A method, system, equipment, and medium for calibrating transformer winding temperature controllers.

Abstract

This invention discloses a method, system, equipment, and medium for calibrating transformer winding temperature controllers, comprising: responding to a calibration request for the winding temperature controller; acquiring measured values ​​of the target transformer winding temperature, the main transformer load current, and the transformer oil temperature from multiple winding temperature controllers; inputting multiple main transformer load currents into a preset temperature rise function of the target winding temperature controller to obtain the corresponding copper-oil temperature difference value; calculating the sum of the transformer oil temperature and the copper-oil temperature difference value to obtain multiple theoretical values ​​of the target transformer winding temperature; calculating the temperature difference between the measured values ​​of the target transformer winding temperature and the theoretical values ​​of the target transformer winding temperature to obtain multiple accuracy error values ​​of the winding temperature controller; comparing the accuracy error values ​​of the winding temperature controller with a preset accuracy error threshold for the winding temperature controller, and outputting the operating status of the winding temperature controller based on the comparison result. This invention solves the technical problem of long calibration cycles for winding temperature controllers and the lack of effective periodic control and monitoring of measurement accuracy.

Description

Technical Field

[0001] This invention relates to the field of power instrument calibration technology, and in particular to a method, system, equipment and medium for calibrating transformer winding temperature controllers. Background Technology

[0002] Large power transformers are equipped with winding temperature controllers, which measure, display, and remotely transmit the winding temperature during transformer operation. This serves as a crucial parameter for controlling hot spot temperatures in the windings. Furthermore, they function to issue alarms and trip signals when the winding temperature reaches a certain limit. Currently, most large power transformers operating in power systems use thermal simulation methods to measure winding temperature. This method, based on the square relationship between transformer load losses and load current, uses a current matching device and heating elements, along with oil temperature measurements from the winding gauge, to reflect the transformer's winding temperature through temperature superposition.

[0003] Currently, the main transformer winding temperature controller adopts an offline testing method. This involves de-energizing the transformer, manually removing the temperature probe of the winding temperature controller, placing it in a constant temperature bath, connecting a thermal simulation current to the current input terminal of the temperature controller, manually raising the temperature and applying the input current, measuring the temperature controller's indication error and additional temperature rise error, and using the error value to determine whether the winding temperature controller is qualified.

[0004] However, in practical applications, the winding temperature controller is calibrated periodically, typically every three or six years during a power outage. There is no effective periodic control over the winding temperature controller to monitor its measurement accuracy and ensure that accurate temperature measurements are provided under the operating conditions of the main transformer. Summary of the Invention

[0005] This invention provides a method, system, equipment, and medium for calibrating transformer winding temperature controllers, which solves the technical problems of long calibration cycles for winding temperature controllers, lack of effective periodic control of winding temperature controllers, monitoring of the accuracy of winding temperature controller measurements, and ensuring the provision of accurate temperature measurement values ​​under the operating conditions of the main transformer.

[0006] The first aspect of this invention provides a method for calibrating a transformer winding temperature controller, comprising:

[0007] In response to the winding temperature controller calibration request, the target transformer winding temperature measurement value, transformer main transformer load current and transformer oil temperature of multiple winding temperature controllers are collected within the preset calibration period.

[0008] The multiple main transformer load currents are respectively input to the preset target winding temperature controller temperature rise function to obtain the copper oil temperature difference value corresponding to the main transformer load current;

[0009] The sum of the transformer oil temperature and the copper oil temperature difference is calculated to obtain multiple theoretical values ​​of the target transformer winding temperature.

[0010] The temperature difference between the measured temperature value of the target transformer winding and the theoretical temperature value of the target transformer winding are calculated respectively to obtain multiple winding temperature controller accuracy error values;

[0011] The accuracy error value of the winding temperature controller is compared with the preset accuracy error threshold of the winding temperature controller, and the operating status of the winding temperature controller is output based on the comparison result.

[0012] Optionally, before the step of inputting the multiple main transformer load currents to a preset target winding temperature controller temperature rise function to obtain the copper oil temperature difference value corresponding to the main transformer load current, the method includes:

[0013] In response to the copper oil temperature difference detection request, obtain transformer fixed parameter information and winding temperature controller fixed parameter information;

[0014] A heating current calculation function with the main transformer load current as the variable is constructed using the fixed parameter information of the transformer and the fixed parameter information of the winding temperature controller.

[0015] Substitute the heating current calculation function into the preset winding temperature controller temperature rise function to obtain the target winding temperature controller temperature rise function corresponding to the main transformer load current.

[0016] Optionally, the transformer fixed parameters include the transformer rated capacity, transformer rated voltage, temperature sensing winding CT ratio, and transformer rated copper oil temperature difference; the winding temperature controller fixed parameters include the rated heating current corresponding to the transformer rated copper oil temperature difference; the step of constructing a heating current calculation function with the main transformer load current as a variable using the transformer fixed parameter information and the winding temperature controller fixed parameter information includes:

[0017] The rated current of the transformer is obtained by inputting the rated capacity and rated voltage of the transformer into a preset transformer current calculation formula;

[0018] Calculate the first ratio of the rated current of the transformer to the CT ratio of the temperature sensing winding to obtain the winding temperature controller matching current;

[0019] Calculate the second ratio of the rated heating current to the winding temperature controller matching current to obtain the winding temperature controller matching ratio;

[0020] Using the winding temperature controller matching ratio and the temperature measuring winding CT ratio, a function for calculating the heating current is constructed with the main transformer load current as the variable.

[0021] Optionally, the step of comparing the accuracy error value of the winding temperature controller with a preset accuracy error threshold for the winding temperature controller, and outputting the operating status of the winding temperature controller based on the comparison result, includes:

[0022] Select a target percentage probability value from among multiple winding temperature controller accuracy error values, and compare the winding temperature controller accuracy error value corresponding to the target percentage probability value with a preset winding temperature controller accuracy error threshold.

