Capacitive voltage transformer dielectric loss measurement error correction method and device

Abstract

The application relates to a dielectric loss measurement error correction method and device for a capacitive voltage transformer. The method comprises the following steps: constructing a dielectric loss measurement equivalent analysis circuit based on a dielectric loss equivalent circuit as a target circuit model; the target circuit model is used for quantitatively calculating dielectric loss test data of the capacitive voltage transformer under the influence of an interference branch; obtaining a target expression set corresponding to the target circuit model, and obtaining a first dielectric loss value and a first capacitance parameter corresponding to an electromagnetic unit in the capacitive voltage transformer according to the target expression set; determining a dielectric loss measurement correction result as corrected dielectric loss data corresponding to a capacitance divider in the capacitive voltage transformer according to test current parameter information measured under preset test conditions, the first dielectric loss value and the first capacitance parameter. The method can correct the dielectric loss measurement error of the capacitive voltage transformer, and improves the dielectric loss measurement accuracy of the capacitive voltage transformer.

Description

Technical Field

[0001] This application relates to the field of power technology, and in particular to a method, apparatus, computer equipment, storage medium and computer program product for correcting the measurement error of dielectric loss of a capacitive voltage transformer. Background Technology

[0002] The dielectric loss and capacitance test of the capacitive voltage divider of a capacitive voltage transformer (CVT) is an important test item for capacitive voltage transformer equipment. It can detect whether there are defects such as moisture or deterioration in the capacitor insulation, as well as whether there are abnormal phenomena such as component breakdown or insufficient oil inside the capacitor.

[0003] Currently, traditional CVT dielectric loss measurement data error analysis methods only offer qualitative analysis and cannot perform quantitative calculations or error correction, addressing the issue of errors in experimental data during dielectric loss and capacitance testing. Errors in CVT capacitor voltage divider dielectric loss measurement data can affect experimental data analysis and judgment, potentially leading to misjudgments. Summary of the Invention

[0004] Therefore, it is necessary to provide a method, apparatus, computer equipment, storage medium, and computer program product for correcting the dielectric loss measurement error of a capacitive voltage transformer, which can solve the above-mentioned technical problems.

[0005] In a first aspect, this application provides a method for correcting the measurement error of dielectric loss in a capacitive voltage transformer, the method comprising:

[0006] An equivalent analysis circuit for dielectric loss measurement is constructed based on the dielectric loss equivalent circuit, serving as the target circuit model; the target circuit model is used to quantitatively calculate the dielectric loss test data of the capacitive voltage transformer under the influence of interference branches;

[0007] Obtain the set of target expressions corresponding to the target circuit model, and based on the set of target expressions, obtain the first dielectric loss value and the first capacitance parameter corresponding to the electromagnetic unit in the capacitive voltage transformer;

[0008] Based on the test current parameter information, the first dielectric loss value, and the first capacitance parameter obtained from the preset test conditions, the dielectric loss measurement correction result is determined and used as the corrected dielectric loss data corresponding to the capacitive voltage divider in the capacitive voltage transformer.

[0009] In one embodiment, the construction of the dielectric loss measurement equivalent analysis circuit based on the dielectric loss equivalent circuit, as the target circuit model, includes:

[0010] Based on the measurement mechanism of the digital automatic dielectric loss meter, an equivalent analysis circuit for dielectric loss measurement is constructed based on the dielectric loss equivalent circuit, which serves as the target circuit model.

[0011] The dielectric loss measurement equivalent analysis circuit is used as an equivalent circuit to characterize dielectric loss, and the dielectric loss data calculated based on the dielectric loss measurement equivalent analysis circuit is consistent with the dielectric loss data measured by the digital automatic dielectric loss meter.

[0012] In one embodiment, obtaining the set of target expressions corresponding to the target circuit model includes:

[0013] Based on the target circuit model, dielectric loss test data under the influence of interference branches are calculated, and the target expression set is formed based on the dielectric loss test data;

[0014] The target expression set is used to characterize the relationship between the second dielectric loss value and the second capacitance parameter corresponding to the capacitive voltage divider, the first dielectric loss value and the first capacitance parameter, and the dielectric loss measurement value.

[0015] In one embodiment, obtaining the first dielectric loss value and the first capacitance parameter corresponding to the electromagnetic unit in the capacitive voltage transformer based on the target expression set includes:

[0016] Based on the target expression set, the first dielectric loss value and the first capacitance parameter corresponding to the electromagnetic unit are obtained according to the preset test wiring method.

[0017] In one embodiment, obtaining the first dielectric loss value and the first capacitance parameter corresponding to the electromagnetic unit according to a preset test wiring method includes:

[0018] The measured dielectric loss value and measured capacitance parameter of the electromagnetic unit are obtained according to the preset test wiring method;

[0019] The measured capacitance parameters and the measured dielectric loss values ​​are corrected to obtain the first dielectric loss value and the first capacitance parameters corresponding to the electromagnetic unit.

[0020] In one embodiment, determining the dielectric loss measurement correction result based on the test current parameter information obtained from the preset test conditions, the first dielectric loss value, and the first capacitance parameter, as the corrected dielectric loss data corresponding to the capacitive voltage divider in the capacitive voltage transformer, includes:

[0021] According to the preset test conditions, the full current amplitude and power factor angle data are measured using the digital automatic dielectric loss meter and used as the test current parameter information;

[0022] The current vector parameters are obtained based on the test current parameter information;

[0023] By combining the current vector parameters, the first dielectric loss value, and the first capacitance parameters, the dielectric loss measurement correction result is determined and used as the corrected dielectric loss data corresponding to the capacitive voltage divider in the capacitive voltage transformer.

[0024] In one embodiment, determining the dielectric loss measurement correction result by combining the current vector parameter, the first dielectric loss value, and the first capacitance parameter, as the corrected dielectric loss data corresponding to the capacitive voltage divider in the capacitive voltage transformer, includes:

[0025] Based on the target expression set, the inverse function or system of equations is calculated and solved according to the current vector parameters, the first dielectric loss value, and the first capacitance parameters to obtain the dielectric loss measurement correction result, which is used as the corrected dielectric loss data corresponding to the capacitive voltage divider in the capacitive voltage transformer.

[0026] Secondly, this application also provides a device for correcting the dielectric loss measurement error of a capacitive voltage transformer, the device comprising:

[0027] The equivalent analysis circuit construction module is used to construct an equivalent analysis circuit for dielectric loss measurement based on the dielectric loss equivalent circuit, which serves as the target circuit model. The target circuit model is used to quantitatively calculate the dielectric loss test data of the capacitive voltage transformer under the influence of interference branches.

[0028] The dielectric loss data acquisition module is used to acquire the target expression set corresponding to the target circuit model, and obtain the first dielectric loss value and the first capacitance parameter corresponding to the electromagnetic unit in the capacitive voltage transformer based on the target expression set.

[0029] The error correction module is used to determine the dielectric loss measurement correction result based on the test current parameter information, the first dielectric loss value, and the first capacitance parameter obtained from the preset test conditions, and to use it as the corrected dielectric loss data corresponding to the capacitive voltage divider in the capacitive voltage transformer.

[0030] Thirdly, this application also provides a computer device. The computer device includes a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement the steps of the capacitive voltage transformer dielectric loss measurement error correction method as described above.

[0031] Fourthly, this application also provides a computer-readable storage medium. The computer-readable storage medium stores a computer program thereon, which, when executed by a processor, implements the steps of the capacitive voltage transformer dielectric loss measurement error correction method as described above.

[0032] Fifthly, this application also provides a computer program product. The computer program product includes a computer program that, when executed by a processor, implements the steps of the capacitive voltage transformer dielectric loss measurement error correction method as described above.

[0033] The aforementioned method, apparatus, computer equipment, storage medium, and computer program product for correcting dielectric loss measurement errors in capacitive voltage transformers utilize a dielectric loss equivalent analysis circuit constructed based on an equivalent dielectric loss circuit as a target circuit model. This target circuit model is used to quantitatively calculate the dielectric loss test data of the capacitive voltage transformer under the influence of interference branches. Then, a set of target expressions corresponding to the target circuit model is obtained. Based on this set of target expressions, the first dielectric loss value and the first capacitance parameter corresponding to the electromagnetic unit in the capacitive voltage transformer are obtained. Furthermore, based on the test current parameter information, the first dielectric loss value, and the first capacitance parameter measured under preset test conditions, the dielectric loss measurement correction result is determined as the corrected dielectric loss data corresponding to the capacitive voltage divider in the capacitive voltage transformer. This achieves quantitative calculation of the dielectric loss measurement error of the capacitive voltage transformer, enabling error correction and improving the accuracy of dielectric loss measurement. Attached Figure Description

[0034] Figure 1a This is a schematic diagram illustrating the electrical principle of a capacitive voltage transformer in one embodiment;

[0035] Figure 1b This is a schematic diagram of the principle and vector of the positive connection method for measuring equivalence in one embodiment;

[0036] Figure 2 This is a flowchart illustrating a method for correcting the dielectric loss measurement error of a capacitive voltage transformer in one embodiment.

[0037] Figure 3a This is a schematic diagram of an equivalent analysis circuit for dielectric loss measurement in one embodiment;

[0038] Figure 3b This is a schematic diagram of a parallel equivalent circuit and vector of a dielectric in one embodiment;

[0039] Figure 3c This is a schematic diagram illustrating the measurement principle of a digital automatic dielectric loss meter in one embodiment;

[0040] Figure 3d This is a schematic diagram illustrating the measurement principle of a digital automatic dielectric loss meter using the reverse connection method in one embodiment.

[0041] Figure 4a This is a schematic diagram of the equivalent circuit for a positive polarity measurement and analysis method in one embodiment;

[0042] Figure 4b This is a schematic diagram of an equivalent circuit for measuring dielectric loss of a CVT electromagnetic unit in one embodiment;

[0043] Figure 5 This is a flowchart illustrating another method for correcting the dielectric loss measurement error of a capacitive voltage transformer in one embodiment.

[0044] Figure 6 This is a structural block diagram of a capacitor voltage transformer dielectric loss measurement error correction device in one embodiment;

[0045] Figure 7 This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0047] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for display, data used for analysis, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties; correspondingly, this application also provides a corresponding user authorization entry point for users to choose to authorize or refuse.

[0048] A capacitive voltage transformer (CVT) is a type of voltage transformer that uses a capacitive voltage divider to divide the primary voltage into a lower intermediate voltage, which is then transformed into a secondary voltage by an intermediate transformer. A CVT mainly consists of a capacitive voltage divider and an electromagnetic unit, which also includes components such as an intermediate transformer and a compensating reactor. The electrical schematic diagram of a capacitive voltage transformer is shown below. Figure 1a As shown, C1 is the main capacitor; C2 is the voltage divider capacitor; D is the damper; N is the carrier communication terminal; T is the medium-voltage transformer; 1a-1n, 2a-2n, and da-dn are the secondary windings; L is the compensation reactor; X is the low-voltage terminal of the compensation reactor; A is the high-voltage terminal; and A′ is the medium-voltage terminal.

[0049] For capacitive voltage transformers (CVTs), since most CVTs are single-column structures, with the capacitor divider and electromagnetic unit stacked as a whole, a considerable number of CVTs have no lead-out structure at the intermediate transformer end (A′). In the process of conducting dielectric loss and capacitance tests on the capacitor dividers of such CVTs (e.g., 35kV~110kV: the whole section, 220kV and above: the next section; the CVT capacitor divider test in this application refers to this section), due to the influence of the CVT electromagnetic unit and the test principle and method, the test data all have certain errors. For example, the forward connection method produces a smaller error in measuring dielectric loss, the reverse connection method produces a larger error in measuring dielectric loss, the capacitance measurement produces a larger error, and the self-excited method produces a larger error in measuring dielectric loss.

[0050] For CVTs without lead-out structures at the first end (A′) of the intermediate transformer, there are three test methods for measuring the dielectric loss and capacitance of the capacitor divider: the positive connection method, the reverse connection method, and the self-excited method. All three methods have a certain degree of measurement error.

[0051] Under AC test voltage, the CVT electromagnetic unit and the terminal block at the end of the primary winding of the intermediate transformer (it should be noted that the components constituting the CVT interference branch include the electromagnetic unit and the terminal block at the end of the primary winding of the intermediate transformer, among which the electromagnetic unit is the most important component; for the sake of brevity, it is referred to as the electromagnetic unit in this application) form a loop with the CVT casing (ground). The loop current generates dielectric loss, and this loop enters the digital dielectric analyzer measurement circuit, forming an interference branch that affects the dielectric loss measurement results. This is a significant factor contributing to the error in the CVT capacitor voltage divider dielectric loss and capacitance tests. Due to the existence of this factor, unavoidable measurement errors are introduced into the CVT capacitor voltage divider dielectric loss test. Based on traditional CVT dielectric loss measurement data error analysis methods, only qualitative analysis of the measurement errors of the three CVT test wiring methods can be performed; quantitative calculation is not possible, making error correction difficult.

[0052] For example, a qualitative analysis of measurement errors based on three experimental methods:

[0053] (1) