Methods, apparatus and systems for measuring moisture content in non-operational oil-filled transformers

Abstract

This invention relates to the field of transformer testing technology, specifically a method, apparatus, and system for measuring the moisture content in an unoperated oil-filled transformer. The method includes obtaining the transformer's internal temperature and relative humidity; determining the transformer's internal dew point using the internal temperature and relative humidity; obtaining the internal moisture pressure based on the national standard curve relating transformer dew point to moisture partial pressure; and determining the internal moisture content based on the calibration curve relating moisture partial pressure to moisture content. This invention can quickly calculate the transformer's internal moisture content using relevant on-site measurement data. Compared to the existing method of taking oil samples and sending them to the power supply bureau's oil testing team for testing, this method is more efficient and saves manpower and resources, providing rapid and effective data support for transformer commissioning.

Description

Technical Field

[0001] This invention relates to the field of transformer testing technology, specifically a method, apparatus, and system for measuring the moisture content in an unoperated oil-filled transformer. Background Technology

[0002] Substations contain numerous pieces of equipment, including transformers in cold standby mode, which can lead to hydrogen accumulation. During transformer production, transportation, installation, commissioning, and placement, moisture can accumulate inside the transformer tank due to dampness. During production and commissioning, tests such as drying, impregnation, and high-voltage application are required, causing some internal insulation materials to decompose and produce gases like hydrogen under heat and electricity. Metals such as iron and copper inside the transformer act as catalysts in the oxidation reaction of transformer oil, significantly accelerating its oxidation rate. Stainless steel is often used inside transformers; during on-site placement, the nickel content in the stainless steel can cause dehydrogenation when the transformer oil undergoes oxidation at high temperatures. Excessive oil filling can also prevent air circulation inside the transformer, increasing humidity. The accumulation and superposition of these factors will cause an increase in moisture in the insulation of the transformer, which will bring instability to the transformer after it is put into operation from standby. Therefore, it is necessary to measure the moisture content (trace water) in the standby equipment oil. Generally, there are no oil testing conditions on site, so the oil needs to be taken and sent to the oil testing team of the power supply bureau for testing, which is more cumbersome and takes a certain amount of time. Summary of the Invention

[0003] This invention provides a method, apparatus, and system for measuring the moisture content in an unoperated oil-filled transformer, overcoming the shortcomings of the prior art and effectively solving the problems of cumbersome detection process and low efficiency in existing transformer moisture detection.

[0004] One of the technical solutions of this invention is achieved through the following measures: a method for measuring the moisture content in an unoperated oil-filled transformer, comprising:

[0005] To obtain the internal temperature and relative humidity of the transformer;

[0006] The internal dew point of the transformer is obtained by using the internal temperature and relative humidity of the transformer.

[0007]

[0008] Among them, T d Here, RH is the internal dew point of the transformer; T is the internal relative humidity of the transformer; and RH is the internal temperature of the transformer. Both a and b are constants;

[0009] Based on the specified curve of the relationship between transformer dew point and moisture partial pressure in the national standard, the moisture partial pressure inside the transformer is obtained by using the internal dew point of the transformer.

[0010] Based on the calibration curve of transformer moisture partial pressure and moisture content, the moisture content inside the transformer is obtained by using the moisture partial pressure inside the transformer.

[0011] The following are further optimizations and / or improvements to the above-mentioned technical solution:

[0012] The above-mentioned methods for obtaining the internal temperature and relative humidity of the transformer include:

[0013] Obtain the standard value and measured value of the DC resistance of the transformer;

[0014] Based on the DC resistance-temperature conversion formula, the DC resistance-temperature calculation value is obtained by using the standard value of DC resistance of the transformer and the measured value of DC resistance.

[0015] Obtain multiple DC resistance measurements of the transformer, calculate multiple DC resistance temperature values, and take the average value as the internal temperature of the transformer.

[0016] The relative humidity of the respirator is obtained, and the relative humidity inside the transformer is obtained based on the relative humidity of the respirator using the following formula;

[0017]

[0018] Among them, RH 呼吸器 V1 / V2 is the relative humidity of the respirator; V1 / V2 is the ratio of transformer oil filling volume to oil tank volume; Δt3 / Δt4 is the temperature correction coefficient; Δt3 is the average of the highest temperature points in the last 5 days; Δt4 is the average of the lowest temperature points in the last 5 days.

