data support for the diffusion behavior of gas leaking into other spaces, especially after entering the power channel. In addition, since the gas will diffuse with the airflow after entering the power channel, its concentration changes are not easy to be captured by sensors in a single position. Therefore, traditional monitoring methods are difficult to accurately determine the leakage amount, diffusion path and aggregation of gas, and cannot provide timely and effective warnings for preventing explosions.

[0005] With the complexity and aging of urban underground pipeline networks, the coupling risk between gas pipelines and power pipelines has become increasingly prominent. There is an urgent need for a method that can monitor the diffusion behavior of gas in power channels to avoid the harm of gas leakage to the power system and reduce the risk of gas explosion in power channels, providing an effective scientific basis for the formulation of relevant safety standards and protective measures. Summary of the invention

[0006] The technical problem to be solved by the present invention is how to monitor the diffusion behavior of gas in the power channel.

[0007] The present invention solves the above technical problems through the following technical solutions: A method for monitoring gas diffusion in a power channel based on a sensor array comprises the following steps: S1. Divide the power channel into three-dimensional grids and divide the cross section of the power channel into The grid is used to initialize the geometric dimensions of the power channel cross section, and the sensor array is arranged in each grid unit of the power channel cross section, where: represents the number of grids along the x direction, Indicates the number of grids along the z direction; S2. The sensor collects real-time gas concentration information, calculates the gas diffusion coefficient in the power channel, and uses the gas diffusion equation to analyze the change of gas concentration in the power channel; S3. According to the real-time gas concentration information collected by the sensor, the gas concentration gradient and gas diffusion flux of each grid unit in the y direction are calculated based on the difference method and the gas concentration gradient, the gas leakage of each grid unit is calculated, the gas leakage of each grid unit is accumulated in real time, and the total gas leakage of the power channel cross section is calculated; S4. Calculate the relative error based on the gas leakage and the actual leakage. If the relative error is less than 5%, output the current gas diffusion coefficient and gas leakage. If the relative error is greater than or equal to 5%, revise the gas diffusion coefficient, execute S3, and recalculate the gas leakage.

[0008] Furthermore, the following formula is used in S2 to calculate the gas diffusion coefficient in the power channel:

[0009] In the formula, Indicates the gas diffusion coefficient of the current power channel cross section, in units of , is the free diffusion coefficient, is the adjusted free diffusion coefficient, is the damping coefficient.

[0010] Furthermore, the expression of the gas diffusion equation in S2 is as follows:

[0011] In the formula, represents the internal time t and spatial position of the power channel The gas concentration in units of , Represents the spatial second-order partial derivative of gas concentration.

[0012] Furthermore, the gas concentration gradient of each grid unit in the y direction is calculated using the following formula in S3:

[0013] In the formula, Represents the concentration gradient of each grid cell in the y direction, in units of , represents the gas concentration in the grid cell, Indicates the gas concentration outside the grid cell, Indicates the change in the y direction of the unit step of the grid cell.

[0014] Furthermore, the following formula is used in S3 to calculate the gas diffusion flux of each grid unit in the y direction:

[0015] In the formula, Represents the gas diffusion flux of each grid cell in the y direction, in units of ,in , .

[0016] Furthermore, the following formula is used in S3 to calculate the gas leakage of each grid unit:

[0017] In the formula, Represents the gas leakage of each grid unit, Indicates the cross-sectional width of the power channel, Indicates the cross-sectional height of the power channel.

[0018] Furthermore, the total amount of gas leakage in the cross section of the power channel is calculated using the following formula in S3:

[0019] In the formula, It represents the total amount of gas leakage in the cross section of the power channel. T represents the current time. The time when the gas initially leaks into the power channel is 0.

[0020] Furthermore, the relative error is calculated using the following formula in S4:

[0021] In the formula, Relative error, Indicates the total amount of power channel leakage, Indicates the actual leakage amount.

[0022] Furthermore, the gas diffusion coefficient is revised using the following formula in S4:

[0023] In the formula, represents the revised gas diffusion coefficient, Represents the adjustment factor.

