An oil-immersed transformer winding temperature measurement method, temperature control method, medium and system

Abstract

The application discloses an oil-immersed transformer winding temperature measuring method, a temperature control method, a medium and a system. The temperature measuring method comprises the following steps: calculating an additional temperature rise value of a transformer winding based on an output current of a transformer secondary side current transformer; and calculating a sum of the additional temperature rise value and a collected transformer oil surface temperature to obtain a transformer winding temperature. The temperature control method comprises the following steps: obtaining the transformer winding temperature by using the oil-immersed transformer winding temperature measuring method; and determining a temperature control mode according to an oil surface temperature, the transformer winding temperature and a collected ambient temperature. The application can improve the accuracy of the oil-immersed transformer winding temperature measurement, and the oil temperature control means is more flexible and efficient.

Description

Technical Field

[0001] This invention relates to the field of transformer winding technology, and in particular to a method for measuring and controlling the temperature of an oil-immersed transformer winding, a medium, and a system. Background Technology

[0002] Currently, oil-immersed transformer winding temperature measurement technology is generally divided into direct measurement methods and indirect measurement methods. Direct measurement methods typically involve contact fiber optic temperature measurement, while indirect measurement methods involve analog measurement. Analog measurement simulates the relationship between the oil surface temperature of the oil-immersed transformer and the temperature difference between the transformer winding and the copper oil. Furthermore, temperature control simply involves activating a fan to cool the transformer when the temperature exceeds a certain set point.

[0003] The current indirect measurement method involves converting the output current of the transformer's secondary current transformer into a small current using an electromagnetic induction coil with a certain turns ratio as a converter. This current is then used to heat the temperature sensor bulb of the transformer's temperature controller, causing it to generate a simulated temperature rise similar to that of the transformer windings. However, this method has several drawbacks: the current transformer's turns ratio has errors, and there are losses in transferring the energy of the current after the turns ratio to the temperature sensor bulb, leading to even greater temperature errors; the transformer's secondary current transformer is prone to open circuits when connected to the converter, and the converter is easily damaged; the converter's heating efficiency is highly dependent on the load and is unstable; and the temperature control is simply a single-threshold triggered mechanical control, which cannot achieve flexible and efficient cooling. Summary of the Invention

[0004] This invention provides a method, control method, medium, and system for measuring the temperature of oil-immersed transformer windings, in order to solve the problem of inaccurate temperature measurement of oil-immersed transformer windings in the prior art.

[0005] Firstly, a method for measuring the temperature of oil-immersed transformer windings is provided, including:

[0006] The additional temperature rise of the transformer winding is calculated based on the output current of the transformer secondary current transformer.

[0007] The transformer winding temperature is obtained by summing the additional temperature rise with the collected transformer oil surface temperature.

[0008] In a second aspect, a computer-readable storage medium is provided, wherein computer program instructions are stored thereon; when executed by a processor, the computer program instructions implement the oil-immersed transformer winding temperature measurement method as described in the first aspect embodiment.

[0009] Thirdly, an oil-immersed transformer winding temperature measurement system is provided, comprising: a computer-readable storage medium as described in the second aspect embodiment.

[0010] Fourthly, a method for controlling the temperature of oil-immersed transformer windings is provided, comprising:

[0011] The transformer winding temperature is obtained using the oil-immersed transformer winding temperature measurement method described in the first aspect embodiment.

[0012] The temperature control method is determined based on the oil surface temperature, transformer winding temperature, and ambient temperature.

[0013] Fifthly, a computer-readable storage medium is provided, wherein computer program instructions are stored thereon; when executed by a processor, the computer program instructions implement the oil-immersed transformer winding temperature control method as described in the fourth aspect embodiment.

[0014] In a sixth aspect, an oil-immersed transformer winding temperature control system is provided, comprising: a computer-readable storage medium as described in the fifth aspect embodiment.

[0015] Thus, the embodiments of the present invention can improve the accuracy of winding temperature measurement of oil-immersed transformers, reduce the probability of equipment damage caused by on-site misoperation, and improve the efficiency of transformer cooling. Based on different conditions of winding temperature, oil surface temperature and ambient temperature, different levels are made, and different control methods corresponding to different levels are used to control the output of switching quantities, making the oil temperature control method more flexible and efficient. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the 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.