[0019] The construction of the calibration curves for the moisture partial pressure versus moisture content of the above-mentioned transformer includes:

[0020] By setting a specific pressure value, the moisture content in the air is measured at different temperatures, and a curve is formed with temperature on the horizontal axis and pressure on the vertical axis to represent the pressure versus moisture content.

[0021] By changing the pressure value and repeating the above steps, the corresponding curves of pressure and moisture content under different pressure values ​​are obtained, thereby forming the calibration curve of transformer moisture pressure and moisture content.

[0022] The formula for obtaining the internal dew point of a transformer using its internal temperature and relative humidity is applicable within the following range: 0℃. <T<60℃、1%<RH<100%、0℃<T d <50℃.

[0023] The second technical solution of the present invention is achieved through the following measures: a measuring device for moisture content in an unoperated oil-filled transformer, characterized in that it comprises:

[0024] The data acquisition unit obtains the internal temperature and relative humidity of the transformer.

[0025] The dew point analysis unit uses the internal temperature and relative humidity of the transformer to obtain the internal dew point of the transformer.

[0026]

[0027] Among them, T d Here, RH is the internal dew point of the transformer; T is the internal relative humidity of the transformer; and RH is the internal temperature of the transformer. Both a and b are constants;

[0028] The air pressure analysis unit, based on the specified curve of the relationship between transformer dew point and moisture partial pressure in the national standard, uses the internal dew point of the transformer to obtain the internal moisture partial pressure of the transformer.

[0029] The moisture analysis unit, based on the calibration curve of moisture partial pressure and moisture content in the transformer, uses the moisture partial pressure inside the transformer to obtain the moisture content inside the transformer.

[0030] The following are further optimizations and / or improvements to the above-mentioned technical solution:

[0031] The aforementioned data acquisition unit includes:

[0032] The internal temperature acquisition module obtains the standard value and measured value of the transformer's DC resistance; based on the DC resistance-temperature conversion formula, it uses the standard value and measured value of the transformer's DC resistance to obtain the calculated value of the DC resistance-temperature; it acquires multiple measured values ​​of the transformer's DC resistance, calculates multiple calculated values ​​of the DC resistance-temperature, and takes the average value as the internal temperature of the transformer.

[0033] The relative humidity acquisition module obtains the relative humidity of the respirator, and based on the relative humidity of the respirator, the relative humidity inside the transformer is obtained using the following formula;

[0034]

[0035] Among them, RH 呼吸器 V1 / V2 is the relative humidity of the respirator; V1 / V2 is the ratio of transformer oil filling volume to oil tank volume; Δt3 / Δt4 is the temperature correction coefficient; Δt3 is the average of the highest temperature points in the last 5 days; Δt4 is the average of the lowest temperature points in the last 5 days.

[0036] The third technical solution of the present invention is achieved through the following measures: a system for measuring the moisture content in an unoperated oil-filled transformer, comprising:

[0037] A device for measuring the moisture content in an unoperated oil-filled transformer, wherein the device for measuring the moisture content in an unoperated oil-filled transformer is as described above.

[0038] An interactive device is used for communication between the operator and the moisture content measuring device in the non-operating oil-filled transformer, enabling the operator to input data, calibrate and set the device through the interactive unit.

[0039] An alarm device is provided, which has an internal alarm threshold to determine in real time whether the internal temperature and moisture content of the transformer exceed the limit. If so, the alarm device will issue an alarm.

[0040] This invention obtains the internal temperature and relative humidity of a transformer after it has been filled with oil and left to stand for a period of time, allowing the internal humidity and pressure to reach equilibrium. It then calculates the internal dew point and, by combining the national standard curves specifying the relationship between transformer dew point and moisture partial pressure, as well as the calibration curves showing the relationship between moisture partial pressure and moisture content, obtains the internal moisture content of the transformer. This method allows for the rapid calculation of the internal moisture content of the transformer using relevant on-site measurement data. Compared to the existing method of taking oil samples and sending them to the power supply bureau's oil testing team for testing, this method is more efficient and saves manpower and resources, providing rapid and effective data support for the transformer's commissioning. Attached Figure Description

[0041] Appendix Figure 1 This is a schematic diagram of the method flow of the present invention.

[0042] Appendix Figure 2 This is a schematic diagram of the method for obtaining the internal temperature and relative humidity of a transformer according to the present invention.

[0043] Appendix Figure 3 This is a schematic diagram of the specified curve relating the transformer dew point to the moisture vapor pressure in this invention.