[0024] A gas diffusion monitoring system in a power channel based on a sensor array, comprising a sensor array arrangement module, a gas concentration analysis module, a gas diffusion state judgment module and a gas leakage error analysis module; The sensor array arrangement module is used to divide the power channel into three-dimensional grids and divide the cross section of the power channel into The grid is used to initialize the geometric dimensions of the power channel cross section, and the sensor array is arranged in each grid unit of the power channel cross section, where: represents the number of grids along the x direction, Indicates the number of grids along the z direction; The gas concentration analysis module is used for collecting real-time gas concentration information through sensors, calculating the gas diffusion coefficient in the power channel, and analyzing the change of gas concentration in the power channel using the gas diffusion equation; The gas diffusion state judgment module is used to collect real-time gas concentration information according to the sensor, calculate the gas concentration gradient and gas diffusion flux of each grid unit in the y direction based on the difference method and the gas concentration gradient, calculate the gas leakage of each grid unit, accumulate the gas leakage of each grid unit in real time, and calculate the total gas leakage of the power channel cross section; The gas leakage error analysis module is used to calculate the relative error based on the gas leakage amount and the actual leakage amount. If the relative error is less than 5%, the current gas diffusion coefficient and gas leakage amount are output; if the relative error is greater than or equal to 5%, the gas diffusion coefficient is revised, the gas diffusion state judgment module is executed, and the gas leakage amount is recalculated.

[0025] The advantages of the present invention are: The present invention utilizes the gas concentration information collected by the sensor array to monitor the gas diffusion behavior in the power channel. By arranging a multi-point sensor array in the cross section of the power channel, considering the influence of the obstacle characteristics in the power channel on the gas diffusion, the concentration distribution in the cross section of the power channel is calculated in combination with the gas diffusion law, and the monitoring model is improved through cyclic correction, so as to provide theoretical support for gas monitoring and early warning in the power channel, provide a scientific basis for accident prevention and handling, avoid the harm of gas leakage to the power system, and reduce the risk of gas explosion in the power channel. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a flow chart of a method for monitoring gas diffusion in a power channel based on a sensor array according to a first embodiment of the present invention; Figure 2 is a schematic diagram of the arrangement of a sensor array in a power channel according to the first embodiment of the present invention; Figure 3 This is an example diagram of the power channel site of the first embodiment of the present invention. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and specific embodiments: Embodiment 1 like Figure 1 Specifically, a method for monitoring gas diffusion in a power channel based on a sensor array is disclosed, comprising the following steps: S1. Divide the power channel into grids and divide the cross section of the power channel into The geometric dimensions of the power channel cross section are initialized, and the sensor array is arranged in each grid unit of the power channel cross section.

[0029] In this embodiment, the power channel is divided into three-dimensional grids, and the horizontal direction of the power channel cross section is defined as the x direction, the vertical direction of the power channel cross section is defined as the z direction, the extension direction of the power channel is defined as the y direction, and the plane where the power channel cross section is located is defined as the xoz plane. Each grid unit represents the gas concentration of a certain volume unit, and the area of ​​the cables and cable brackets is set as an obstacle area, and the gas cannot pass through.

[0030] In this embodiment, the cross section of the power channel is divided into The grid, represents the number of grids along the x direction, Indicates the number of grids along the z direction, initializes the geometric dimensions of the power channel section, sets the power channel section width to W, height to H, and the cross-sectional area of ​​each grid .

[0031] like Figure 2-3As shown, the power channel includes a cable trench, a power pipeline and a power well (not shown); multiple cable trenches are connected in sequence, the power pipeline is laid in the cable trench, and both ends of the power well are connected to the cable trench; the cable trench is made of stainless steel, and the cable trenches are sealed by rubber rings or welding; mesh covers are set at both ends of the power well to prevent interference from external airflow. Figure 2 As shown, the leakage point E is set at the bottom of the power channel, and the gas diffuses through the leakage point E along the extension direction of the power channel.

[0032] The sensor array is distributed in each grid unit of the power channel cross section, and each sensor can collect the gas concentration data of the grid unit where it is located in real time.

[0033] by Figure 2 For example, in this embodiment, n is taken as 3, and the cross section of the power channel is divided into The sensor array includes an A-side sensor, a central sensor, and a B-side sensor arranged in sequence in the horizontal direction; the A-side sensor includes sensors A1, A2, and A3 arranged in sequence in the vertical direction; the central sensor includes sensors F1, F2, and F3 arranged in sequence in the vertical direction; and the B-side sensor includes sensors B1, B2, and B3 arranged in sequence in the horizontal direction. Based on the data collected by the sensor array, the concentration field of the entire cable trench can be constructed through numerical simulation to analyze the changes in gas concentration in the power channel.

