Method and system for calculating arcing bubble temperature in transformer oil, medium and equipment

Abstract

The invention discloses a method, system, medium and equipment for calculating the average temperature of arcing bubbles in transformer oil, and the method comprises the steps: obtaining a time-varying curve V (t) of the bubble volume of the arcing bubbles in the transformer oil; the pressure intensity P (t) in the bubbles is calculated, and the static pressure stage is the liquid pressure intensity; establishing a mapping relation between the arc energy and the gas production rate n (t) through an experiment, and reversely deducing a gas production rate curve according to an arc energy curve after discharging is finished; and substituting the bubble volume V (t), the pressure P (t) and the gas production rate n (t) into an ideal gas state equation PV = nRT, and solving the time-varying process of the average temperature of the bubbles to obtain the average temperature of the arcing bubbles in the transformer oil. And based on the pressure-temperature relationship at the discharge ending moment, assuming that the pressure drop is caused by temperature change and the internal pressure of the tank body is equal everywhere, and calculating the average bubble temperature at the arcing ending moment by combining the volume change relationship of the oil tank.

Description

Technical Field

[0001] The present invention relates to the technical field of power equipment status monitoring, and in particular to a method, system, medium and equipment for calculating the average temperature of arc bubbles in transformer oil. Background Art

[0002] In high-voltage power equipment such as transformers, arc discharges in oil vaporize and crack the insulating oil, forming high-temperature, high-pressure bubbles around the arc. This increases internal tank pressure, potentially damaging the tank and causing a fire. The average temperature of the arcing bubbles is a key parameter in understanding the arc discharge evolution mechanism. Obtaining the time-varying average bubble temperature is crucial for understanding the arc discharge evolution and calculating pressure. However, because the internal temperature of the bubbles reaches 2000K, direct measurement of the bubble temperature is difficult with existing technology.

[0003] Arc discharges in the insulating oil of oil-immersed power equipment can have serious consequences. The high temperatures generated by the arc discharge (which can reach over 2000K) cause the insulating oil to undergo a violent vaporization and cracking reaction, forming high-temperature, high-pressure bubbles around the arc. The volume expansion of these bubbles significantly increases the pressure inside the oil tank. If the pressure exceeds the equipment's load capacity, it can cause the tank to rupture or even cause an explosion, posing a significant threat to equipment safety and power grid stability.

[0004] The average temperature of the arcing bubble is a key parameter in characterizing the evolution of arc discharge. Its dynamic variation not only directly influences the evolution of bubble volume and pressure but is also closely related to key factors such as the thermal decomposition characteristics of the insulating oil and the rate of gas product generation. Obtaining a time-varying curve of the average bubble temperature is crucial for understanding the physical mechanisms of arc discharge, predicting tank pressure evolution trends, and developing fault protection strategies.

[0005] However, existing technologies struggle to directly measure the internal temperature of bubbles. Traditional contact temperature measurement methods (such as thermocouples) are unable to penetrate insulating oil layers and are susceptible to interference from high-temperature and high-pressure environments, rendering them ineffective. Furthermore, non-contact measurement techniques (such as infrared imaging and spectroscopy) are limited by the dynamic characteristics of bubbles (rapid expansion and contraction) and optical path obstructions, making it difficult to provide temperature data with high temporal and spatial resolution.

[0006] The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Summary of the Invention

[0007] The present invention provides a method, system, medium and equipment for calculating the average temperature of arc bubbles in transformer oil. The method reversely infers the internal temperature of the bubbles through the ideal gas state equation, verifies the accuracy of the temperature calculation through two independent methods, and obtains the variation characteristics, thereby solving the problem of difficult measurement of arc temperature in oil.

[0008] A method for calculating the average temperature of arc bubbles in transformer oil includes:

[0009] Obtain the time-varying curve V(t) of the bubble volume of arcing bubbles in transformer oil;

[0010] Calculate the pressure inside the bubble, P(t), which includes the liquid pressure during the static pressure phase.