[0023] If the accuracy error value of the winding temperature controller is greater than the accuracy error threshold of the winding temperature controller, then the operating status of the winding temperature controller will be output as abnormal.

[0024] If the accuracy error value of the winding temperature controller is less than or equal to the accuracy error threshold of the winding temperature controller, then the operating status of the winding temperature controller is output as normal.

[0025] A second aspect of the present invention provides a transformer winding temperature controller calibration system, comprising:

[0026] The parameter acquisition module is used to respond to the winding temperature controller calibration request and acquire the target transformer winding temperature measurement value, transformer main load current and transformer oil temperature of multiple winding temperature controllers within a preset calibration period.

[0027] The copper oil temperature difference calculation module is used to input multiple main transformer load currents to the preset target winding temperature controller temperature rise function to obtain the copper oil temperature difference value corresponding to the main transformer load current.

[0028] The target transformer winding temperature theoretical value calculation module is used to calculate the sum of the transformer oil temperature and the copper oil temperature difference to obtain multiple target transformer winding temperature theoretical values.

[0029] The winding temperature controller accuracy error value calculation module is used to calculate the temperature difference between the measured value of the target transformer winding temperature and the theoretical value of the target transformer winding temperature, and obtain multiple winding temperature controller accuracy error values.

[0030] The verification and judgment module is used to compare the accuracy error value of the winding temperature controller with the preset accuracy error threshold of the winding temperature controller, and output the operating status of the winding temperature controller based on the comparison result.

[0031] Optionally, it also includes:

[0032] The fixed parameter acquisition module is used to respond to copper oil temperature difference detection requests and acquire transformer fixed parameter information and winding temperature controller fixed parameter information;

[0033] The heating current calculation function construction module is used to construct a heating current calculation function with the main transformer load current as the variable using the fixed parameter information of the transformer and the fixed parameter information of the winding temperature controller;

[0034] The target winding temperature controller temperature rise function construction module is used to substitute the heating current calculation function into the preset winding temperature controller temperature rise function to obtain the target winding temperature controller temperature rise function corresponding to the main transformer load current.

[0035] Optionally, the transformer fixed parameters include the transformer rated capacity, transformer rated voltage, temperature sensing winding CT ratio, and transformer rated copper oil temperature difference; the winding temperature controller fixed parameters include the rated heating current corresponding to the transformer rated copper oil temperature difference; and the heating current calculation function construction module includes:

[0036] The transformer rated current calculation submodule is used to input the transformer rated capacity and the transformer rated voltage into a preset transformer current calculation formula to obtain the transformer rated current.

[0037] The winding temperature controller matching current calculation submodule is used to calculate the first ratio between the rated current of the transformer and the CT ratio of the temperature measuring winding to obtain the winding temperature controller matching current.

[0038] The winding temperature controller matching ratio calculation submodule is used to calculate the second ratio of the rated heating current to the winding temperature controller matching current to obtain the winding temperature controller matching ratio.

[0039] The heating current calculation function construction submodule is used to construct a heating current calculation function using the winding temperature controller matching ratio and the temperature measuring winding CT ratio, with the main transformer load current as the variable.

[0040] Optionally, the verification and judgment module includes:

[0041] The difference selection submodule is used to select a target percentage probability value among multiple winding temperature controller accuracy error values, and compare the winding temperature controller accuracy error value corresponding to the target percentage probability value with a preset winding temperature controller accuracy error threshold.

[0042] The first operating status output submodule is used to output that the operating status of the winding temperature controller is abnormal if the accuracy error value of the winding temperature controller is greater than the accuracy error threshold of the winding temperature controller.

[0043] The second operating status output submodule is used to output that the operating status of the winding temperature controller is normal if the accuracy error value of the winding temperature controller is less than or equal to the accuracy error threshold of the winding temperature controller.

[0044] A third aspect of the present invention provides an electronic device, including a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor performs the steps of the transformer winding temperature controller calibration method as described above.

[0045] A fourth aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed, implements the transformer winding temperature controller calibration method as described above.

[0046] As can be seen from the above technical solutions, the present invention has the following advantages:

[0047] This invention responds to winding temperature controller calibration requests by collecting measured values ​​of the target transformer winding temperature, the transformer main load current, and the transformer oil temperature within a preset calibration period. Then, the multiple main load currents are input into a preset temperature rise function of the target winding temperature controller to obtain the copper-oil temperature difference value corresponding to each main load current. The copper-oil temperature difference value is calculated by collecting the main load current. The sum of the transformer oil temperature and the copper-oil temperature difference value is then calculated to obtain the theoretical values ​​of the target transformer winding temperature. The temperature difference between the measured target transformer winding temperature value and the theoretical target transformer winding temperature value is then calculated to obtain the accuracy error values ​​of the multiple winding temperature controllers. Finally, the accuracy error values ​​of the winding temperature controllers are compared with a preset accuracy error threshold, and the operating status of the winding temperature controllers is output based on the comparison results. This invention periodically calculates the accuracy error value of the winding temperature controller during operation and compares it with a preset accuracy error threshold to determine the operating status of the winding temperature controller. This enables periodic calibration of the winding temperature controller, ensuring effective control over the measurement accuracy without power interruption. It effectively monitors the measurement accuracy during the winding temperature controller's operation, ensuring that the winding temperature controller is in a normal operating state and providing accurate and effective winding temperature measurements. Attached Figure Description

[0048] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art 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.

[0049] Figure 1 This is a flowchart illustrating the steps of a transformer winding temperature controller calibration method provided in Embodiment 1 of the present invention.

[0050] Figure 2 This is a flowchart illustrating the steps of a transformer winding temperature controller calibration method provided in Embodiment 2 of the present invention.