[0017] Figure 1 This is a flowchart of the oil-immersed transformer winding temperature measurement method according to an embodiment of the present invention;

[0018] Figure 2 This is a structural block diagram of the oil-immersed transformer winding temperature measurement system according to an embodiment of the present invention;

[0019] Figure 3 This is a flowchart of the oil-immersed transformer winding temperature control method according to an embodiment of the present invention;

[0020] Figure 4 This is a structural block diagram of the oil-immersed transformer winding temperature control system according to an embodiment of the present invention. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] This invention discloses a method for measuring the temperature of oil-immersed transformer windings. For example... Figure 1 As shown, the method of this embodiment of the invention includes the following steps:

[0023] Step S101: Calculate the additional temperature rise of the transformer winding based on the output current of the transformer secondary current transformer.

[0024] Specifically, this step includes the following process:

[0025] 1. Calculate the product of the output current of the transformer secondary current transformer and the current temperature rise coefficient of the transformer winding to obtain the transformer winding current.

[0026] Take I CT K represents the output current of the secondary current transformer of the transformer. CT Let I represent the current temperature rise coefficient of the transformer winding, and let I represent the transformer winding current. The formula for calculating the transformer winding current can be expressed as: I = I0 CT ×K CT .

[0027] The output current of the transformer secondary current transformer can be acquired by a Hall sensor.

[0028] The current temperature rise coefficient of the transformer winding is equal to the product of the initial temperature rise coefficient of the transformer winding and the measured current temperature rise value of the winding under applied current, then divided by the measured initial temperature rise value of the winding under applied current. The initial temperature rise coefficient of the transformer winding can be provided by the manufacturer. (Using K...) CT0 ΔT represents the initial temperature rise coefficient of the transformer winding. m ΔT represents the current temperature rise of the winding under applied current. m0 This represents the initial temperature rise of the winding under applied current. The formula for calculating the current temperature rise coefficient of transformer oil can be expressed as: K CT =K CT0 ×ΔT m / ΔT m0 .

[0029] 2. Calculate the product of the square of the transformer winding current and the DC resistance of the transformer winding to obtain the heat of the transformer winding.

[0030] Let R represent the DC resistance of the transformer winding and Q represent the heat of the transformer winding. The formula for calculating the heat of the transformer winding can be expressed as: Q = I 2 ×R. The DC resistance of the transformer windings can be provided by the manufacturer.

[0031] 3. Calculate the first product of the heat of the transformer winding and the distance between the transformer oil temperature controller and the transformer winding, and calculate the second product of the current thermal conductivity of the transformer oil and the surface area of ​​the transformer winding in contact with the oil.

[0032] Let L represent the distance between the transformer oil temperature controller and the transformer windings. The formula for calculating the first product can be expressed as: Q × L. The distance between the transformer oil temperature controller and the transformer windings can be provided by the manufacturer.

[0033] Let K represent the current thermal conductivity of the transformer oil, and A represent the surface area of ​​the transformer winding in contact with the oil. The formula for calculating the second product can be expressed as: K × A. The surface area of ​​the transformer winding in contact with the oil can be provided by the manufacturer.

[0034] The current thermal conductivity of the transformer oil is equal to the product of the initial thermal conductivity of the transformer oil and the measured current temperature rise of the winding under applied current, divided by the measured initial temperature rise of the winding under applied current. Let K0 represent the initial thermal conductivity of the transformer oil, and ΔT... m ΔT represents the current temperature rise of the winding under applied current. m0 The initial temperature rise of the winding under applied current is represented by the formula for calculating the current thermal conductivity of transformer oil, which can be expressed as: K = K0 × ΔT m / ΔT m0 The initial thermal conductivity of transformer oil can generally be obtained by consulting the transformer oil's specifications. As transformers age, the impurity content of the transformer oil increases, causing changes in its thermal conductivity.

[0035] 4. Calculate the quotient of the first product and the second product to obtain the additional temperature rise of the transformer winding.

[0036] Let ΔT represent the additional temperature rise of the transformer winding. The formula for calculating the additional temperature rise of the transformer winding can be expressed as: ΔT=Q×L / (K×A).

[0037] The additional temperature rise value is calculated through the above process, making the response speed to the additional temperature rise value faster and more accurate than that of traditional transformer winding temperature controllers.

[0038] Step S102: Calculate the sum of the additional temperature rise and the collected transformer oil surface temperature to obtain the transformer winding temperature.