[0011] The mapping relationship between arc energy and gas production n(t) is established through experiments, and the gas production curve is inferred based on the arc energy curve after the discharge ends.

[0012] Substitute the bubble volume V(t), pressure P(t) and gas production n(t) into the ideal gas state equation PV=nRT, and solve the time-varying process of the bubble average temperature to obtain the average temperature of the arcing bubbles in the transformer oil. R is the ideal gas constant.

[0013] In the method for calculating the average temperature of arcing bubbles in transformer oil, calculating the average temperature of the bubbles at the end of arcing includes:

[0014] e1, the pressure drop at the end of discharge is caused by the temperature drop and the pressure inside the tank is equal everywhere;

[0015] e2, record the pressure P at the end of discharge end and steady-state pressure P steady , and the reserved gas volume V0, calculate the average bubble temperature at the end of arcing

[0016] C is the expansion coefficient of the fuel tank,

[0017] e3, repeat step e2 by changing the arcing time, and calculate the corresponding T for each arcing time. end , generate discrete points where the average bubble temperature changes with time, and fit the discrete points into the time-varying curve of the average bubble temperature through interpolation algorithm.

[0018] In the method for calculating the average temperature of arcing bubbles in transformer oil, the time-varying process of the average temperature of the bubbles is compared with the time-varying curve to correct the average temperature of the arcing bubbles in the transformer oil.

[0019] In the method for calculating the average temperature of arcing bubbles in transformer oil, the time-varying process of the average temperature of the bubbles is compared with the temperature T at the end of the arcing of the time-varying curve. endThe relative error is weighted by average to obtain the average temperature of the arc bubbles in the transformer oil.

[0020] In the method for calculating the average temperature of arcing bubbles in transformer oil, a time-varying curve of the bubble volume of arcing bubbles in transformer oil is obtained by using the adiabatic state equation of the top reserved gas, which includes:

[0021] a1. Install a pressure sensor in the reserved gas area at the top of the transformer oil tank to record the pressure-time curve P(t) of the top gas during the discharge process;

[0022] a2. According to the adiabatic process formula P(t)V(t) γ = constant, where γ is the adiabatic exponent. Combined with the initial volume V0 and the initial pressure P0, the bubble volume V(t) at any time is calculated.

[0023] In the method for calculating the average temperature of arcing bubbles in transformer oil, a time-varying curve of the bubble volume of the arcing bubbles in the transformer oil is obtained by a high-speed camera method. The method includes: using a high-speed camera to shoot the movement process of the arcing bubbles in the oil to obtain the change process of the bubble diameter; the bubbles are spherical, and the bubble volume V(t) is calculated using a spherical volume calculation formula.

[0024] In the method for calculating the average temperature of arc bubbles in transformer oil, gas production under different arc energies is simulated experimentally to establish a mapping relationship between arc energy E and gas production rate k, k(E)=aE+b, where a and b are fitting coefficients; the least squares method is used to fit the experimental data to obtain parameters a and b, thereby calculating the amount of gas-producing substances n(t)=k(E)*E(t) / 22400 based on the arc energy curve E(t) of the actual discharge process.

[0025] A system for implementing the method includes:

[0026] An acquisition module, which is used to obtain a time-varying curve V(t) of the bubble volume of arcing bubbles in transformer oil;

[0027] The pressure module is used to calculate the pressure P(t) inside the bubble, which includes the liquid pressure in the static pressure stage;

[0028] The gas production module establishes the mapping relationship between arc energy and gas production n(t) through experiments, and reversely infers the gas production curve based on the arc energy curve after the discharge ends;

[0029] The calculation module substitutes the bubble volume V(t), pressure P(t) and gas production n(t) into the ideal gas state equation PV=nRT, and solves the time-varying process of the bubble average temperature to obtain the average temperature of the arcing bubbles in the transformer oil.

[0030] A computer storage medium includes computer instructions, which, when executed on a computer, cause the computer to execute the method described above.

[0031] An electronic device, comprising:

[0032] A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein:

[0033] When the processor executes the program, the method described is implemented.

