Method, system and equipment for calculating diffusion distribution concentration of dissolved gas in transformer oil and medium

Abstract

The invention discloses a method, a system, equipment and a medium for calculating diffusion distribution concentration of dissolved gas in transformer oil, and relates to the technical field of state monitoring and fault diagnosis of power equipment, and the method comprises the following steps: establishing a three-dimensional dynamic transport model of the dissolved gas in the oil in a transformer, and setting initial release conditions of the three-dimensional dynamic transport model; setting a limited boundary condition of the three-dimensional dynamic transport model, solving the three-dimensional dynamic transport model through an integral transformation method to obtain a gas concentration distribution function under an instantaneous gas production source, and constructing three-dimensional gas concentration distribution under a continuous gas production state through time integration based on instantaneous gas production concentration distribution, and calculating the concentration of the dissolved gas in the oil by combining the motion parameters of the fluid in the transformer. According to the method, high-precision and high-efficiency calculation of the concentration distribution of the dissolved gas in the transformer oil is realized, the problem that a traditional method cannot give consideration to calculation speed and precision is solved, and a core technical support is provided for transformer fault real-time monitoring and digital twinning.

Description

Technical Field

[0001] This invention relates to the field of power equipment condition monitoring and fault diagnosis technology, specifically to a method, system, equipment, and medium for calculating the diffusion distribution concentration of dissolved gases in transformer oil. Background Technology

[0002] Dissolved gas analysis in transformer oil is an important means of assessing the insulation condition of transformers and diagnosing internal faults. When local overheating, discharge, or decomposition of insulation materials occurs inside a transformer, specific gases are generated and dissolved in the oil. By analyzing the composition and concentration of the gases, the type and severity of the fault can be determined. However, because the online monitoring points of oil chromatography are single and fixed, the concentration changes are difficult to reflect the occurrence and development process of faults with low gas production rates in transformer oil.

[0003] In recent years, numerical simulation of gas transport based on computational fluid dynamics has attracted much attention and has made initial progress. However, current simulations do not take into account the complexity of gas transport mechanisms in transformer oil and neglect the dissolution process and initial diffusion process of gas generated from the fault area. In addition, since the gas eigenvalues ​​required for simulation, such as mass transfer rate and diffusion coefficient, are mostly derived from molecular simulation calculations, experimental research is clearly insufficient, resulting in a large gap between the simulation calculation of gas transport processes in transformer oil and reality. Furthermore, existing simulation methods require too much time, usually several hours or even days, which cannot meet the requirements of real-time detection.

[0004] Therefore, it is urgent to conduct experimental research on the gas transport characteristics in the oil inside transformers, obtain the gas eigenvalues ​​required for simulation, establish a thermal-fluid coupling model of the two-phase gas transport in the oil inside transformers, and provide theoretical support for virtual sensing of the gas transport distribution in the oil inside transformers and for tracing and locating the gas generation location using DGA. Summary of the Invention

[0005] In view of the above-mentioned existing problems, the present invention provides a method, system, equipment and medium for calculating the diffusion distribution concentration of dissolved gases in transformer oil, in order to solve the problems in the prior art that ignore the dissolution process and initial diffusion process of gas generated from the fault area, the simulation calculation of gas transport process in transformer oil has a large gap with reality, and the calculation time is too long, which cannot meet the requirements of real-time detection.

[0006] To address the aforementioned technical issues, a method for calculating the diffusion distribution concentration of dissolved gases in transformer oil is proposed, including:

[0007] A three-dimensional dynamic transport model of dissolved gas in transformer oil is established, coupling the effects of oil flow motion and temperature field on gas transport, and setting the initial release conditions of the three-dimensional dynamic transport model. Finite boundary conditions of the three-dimensional dynamic transport model are set, and the model is solved by integral transformation method to obtain the gas concentration distribution function under instantaneous gas generation source. Based on the instantaneous gas generation concentration distribution, a three-dimensional gas concentration distribution under continuous gas generation state is constructed by time integration, and the concentration of dissolved gas in oil is calculated by combining the fluid motion parameters inside the transformer.

[0008] As a preferred embodiment of the method for calculating the concentration of dissolved gas diffusion distribution in transformer oil according to the present invention, the three-dimensional dynamic transport model includes coupling the influence of oil flow motion and temperature field on gas transport, and describing the dynamic distribution process of gas in oil based on unsteady diffusion mechanism and convection.