[0051] Figure 3 The heating current versus additional temperature rise fitting curve provided for embodiments of the present invention;

[0052] Figure 4 This is a structural block diagram of a transformer winding temperature controller calibration system provided in Embodiment 3 of the present invention. Detailed Implementation

[0053] This invention provides a method, system, equipment, and medium for calibrating transformer winding temperature controllers. It addresses the technical problem of long calibration cycles for winding temperature controllers, lack of effective periodic control over the controllers, monitoring the accuracy of winding temperature controller measurements, and ensuring accurate temperature measurements are provided during transformer operation.

[0054] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0055] Please see Figure 1 , Figure 1 The flowchart illustrates the steps of a transformer winding temperature controller calibration method provided in Embodiment 1 of the present invention.

[0056] The present invention provides a method for calibrating a transformer winding temperature controller, comprising the following steps:

[0057] Step 101: Respond to the winding temperature controller calibration request and collect the target transformer winding temperature measurement value, transformer main load current and transformer oil temperature of multiple winding temperature controllers within the preset calibration period.

[0058] A winding temperature controller is a pressure instrument that has electrical nodes and remote signal transmission devices, uses thermal simulation technology to display the temperature of transformer windings, and outputs control signals and remote signals.

[0059] A winding temperature controller calibration request refers to a calibration request message sent to check whether the winding temperature controller is operating normally.

[0060] Transformer oil temperature refers to the temperature of the top layer of oil in the transformer. Specifically, the transformer oil temperature can be measured using an oil level thermometer or a resistance temperature detector (RTD) installed on the transformer.

[0061] The preset calibration cycle refers to the time period set during the operation of the winding temperature controller, during which the winding temperature controller is calibrated.

[0062] It should be noted that within the preset calibration period, there are multiple time intervals. Data is collected at these multiple time intervals, including the target transformer winding temperature measurement value, the transformer main load current, and the transformer oil temperature corresponding to each time interval.

[0063] In this embodiment of the invention, the target transformer winding temperature measurement value, the main transformer load current and the transformer oil temperature are collected at each time interval within a preset calibration period for the winding temperature controller to calibrate the winding temperature controller. Through periodic calibration, the operating status of the winding temperature controller during operation can be calibrated, and the winding temperature controller can be effectively controlled during operation.

[0064] Step 102: Input multiple main transformer load currents into the preset target winding temperature controller temperature rise function to obtain the copper oil temperature difference value corresponding to the main transformer load current.

[0065] The preset target winding temperature rise function refers to the functional relationship with the main transformer load current as the variable and the copper oil temperature difference of the winding temperature controller as the target value.

[0066] The copper-oil temperature difference refers to the temperature difference between the transformer windings and the transformer oil.

[0067] In this embodiment of the invention, by inputting the main transformer load current corresponding to each time interval point into the preset target winding temperature controller temperature rise function, the copper oil temperature difference value corresponding to the main transformer load current at each time interval point within the preset verification period can be calculated. Only by collecting the main transformer load current can the corresponding copper oil temperature difference value be calculated.

[0068] Step 103: Calculate the sum of the transformer oil temperature and the copper oil temperature difference to obtain the theoretical values ​​of the winding temperature of multiple target transformers.

[0069] Transformer winding temperature refers to the sum of the top layer oil temperature and the temperature rise of the winding relative to the oil (i.e., the sum of the difference between the transformer oil temperature and the copper oil temperature).

[0070] The theoretical value of the target transformer winding temperature refers to the sum of the collected transformer top oil temperature and the copper oil temperature difference calculated theoretically using the temperature rise function of the target winding temperature controller.

[0071] In this embodiment of the invention, by calculating the sum of the transformer oil temperature and the copper oil temperature difference within a preset calibration period, multiple theoretical values ​​of target transformer winding temperature are obtained for comparison with the measured values.

[0072] Step 104: Calculate the temperature difference between the measured value of the target transformer winding temperature and the theoretical value of the target transformer winding temperature, and obtain the accuracy error values ​​of multiple winding temperature controllers.

[0073] The target transformer winding temperature measurement value refers to the actual transformer winding temperature detected by the winding temperature controller installed on the transformer.

[0074] In this embodiment of the invention, by calculating the temperature difference between the measured value and the theoretical value of the target transformer winding temperature, the accuracy error value of the winding temperature controller at each time interval within the preset calibration period is obtained, that is, the deviation between the actual measured value and the theoretical value is obtained. The accuracy error value of the winding temperature controller can be used as a basis for judgment, which has good reference significance for determining whether the winding temperature controller is normal within the calibration period.

[0075] Step 105: Compare the accuracy error value of the winding temperature controller with the preset accuracy error threshold of the winding temperature controller, and output the operating status of the winding temperature controller based on the comparison result.

[0076] It should be noted that within the preset calibration period, multiple accuracy error values ​​of the winding temperature controller were calculated. Among these multiple accuracy error values, the maximum value is more meaningful for reference. If the maximum value meets the preset accuracy error threshold, the other accuracy error values ​​also meet the condition. If the maximum value does not meet the condition, then at least one of the multiple accuracy error values ​​must not meet the condition when compared with the accuracy error threshold.

[0077] In this embodiment of the invention, by comparing the accuracy error value of the winding temperature controller with a preset accuracy error threshold of the winding temperature controller, wherein the maximum value of the accuracy error value of the winding temperature controller is selected and compared with the preset accuracy error threshold of the winding temperature controller, the operating status of the winding temperature controller can be determined based on the comparison result, and the operating status of the winding temperature controller is output.

[0078] In practical implementation, the maximum value of the winding temperature controller's accuracy error is compared with the preset winding temperature controller accuracy error threshold. If the winding temperature controller's accuracy error exceeds the preset threshold, the operating status of the output winding temperature controller is abnormal. If the winding temperature controller's accuracy error is less than or equal to the preset threshold, the operating status of the output winding temperature controller is normal. The operating status of the output winding temperature controller can be used to determine whether a pre-power-off test of the winding temperature controller is required.