[0034] S2. The sensor collects real-time gas concentration information, calculates the gas diffusion coefficient in the power channel, and uses the gas diffusion equation to analyze the change of gas concentration in the power channel.

[0035] In this embodiment, the expression of the gas diffusion coefficient is as follows:

[0036] In the formula, Indicates the gas diffusion coefficient of the current power channel cross section, in units of , the gas diffusion coefficient will be affected by obstacles (such as cables and cable racks), is the free diffusion coefficient, is the adjusted free diffusion coefficient, is the damping coefficient, take , represents the slowing effect of obstacles on gas diffusion, to simulate the hindering effect in the gas diffusion process. For example, near obstacles, the gas diffusion coefficient will decrease, while in open areas, the gas diffusion coefficient is the free diffusion coefficient value.

[0037] Since obstacles in different areas have different effects on gas diffusion, such as cables and brackets, which are common obstacles in power channels, they will block or slow down the diffusion of gas. By introducing the dynamic diffusion coefficient, that is, adjusting the diffusion coefficient according to the properties of obstacles in different positions, and using the dynamic diffusion coefficient to represent the impact of obstacles on diffusion, it can accurately reflect the actual situation of the gas diffusion process in the power channel, truly simulate the propagation characteristics of gas in the power channel, and improve the prediction ability and accuracy of the model.

[0038] At the same time, changes in the state of obstacles (such as cable movement, bracket removal) will lead to changes in environmental conditions. The present invention adjusts the diffusion coefficient according to the properties of obstacles at different locations, analyzes the gas diffusion under different environmental conditions, and improves the flexibility and adaptability of the analysis of gas concentration changes.

[0039] In this embodiment, the gas diffusion equation is used to simulate the gas diffusion process in the power channel, and is discretized in a three-dimensional grid space by a finite difference method. The expression of the gas diffusion equation is as follows:

[0040] In the formula, represents the internal time t and spatial position of the power channel The gas concentration in units of , The spatial second-order partial derivative of the gas concentration is used to describe the gas diffusion at the location coordinate.

[0041] S3. Collect real-time gas concentration information from sensors, calculate the gas concentration gradient and gas diffusion flux of each grid unit in the y direction based on the differential method and the gas concentration gradient, calculate the gas leakage of each grid unit, accumulate the gas leakage of each grid unit in real time, and calculate the total gas leakage of the power channel cross section.

[0042] In this embodiment, S3 includes the following specific steps: S31, calculating the gas concentration gradient and gas diffusion flux of each grid unit in the y direction based on the difference method and the gas concentration gradient; In this embodiment, since the gas diffusion is mainly along the y direction of the power channel, and the gas changes in the x and z directions in the power channel are small, the diffusion of the gas in the three-dimensional space is approximated as a one-dimensional diffusion model, and the gas leakage amount in the cross section of the power channel is obtained by calculating the gas concentration gradient in the y direction in each grid unit.

[0043] The gas concentration gradient of each grid cell in the y direction is calculated using the following formula:

[0044] In the formula, Represents the concentration gradient of each grid cell in the y direction, in units of , represents the gas concentration in the grid cell, Indicates the gas concentration outside the grid cell, Indicates the change in the y direction of the unit step of the grid cell.

[0045] The gas diffusion flux of each grid cell in the y direction is calculated using the following formula:

[0046] In the formula, Represents the gas diffusion flux of each grid unit in the y direction, in units of ,in , .

[0047] S32, calculating the gas leakage amount of each grid unit, accumulating the gas leakage amount of each grid unit in real time, and calculating the total gas leakage amount of the power channel cross section; The gas leakage of each grid unit is calculated using the following formula:

[0048] In the formula, Represents the gas leakage of each grid unit, where , .

[0049] Furthermore, the gas leakage of each grid unit is accumulated in real time, and the total gas leakage of the power channel section is calculated using the following formula:

[0050] In the formula, It represents the total amount of gas leakage in the cross section of the power channel. T represents the current time. The time when the gas initially leaks into the power channel is 0.

[0051] S4. Calculate the relative error based on the gas leakage and the actual leakage. If the relative error is less than 5%, output the current gas diffusion coefficient and gas leakage. If the relative error is greater than or equal to 5%, revise the gas diffusion coefficient, execute S3, and recalculate the gas leakage.

[0052] In this embodiment, the relative error is calculated using the following formula:

[0053] In the formula, Relative error, Indicates the actual leakage amount; in this embodiment, the actual leakage amount It is calculated through experimental testing and is a given leakage value.