[0009] Constructing a three-dimensional dynamic transport model also includes determining the computational domain, namely the internal three-dimensional space of the transformer tank;

[0010] Define the dependent variable as the concentration of dissolved gases in the oil;

[0011] A diffusion coefficient term related to temperature and gas type is introduced to characterize molecular diffusion.

[0012] The transformer oil velocity field generated by the oil pump circulation and thermosiphon effect is introduced as a coefficient of the convection term to characterize the oil flow carrying effect.

[0013] As a preferred embodiment of the method for calculating the concentration of dissolved gas diffusion distribution in transformer oil according to the present invention, the initial release conditions of the three-dimensional dynamic transport model include setting the distribution state of gas in space at an initial moment in the three-dimensional dynamic transport model according to the fault location and the gas release intensity, and the initial value of the concentration in the remaining region is zero.

[0014] As a preferred embodiment of the method for calculating the concentration of dissolved gas diffusion distribution in transformer oil according to the present invention, the finite boundary conditions include treating the physical boundary of the transformer oil tank as an impenetrable wall, considering the actual structural limitations inside the transformer, and simulating the gas diffusion process in the confined space by setting the gas reflection behavior at the boundary.

[0015] As a preferred embodiment of the method for calculating the concentration of dissolved gas diffusion distribution in transformer oil according to the present invention, the integral transformation method includes performing a Fourier transform on both sides of the three-dimensional dynamic transport model, transforming the original partial differential equation containing partial derivatives into an ordinary differential equation containing only ordinary derivatives, and solving the ordinary differential equation to obtain an intermediate function solution in the transform domain with respect to the spatial frequency variable.

[0016] The integral transform formula is expressed as:

[0017]

[0018] Where i is the complex unit. The frequency domain function is obtained by performing a three-dimensional Fourier transform on the concentration function, where t is the diffusion time of dissolved gas transport in the oil, M is the mass of gas released instantaneously, and D... x D y and D z Let u be the diffusion coefficient of the dissolved gas in oil along the x, y, and z coordinate axes. x u y and u z Let ξ1, ξ2, and ξ3 be the oil flow velocity components in the x, y, and z coordinate axes of the transformer oil, ξ1, ξ2, and ξ3 be the frequency variables, and exp be the natural exponential function.

[0019] As a preferred embodiment of the method for calculating the diffusion distribution concentration of dissolved gases in transformer oil according to the present invention, the method for constructing the three-dimensional gas concentration distribution under continuous gas production includes: considering continuous gas production as a superposition of gas production sources from the initial time to the current time; integrating the instantaneous point source concentration distribution function from time zero to the current time; and obtaining the three-dimensional gas concentration distribution of the continuous gas production source at time t through integration, expressed by the formula:

[0020]

[0021] H1=2nh1

[0022] H2=2nh2

[0023] H3=2nh3

[0024] Where H1, H2, and H3 are the coordinates of the mirror source, h1, h2, and h3 are the half-dimensional dimensions of the tank boundary, and n is the number of reflections.

[0025] As a preferred embodiment of the method for calculating the concentration of dissolved gas diffusion distribution in transformer oil according to the present invention, the calculation of the concentration of dissolved gas in the oil includes: processing the oil flow velocity inside the transformer into a stable flow field that does not change with time and whose velocity component remains constant at each spatial point; using the velocity components in three directions to characterize the convective transport effect of the oil flow on gas transport; experimentally measuring the diffusion coefficient values ​​of specific gases in transformer oil at different temperatures to form data on the relationship between diffusion coefficient and temperature; obtaining data on the oil flow velocity field under normal operating conditions of the transformer; inputting the measured diffusion coefficient and specific oil flow velocity values; and calculating the concentration of dissolved gas diffusion distribution in the actual transformer.

[0026] The beneficial effects of this preferred technical solution are that simplifying the velocity field into a constant field is an excellent engineering balance between computational complexity and accuracy. It captures the main flow characteristics while greatly simplifying the calculation, and obtains key parameters through experiments, ensuring the reliability of the model input parameters. This means that the calculation results no longer depend on theoretical assumptions but have a solid experimental basis, thus providing double assurance for the accuracy of the output results.