[0034] Compared with the prior art, the present invention has the following advantages: High-precision dynamic calculation of the present invention: By fusing the ideal gas state equation with experimental data, the dynamic calculation of the bubble temperature is realized. The second method does not require high-speed camera equipment, only pressure sensors and gas production data, which significantly reduces hardware costs. Reliability verification: The comparative verification of the results of the two methods can eliminate model assumption errors and improve the credibility of the calculation results. The present invention is more suitable for working conditions where the fuel tank is fully filled, simplifies experimental means, enhances feasibility, establishes a dual-method mutual verification mechanism, improves the credibility of the calculation results, and uses a calculation method to reversely infer the average temperature of the arc gas based on the pressure time-varying curve (measured by a pressure sensor) and the arc gas production rate (obtained from a large number of experiments). These two methods, starting from the perspectives of the thermodynamic pressure change mechanism and the dynamic evolution of the gas production rate, can be compared and verified with each other, thereby enhancing the reliability and scientificity of the temperature calculation results. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Various other advantages and benefits of the present invention will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiments below. The accompanying drawings are intended only to illustrate preferred embodiments and are not to be construed as limiting the present invention. It should be understood that the drawings described below are merely examples of the present invention, and that those skilled in the art will be able to derive other drawings from these drawings without inventive effort. Throughout the drawings, identical reference numerals are used to denote identical components.

[0036] In the attached figure:

[0037] Figure 1 This is a flow chart of a method for calculating the average temperature of arc discharge products in a transformer tank;

[0038] Figure 2 It is a scatter plot of the corresponding relationship between energy and gas production rate under different experimental conditions;

[0039] Figure 3 This is a schematic diagram of the change in average temperature of arc discharge bubbles under two calculation methods.

[0040] The present invention will be further explained below with reference to the accompanying drawings and embodiments. DETAILED DESCRIPTION

[0041] Specific embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although specific embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0042] It should be noted that certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that technicians may use different nouns to refer to the same component. This specification and claims do not use the difference in nouns as a way to distinguish components, but use the difference in the functions of the components as the criterion for distinction. As mentioned throughout the specification and claims, "including" or "comprising" is an open term, so it should be interpreted as "including but not limited to". The subsequent description of the specification is a preferred embodiment of the present invention, but the description is based on the general principles of the specification and is not intended to limit the scope of the invention. The scope of protection of the present invention shall be as defined in the attached claims.

[0043] To facilitate understanding of the embodiments of the present invention, further explanation will be given below using specific embodiments as examples in conjunction with the accompanying drawings, and the accompanying drawings do not constitute a limitation on the embodiments of the present invention.

[0044] like Figures 1 to 3 As shown in FIG, the method for calculating the average temperature of arc bubbles in transformer oil includes the following steps:

[0045] Obtain the time-varying curve V(t) of the bubble volume of arcing bubbles in transformer oil;

[0046] Calculate the pressure P(t) inside the bubble. The pressure inside the bubble in the static pressure stage is the same as the liquid pressure.

[0047] Through experiments, a mapping relationship between arc energy and gas production n(t) was established. The gas production curve was inferred from the arc energy curve after the discharge. Furthermore, an RLC circuit was constructed and arc discharge experiments were conducted within a sealed transformer oil tank at a current frequency of 50 Hz. The arc discharge voltage, current, and pressure waveforms were measured, as well as the arc gas production volume and the corresponding tank pressure at room temperature and pressure. Rogowski coils and high-voltage differential probes were used to measure the discharge current and voltage. A pressure sensor and a gas / liquid dual-purpose pressure gauge were used to measure the dynamic pressure waveform generated by the discharge and the steady-state pressure after the discharge. Arc discharge experiments were conducted under various conditions, such as varying arc lengths, current peaks, and reserved gas volumes. Arc energy was calculated based on the measured arc discharge voltage and current waveforms. Since the relationship between the discharge gas production rate (mL / kJ) and the arc energy (kJ) is linearly fitted, the gas production can be calculated from the arc energy.