[0054] In this embodiment, the fuel gas diffusion coefficient is revised using the following formula:

[0055] In the formula, represents the revised gas diffusion coefficient, Represents the adjustment factor used to control the revision rate.

[0056] The present invention utilizes the gas concentration information collected by the sensor array to monitor the gas diffusion behavior in the power channel. By arranging a multi-point sensor array in the cross section of the power channel, considering the influence of the obstacle characteristics in the power channel on the gas diffusion, the concentration distribution in the cross section of the power channel is calculated in combination with the gas diffusion law, and the monitoring model is improved through cyclic correction, so as to provide theoretical support for gas monitoring and early warning in the power channel, provide a scientific basis for accident prevention and handling, avoid the harm of gas leakage to the power system, and reduce the risk of gas explosion in the power channel.

[0057] Embodiment 2 The present invention also provides a gas diffusion monitoring system in an electric power channel based on a sensor array, comprising a sensor array arrangement module, a gas concentration analysis module, a gas diffusion state judgment module and a gas leakage error analysis module.

[0058] The sensor array arrangement module is used to divide the power channel into three-dimensional grids and divide the cross section of the power channel into The geometric dimensions of the power channel cross section are initialized, and the sensor array is arranged in each grid unit of the power channel cross section.

[0059] In this embodiment, the power channel is divided into three-dimensional grids, and the horizontal direction of the power channel cross section is defined as the x direction, the vertical direction of the power channel cross section is defined as the z direction, the extension direction of the power channel is defined as the y direction, and the plane where the power channel cross section is located is defined as the xoz plane. Each grid unit represents the gas concentration of a certain volume unit, and the area of ​​the cables and cable brackets is set as an obstacle area, and the gas cannot pass through.

[0060] In this embodiment, the cross section of the power channel is divided into The grid, represents the number of grids along the x direction, Indicates the number of grids along the z direction, initializes the geometric dimensions of the power channel section, sets the power channel section width to W, height to H, and the cross-sectional area of ​​each grid .

[0061] The power channel includes a cable trench, a power pipeline and a power well; a plurality of the cable trenches are connected in sequence, the power pipeline is laid in the cable trench, and both ends of the power well are connected to the cable trench; the cable trench is made of stainless steel, and the cable trenches are sealed by rubber rings or welding; mesh covers are provided at both ends of the power well, and the mesh covers are used to block and prevent interference from external airflow. The leakage point E is set at the bottom of the power channel, and the gas diffuses along the extension direction of the power channel through the leakage point E.

[0062] The sensor array is distributed in each grid unit of the power channel cross section, and each sensor can collect the gas concentration data of the grid unit where it is located in real time.

[0063] In this embodiment, n is set to 3, and the cross section of the power channel is divided into The sensor array includes an A-side sensor, a central sensor, and a B-side sensor arranged in sequence in the horizontal direction; the A-side sensor includes sensors A1, A2, and A3 arranged in sequence in the vertical direction; the central sensor includes sensors F1, F2, and F3 arranged in sequence in the vertical direction; and the B-side sensor includes sensors B1, B2, and B3 arranged in sequence in the horizontal direction. Based on the data collected by the sensor array, the concentration field of the entire cable trench can be constructed through numerical simulation to analyze the changes in gas concentration in the power channel.

[0064] The gas concentration analysis module is used for collecting real-time gas concentration information through sensors, calculating the gas diffusion coefficient in the power channel, and analyzing the change of gas concentration in the power channel using the gas diffusion equation.

[0065] In this embodiment, the expression of the gas diffusion coefficient is as follows:

[0066] In the formula, Indicates the gas diffusion coefficient of the current power channel cross section, in units of , the gas diffusion coefficient will be affected by obstacles (such as cables and cable racks), is the free diffusion coefficient, is the adjusted free diffusion coefficient, is the damping coefficient, take , represents the slowing effect of obstacles on gas diffusion, to simulate the hindering effect in the gas diffusion process. For example, near obstacles, the gas diffusion coefficient will decrease, while in open areas, the gas diffusion coefficient is the free diffusion coefficient value.

[0067] Since obstacles in different areas have different effects on gas diffusion, such as cables and brackets, which are common obstacles in power channels, they will block or slow down the diffusion of gas. By introducing the dynamic diffusion coefficient, that is, adjusting the diffusion coefficient according to the properties of obstacles in different positions, and using the dynamic diffusion coefficient to represent the impact of obstacles on diffusion, it can accurately reflect the actual situation of the gas diffusion process in the power channel, truly simulate the propagation characteristics of gas in the power channel, and improve the prediction ability and accuracy of the model.