[0027] As a preferred embodiment of the system for calculating the concentration of dissolved gas diffusion distribution in transformer oil according to the present invention, it is characterized by including a multi-physics coupling modeling module, a boundary reflection effect processing module, an analytical solution and transformation calculation module, and a continuous source superposition and concentration synthesis module.

[0028] The multiphysics coupling modeling module is used to simultaneously consider the combined effects of the transformer oil velocity field and temperature field on the gas transport process, couple the partial differential equations of convection effect and diffusion effect, and establish a three-dimensional dynamic mathematical model of dissolved gas transport in the transformer oil.

[0029] The boundary reflection effect processing module is used to transform physical boundary conditions into virtual mirror sources, and simulate the multiple reflection behavior of gas at the tank wall by infinite summation, thereby correcting the analytical solution under infinite space to a solution that conforms to the real sealed environment of the transformer.

[0030] The analytical solution and transformation calculation module is used to transform partial differential equations into ordinary differential equations through mathematical transformations for solution, and to obtain the analytical solution of instantaneous concentration distribution in the spatial domain through inverse transformation.

[0031] The continuous source superposition and concentration synthesis module is used to decompose continuous gas production faults into countless instantaneously released micro-sources based on the Duhamel principle, and to superimpose the concentration contribution of each instantaneous source through time integration, so as to provide quantitative basis for fault tracing and condition assessment.

[0032] A computer device includes a memory and a processor, the memory storing a computer program, the processor executing the computer program to implement the steps of a method for calculating the diffusion distribution concentration of dissolved gases in transformer oil.

[0033] A computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of a method for calculating the diffusion distribution concentration of dissolved gases in transformer oil.

[0034] The beneficial effects of this invention are as follows: By establishing a three-dimensional dynamic transport model that couples the effects of oil flow motion and temperature field, this invention achieves an accurate mathematical description of the diffusion process of dissolved gases in transformer oil, overcoming the limitations of traditional static models; by setting finite boundary conditions and using the integral transform method for solution, it innovatively obtains analytical solutions containing complex boundary conditions, significantly improving computational efficiency and accuracy; by treating continuous gas production as the superposition of instantaneous point sources and performing time integration, it constructs a three-dimensional gas concentration distribution under continuous gas production conditions, effectively solving the simulation problem of continuous gas production processes in actual working conditions; and by establishing a database of the relationship between diffusion coefficient and temperature and combining it with the assumption of a stable flow field, it combines experimental data with theoretical models, achieving high-precision concentration prediction at the engineering application level. Attached Figure Description

[0035] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 The above is a flowchart of the method for calculating the diffusion distribution concentration of dissolved gases in transformer oil according to an embodiment of the present invention.

[0037] Figure 2 The flowchart shows a system scheme for calculating the diffusion distribution concentration of dissolved gases in transformer oil, as provided in one embodiment of the present invention. Detailed Implementation

[0038] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0039] Example 1, referring to Figure 1 As an embodiment of the present invention, a method for calculating the diffusion distribution concentration of dissolved gases in transformer oil is provided, including:

[0040] S100: Establish a three-dimensional dynamic transport model of dissolved gas in the transformer oil, couple the influence of oil flow motion and temperature field on gas transport, and set the initial release conditions of the three-dimensional dynamic transport model.

[0041] S200: Set the finite boundary conditions for the three-dimensional dynamic transport model, and solve the three-dimensional dynamic transport model by the integral transform method to obtain the gas concentration distribution function under the instantaneous gas production source.

[0042] S300: Based on the instantaneous gas production concentration distribution, a three-dimensional gas concentration distribution under continuous gas production state is constructed through time integration, and the concentration of dissolved gas in oil is calculated by combining the fluid motion parameters inside the transformer.

[0043] It should be noted that the method for calculating the concentration of dissolved gas diffusion distribution in transformer oil of the present invention, by establishing a three-dimensional dynamic transport model that couples oil flow motion and temperature field and setting initial release conditions, for the first time uniformly considers the core mechanisms of convection and diffusion at the algorithm level, fundamentally improving the accuracy and reliability of concentration distribution calculation; by setting finite boundary conditions to simulate tank wall reflection and using integral transformation method for solution, the complex partial differential equation is transformed into an easily solvable form, significantly improving the calculation efficiency while ensuring accuracy, making high-precision real-time virtual sensing possible; by constructing a continuous gas production concentration distribution based on time integration of instantaneous solutions and combining it with experimentally measured fluid motion parameters for calculation, the practicality and engineering application value of the method are greatly enhanced, realizing accurate simulation and quantitative analysis of persistent faults.