[0039] Let RW represent the transformer winding temperature and YW represent the transformer oil surface temperature. The formula for calculating the transformer winding temperature can be expressed as: RW=YW+ΔT.

[0040] By using the above-mentioned temperature measurement method, which combines heat calculation with real-time compensation for the thermal conductivity of transformer oil, the accuracy and precision of oil-immersed transformer winding temperature measurement are improved. This reduces the number of converters connected, avoiding the problems of open circuits and grounding faults that are easily caused when secondary current transformers are connected to converters. It also avoids the influence of load on converter heating efficiency, thus improving the accuracy of measurement.

[0041] Furthermore, embodiments of the present invention also provide a computer-readable storage medium storing computer program instructions; when the computer program instructions are executed by a processor, they implement the oil-immersed transformer winding temperature measurement method as described in the above embodiments.

[0042] Furthermore, embodiments of the present invention also provide an oil-immersed transformer winding temperature measurement system, comprising: a computer-readable storage medium as described in the above embodiments.

[0043] Specifically, such as Figure 2 As shown, the temperature measurement system includes: a central processing unit 1, a data acquisition unit 2, a first temperature sensor 3, a Hall sensor 4, a second temperature sensor 5, a touch screen 6, an analog winding 7, and a constant current source 8. The central processing unit 1 is electrically connected to the data acquisition unit 2, the touch screen 6, and the constant current source 8. The data acquisition unit 2 is also electrically connected to the first temperature sensor 3, the Hall sensor 4, and the second temperature sensor 5. The analog winding 7 is electrically connected to the constant current source 8.

[0044] Hall sensor 4 is used to collect the output current of the current transformer on the secondary side of the transformer. The central processing unit 1 controls the data acquisition unit 2 to obtain the magnitude of the output current from Hall sensor 4, which is generally 0 to 10A with an accuracy of ±0.1mA. The measurement of Hall sensor 4 is more accurate, so the calculated additional temperature rise value is also more accurate, and there will be no false alarms.

[0045] The first temperature sensor 3 is used to measure the transformer oil surface temperature.

[0046] The second temperature sensor 5, the simulated winding 7, and the constant current source 8 are used to achieve real-time compensation of the transformer oil's thermal conductivity. The second temperature sensor 5 measures the temperature rise of the winding under applied current, thus obtaining the current temperature rise and the initial temperature rise of the winding under applied current. Both the second temperature sensor 5 and the simulated winding 7 are immersed in the transformer oil being tested, and the distance between the second temperature sensor 5 and the simulated winding 7 is set to a fixed value, for example, 5 cm.

[0047] The touchscreen 6 is used to input the output current and additional temperature rise value of the transformer secondary current transformer, and can also display the output current of the transformer secondary current transformer, the current transformer oil temperature, and the transformer winding temperature.

[0048] The central processing unit 1 controls the constant current source 8 to apply a fixed DC current (e.g., 1A) to the simulated winding 7, and records the temperature difference between the second temperature sensor 5 when the current is applied and when no current is applied, i.e., the temperature rise of the winding when the current is applied. This value is recorded as ΔT during initial installation. m0 This refers to the initial temperature rise of the winding when the applied current is applied.

[0049] The central processing unit 1 can calculate the temperature of the transformer windings based on the corresponding physical quantities using the oil-immersed transformer winding temperature measurement method.

[0050] When inputting L and K via touchscreen 6 CT0 After K0, A, and R, the output current of the transformer secondary current transformer is measured by Hall sensor 4, the transformer oil temperature YW is measured by the first temperature sensor 3, and the initial temperature rise ΔT of the winding under applied current is measured by the second temperature sensor 5. m0 and the current temperature rise ΔT of the winding under applied current. m The temperature RW of the transformer winding can be obtained by measuring the temperature of the oil-immersed transformer winding.

[0051] This invention also provides a method for temperature control of the windings of an oil-immersed transformer. For example... Figure 2 As shown, the method includes the following steps:

[0052] Step S201: Obtain the transformer winding temperature using an oil-immersed transformer winding temperature measurement method.

[0053] The method for measuring the temperature of the windings of an oil-immersed transformer is the same as the method described in the previous embodiment, and will not be repeated here.

[0054] Step S202: Determine the temperature control method based on the oil surface temperature, transformer winding temperature, and collected ambient temperature.

[0055] Specifically, this step includes the following situations:

[0056] 1. If the oil surface temperature is greater than the first preset temperature, the difference between the oil surface temperature and the ambient temperature is greater than the second preset temperature, the difference between the transformer winding temperature and the oil surface temperature is greater than the third preset temperature, and the transformer winding temperature is greater than the fourth preset temperature, then start the first preset number of fans and the second preset number of circulating oil pumps.

[0057] 2. If the oil surface temperature is not greater than the first preset temperature, the difference between the oil surface temperature and the ambient temperature is not greater than the second preset temperature, the difference between the transformer winding temperature and the oil surface temperature is not greater than the third preset temperature, and the transformer winding temperature is not greater than the fourth preset temperature, then the first preset number of fans and the second preset number of circulating oil pumps shall be stopped.

[0058] 3. If the oil surface temperature is greater than the first preset temperature, the difference between the oil surface temperature and the ambient temperature is not greater than the second preset temperature, the difference between the transformer winding temperature and the oil surface temperature is not greater than the third preset temperature, and the transformer winding temperature is not greater than the fourth preset temperature, then the third preset number of fans will be started.

[0059] Generally, the first and second preset number of groups are the number of fans and circulating oil pumps equipped with the transformer, respectively. The third preset number of groups is half the number of fans equipped with the transformer. For example, the first preset number of groups is 4, the second preset number of groups is 2, and the third preset number of groups is 2.

[0060] The circulating oil pump can be a forced oil circulation pump.

[0061] The above temperature control method is used to classify different situations and adopt the corresponding control methods to control the output of the switching quantity, making the oil temperature control more flexible and efficient.

[0062] The first, second, third, and fourth preset temperatures can be set based on experience.

[0063] Furthermore, for more precise temperature control, preferably, the method of this embodiment of the invention can also set applicable temperature control conditions. The applicable conditions are: lifespan loss is less than a preset lifespan loss threshold.

[0064] Where S represents lifetime loss, t n This indicates the time of the nth change in transformer winding temperature within a preset time period, typically one day, h. n Represents time t n The corresponding transformer aging rate is then S = t1×h1 + t2×h2 + t3×h3 + … t n ×h n The preset threshold can be set based on experience; for example, the preset lifespan loss threshold is 24.

[0065] The transformer aging rate h is defined as follows: According to the load guidelines, the transformer aging rate when the transformer winding temperature is 98℃ is set as "1". Therefore, when the transformer winding temperature drops to 92℃, the transformer aging rate is "0.5", and when the transformer winding temperature rises to 104℃, the transformer aging rate is "2", and so on. That is, for every 6K increase, the transformer aging rate doubles compared to the previous aging rate, becoming 4, 8, 16, etc. Similarly, for every 6K decrease, the transformer aging rate is halved compared to the previous aging rate. That is, the aging rate at 86℃ is 0.25, at 80℃ it is 0.125, and so on.

[0066] Therefore, when the life loss is less than the preset threshold, the first preset temperature, the second preset temperature, the third preset temperature and the fourth preset temperature are determined according to the additional temperature rise of the transformer winding. Thus, the first preset temperature, the second preset temperature, the third preset temperature and the fourth preset temperature can be dynamically set according to the current situation, making them more accurate.

[0067] Specifically, the correspondence between the additional temperature rise of the transformer winding and the first, second, third, and fourth preset temperatures includes the following situations:

[0068] (1) When the additional temperature rise of the transformer winding is greater than the first preset threshold, the first preset temperature is set as the first temperature value, the second preset temperature is set as the second temperature value, the third preset temperature is set as the third temperature value, and the fourth preset temperature is set as the fourth temperature value.

[0069] (2) When the additional temperature rise of the transformer winding is not greater than the first preset threshold and is greater than the second preset value, the first preset temperature is set as the fifth temperature value, the second preset temperature is set as the sixth temperature value, the third preset temperature is set as the seventh temperature value, and the fourth preset temperature is set as the eighth temperature value.

[0070] (3) When the additional temperature rise of the transformer winding is not greater than the second preset threshold and is greater than the third preset value, the first preset temperature is set as the ninth temperature value, the second preset temperature is set as the tenth temperature value, the third preset temperature is set as the eleventh temperature value, and the fourth preset temperature is set as the twelfth temperature value.