[0044] Appendix Figure 4 This is a schematic diagram of the method for constructing the calibration curve of transformer moisture partial pressure and moisture content in this invention.

[0045] Appendix Figure 5 This is a schematic diagram of the calibration curve of moisture partial pressure and moisture content of a transformer according to the present invention.

[0046] Appendix Figure 6 This is a schematic diagram of the device structure of the present invention.

[0047] Appendix Figure 7 This is a schematic diagram of the system structure of the present invention. Detailed Implementation

[0048] The present invention is not limited to the following embodiments, and the specific implementation can be determined according to the technical solution of the present invention and the actual situation.

[0049] The present invention will be further described below with reference to embodiments and accompanying drawings:

[0050] Example 1: As shown in the attached document Figure 1 As shown in the figure, an embodiment of the present invention discloses a method for measuring the moisture content in an unoperated oil-filled transformer, comprising:

[0051] Step S110: Obtain the internal temperature and relative humidity of the transformer.

[0052] Step S120: Obtain the internal dew point of the transformer using the internal temperature and relative humidity of the transformer.

[0053]

[0054] Among them, T d Here, RH is the internal dew point of the transformer; T is the internal relative humidity of the transformer; and RH is the internal temperature of the transformer. Both a and b are constants;

[0055] Step S130: Based on the specified curve of the relationship between transformer dew point and moisture partial pressure in the national standard, the moisture partial pressure inside the transformer is obtained using the internal dew point of the transformer.

[0056] Step S140: Based on the calibration curve of transformer moisture partial pressure and moisture content, the moisture content inside the transformer is obtained by using the moisture partial pressure inside the transformer.

[0057] This invention discloses a method for measuring the moisture content in an unoperated oil-filled transformer. After the transformer is filled with oil and left to stand for a period of time, when the internal humidity and pressure reach equilibrium, the internal temperature and relative humidity of the transformer are obtained, the internal dew point of the transformer is calculated, and then the moisture content inside the transformer is obtained by combining the specified curve of the relationship between transformer dew point and moisture partial pressure in the national standard and the calibration curve of transformer moisture partial pressure and moisture content. Based on this method, the moisture content value inside the transformer can be quickly calculated using relevant on-site measurement data. Compared with the existing method of taking oil samples and sending them to the power supply bureau's oil testing team for testing, this method is more efficient and saves manpower and resources, and can provide rapid and effective data support for the transformer to be put into operation.

[0058] Example 2: This embodiment of the invention discloses a method for measuring the moisture content in an unoperated oil-filled transformer, comprising:

[0059] Step S210: Obtain the internal temperature and relative humidity of the transformer.

[0060] As attached Figure 2 As shown, the above steps specifically include:

[0061] Step S211: Obtain the standard value and measured value of the DC resistance of the transformer;

[0062] Step S212: Based on the DC resistance temperature conversion formula, the DC resistance temperature is calculated using the standard value of the transformer's DC resistance and the measured value of the DC resistance.

[0063] The formula for converting DC resistance to temperature in the national standard is shown below:

[0064] R 标准值 =R 测量值 ×(T+75) / (T+Δt1)

[0065] Where T is the material correction factor, T = 235 for copper conductors and T = 225 for aluminum conductors; Δt1 is the DC resistance temperature value (°C) at this time, which is the calculated DC resistance temperature value (°C);

[0066] Step S213: Obtain multiple DC resistance measurement values ​​of the transformer, calculate multiple DC resistance temperature values, and take the average value as the internal temperature of the transformer.

[0067] Step S214: Obtain the relative humidity of the respirator, and obtain the relative humidity inside the transformer based on the relative humidity of the respirator using the following formula;

[0068]

[0069] Among them, RH 呼吸器 Δt3 is the relative humidity of the respirator; V1 / V is the ratio of transformer oil filling volume to oil tank volume; Δt3 / Δt is the temperature correction coefficient; Δt3 is the average of the highest temperature points in the last 5 days; Δt4 is the average of the lowest temperature points in the last 5 days.

[0070] The breather serves two main purposes: first, it connects the air inside the transformer with the outside environment. When the transformer is running, the oil expands as it heats up, releasing internal gases; when the transformer cools down, the oil contracts, drawing in external air, thus maintaining equal air pressure inside and outside the transformer. Second, the breather contains an adsorbent (drying agent) that absorbs moisture and impurities from the air, preventing humid air from directly entering the oil conservator and reducing or damaging the oil's insulation strength. Based on historical data fitting, the relationship between the relative humidity of the breather and the relative humidity inside the transformer is shown below:

[0071] RH 呼吸器 =RH 变压器 ×(V1 / V2)×(Δt3 / Δt4)

[0072] By modifying the above, we obtain the formula for calculating the relative humidity inside the transformer in this embodiment.