[0044] Example 2, refer to Figure 1 This is a second embodiment of the present invention, which provides a method for calculating the concentration of dissolved gas diffusion distribution in transformer oil, including:

[0045] In step S100, the three-dimensional dynamic transport model includes coupling the effects of oil flow motion and temperature field on gas transport, and describing the dynamic distribution process of gas in oil based on unsteady diffusion mechanism and convection.

[0046] In this embodiment of the application, the construction of the three-dimensional dynamic transport model in step S100 further includes steps S101 to S104:

[0047] S101: Define the computational domain, i.e., the internal three-dimensional space of the transformer tank;

[0048] S102: Define the dependent variable as the concentration of dissolved gases in the oil;

[0049] S103: Introduces a diffusion coefficient term related to temperature and gas type to characterize molecular diffusion;

[0050] S104: Introducing the transformer oil velocity field generated by the oil pump circulation and thermosiphon effect as a coefficient of the convection term, characterizing the oil flow carrying effect, expressed by the formula:

[0051]

[0052] Where C(x,y,z,t) is the concentration of dissolved gas in the oil, x, y, and z are three-dimensional spatial coordinates, and D... x D y and D z Let u be the diffusion coefficient of the dissolved gas in oil along the x, y, and z coordinate axes. x u y and u z Let t represent the oil flow velocity components of the transformer oil in the x, y, and z coordinate axes, and t represent the diffusion time for the transport of dissolved gases in the oil.

[0053] In an optional implementation, in step S100, constructing the three-dimensional dynamic transport model further includes using numerical methods to perform approximate calculations, discretizing the three-dimensional space inside the transformer into a large number of small control volume grids, integrating the convection-diffusion partial differential equations on each control volume, transforming them into a system of algebraic equations about the concentration at the center of each grid cell, and solving the large system of equations by combining initial conditions and boundary conditions using an iterative algorithm (SIMPLE algorithm) to obtain the concentration distribution in the entire computational domain.

[0054] In another optional implementation, in step S100, constructing the three-dimensional dynamic transport model may further include: constructing a simplified model using machine learning methods; generating a large amount of concentration distribution sample data at different fault locations, gas production rates, and oil flow velocities using a high-fidelity convection-diffusion model or a finite volume method model; training a neural network proxy model using fault parameters and location coordinates as inputs and the current gas concentration as the output; and calling the trained neural network in the application phase, inputting the current state parameters, and quickly outputting the concentration distribution prediction value.

[0055] Furthermore, in step S100, setting the initial release conditions for the three-dimensional dynamic transport model includes steps S111 to S112:

[0056] S111: Based on the location of the fault and the intensity of gas release, set the initial spatial distribution of gas in the three-dimensional dynamic transport model;

[0057] S112: The initial concentration in the remaining region is zero, and the initial release condition is expressed as follows:

[0058] C(x,y,z,0)=Mδ(x)δ(y)δ(z)

[0059]

[0060] Where C(x,y,z,0) is the initial concentration distribution of dissolved gas in the oil, M is the mass of gas released instantaneously, δ(x) is the Dirac delta function with respect to variable x, δ(y) is the Dirac delta function with respect to variable y, δ(z) is the Dirac delta function with respect to variable z, and x0, y0 and z0 are the three-dimensional spatial coordinates of the fault source (gas production point).

[0061] In this embodiment of the application, in step S200, the finite boundary conditions include steps S201 to S204:

[0062] S201: Treat the physical boundary of the transformer tank as an impenetrable wall;

[0063] S202: To simulate the phenomenon that gas cannot continue to diffuse outward after diffusing to the wall and is reflected back into the tank, the "mirror method" principle is used.