[0048] Substitute the bubble volume V(t), pressure P(t), and gas production n(t) into the ideal gas state equation PV = nRT and solve for the time-varying average bubble temperature to obtain the average temperature of the arcing bubbles in the transformer oil. R is the ideal gas constant, which can be 8.314 J / (mol*K).

[0049] In a preferred embodiment of the method for calculating the average temperature of arcing bubbles in transformer oil, calculating the average temperature of the bubbles at the end of arcing includes:

[0050] e1, the pressure drop at the end of discharge is caused by the temperature drop and the pressure inside the tank is equal everywhere;

[0051] e2, record the pressure P at the end of discharge end and steady-state pressure P steady , and the reserved gas volume V0, calculate the average bubble temperature at the end of arcing

[0052] C is the expansion coefficient of the fuel tank,

[0053] e3, repeat step e2 by changing the arcing time, and calculate the corresponding T for each arcing time. end , generate discrete points where the average bubble temperature changes with time, and fit the discrete points into the time-varying curve of the average bubble temperature through interpolation algorithm.

[0054] In a preferred embodiment of the method for calculating the average temperature of arcing bubbles in transformer oil, the time-varying process of the average temperature of the bubbles is compared with the time-varying curve to correct the average temperature of the arcing bubbles in the transformer oil.

[0055] In a preferred embodiment of the method for calculating the average temperature of arc bubbles in transformer oil, the time-varying process of the average temperature of the bubbles is compared with the temperature T at the end of the arcing of the time-varying curve. end The relative error is weighted by average to obtain the average temperature of the arc bubbles in the transformer oil.

[0056] In a preferred embodiment of the method for calculating the average temperature of arcing bubbles in transformer oil, a time-varying curve of the bubble volume of arcing bubbles in transformer oil is obtained by using the adiabatic state equation of the top reserved gas, which includes:

[0057] a1. Install a pressure sensor in the reserved gas area at the top of the transformer oil tank to record the pressure-time curve P(t) of the top gas during the discharge process;

[0058] a2. According to the adiabatic process formula P(t)V(t) γ = constant, where γ is the adiabatic exponent. Combined with the initial volume V0 and the initial pressure P0, the bubble volume V(t) at any time is calculated.

[0059] In a preferred embodiment of the method for calculating the average temperature of arcing bubbles in transformer oil, a time-varying curve of the bubble volume of the arcing bubbles in the transformer oil is obtained by high-speed photography, which includes: using a high-speed camera to shoot the movement process of the arcing bubbles in the oil to obtain the change process of the bubble diameter; the bubbles are spherical, and the bubble volume V(t) is calculated using a spherical volume calculation formula.

[0060] In a preferred embodiment of the method for calculating the average temperature of arc bubbles in transformer oil, the gas production under different arc energies is simulated experimentally to establish a mapping relationship k(E)=aE+b between arc energy E (unit: kJ) and gas production rate k (unit: mL / kJ), where a and b are fitting coefficients; the least squares method is used to fit the experimental data to obtain parameters a and b, thereby calculating the amount of gas-producing substance n(t)=k(E)*E(t) / 22400 based on the arc energy curve E(t) of the actual discharge process.

[0061] A system for implementing the method includes:

[0062] An acquisition module, which is used to obtain a time-varying curve V(t) of the bubble volume of arcing bubbles in transformer oil;

[0063] The pressure module is used to calculate the pressure P(t) inside the bubble, which includes the liquid pressure in the static pressure stage;

[0064] The gas production module establishes the mapping relationship between arc energy and gas production n(t) through experiments, and reversely infers the gas production curve based on the arc energy curve after the discharge ends;

[0065] The calculation module substitutes the bubble volume V(t), pressure P(t) and gas production n(t) into the ideal gas state equation PV=nRT, and solves the time-varying process of the bubble average temperature to obtain the average temperature of the arcing bubbles in the transformer oil.

[0066] A computer storage medium includes computer instructions, which, when executed on a computer, cause the computer to execute the method described above.