[0073] Step S220: Obtain the internal dew point of the transformer using the internal temperature and relative humidity of the transformer.

[0074]

[0075] Among them, T d Here, RH is the internal dew point of the transformer; T is the internal relative humidity of the transformer; and RH is the internal temperature of the transformer. Both a and b are constants;

[0076] The above formula for calculating the dew point inside the transformer can be derived, but is not limited to, using the Magnus-Tetens approximation method. The applicable range of this formula includes: 0℃. <T<60℃、1%<RH<100%、0℃<T d <50℃. Compared to the actual operating conditions during transformer power outage maintenance, this formula covers the vast majority of situations and is sufficient to accurately calculate the internal dew point of the transformer.

[0077] Step S230: Based on the specified curve of the relationship between transformer dew point and moisture partial pressure in the national standard, the moisture partial pressure inside the transformer is obtained using the internal dew point of the transformer.

[0078] The specified curves for the relationship between transformer dew point and moisture vapor pressure in the aforementioned national standards are attached. Figure 3 As shown, converting it into a point table makes it easier to look up, and the corresponding point table is shown in Table 1.

[0079] Step S240: Based on the calibration curve of transformer moisture partial pressure and moisture content, the moisture content inside the transformer is obtained by using the moisture partial pressure inside the transformer.

[0080] As attached Figure 4 As shown, the construction of the calibration curves for the moisture partial pressure versus moisture content of the above-mentioned transformer includes:

[0081] Step S241: Set a specific pressure value, measure the corresponding moisture content in the air at different temperatures, and form a curve showing the relationship between pressure and moisture content with temperature as the horizontal axis and pressure as the vertical axis.

[0082] Step S242: Change the pressure value and repeat the above steps to obtain the corresponding curves of pressure and moisture content under different pressure values, thereby forming the calibration curve of transformer moisture pressure and moisture content.

[0083] The calibration curves for transformer moisture partial pressure versus moisture content constructed through the above steps can be, but are not limited to, those shown in the attached figure. Figure 5 As shown.

[0084] Example 3: As shown in the attached document Figure 6 As shown, this embodiment of the invention discloses a device for measuring the moisture content in an unoperated oil-filled transformer, comprising:

[0085] The data acquisition unit obtains the internal temperature and relative humidity of the transformer.

[0086] The dew point analysis unit uses the internal temperature and relative humidity of the transformer to obtain the internal dew point of the transformer.

[0087]

[0088] Among them, T d Here, RH is the internal dew point of the transformer; T is the internal relative humidity of the transformer; and RH is the internal temperature of the transformer. Both a and b are constants;

[0089] The air pressure analysis unit, based on the specified curve of the relationship between transformer dew point and moisture partial pressure in the national standard, uses the internal dew point of the transformer to obtain the internal moisture partial pressure of the transformer.

[0090] The moisture analysis unit, based on the calibration curve of moisture partial pressure and moisture content in the transformer, uses the moisture partial pressure inside the transformer to obtain the moisture content inside the transformer.

[0091] The data acquisition unit includes:

[0092] The internal temperature acquisition module obtains the standard value and measured value of the transformer's DC resistance; based on the DC resistance-temperature conversion formula, it uses the standard value and measured value of the transformer's DC resistance to obtain the calculated value of the DC resistance-temperature; it acquires multiple measured values ​​of the transformer's DC resistance, calculates multiple calculated values ​​of the DC resistance-temperature, and takes the average value as the internal temperature of the transformer.

[0093] The formula for converting DC resistance to temperature in the national standard is shown below:

[0094] R 标准值 =R 测量值 ×(T+75) / (T+Δt1)

[0095] Where T is the material correction factor, T = 235 for copper conductors and T = 225 for aluminum conductors; Δt1 is the DC resistance temperature value (°C) at this time, which is the calculated DC resistance temperature value (°C);

[0096] The relative humidity acquisition module obtains the relative humidity of the respirator, and based on the relative humidity of the respirator, the relative humidity inside the transformer is obtained using the following formula;

[0097]

[0098] Among them, RH 呼吸器 Δt3 represents the relative humidity of the respirator; V1V represents the ratio of transformer oil filling volume to oil tank volume; Δt3 represents the temperature correction coefficient; Δt3 represents the average of the highest temperatures over the past 5 days; Δt4 represents the average of the lowest temperatures over the past 5 days.