[0064] S203: Virtually set up a series of mirror sources at the symmetrical positions of the actual fault sources with respect to each enclosure wall;

[0065] S204: The diffusion solutions of the original real source and all mirror sources in an infinite space are superimposed. The superposition result automatically satisfies the condition that the concentration flux is zero (i.e., the reflection boundary) at the boundary of the oil tank, which is equivalent to simulating diffusion in a finite space.

[0066] The boundary conditions are expressed as follows:

[0067]

[0068] Where C(x,y,z,t) is the concentration of dissolved gas in the oil, x, y and z are three-dimensional spatial coordinates, and t is the diffusion time for the transport of dissolved gas in the oil.

[0069] In an optional implementation, in step S200, the finite boundary condition further includes explicitly specifying that the concentration gradient in the boundary normal direction is zero on the boundary element of the discrete grid, which means that there is no net inflow or outflow of gas at the boundary, equivalent to a physically impenetrable boundary, and directly embedding the condition into the discrete equations of the finite volume method or finite element method for simultaneous solution.

[0070] In another optional implementation, in step S200, the finite boundary condition may further include defining the boundary condition as a linear combination of the concentration value at the boundary and its normal gradient (i.e., Robin boundary condition), and approximating the extremely weak adsorption effect of the box wall material on the gas by setting the absorption coefficient, but the main body still exhibits a blocking effect.

[0071] It should be noted that the "mirror method" used in the implementation of this application to process the reflection boundary transforms the complex finite domain boundary problem into a simple problem of multiple sources superimposed in an infinite domain. While maintaining the analytical solution form, it efficiently and accurately describes the diffusion behavior of gas in a closed oil tank, ensuring the physical reality of the model.

[0072] Furthermore, in step S200, the integral transformation method includes steps S211 to S214:

[0073] S211: Simultaneously perform a three-dimensional Fourier transform on both sides of the constructed three-dimensional convection-diffusion partial differential equation with respect to spatial coordinates.

[0074] S212: Using the differential properties of the Fourier transform, the spatial partial derivative terms in the equation are converted into algebraic terms in the frequency domain, and the original partial differential equation is transformed into an ordinary differential equation in time, expressed by the formula:

[0075]

[0076] Where i is the complex unit. The frequency domain function is obtained by performing a three-dimensional Fourier transform on the concentration function, where t is the diffusion time for dissolved gas transport in the oil, and D... x D y and D z Let u be the diffusion coefficient of the dissolved gas in oil along the x, y, and z coordinate axes. x u y and u z Let ξ1, ξ2, and ξ3 be the oil flow velocity components in the x, y, and z coordinate axes of the transformer oil, and let ξ1, ξ2, and ξ3 be the frequency variables.

[0077] S213: Solve the simplified ordinary differential equation to obtain the expression for the gas concentration in the frequency domain, which is expressed as:

[0078]

[0079] Where M is the mass of gas released instantaneously, i is a complex unit, t is the diffusion time of dissolved gas transport in oil, and exp is the natural exponential function.

[0080] S214: Perform a three-dimensional inverse Fourier transform on the frequency domain solution to restore it to the true spatial coordinate domain, obtaining the analytical solution of the spatial concentration distribution under the instantaneous point source, expressed by the formula:

[0081]

[0082] Where i is the complex unit. is the symbol for a triple integral, π is the mathematical constant pi, and exp is the natural exponential function.

[0083] In an optional implementation, in step S200, the integral transformation method further includes performing a Laplace transform on both sides of the three-dimensional convection-diffusion equation with respect to the time variable, converting the time partial derivative terms in the equation into algebraic terms in the complex frequency domain, thereby transforming the partial differential equation into an elliptic partial differential equation (Helmholtz equation) with respect to the spatial variable, and solving the spatial equation in combination with the boundary conditions to obtain the solution in the complex frequency domain, and applying the inverse Laplace transform (numerical inversion algorithm) to transform the solution back to the time domain to obtain the concentration distribution.

[0084] In another optional implementation, in step S200, the integral transformation method may further include substituting the assumed solution form into the original partial differential equation, separating the equation into ordinary differential equations containing only one independent variable through mathematical processing, and solving these ordinary differential equations in combination with boundary conditions to obtain a series of characteristic functions and eigenvalues. The general solution is a linear superposition of all characteristic functions. The superposition coefficient is determined through initial conditions, and finally an analytical solution is obtained.