[0068] At the same time, changes in the state of obstacles (such as cable movement, bracket removal) will lead to changes in environmental conditions. The present invention adjusts the diffusion coefficient according to the properties of obstacles at different locations, analyzes the gas diffusion under different environmental conditions, and improves the flexibility and adaptability of the analysis of gas concentration changes.

[0069] In this embodiment, the gas diffusion equation is used to simulate the gas diffusion process in the power channel, and is discretized in a three-dimensional grid space by a finite difference method. The expression of the gas diffusion equation is as follows:

[0070] In the formula, represents the internal time t and spatial position of the power channel The gas concentration in units of , The spatial second-order partial derivative of the gas concentration is used to describe the gas diffusion at the location coordinate.

[0071] The gas diffusion state judgment module is used to collect real-time gas concentration information according to the sensor, calculate the gas concentration gradient and gas diffusion flux of each grid unit in the y direction based on the difference method and the gas concentration gradient, calculate the gas leakage of each grid unit, accumulate the gas leakage of each grid unit in real time, and calculate the total gas leakage of the power channel cross section.

[0072] The gas diffusion state judgment module includes a grid leakage unit and a leakage total amount unit.

[0073] The grid leakage unit is used to calculate the gas concentration gradient and gas diffusion flux of each grid unit in the y direction based on the difference method and the gas concentration gradient; In this embodiment, since the gas diffusion is mainly along the y direction of the power channel, and the gas changes in the x and z directions in the power channel are small, the diffusion of the gas in the three-dimensional space is approximated as a one-dimensional diffusion model, and the gas leakage amount in the cross section of the power channel is obtained by calculating the gas concentration gradient in the y direction in each grid unit.

[0074] The gas concentration gradient of each grid cell in the y direction is calculated using the following formula:

[0075] In the formula, Represents the concentration gradient of each grid cell in the y direction, in units of , represents the gas concentration in the grid cell, Indicates the gas concentration outside the grid cell, Indicates the change in the y direction of the unit step of the grid cell.

[0076] The gas diffusion flux of each grid cell in the y direction is calculated using the following formula:

[0077] In the formula, Represents the gas diffusion flux of each grid cell in the y direction, in units of ,in , .

[0078] The total leakage amount unit is used to calculate the gas leakage amount of each grid unit, accumulate the gas leakage amount of each grid unit in real time, and calculate the total gas leakage amount of the power channel cross section; The gas leakage of each grid unit is calculated using the following formula:

[0079] In the formula, Represents the gas leakage of each grid unit, where , .

[0080] Furthermore, the gas leakage of each grid unit is accumulated in real time, and the total gas leakage of the power channel section is calculated using the following formula:

[0081] In the formula, It represents the total amount of gas leakage in the cross section of the power channel. T represents the current time. The time when the gas initially leaks into the power channel is 0.

[0082] The gas leakage error analysis module is used to calculate the relative error based on the gas leakage amount and the actual leakage amount. If the relative error is less than 5%, the current gas diffusion coefficient and gas leakage amount are output; if the relative error is greater than or equal to 5%, the gas diffusion coefficient is revised, the gas diffusion state judgment module is executed, and the gas leakage amount is recalculated.

[0083] In this embodiment, the relative error is calculated using the following formula:

[0084] In the formula, Relative error, Indicates the actual leakage amount; in this embodiment, the actual leakage amount It is calculated through experimental testing and is a given leakage value.

[0085] In this embodiment, the fuel gas diffusion coefficient is revised using the following formula:

[0086] In the formula, represents the revised gas diffusion coefficient, Represents the adjustment factor used to control the revision rate.

[0087] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for monitoring gas diffusion in a power channel based on a sensor array, characterized in that: The following steps are involved: S1. Divide the power channel into three-dimensional grids and divide the cross section of the power channel into The grid is used to initialize the geometric dimensions of the power channel cross section, and the sensor array is arranged in each grid unit of the power channel cross section, where: represents the number of grids along the x direction, Indicates the number of grids along the z direction; S2. The sensor collects real-time gas concentration information, calculates the gas diffusion coefficient in the power channel, and uses the gas diffusion equation to analyze the change of gas concentration in the power channel; S3. According to the real-time gas concentration information collected by the sensor, the gas concentration gradient and gas diffusion flux of each grid unit in the y direction are calculated based on the difference method and the gas concentration gradient, the gas leakage of each grid unit is calculated, the gas leakage of each grid unit is accumulated in real time, and the total gas leakage of the power channel cross section is calculated; S4. Calculate the relative error based on the gas leakage and the actual leakage. If the relative error is less than 5%, output the current gas diffusion coefficient and gas leakage. If the relative error is greater than or equal to 5%, revise the gas diffusion coefficient, execute S3, and recalculate the gas leakage.