[0099] Example 4: As shown in the appendix Figure 7 As shown, this embodiment of the invention discloses a system for measuring the moisture content in an unoperated oil-filled transformer, comprising:

[0100] A device for measuring the moisture content in an unoperated oil-filled transformer, wherein the device for measuring the moisture content in an unoperated oil-filled transformer is the same as the device for measuring the moisture content in an unoperated oil-filled transformer described in the above embodiment.

[0101] An interactive device is used for communication between the operator and the moisture content measuring device in the non-operating oil-filled transformer, enabling the operator to input data, calibrate and set the device through the interactive unit.

[0102] An alarm device is provided, which has an internal alarm threshold to determine in real time whether the internal temperature and moisture content of the transformer exceed the limit. If so, the alarm device will issue an alarm.

[0103] The aforementioned interactive device may include a communication interface and a human-machine interaction device. The communication interface may be a serial port. The human-machine interaction device is connected to the moisture content measuring device in the non-operating oil-filled transformer through the serial port to perform data entry, device calibration, and device standardization for the moisture content measuring device in the non-operating oil-filled transformer.

[0104] The alarm device mentioned above may include a buzzer alarm and a control chip. The control chip determines whether the internal temperature and moisture content of the transformer exceed the limits, and in response, controls the buzzer alarm to sound an alarm.

[0105] Example 5: This embodiment of the invention discloses a storage medium storing a computer program that can be read by a computer. The computer program is configured to execute a method for measuring the moisture content in an unrunning oil-filled transformer when it is in operation.

[0106] The aforementioned storage media may include, but are not limited to, USB flash drives, read-only memory, portable hard drives, magnetic disks, optical disks, and other media capable of storing computer programs.

[0107] Example 6: This embodiment of the invention discloses an electronic device, including a processor and a memory, wherein the memory stores a computer program, which is loaded and executed by the processor to implement a method for measuring the moisture content in an unoperated oil-filled transformer.

[0108] The processor described above can be a central processing unit (CPU), a general-purpose processor, a digital signal processor (DSP), an ASIC, an FPGA, or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. It can implement or execute the various exemplary logic blocks, modules, and circuits described in conjunction with the disclosure of this application. It can also be a combination that implements computational functions, such as a combination of one or more microprocessors, a combination of a DSP and a microprocessor, etc. The memory can include, but is not limited to, various media capable of storing computer programs, such as USB flash drives, read-only memory, portable hard drives, magnetic disks, or optical disks.

[0109] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. The solutions in the embodiments of this application can be implemented in various computer languages, such as the object-oriented programming language Java and the interpreted scripting language JavaScript.

[0110] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0111] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0112] The above technical features constitute the preferred embodiment of the present invention, which has strong adaptability and optimal implementation effect. Unnecessary technical features can be added or removed according to actual needs to meet the requirements of different situations.

[0113] Table 1

[0114]

Claims

1. A method of measuring moisture content in an unenergized oil-filled transformer, characterized by, The method comprises the following steps: obtaining the internal temperature of the transformer and the internal relative humidity of the transformer; obtaining the internal dew point of the transformer by using the internal temperature of the transformer and the internal relative humidity of the transformer; wherein, is the dew point inside the transformer; is the relative humidity inside the transformer; T is the temperature inside the transformer; ; a and b are constants; obtaining the internal moisture partial pressure of the transformer by using the internal dew point of the transformer based on the curve of the relationship between the transformer dew point and the moisture partial pressure in the national standard; obtaining the internal moisture content of the transformer by using the internal moisture partial pressure of the transformer based on the calibration curve of the relationship between the transformer moisture partial pressure and the moisture content; wherein the obtaining of the internal temperature of the transformer and the internal relative humidity of the transformer comprises the following steps: obtaining the standard value and the measured value of the direct current resistance of the transformer; obtaining the direct current resistance temperature calculation value by using the standard value and the measured value of the direct current resistance of the transformer based on the direct current resistance temperature conversion formula, wherein the direct current resistance temperature conversion formula is as follows: wherein, t is the material correction factor, if it is a copper conductor: t = 235; if it is an aluminum conductor: t = 225; is the DC resistance temperature value at this time, i.e. the DC resistance temperature calculation value; obtaining the internal temperature of the transformer by obtaining multiple direct current resistance measured values of the transformer and multiple direct current resistance temperature calculation values, and taking the average value as the internal temperature of the transformer; obtaining the internal relative humidity of the transformer based on the relative humidity of the respirator by the following formula: wherein, is the relative humidity of the respirator; is the transformer oil filling and oil tank volume ratio; is the temperature correction coefficient; is the average of the highest temperature in the last 5 days; is the average of the lowest temperature in the last 5 days.