[0085] In this embodiment of the application, step S300, the construction of the three-dimensional gas concentration distribution under continuous gas production state includes steps S301 to S303:

[0086] S301: Continuous gas production is considered as the superposition of gas production sources from the initial moment to the current moment;

[0087] S302: Integrate the instantaneous point source concentration distribution function from time zero to the current time.

[0088] S303: The three-dimensional gas concentration distribution of the continuous gas-producing source at time t is obtained by integration, expressed by the formula:

[0089]

[0090] It should be noted that the diffusion distance of dissolved gases in the transformer oil has boundaries, and when the gas is transported to one side of the tank wall, it is reflected and continues to diffuse until equilibrium is reached. Let the boundary distances of diffusion be -h1≤x≤h1, -h2≤y≤h2, and -h3≤z≤h3. Then the total diffusion distances in the x, y, and z directions are 2h1, 2h2, and 2h3, respectively. Adding the boundary conditions to the above equation, the concentration of dissolved gases in the oil can be expressed as:

[0091]

[0092] H1=2nh1

[0093] H2=2nh2

[0094] H3=2nh3

[0095] Where x, y, and z are three-dimensional spatial coordinates, π is pi, C(x,y,z,t) is the concentration of dissolved gas in the oil, H1, H2, and H3 are the coordinates of the mirror source position, h1, h2, and h3 are the half-dimensional dimensions of the oil tank boundary, n is the number of reflections, and M is the mass of gas released instantaneously.

[0096] In an optional implementation, in step S300, the construction of the three-dimensional gas concentration distribution under continuous gas production conditions further includes assuming that the gas production rate is constant and has been sustained for a long time, the concentration field no longer changes with time, and setting the time partial derivative term in the original partial differential equation to zero to obtain the steady-state convection-diffusion equation. The steady-state equation is then solved directly in combination with the boundary conditions to obtain the steady-state concentration distribution in space.

[0097] In another optional implementation, in step S300, constructing the three-dimensional gas concentration distribution under continuous gas production may further include discretizing the total time into multiple small time steps, calculating the concentration increment generated by gas production within the current step (considered as an instantaneous source) at each time step, and using the principle of linear superposition, superimposing the increment of the current time step with the concentration field generated in all previous time steps and diffused into the current state to obtain the transient concentration distribution under continuous gas production.

[0098] Furthermore, in step S300, the calculation of the concentration of dissolved gas in the oil includes processing the oil flow velocity inside the transformer into a stable flow field that does not change with time and whose velocity component remains constant at each spatial point. The velocity components in three directions are used to characterize the convective transport effect of the oil flow on gas transport. The diffusion coefficient values ​​of specific gases in transformer oil at different temperatures are measured experimentally to form data on the relationship between diffusion coefficient and temperature. Data on the oil flow velocity field under normal operating conditions of the transformer are also obtained. The measured diffusion coefficient and specific oil flow velocity values ​​are input to calculate the diffusion distribution concentration of dissolved gas in the actual transformer.

[0099] The formula for calculating the concentration of dissolved gases in oil is expressed as:

[0100]

[0101] Where dC(x,y,z,t) is the concentration element, and t s Let x be the transport time, and y and z be the three-dimensional spatial coordinates.

[0102] It should be noted that the concentration distribution formed by the transport of dissolved gas in the oil during continuous gas production from the fault source is composed of the superposition of these tiny unit concentration distributions. From time 0 to any time t, the diffusion distribution concentration solution at any location from the fault source can be expressed as:

[0103]

[0104] Among them, t s Let dτ be the transport time, and dτ be the time infinitesimal element.

[0105] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

[0106] Example 3, referring to Figure 2 This is the third embodiment of the present invention. This embodiment provides a system for calculating the concentration of dissolved gas diffusion distribution in transformer oil, including a multiphysics coupling modeling module, a boundary reflection effect processing module, an analytical solution and transformation calculation module, and a continuous source superposition and concentration synthesis module.

[0107] The multiphysics coupling modeling module is used to simultaneously consider the combined effects of the transformer oil velocity field and temperature field on the gas transport process, couple the partial differential equations of convection effect and diffusion effect, and establish a three-dimensional dynamic mathematical model of dissolved gas transport in the transformer oil.