[0079] In this embodiment of the invention, in response to the winding temperature controller calibration request, the measured values ​​of the target transformer winding temperature, the main transformer load current, and the transformer oil temperature are collected within a preset calibration period. Then, the multiple main transformer load currents are respectively input into the preset target winding temperature controller temperature rise function to obtain the copper-oil temperature difference value corresponding to the main transformer load current. The copper-oil temperature difference value is calculated by collecting the main transformer load current. Then, the sum of the transformer oil temperature and the copper-oil temperature difference value is calculated to obtain the theoretical values ​​of the target transformer winding temperature. Then, the temperature difference between the measured value of the target transformer winding temperature and the theoretical value of the target transformer winding temperature is calculated to obtain the accuracy error value of the multiple winding temperature controllers. Finally, the accuracy error value of the winding temperature controller is compared with the preset accuracy error threshold of the winding temperature controller, and the operating status of the winding temperature controller is output based on the comparison result. This invention periodically calculates the accuracy error value of the winding temperature controller during operation and compares it with a preset accuracy error threshold to determine the operating status of the winding temperature controller. This enables periodic calibration of the winding temperature controller, ensuring effective control over the measurement accuracy without power interruption. It effectively monitors the measurement accuracy during the winding temperature controller's operation, ensuring that the winding temperature controller is in a normal operating state and providing accurate and effective winding temperature measurements.

[0080] Please see Figure 2 , Figure 2 This is a flowchart illustrating the steps of a transformer winding temperature controller calibration method provided in Embodiment 2 of the present invention.

[0081] This invention provides a method for calibrating a transformer winding temperature controller, comprising the following steps:

[0082] Step 201: Respond to the winding temperature controller calibration request and collect the target transformer winding temperature measurement value, transformer main load current and transformer oil temperature of multiple winding temperature controllers within the preset calibration period.

[0083] In this embodiment of the invention, the specific implementation process of step 201 is similar to that of step 101, and will not be repeated here.

[0084] Step 202: Respond to the copper oil temperature difference detection request and obtain the transformer fixed parameter information and the winding temperature controller fixed parameter information.

[0085] In this embodiment of the invention, by obtaining the fixed parameter information of the transformer and the fixed parameter information of the winding temperature controller, and combining them with the corresponding functional relationships, it is convenient to calculate the remaining parameters to construct the heating current calculation function.

[0086] Step 203: Construct a heating current calculation function with the main transformer load current as the variable using the transformer fixed parameter information and the winding temperature controller fixed parameter information.

[0087] Optionally, the transformer fixed parameters include the transformer rated capacity, transformer rated voltage, temperature sensing winding CT ratio, and transformer rated copper oil temperature difference. The winding temperature controller fixed parameters include the rated heating current corresponding to the transformer rated copper oil temperature difference. Step 203 may include the following sub-steps S11-S14:

[0088] Step S11: Input the transformer's rated capacity and rated voltage into the preset transformer current calculation formula to obtain the transformer's rated current.

[0089] In practical implementation, the preset formula for calculating transformer current is:

[0090]

[0091] Where I 额定 S is the rated current of the transformer, S is the rated capacity of the transformer, and V is the rated voltage of the transformer.

[0092] Step S12: Calculate the first ratio of the transformer rated current to the CT ratio of the temperature measuring winding to obtain the winding temperature controller matching current.

[0093] In practical implementation, the formula for calculating the matching current of the winding temperature controller is:

[0094] Ip 额定 =I 额定 / K

[0095] Among them Ip 额定 K is the winding temperature controller matching current corresponding to the transformer's rated current, and K is the CT ratio of the temperature sensing winding.

[0096] Step S13: Calculate the second ratio of the rated heating current to the winding temperature controller matching current to obtain the winding temperature controller matching ratio.

[0097] In practical implementation, the formula for calculating the turns ratio of the winding temperature controller matching unit is:

[0098] K p =Is 额定 / Ip 额定

[0099] Where K p For the winding temperature controller matching ratio, Is 额定 This is the rated heating current.

[0100] Step S14: Using the winding temperature controller matching ratio and the temperature measuring winding CT ratio, construct a function to calculate the heating current with the main transformer load current as the variable.

[0101] In the specific implementation, based on the simultaneous solution of the formulas in steps S12 and S13, and using the winding temperature controller matching ratio and the temperature sensing winding CT ratio, the heating current calculation function is constructed with the main transformer load current as the variable:

[0102] Is = I / K*K p

[0103] Where Is is the heating current and I is the main transformer load current.

[0104] In this embodiment of the invention, specific calculation formulas are used to solve for the corresponding related variables, such as the winding temperature controller matching current and the winding temperature controller matching ratio. At the same time, the calculation formulas can be used to obtain the functional relationship between each transformer fixed parameter and the winding temperature controller fixed parameter. Based on the functional relationship corresponding to each functional relationship, the heating current calculation function can be constructed, that is, the functional relationship between the heating current and the main transformer load current.

[0105] Step 204: Substitute the heating current calculation function into the preset winding temperature controller temperature rise function to obtain the target winding temperature controller temperature rise function corresponding to the main transformer load current.

[0106] The temperature rise function of the winding temperature controller refers to the calculation function with heating current as the variable and additional temperature rise as the target value. It is a functional relationship between heating current and additional temperature rise.

[0107] It should be noted that different winding temperature controllers correspond to different winding temperature rise functions, which can be expressed as ΔT = f(Is) or ΔT = f(I / K*K). p The temperature rise function of the winding temperature controller can be obtained by curve fitting based on a preset data table, which includes the heating current and the additional temperature rise corresponding to the heating current.

[0108] For example, in a specific implementation, if the preset data table for the winding temperature controller that needs to be calibrated is Table 1, where Table 1 is the temperature difference data table for the copper oil of the 12.15.18 type temperature bulb, Table 1 is as follows:

[0109] Table 1

[0110] In specific implementation, the heating current and additional temperature rise data in the copper oil temperature difference data table of the 12.15.18 type heating bulb are used. Preferably, this embodiment supplements a set of data passing through the origin to improve the smoothness and accuracy of the fitted curve. The heating current is used as the independent variable, and the additional temperature rise is used as the dependent variable. A cubic polynomial equation is used as the fitted curve, and curve fitting is performed using the least squares method. Optionally, the heating current and additional temperature rise data can be entered into an Excel spreadsheet, and the fitting can be performed using a cubic polynomial in the trend line using charting tools, such as... Figure 3 As shown, Figure 3 To fit the heating current and the additional temperature rise curve, the corresponding winding temperature controller temperature rise function is obtained through fitting:

[0111] ΔT = -4.2Is 3 +23.717Is 2 -0.9781Is

[0112] Where ΔT is the additional temperature rise, i.e. the temperature difference between copper and oil, and Is is the heating current.

[0113] The coefficient of determination R of the corresponding winding temperature controller temperature rise function 2 =0.9999, representing the correlation between heating current and additional temperature rise, where R 2 The closer to 1, the better the fit.

[0114] In this embodiment of the invention, the heating current calculation function is specifically a functional relationship between the heating current and the main transformer load current. By substituting the heating current calculation function into the preset winding temperature controller temperature rise function, the winding temperature controller temperature rise function with heating current as the variable is equivalently replaced with the target winding temperature controller temperature rise function with the main transformer load current as the variable. By solving for the additional temperature rise, i.e. the copper-oil temperature difference, with the main transformer load current as the variable, the winding temperature controller can be calibrated simply by detecting the main transformer load current, reducing the amount of data collection, reducing the amount of calculation, and improving the accuracy of the calibration.

[0115] Step 205: Input multiple main transformer load currents into the preset target winding temperature controller temperature rise function to obtain the copper oil temperature difference value corresponding to the main transformer load current.

[0116] In this embodiment of the invention, the specific implementation process of step 205 is similar to that of step 102, and will not be repeated here.

[0117] Step 206: Calculate the sum of the transformer oil temperature and the copper oil temperature difference to obtain the theoretical values ​​of multiple target transformer winding temperatures.

[0118] In practical implementation, the formula for calculating the sum of the transformer oil temperature and copper oil temperature difference is:

[0119] T绕计算 =T 油 +ΔT

[0120] Among them, T 绕计算 T represents the theoretical value of the target transformer winding temperature. 油 ΔT represents the transformer oil temperature, and ΔT represents the copper oil temperature difference (additional temperature rise).

[0121] In this embodiment of the invention, by calculating the sum of the transformer oil temperature and the copper oil temperature difference within a preset calibration period, multiple theoretical values ​​of target transformer winding temperature are obtained for comparison with the measured values.

[0122] Step 207: Calculate the temperature difference between the measured value of the target transformer winding temperature and the theoretical value of the target transformer winding temperature, and obtain the accuracy error values ​​of multiple winding temperature controllers.

[0123] In practical implementation, the formula for calculating the temperature difference between the measured temperature of the target transformer winding and the theoretical temperature of the target transformer winding is as follows:

[0124] E=T 绕 -T 绕计算

[0125] Where E is the accuracy error value of the winding temperature controller, and T 绕 The measured value is the winding temperature of the target transformer.

[0126] In this embodiment of the invention, by calculating the temperature difference between the measured value and the theoretical value of the target transformer winding temperature, the accuracy error value of the winding temperature controller at each time interval within the preset calibration period is obtained, that is, the deviation between the actual measured value and the theoretical value is obtained. The accuracy error value of the winding temperature controller can be used as a basis for judgment, which has good reference significance for determining whether the winding temperature controller is normal within the calibration period.

[0127] Step 208: Compare the accuracy error value of the winding temperature controller with the preset accuracy error threshold of the winding temperature controller, and output the operating status of the winding temperature controller based on the comparison result.

[0128] Optionally, step 208 includes the following sub-steps:

[0129] Select a target percentage probability value from multiple winding temperature controller accuracy error values, and compare the winding temperature controller accuracy error value corresponding to the target percentage probability value with the preset winding temperature controller accuracy error threshold.

[0130] If the accuracy error value of the winding temperature controller is greater than the preset accuracy error threshold of the winding temperature controller, the operating status of the output winding temperature controller will be abnormal.

[0131] If the accuracy error value of the winding temperature controller is less than or equal to the preset accuracy error threshold of the winding temperature controller, then the operating status of the output winding temperature controller is normal.

[0132] The target percentage probability value refers to the maximum value among all winding temperature controller accuracy error values ​​that falls within the target percentage range, selected by sorting all winding temperature controller accuracy error values ​​by size.

[0133] It should be noted that the target percentage probability value can be selected as 95% probability value. 95% probability value means that the sampled points are arranged in descending order, the 5% maximum value is removed, and the winding temperature controller accuracy error value corresponding to the maximum value among the remaining sampled points is the 95% probability value.

[0134] In this embodiment of the invention, by selecting a 95% probability value from multiple winding temperature controller accuracy error values, the winding temperature controller accuracy error value corresponding to the 95% probability value is compared with a preset winding temperature controller accuracy error threshold. This eliminates calibration errors that occur during the calibration process, improving the accuracy of winding temperature controller calibration. If the winding temperature controller accuracy error value is greater than the winding temperature controller accuracy error threshold, the operating status of the winding temperature controller is output as abnormal. In this calibration cycle, the measurement accuracy of the winding temperature controller is abnormal, requiring a power outage for further calibration to ensure timely accuracy of the winding temperature controller measurement, providing accurate transformer winding temperature and improving the accuracy of transformer winding temperature detection. If the winding temperature controller accuracy error value is less than or equal to the winding temperature controller accuracy error threshold, the operating status of the winding temperature controller is output as normal. In this case, the winding temperature controller can provide accurate measurement values ​​during operation without requiring a power outage for calibration, providing effective period control during the operation of the winding temperature controller.

[0135] In practical implementation, for example, a transformer has a rated capacity S = 50000 MVA, a rated voltage V = 110 kV, a temperature sensing winding CT ratio k = 300 / 5, and a rated copper oil temperature difference ΔT. 额定 =20k, the rated heating current Is corresponding to the rated copper oil temperature difference of the transformer. 额定 =1.03A, the winding temperature controller accuracy error threshold is 3℃, the preset verification cycle is 1 day, the time interval is 15 minutes, and the preset winding temperature controller accuracy error threshold is 2δ, where δ = 3℃, and δ represents the winding temperature controller accuracy error limit. Then, the verification process of the winding temperature controller during the operation of this transformer is as follows:

[0136] First, the rated current of the temperature sensing winding CT ratio under full transformer load is calculated using the preset transformer current calculation formula.

[0137]

[0138] Secondly, the current of the winding temperature controller matching device is calculated using the formula for calculating the current of the winding temperature controller matching device:

[0139] Ip 额定 =I 额定 / K=262.43 / (300 / 5)=4.37A

[0140] Next, the winding temperature controller matching ratio is calculated using the formula:

[0141] K p =Is 额定 / Ip 额定 =1.03 / 4.37 = 0.235489628

[0142] Then, based on the heating current calculation function, the functional relationship between the heating current and the main transformer load current is obtained as follows:

[0143] Is = I / K*K p =I / 60*0.235489628

[0144] Finally, substituting the heating current calculation function into the preset winding temperature controller temperature rise function, the target winding temperature controller temperature rise function corresponding to the main transformer load current is obtained as follows:

[0145] ΔT=f(I / 60*0.235489628)

[0146] The data obtained by using the above verification method is shown in Table 2. Table 2 is a data table of accuracy error values ​​for the winding temperature controller. Table 2 is as follows:

[0147]

[0148]

[0149]

[0150] Table 2

[0151] Next, the winding temperature controller accuracy error values ​​are sorted in the data table according to the absolute value of the winding temperature controller accuracy error value. The winding temperature controller accuracy error value corresponding to the 95% probability value is selected as 1.322678165≈1.32, which is less than 2*|±3|=6. Therefore, it is determined that the winding temperature controller error of the substation is within the allowable range within this calibration period, and the operating status is normal.

[0152] In this embodiment of the invention, firstly, in response to the winding temperature controller calibration request, the target transformer winding temperature measurement values, the transformer main load current, and the transformer oil temperature are collected within a preset calibration period. Secondly, in response to the copper oil temperature difference detection request, transformer fixed parameter information and winding temperature controller fixed parameter information are obtained. Then, a heating current calculation function with the main transformer load current as the variable is constructed using the transformer fixed parameter information and the winding temperature controller fixed parameter information. Then, the heating current calculation function is substituted into the preset winding temperature controller temperature rise function to obtain the target winding temperature controller temperature rise function corresponding to the main transformer load current. Finally, multiple main transformer load currents are input to the preset target... The winding temperature controller temperature rise function is used to obtain the copper oil temperature difference value corresponding to the main transformer load current. Then, the sum of the transformer oil temperature and the copper oil temperature difference value is calculated to obtain multiple theoretical values ​​of the target transformer winding temperature. In addition, the temperature difference between the measured value of the target transformer winding temperature and the theoretical value of the target transformer winding temperature is calculated to obtain multiple winding temperature controller accuracy error values. Finally, the winding temperature controller accuracy error value is compared with the preset winding temperature controller accuracy error threshold. Based on the comparison results, the operating status of the winding temperature controller is output. Among them, the 95% probability value of the multiple winding temperature controller accuracy error values ​​is compared with the preset winding temperature controller accuracy error threshold to improve the accuracy and precision of the verification. Specifically, this invention constructs a functional relationship between the main transformer load current and the heating current, i.e., a heating current calculation function. Simultaneously, based on this heating current calculation function, the winding temperature rise function, which uses the heating current as a variable, is equivalently replaced with a target winding temperature rise function, which uses the main transformer load current as a variable. By collecting the main transformer load current, the winding temperature controller is calibrated, reducing the computational load and improving calibration accuracy and efficiency. Furthermore, by calculating multiple winding temperature controller accuracy error values ​​within the calibration period and comparing them using 95% probability values, the accuracy of the calibration is improved. This enables periodic calibration of the winding temperature controller, ensuring effective control over the accuracy of winding temperature controller measurements without power interruption. It effectively monitors the accuracy of measurements during the winding temperature controller's operation, ensuring the winding temperature controller operates normally and provides accurate and effective winding temperature measurements.

[0153] Please see Figure 4 , Figure 4 This is a structural block diagram of a transformer winding temperature controller calibration system provided in Embodiment 3 of the present invention.

[0154] This invention provides a transformer winding temperature controller calibration system, comprising:

[0155] The parameter acquisition module 301 is used to respond to the winding temperature controller calibration request and acquire the target transformer winding temperature measurement value, transformer main load current and transformer oil temperature of multiple winding temperature controllers within a preset calibration period.

[0156] The copper oil temperature difference calculation module 302 is used to input multiple main transformer load currents into the preset target winding temperature controller temperature rise function to obtain the copper oil temperature difference value corresponding to the main transformer load current.

[0157] The target transformer winding temperature theoretical value calculation module 303 is used to calculate the sum of the transformer oil temperature and the copper oil temperature difference to obtain multiple target transformer winding temperature theoretical values.

[0158] The winding temperature controller accuracy error value calculation module 304 is used to calculate the temperature difference between the measured value of the target transformer winding temperature and the theoretical value of the target transformer winding temperature, and obtain multiple winding temperature controller accuracy error values.

[0159] The verification and judgment module 305 is used to compare the accuracy error value of the winding temperature controller with the preset accuracy error threshold of the winding temperature controller, and output the operating status of the winding temperature controller based on the comparison result.