[0071] (4) When the additional temperature rise of the transformer winding is not greater than the third preset threshold and not less than the fourth preset value, the first preset temperature is set as the thirteenth temperature value, the second preset temperature is set as the fourteenth temperature value, the third preset temperature is set as the fifteenth temperature value, and the fourth preset temperature is set as the sixteenth temperature value.

[0072] The first to fourth preset thresholds and the first to sixteenth temperature values ​​mentioned above can all be set based on experience.

[0073] Furthermore, embodiments of the present invention also provide a computer-readable storage medium storing computer program instructions; when the computer program instructions are executed by a processor, they implement the oil-immersed transformer winding temperature control method as described in the above embodiments.

[0074] Furthermore, embodiments of the present invention also provide an oil-immersed transformer winding temperature control system, comprising: a computer-readable storage medium as described in the above embodiments.

[0075] Specifically, such as Figure 4 As shown, in addition to the structure of the temperature measurement system described above, the temperature control system also includes: an ambient temperature sensor 9 and a switch output module 10. The central processing unit 1 is electrically connected to the switch output module 10. The data acquisition unit 2 is electrically connected to the ambient temperature sensor 9.

[0076] Ambient temperature sensor 9 is used to collect the current ambient temperature.

[0077] The digital output module 10 is used to control the transformer circulating oil pump and fan.

[0078] The ambient temperature sensor 9 collects the ambient temperature and the transformer winding temperature together and transmits them to the central processing unit 1. The central processing unit 1 calculates the temperature difference between the transformer winding and the ambient temperature, and controls the switch output module 10 with different control methods corresponding to different levels set by the software, so that it controls the transformer circulating oil pump and fan to perform cooling treatment.

[0079] By incorporating ambient temperature, more precise transformer oil surface temperature, and transformer winding temperature data, intelligent temperature control can be implemented through intelligent analysis by the central processing unit 1, thereby effectively initiating cooling measures.

[0080] The following is a specific application example to further illustrate the solution of the present invention.

[0081] Taking a 220kV transformer (SFP10-260000 / 220) as an example, there are 2 sets of transformer circulating oil pumps and 4 sets of transformer fans. The distance L between the transformer oil temperature controller and the transformer windings is 1m. The calculated current thermal conductivity K of the transformer oil is 240. The DC resistance R of the transformer windings is 0.3Ω. The calculated current temperature rise coefficient K of the transformer windings is... CT The temperature is 401 W / m℃. The surface area A of the transformer winding in contact with the oil is 18 m². 2 The experimental data are shown in Table 1.

[0082] If the measured transformer oil temperature is 51℃ and the output current of the transformer secondary current transformer is 3A, then the additional temperature rise of the transformer winding is 21.5℃, obtained through the temperature measurement method of this embodiment. Therefore, the temperature of the transformer winding is 51 + 21.5 = 72.5℃.

[0083] Table 1 Experimental Data

[0084]

[0085] As can be seen from the comparison in Table 1, the transformer winding temperature calculated by the method of the present invention is similar to the winding temperature obtained by transformer fiber optic temperature measurement, indicating that the calculation results of the method of the present invention are accurate.

[0086] The ambient temperature was 39℃. The ambient temperature of 39℃, the transformer oil surface temperature of 51℃, and the transformer winding temperature of 72.5℃ were combined and calculated.

[0087] The central processing unit stores a first preset temperature, a second preset temperature, a third preset temperature, and a fourth preset temperature. The central processing unit adjusts these preset temperatures based on the additional temperature rise ΔT of the transformer windings and the aging rate h. The central processing unit records the winding temperature changes over a day and calculates the lifespan loss S.

[0088] When S<24, the temperature control method of this embodiment of the invention can be applied. The central processing unit determines the first preset temperature, the second preset temperature, the third preset temperature, and the fourth preset temperature according to the additional temperature rise value of the transformer winding through internal commands, thereby controlling the transformer's fan and forced oil circulation to achieve closed-loop control.

[0089] When the additional temperature rise ΔT of the transformer winding is greater than 50℃, the first preset temperature is 50℃, the second preset temperature is 20℃, the third preset temperature is 20℃, and the fourth preset temperature is 90℃; when 50℃ ≥ ΔT > 20℃, the first preset temperature is 55℃, the second preset temperature is 25℃, the third preset temperature is 25℃, and the fourth preset temperature is 80℃; when 20℃ ≥ ΔT > 10℃, the first preset temperature is 55℃, the second preset temperature is 10℃, the third preset temperature is 15℃, and the fourth preset temperature is 70℃; when 10℃ ≥ ΔT ≥ 0℃, the first preset temperature is 55℃, the second preset temperature is 10℃, the third preset temperature is 10℃, and the fourth preset temperature is 70℃.