2. The method of claim 1, wherein the moisture content is measured by a method comprising: The construction of the calibration curve of the relationship between the transformer moisture partial pressure and the moisture content comprises the following steps: setting a specific pressure value, measuring the corresponding moisture content value in the air at different temperatures to form a corresponding curve of the pressure and the moisture content value with the temperature as the horizontal axis and the pressure as the vertical axis; changing the pressure value, repeating the above steps to obtain the corresponding curve of the pressure and the moisture content value at different pressure values, thereby forming the calibration curve of the relationship between the transformer moisture partial pressure and the moisture content.

3. The method of claim 1 or 2, wherein The formula for obtaining the dew point inside the transformer using the internal temperature of the transformer and the relative humidity inside the transformer is applicable to a range of 0°C T <60°C, 1% <100%, 0°C <50°C.

4. A moisture content measuring device for a non-operating oil-filled transformer using the method according to any one of claims 1 to 3, characterized in that, The method comprises the following steps: a data acquisition unit is configured to obtain the internal temperature of the transformer and the internal relative humidity of the transformer; a dew point analysis unit is configured to obtain the internal dew point of the transformer by using the internal temperature of the transformer and the internal relative humidity of the transformer; wherein, is the dew point inside the transformer; is the relative humidity inside the transformer; T is the temperature inside the transformer; ; a and b are constants; a gas pressure analysis unit is configured to obtain the internal moisture partial pressure of the transformer by using the internal dew point of the transformer based on the curve of the relationship between the transformer dew point and the moisture partial pressure in the national standard; a moisture analysis unit is configured to obtain the internal moisture content of the transformer by using the internal moisture partial pressure of the transformer based on the calibration curve of the relationship between the transformer moisture partial pressure and the moisture content.

5. The apparatus for measuring moisture content in an unenergized oil-filled transformer according to claim 4, wherein The data acquisition unit comprises: an internal temperature acquisition module is configured to obtain the standard value and the measured value of the direct current resistance of the transformer, and obtain the direct current resistance temperature calculation value by using the standard value and the measured value of the direct current resistance of the transformer based on the direct current resistance temperature conversion formula; the internal temperature of the transformer is obtained by obtaining multiple direct current resistance measured values of the transformer and multiple direct current resistance temperature calculation values, and taking the average value as the internal temperature of the transformer; wherein the direct current resistance temperature conversion formula is as follows: wherein, t is the material correction factor; is the DC resistance temperature value at this time, i.e. the DC resistance temperature calculated value; a relative humidity acquisition module is configured to obtain the internal relative humidity of the transformer based on the relative humidity of the respirator by the following formula: wherein, is the relative humidity of the respirator; is the transformer oil filling and oil tank volume ratio; is the temperature correction coefficient; is the average of the highest temperature in the last 5 days; is the average of the lowest temperature in the last 5 days.

6. A system for measuring moisture content in an unenergized oil-filled transformer, comprising: The method comprises the following steps: a device for measuring the moisture content in an un-operated oil-filled transformer, wherein the device for measuring the moisture content in an un-operated oil-filled transformer is the device for measuring the moisture content in an un-operated oil-filled transformer as claimed in any one of claims 4 to 5. An interactive device is used for the operator to communicate with the moisture content measuring device in the non-running oil-filled transformer, so that the operator enters data, calibrates and calibrates the moisture content measuring device in the non-running oil-filled transformer through the interactive unit. An alarm device is internally provided with an alarm threshold value, which can judge whether the temperature and moisture content in the transformer are out of limit in real time, and the alarm device will alarm in response.

7. A storage medium, characterized by The storage medium stores a computer program readable by a computer, and the computer program is set to execute the moisture content measuring method in the non-running oil-filled transformer as claimed in any one of claims 1 to 3.

8. An electronic device, comprising: The computer program is loaded and executed by the processor to realize the moisture content measuring method in the non-running oil-filled transformer as claimed in any one of claims 1 to 3.

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