[0067] An electronic device, comprising:

[0068] A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein:

[0069] When the processor executes the program, the method described is implemented.

[0070] In one embodiment, the bubble volume is calculated by inverting the arc bubble volume in the oil through the adiabatic state equation of the top reserved gas. According to the pressure-time curve of the top gas, combined with the adiabatic process formula PV γ = constant (where γ is the adiabatic exponent), calculate the change of bubble volume with time.

[0071] In one embodiment, the bubble volume is calculated by photographing the movement of arcing bubbles in the oil with a high-speed camera and extracting the time-varying curve of the bubble volume using image processing technology (such as edge detection algorithm).

[0072] Calculate the internal pressure of the bubble during the static pressure phase: The internal pressure of the bubble is equal to the pressure in the liquid. Calculate the amount of gas by experimentally establishing a mapping between arc energy and gas production. The arc energy curve after the discharge is used to infer the temporal evolution of the gas production. Calculate the average bubble temperature by substituting the aforementioned bubble volume, pressure, and gas production into the ideal gas state equation (PV = nRT) and solving for the time-varying average bubble temperature.

[0073] In one embodiment, the discharge end time is verified, and the pressure drop at the discharge end time is caused by the temperature drop; at the discharge end time, the pressure inside the tank is equal everywhere. Record the pressure P at the discharge end time end and steady-state pressure P steady ;

[0074] Combine the gas production data and the ideal gas state equation to calculate the average bubble temperature T at the end of arcing end By changing the arcing time (at intervals of 2ms), repeating the above calculations, a time-varying curve of the average bubble temperature is generated and compared and verified.

[0075] In one embodiment, step 1: bubble volume calculation

[0076] A pressure sensor is installed in the reserved gas area on the top of the transformer oil tank to record the pressure-time curve P(t) of the top gas during the discharge process.

[0077] According to the adiabatic process formula P(t)V(t) γ = constant, and the bubble volume V(t) at any moment is calculated by combining the initial volume V0 and the initial pressure P0.

[0078] Alternatively, a high-speed camera (frame rate ≥ 10,000 fps) is used to capture the motion of arcing bubbles in the oil to obtain the change in bubble diameter.

[0079] Assuming that the bubble is spherical, the bubble volume V(t) is calculated using the spherical volume calculation formula.

[0080] Step 2: Calculation of the internal pressure of the bubble

[0081] Static pressure stage:

[0082] The pressure inside the bubble P bubble =P oil , where P oil It is the liquid pressure, which can be measured by a pressure sensor in the liquid.

[0083] Step 3: Calculation of the amount of gaseous substance

[0084] Experimental data modeling:

[0085] By simulating the gas production under different arc energies in the laboratory, the mapping relationship n(E) between arc energy E and gas production n is established, such as Figure 2 shown.

[0086] The experimental data were fitted using the least squares method to obtain n(E)=aE+b (where a and b are fitting coefficients).

[0087] Gas production reverse calculation:

[0088] According to the arc energy curve E(t) of the actual discharge process, the amount of gas-generating substances n(t)=aE(t)+b is calculated.

[0089] Step 4: Calculation of average bubble temperature

[0090] Substituting into the ideal gas equation:

[0091] Substitute P(t), V(t), and n(t) into PV=nRT to solve for the average bubble temperature T(t)=n(t)RP(t)V(t). The calculation results are as follows: Figure 3 As shown in the figure, the bubble temperature rises to 5000K within 2ms and then drops rapidly to about 700K within 2-10ms and remains until the end of discharge.

[0092] Record the pressure P at the end of discharge end and steady-state pressure P steady , and the reserved gas volume V0, calculate the average bubble temperature at the end of arcing

[0093]

[0094] By changing the arcing time (in 2ms intervals), T end The time-varying curves of θ are compared with those of method 1.