[0090] In summary, the embodiments of the present invention can improve the accuracy of winding temperature measurement of oil-immersed transformers, reduce the probability of equipment damage caused by on-site misoperation, and improve the efficiency of transformer cooling. Furthermore, real-time compensation for the thermal conductivity of transformer oil is incorporated, eliminating errors in winding temperature measurement caused by changes in the thermal conductivity of transformer oil during long-term use. Based on different conditions of winding temperature, oil surface temperature, and ambient temperature, different levels are implemented, and different control methods corresponding to these levels are used to control the output of the switching quantities, making oil temperature control more flexible and efficient.

[0091] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for measuring the temperature of an oil-immersed transformer winding, characterized in that, include: The additional temperature rise of the transformer winding is calculated based on the output current of the transformer secondary current transformer. The transformer winding temperature is obtained by summing the additional temperature rise with the collected transformer oil surface temperature. The step of calculating the additional temperature rise of the transformer winding based on the output current of the transformer secondary current transformer includes: The transformer winding current is obtained by multiplying the output current of the transformer secondary current transformer with the current temperature rise coefficient of the transformer winding. The heat of the transformer winding is obtained by multiplying the square of the transformer winding current by the DC resistance of the transformer winding. Calculate the first product of the heat of the transformer winding and the distance between the transformer oil surface temperature controller and the transformer winding, and calculate the second product of the current thermal conductivity of the transformer oil and the surface area of ​​the transformer winding in contact with the oil. The additional temperature rise of the transformer winding is obtained by calculating the quotient of the first product and the second product. The transformer winding temperature rise coefficient is equal to the quotient obtained by multiplying the initial temperature rise coefficient of the transformer winding by the measured current temperature rise value of the winding under the applied current, and then dividing by the measured initial temperature rise value of the winding under the applied current. The current thermal conductivity of the transformer oil is equal to the quotient obtained by multiplying the initial thermal conductivity of the transformer oil by the measured current temperature rise of the winding under the applied current, and then dividing by the measured initial temperature rise of the winding under the applied current.

2. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer program instructions; when the computer program instructions are executed by a processor, they implement the oil-immersed transformer winding temperature measurement method as described in claim 1.

3. A temperature measurement system for oil-immersed transformer windings, characterized in that, include: The computer-readable storage medium as described in claim 2.

4. A method for controlling the temperature of an oil-immersed transformer winding, characterized in that, include: The transformer winding temperature is obtained using the oil-immersed transformer winding temperature measurement method as described in claim 1. The temperature control method is determined based on the oil surface temperature, transformer winding temperature, and ambient temperature.

5. The method for controlling the temperature of oil-immersed transformer windings according to claim 4, characterized in that, The step of determining the temperature control method includes: If the oil surface temperature is greater than the first preset temperature, the difference between the oil surface temperature and the ambient temperature is greater than the second preset temperature, the difference between the transformer winding temperature and the oil surface temperature is greater than the third preset temperature, and the transformer winding temperature is greater than the fourth preset temperature, then the first preset number of fans and the second preset number of circulating oil pumps will be started. If the oil surface temperature is not greater than the first preset temperature, the difference between the oil surface temperature and the ambient temperature is not greater than the second preset temperature, the difference between the transformer winding temperature and the oil surface temperature is not greater than the third preset temperature, and the transformer winding temperature is not greater than the fourth preset temperature, then the first preset number of fans and the second preset number of circulating oil pumps will be stopped. If the oil surface temperature is greater than the first preset temperature, the difference between the oil surface temperature and the ambient temperature is not greater than the second preset temperature, the difference between the transformer winding temperature and the oil surface temperature is not greater than the third preset temperature, and the transformer winding temperature is not greater than the fourth preset temperature, then the third preset number of fans will be started.

6. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer program instructions; when the computer program instructions are executed by a processor, they implement the oil-immersed transformer winding temperature control method as described in any one of claims 4 to 5.

7. A temperature control system for oil-immersed transformer windings, characterized in that, include: The computer-readable storage medium as described in claim 6.

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