[0160] Optionally, the system also includes:

[0161] The fixed parameter acquisition module is used to respond to copper oil temperature difference detection requests and acquire transformer fixed parameter information and winding temperature controller fixed parameter information;

[0162] The heating current calculation function construction module is used to construct a heating current calculation function with the main transformer load current as the variable, using fixed parameter information of the transformer and fixed parameter information of the winding temperature controller.

[0163] The target winding temperature controller temperature rise function construction module is used to substitute the heating current calculation function into the preset winding temperature controller temperature rise function to obtain the target winding temperature controller temperature rise function corresponding to the main transformer load current.

[0164] Optionally, the transformer's fixed parameters include the transformer's rated capacity, rated transformer voltage, temperature sensing winding CT ratio, and rated copper oil temperature difference. The winding temperature controller's fixed parameters include the rated heating current corresponding to the transformer's rated copper oil temperature difference. The heating current calculation function construction module includes:

[0165] The transformer rated current calculation submodule is used to obtain the transformer rated current by inputting the transformer rated capacity and transformer rated voltage into the preset transformer current calculation formula;

[0166] The winding temperature controller matching current calculation submodule is used to calculate the first ratio between the transformer rated current and the CT ratio of the temperature measuring winding to obtain the winding temperature controller matching current.

[0167] The winding temperature controller matching ratio calculation submodule is used to calculate the second ratio between the rated heating current and the winding temperature controller matching current to obtain the winding temperature controller matching ratio.

[0168] The heating current calculation function construction submodule is used to construct the heating current calculation function by using the winding temperature controller matching ratio and the temperature measuring winding CT ratio, with the main transformer load current as the variable.

[0169] Optionally, the verification and judgment module includes:

[0170] The difference selection submodule is used to select a target percentage probability value among multiple winding temperature controller accuracy error values, and compare the winding temperature controller accuracy error value corresponding to the target percentage probability value with a preset winding temperature controller accuracy error threshold.

[0171] The first operating status output submodule is used to output that the operating status of the winding temperature controller is abnormal if the accuracy error value of the winding temperature controller is greater than the accuracy error threshold of the winding temperature controller.

[0172] The second operating status output submodule is used to output that the operating status of the winding temperature controller is normal if the accuracy error value of the winding temperature controller is less than or equal to the accuracy error threshold of the winding temperature controller.

[0173] In this embodiment of the invention, the parameter acquisition module 301 responds to the winding temperature controller calibration request and acquires the target transformer winding temperature measurement values, transformer main load current, and transformer oil temperature of multiple winding temperature controllers within a preset calibration period. Then, the copper-oil temperature difference calculation module 302 inputs the multiple main transformer load currents into the preset target winding temperature controller temperature rise function to obtain the copper-oil temperature difference value corresponding to the main transformer load current. The copper-oil temperature difference value is calculated by acquiring the main transformer load current. Then, the target transformer winding temperature theoretical value calculation module 303 calculates the sum of the transformer oil temperature and the copper-oil temperature difference value to obtain the theoretical values ​​of multiple target transformer winding temperatures. Then, the winding temperature controller accuracy error value calculation module 304 calculates the temperature difference between the target transformer winding temperature measurement value and the target transformer winding temperature theoretical value to obtain the accuracy error values ​​of multiple winding temperature controllers. Finally, the calibration judgment module 305 compares the winding temperature controller accuracy error value with the preset winding temperature controller accuracy error threshold and outputs the operating status of the winding temperature controller based on the comparison result. This invention periodically calculates the accuracy error value of the winding temperature controller during operation and compares it with a preset accuracy error threshold to determine the operating status of the winding temperature controller. This enables periodic calibration of the winding temperature controller, ensuring effective control over the measurement accuracy without power interruption. It effectively monitors the measurement accuracy during the winding temperature controller's operation, ensuring that the winding temperature controller is in a normal operating state and providing accurate and effective winding temperature measurements.

[0174] This invention provides an electronic device, including a memory and a processor. The memory stores a computer program, and when the computer program is executed by the processor, the processor performs the steps of the transformer winding temperature controller verification method as described in any embodiment of this invention.

[0175] This invention provides a computer-readable storage medium storing a computer program thereon, which, when executed, implements a transformer winding temperature controller calibration method as described in any embodiment of this invention.

[0176] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working process of the system and modules described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0177] In the several embodiments provided in this application, it should be understood that the disclosed systems and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0178] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0179] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0180] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0181] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method of calibrating a transformer winding temperature controller, characterized by, The method comprises the steps of: in response to the winding temperature controller calibration request, collecting the target transformer winding temperature measurement value of the winding temperature controller, the main transformer load current of the transformer and the transformer oil temperature within the preset calibration period; inputting the plurality of main transformer load currents into the preset target winding temperature controller temperature rise function respectively to obtain the copper oil temperature difference value corresponding to the main transformer load current respectively; calculating the sum of the transformer oil temperature and the copper oil temperature difference value respectively to obtain a plurality of target transformer winding temperature theoretical values; calculating the temperature difference value of the target transformer winding temperature measurement value and the target transformer winding temperature theoretical value respectively to obtain a plurality of winding temperature controller accuracy error values; comparing the winding temperature controller accuracy error value with the preset winding temperature controller accuracy error threshold value, and outputting the running state of the winding temperature controller based on the comparison result.

2. The transformer winding temperature controller verification method of claim 1, wherein, Before the step of inputting the plurality of main transformer load currents into the preset target winding temperature controller temperature rise function respectively to obtain the copper oil temperature difference value corresponding to the main transformer load current respectively, the method comprises the steps of: in response to the copper oil temperature difference value detection request, obtaining the transformer fixed parameter information and the winding temperature controller fixed parameter information; using the transformer fixed parameter information and the winding temperature controller fixed parameter information to construct a heating current calculation function with the main transformer load current as the variable; substituting the heating current calculation function into the preset winding temperature controller temperature rise function to obtain the target winding temperature controller temperature rise function corresponding to the main transformer load current.