2. The method for monitoring gas diffusion in a power channel based on a sensor array according to claim 1, characterized in that: In S2, the following formula is used to calculate the gas diffusion coefficient in the power channel: In the formula, Indicates the gas diffusion coefficient of the current power channel cross section, in units of , is the free diffusion coefficient, is the adjusted free diffusion coefficient, is the damping coefficient.

3. The method for monitoring gas diffusion in a power channel based on a sensor array according to claim 2, characterized in that: The expression of the gas diffusion equation in S2 is as follows: In the formula, represents the internal time t and spatial position of the power channel The gas concentration in units of , Represents the spatial second-order partial derivative of gas concentration.

4. The method for monitoring gas diffusion in a power channel based on a sensor array according to claim 3, characterized in that: In S3, the gas concentration gradient of each grid cell in the y direction is calculated using the following formula: In the formula, Represents the concentration gradient of each grid cell in the y direction, in units of , represents the gas concentration in the grid cell, Indicates the gas concentration outside the grid cell, Indicates the change in the y direction of the unit step of the grid cell.

5. The method for monitoring gas diffusion in a power channel based on a sensor array according to claim 4, characterized in that: In S3, the gas diffusion flux of each grid unit in the y direction is calculated using the following formula: In the formula, Represents the gas diffusion flux of each grid cell in the y direction, in units of ,in , .

6. The method for monitoring gas diffusion in a power channel based on a sensor array according to claim 5, characterized in that: In S3, the gas leakage amount of each grid unit is calculated using the following formula: In the formula, It represents the gas leakage of each grid unit, W represents the cross-sectional width of the power channel, and H represents the cross-sectional height of the power channel.

7. The method for monitoring gas diffusion in a power channel based on a sensor array according to claim 6, characterized in that: In S3, the total amount of gas leakage in the cross section of the power channel is calculated using the following formula: In the formula, It represents the total amount of gas leakage in the cross section of the power channel. T represents the current time. The time when the gas initially leaks into the power channel is 0.

8. The method for monitoring gas diffusion in a power channel based on a sensor array according to claim 7, characterized in that: The relative error is calculated using the following formula in S4: In the formula, Relative error, Indicates the total amount of power channel leakage, Indicates the actual leakage amount.

9. The method for monitoring gas diffusion in a power channel based on a sensor array according to claim 8, characterized in that: In S4, the following formula is used to revise the gas diffusion coefficient: In the formula, represents the revised gas diffusion coefficient, Represents the adjustment factor.

10. A gas diffusion monitoring system in a power channel based on a sensor array, characterized in that: It includes a sensor array arrangement module, a gas concentration analysis module, a gas diffusion state judgment module and a gas leakage error analysis module; The sensor array arrangement module is used to divide the power channel into three-dimensional grids and divide the cross section of the power channel into The grid is used to initialize the geometric dimensions of the power channel cross section, and the sensor array is arranged in each grid unit of the power channel cross section, where: represents the number of grids along the x direction, Indicates the number of grids along the z direction; The gas concentration analysis module is used for collecting real-time gas concentration information through sensors, calculating the gas diffusion coefficient in the power channel, and analyzing the gas concentration change in the power channel using the gas diffusion equation; The gas diffusion state judgment module is used to collect real-time gas concentration information according to the sensor, calculate the gas concentration gradient and gas diffusion flux of each grid unit in the y direction based on the difference method and the gas concentration gradient, calculate the gas leakage of each grid unit, accumulate the gas leakage of each grid unit in real time, and calculate the total gas leakage of the power channel cross section; The gas leakage error analysis module is used to calculate the relative error based on the gas leakage amount and the actual leakage amount. If the relative error is less than 5%, the current gas diffusion coefficient and gas leakage amount are output; if the relative error is greater than or equal to 5%, the gas diffusion coefficient is revised, the gas diffusion state judgment module is executed, and the gas leakage amount is recalculated.

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