[0108] The boundary reflection effect processing module is used to transform physical boundary conditions into virtual mirror sources, and simulate the multiple reflection behavior of gas at the tank wall by infinite summation, thereby correcting the analytical solution under infinite space to a solution that conforms to the real sealed environment of the transformer.

[0109] The analytical solution and transformation calculation module is used to transform partial differential equations into ordinary differential equations through mathematical transformations for solution, and to obtain the analytical solution of instantaneous concentration distribution in the spatial domain through inverse transformation.

[0110] The continuous source superposition and concentration synthesis module is used to decompose continuous gas production faults into countless instantaneously released micro-sources based on the Duhamel principle, and to superimpose the concentration contribution of each instantaneous source through time integration, so as to provide quantitative basis for fault tracing and condition assessment.

[0111] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

[0112] Example 4, the fourth embodiment of the present invention, differs from the previous three embodiments in that:

[0113] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0114] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device.

[0115] More specific examples of computer-readable media (a non-exhaustive list) include: electrical connections (electronic devices) having one or more wires, portable computer disk drives (magnetic devices), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Furthermore, computer-readable media can even be paper or other suitable media on which the program can be printed, because the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in computer memory.

[0116] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

Claims

1. A method for calculating the diffusion distribution concentration of dissolved gases in transformer oil, characterized in that: The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil.

2. The method of claim 1, wherein: The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil.

3. The method for calculating the concentration of dissolved gas diffusion distribution in transformer oil as described in claim 2, characterized in that: The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil.

4. The method of claim 3, wherein: The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil.

5. The method for calculating the concentration of dissolved gas diffusion distribution in transformer oil as described in claim 4, characterized in that: The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. where i is the imaginary unit, is the frequency domain function obtained by three-dimensional Fourier transform of the concentration function, t is the diffusion time of the dissolved gas transport in oil, M is the instantaneous released gas mass, D x , D y , and D z are the diffusion coefficients of the dissolved gas in oil along the x, y, z coordinate axes, u x , u y , and u z are the oil flow velocity components of the transformer oil along the x, y, z coordinate axes, ξ1, ξ2, and ξ3 are the frequency variables, and exp is the natural exponential function.

6. The method of claim 5, wherein: ###0002### The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil.

7. The method for calculating the concentration of dissolved gas diffusion distribution in transformer oil as described in claim 6, characterized in that: The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic transport model of dissolved gas in transformer oil. The application relates to a three-dimensional dynamic 8. A system for calculating diffusion distribution concentrations of dissolved gases in transformer oil, which applies the method for calculating diffusion distribution concentrations of dissolved gases in transformer oil according to any one of claims 1 to 7, characterized by, It includes a multiphysics coupling modeling module, a boundary reflection effect processing module, an analytical solution and transformation calculation module, and a continuous source superposition and concentration synthesis module; The multiphysics coupling modeling module is used to simultaneously consider the combined effects of transformer oil velocity field and temperature field on the gas transport process, couple the partial differential equations of convection effect and diffusion effect, and establish a three-dimensional dynamic mathematical model of dissolved gas transport in transformer oil. The boundary reflection effect processing module is used to transform physical boundary conditions into virtual mirror sources, and simulate the multiple reflection behavior of gas at the tank wall by infinite summation, so as to correct the analytical solution under infinite space to a solution that conforms to the real closed environment of transformer. The analytical solution and transformation calculation module is used to transform partial differential equations into ordinary differential equations through mathematical transformations for solution, and to obtain the analytical solution of instantaneous concentration distribution in the spatial domain through inverse transformation; The continuous source superposition and concentration synthesis module is used to decompose continuous gas production faults into countless instantaneously released micro-sources based on the Duhamel principle, and to superimpose the concentration contribution of each instantaneous source through time integration, so as to provide quantitative basis for fault tracing and condition assessment. 9.A computer device, comprising a memory and a processor, wherein the memory stores a computer program, and the computer device is configured to perform the method according to any one of claims 1-8 when the computer program is executed by the processor. When the processor executes the computer program, it implements the steps of the method for calculating the diffusion distribution concentration of dissolved gases in transformer oil as described in any one of claims 1 to 7.

10. A computer-readable storage medium having stored thereon a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the method for calculating the diffusion distribution concentration of dissolved gases in transformer oil as described in any one of claims 1 to 7.

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