3. The transformer winding temperature controller verification method of claim 2, wherein, The transformer fixed parameters include the transformer rated capacity, the transformer rated voltage, the temperature measurement winding CT transformation ratio, and the transformer rated copper oil temperature difference. The winding temperature controller fixed parameters include the rated heating current corresponding to the transformer rated copper oil temperature difference. The step of using the transformer fixed parameter information and the winding temperature controller fixed parameter information to construct a heating current calculation function with the main transformer load current as the variable comprises the steps of: using the transformer rated capacity and the transformer rated voltage as inputs into a preset transformer current calculation formula to obtain a transformer rated current; calculating the first ratio of the transformer rated current and the temperature measurement winding CT transformation ratio to obtain a winding temperature controller adapter current; calculating the second ratio of the rated heating current and the winding temperature controller adapter current to obtain a winding temperature controller adapter transformation ratio; using the winding temperature controller adapter transformation ratio and the temperature measurement winding CT transformation ratio to construct a heating current calculation function with the main transformer load current as the variable.

4. The transformer winding temperature controller verification method of claim 1, wherein, The step of comparing the winding temperature controller accuracy error value with the preset winding temperature controller accuracy error threshold value based on the comparison result to output the running state of the winding temperature controller comprises the steps of: selecting a target percentage probability value from the plurality of winding temperature controller accuracy error values, comparing the winding temperature controller accuracy error value corresponding to the target percentage probability value with the preset winding temperature controller accuracy error threshold value; if the winding temperature controller accuracy error value is greater than the winding temperature controller accuracy error threshold value, the running state of the winding temperature controller is abnormal. If the winding temperature controller accuracy error value is less than or equal to the winding temperature controller accuracy error threshold value, the running state of the winding temperature controller is output as normal; The target percentage probability value refers to sorting all winding temperature controller accuracy error values in size, and selecting the maximum value of all winding temperature controller accuracy error values within the target percentage range.

5. A transformer winding temperature controller verification system, characterized by, Comprise: The parameter acquisition module is used for collecting target transformer winding temperature measurement values, transformer main transformer load current and transformer oil temperature of a plurality of winding temperature controllers in a preset calibration period in response to a winding temperature controller calibration request; The copper oil temperature difference value calculation module is used for inputting a plurality of main transformer load currents into a preset target winding temperature controller temperature rise function respectively, and obtaining copper oil temperature difference values corresponding to the main transformer load currents respectively; The target transformer winding temperature theoretical value calculation module is used for calculating the sum of the transformer oil temperature and the copper oil temperature difference value respectively, and obtaining a plurality of target transformer winding temperature theoretical values; The winding temperature controller accuracy error value calculation module is used for calculating the temperature difference between the target transformer winding temperature measurement value and the target transformer winding temperature theoretical value respectively, and obtaining a plurality of winding temperature controller accuracy error values; The calibration judgment module is used for comparing the winding temperature controller accuracy error value with the preset winding temperature controller accuracy error threshold value, and outputting the running state of the winding temperature controller based on the comparison result.

6. The transformer winding temperature controller verification system of claim 5, wherein, Further comprise: The fixed parameter acquisition module is used for acquiring transformer fixed parameter information and winding temperature controller fixed parameter information in response to a copper oil temperature difference value detection request; The heating current calculation function construction module is used for constructing a heating current calculation function with the main transformer load current as a variable by using the transformer fixed parameter information and the winding temperature controller fixed parameter information; The target winding temperature controller temperature rise function construction module is used for substituting the heating current calculation function into a preset winding temperature controller temperature rise function, and obtaining a target winding temperature controller temperature rise function corresponding to the main transformer load current.

7. The transformer winding temperature controller verification system of claim 6, wherein, The transformer fixed parameters include transformer rated capacity, transformer rated voltage, temperature measuring winding CT transformation ratio, and transformer rated copper oil temperature difference, the winding temperature controller fixed parameters include a rated heating current corresponding to the transformer rated copper oil temperature difference, and the heating current calculation function construction module comprises: The transformer rated current calculation submodule is used for inputting the transformer rated capacity and the transformer rated voltage into a preset transformer current calculation formula, and obtaining a transformer rated current; The winding temperature controller matcher current calculation submodule is used for calculating a first ratio of the transformer rated current to the temperature measuring winding CT transformation ratio, and obtaining a winding temperature controller matcher current; The winding temperature controller matcher transformation ratio calculation submodule is used for calculating a second ratio of the rated heating current to the winding temperature controller matcher current, and obtaining a winding temperature controller matcher transformation ratio; The heating current calculation function construction submodule is used for constructing a heating current calculation function with the main transformer load current as a variable by using the winding temperature controller matcher transformation ratio and the temperature measuring winding CT transformation ratio.

8. The transformer winding temperature controller verification system of claim 5, wherein, The calibration judgment module comprises: The difference selection submodule is configured to select a target percentage probability value from the plurality of winding temperature controller accuracy error values, compare a winding temperature controller accuracy error value corresponding to the target percentage probability value with a preset winding temperature controller accuracy error threshold value, and output a running state of the winding temperature controller. The first running state output submodule is configured to output that the running state of the winding temperature controller is abnormal if the winding temperature controller accuracy error value is greater than the winding temperature controller accuracy error threshold value. The second running state output submodule is configured to output that the running state of the winding temperature controller is normal if the winding temperature controller accuracy error value is less than or equal to the winding temperature controller accuracy error threshold value. The target percentage probability value refers to selecting a maximum value in a target percentage range from all winding temperature controller accuracy error values in size order.

9. An electronic device, comprising: The computer program is stored in the memory and is executed by the processor, so that the processor executes the steps of the transformer winding temperature controller calibration method according to any one of claims 1-4.

10. A computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed to implement the transformer winding temperature controller calibration method according to any one of claims 1-4.

Images