[0095] like Figure 3 The calculation results shown here demonstrate the evolution of the average bubble temperature using both methods. Both methods exhibit a trend of rapid initial rise followed by a decrease. The temperature trends for both methods are identical, fluctuating around 700K at the final moment. Because Method 2 is based on experimental results and subject to experimental randomness, there are numerical deviations between the two methods. However, the temperature trends obtained by both methods are identical, and the calculated temperature values ​​are of the same order of magnitude.

[0096] This method reserves a gas space at the top of the transformer oil tank and records the pressure-time curve P(t). Using the formula: P(t)V(t)^γ = constant (γ is the specific heat ratio), the bubble volume V(t) at any given moment can be inferred from the known initial volume V0 and initial pressure P0. Non-invasive measurement: The bubble volume evolution process can be obtained without directly observing the bubble morphology, making it suitable for the internal environment of a sealed oil tank. Dynamic tracking: Suitable for capturing rapid changes in bubble volume during transient high-voltage discharge. Physical consistency assurance: A model established by the first law of thermodynamics ensures the scientific nature and continuity of volume data.

[0097] Bubble volume calculation based on high-speed video processing uses a high-speed camera (frame rate ≥ 10,000 fps) to capture the arc-induced bubble motion. Image processing algorithms extract the bubble edges and measure the bubble diameter, assuming a spherical structure. V(t) is calculated using the spherical volume formula. Intuitive visual verification provides realistic visual information about the bubble's dynamic behavior, useful for verifying other modeling methods.

[0098] Bubble pressure modeling: Static pressure stage: The internal pressure of the bubble is assumed to be equal to the external liquid pressure Poil, reducing experimental dependence: some parameters can be replaced by direct measurement through theoretical modeling; supporting bubble stability analysis: providing basic data for subsequent research on issues such as bubble rupture, resonance, and collapse.

[0099] The relationship between arc energy and gas production (k(E) = aE + b) was modeled. Discharge experiments with various arc energies were conducted in the laboratory, and gas production was measured. Least squares regression was used to fit the linear relationship k(E) = aE + b. The E(t) curve from the actual discharge process was substituted into the equation to obtain n(t). This enabled quantitative prediction of gas production, providing a quantitative basis for bubble generation rate and volume growth trends. Key input variables were constructed, providing the necessary n(t) data for temperature calculations.

[0100] Based on the temperature solution of the ideal gas state equation (PV=nRT), V(t), P(t), and n(t) are integrated and substituted into the ideal gas state equation to solve T(t) in real time. T based on steady-state pressure and expansion coefficient end Correct the calculation and use the steady-state pressure P after the discharge is completed steady and the pressure P at the end end ; Introduce the fuel tank gas expansion coefficient C and the reserved gas volume V0; derive the formula to calculate the final temperature T end . Improve model robustness: avoid errors that may be caused by relying solely on the ideal gas equation; support cross-validation of results: repeat the experiment by changing the arcing time, construct discrete points and interpolate to obtain a more accurate T(t) curve; enhance practicality: be applicable to actual engineering scenarios with different discharge types (short time / long time) and different tank sizes. Analyze relative errors and optimize the final temperature curve using weighted average. Improve calculation accuracy: comprehensively utilize the advantages of different methods to reduce errors caused by single-source uncertainty; enhance model adaptability: be applicable to different experimental conditions and equipment structures; provide a basis for standard setting: lay the foundation for the formation of standardized testing processes in the future.

[0101] Although the embodiments of the present invention have been described above with reference to the accompanying drawings, the present invention is not limited to the above-mentioned specific embodiments and application fields. The above-mentioned specific embodiments are merely illustrative and instructive, and are not restrictive. A person skilled in the art, guided by this specification and without departing from the scope of protection of the claims of the present invention, may also devise various forms, all of which fall within the scope of protection of the present invention.

Claims

1. A method for calculating the average temperature of arc bubbles in transformer oil, characterized in that: The steps include: a. Obtain the time-varying curve V(t) of the bubble volume of arc bubbles in transformer oil; b. Calculate the pressure inside the bubble, P(t), which includes the liquid pressure during the static pressure phase. c. Establish the mapping relationship between arc energy and gas production n(t) through experiments, and infer the gas production curve based on the arc energy curve after the discharge ends; d. Substitute the bubble volume V(t), pressure P(t), and gas production n(t) into the ideal gas state equation PV = nRT and solve the time-varying process of the average bubble temperature to obtain the average temperature of the arcing bubbles in the transformer oil. R is the ideal gas constant.

2. The method for calculating the average temperature of arc bubbles in transformer oil according to claim 1, wherein: Preferably, calculating the average bubble temperature at the end of arcing includes: e1, the pressure drop at the end of discharge is caused by the temperature drop and the pressure inside the tank is equal everywhere; e2, record the pressure P at the end of discharge end and steady-state pressure P steady , and the reserved gas volume V0, calculate the average bubble temperature at the end of arcing C is the expansion coefficient of the fuel tank, e3, repeat step e2 by changing the arcing time, and calculate the corresponding T for each arcing time. end , generate discrete points where the average bubble temperature changes with time, and fit the discrete points into the time-varying curve of the average bubble temperature through interpolation algorithm.

3. The method for calculating the average temperature of arc bubbles in transformer oil according to claim 2, wherein: The time-varying process of the average bubble temperature is compared with the time-varying curve to correct the average temperature of the arcing bubbles in the transformer oil.

4. The method for calculating the average temperature of arc bubbles in transformer oil according to claim 3, wherein: Compare the time-varying process of the average bubble temperature and the temperature T at the end of arcing of the time-varying curve end The relative error is weighted by average to obtain the average temperature of the arc bubbles in the transformer oil.

5. The method for calculating the average temperature of arc bubbles in transformer oil according to claim 1, wherein: The time-varying curve of the bubble volume of the arcing bubble in the transformer oil is obtained by the adiabatic state equation of the top reserved gas, which includes: a1. Install a pressure sensor in the reserved gas area at the top of the transformer oil tank to record the pressure-time curve P(t) of the top gas during the discharge process; a2. According to the adiabatic process formula P(t)V(t) γ = constant, where γ is the adiabatic exponent. Combined with the initial volume V0 and the initial pressure P0, the bubble volume V(t) at any time is calculated.

6. The method for calculating the average temperature of arc bubbles in transformer oil according to claim 1, wherein: The time-varying curve of the bubble volume of arcing bubbles in transformer oil is obtained by high-speed photography, which includes: using a high-speed camera to shoot the movement process of the arcing bubbles in the oil to obtain the change process of the bubble diameter; the bubbles are spherical, and the bubble volume V(t) is calculated using the spherical volume calculation formula.

7. The method for calculating the average temperature of arc bubbles in transformer oil according to claim 1, wherein: By experimentally simulating the gas production under different arc energies, a mapping relationship between arc energy E and gas production rate k is established: k(E)=aE+b, where a and b are fitting coefficients. The least squares method is used to fit the experimental data to obtain parameters a and b, and then the amount of gas-producing substances n(t)=k(E)*E(t) / 22400 is calculated based on the arc energy curve E(t) of the actual discharge process.

8. A system for implementing the method according to any one of claims 1 to 7, characterized in that: It includes: An acquisition module, which is used to obtain a time-varying curve V(t) of the bubble volume of arcing bubbles in transformer oil; The pressure module is used to calculate the pressure P(t) inside the bubble, which includes the liquid pressure in the static pressure stage; The gas production module establishes the mapping relationship between arc energy and gas production n(t) through experiments, and reversely infers the gas production curve based on the arc energy curve after the discharge ends; The calculation module substitutes the bubble volume V(t), pressure P(t) and gas production n(t) into the ideal gas state equation PV=nRT, and solves the time-varying process of the bubble average temperature to obtain the average temperature of the arcing bubbles in the transformer oil.

9. A computer storage medium, characterized in that The storage medium includes computer instructions, which, when executed on a computer, enable the computer to perform the method according to any one of claims 1 to 7.

10. An electronic device, characterized in that: The electronic device comprises: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method according to any one of claims 1 to 7 is implemented.

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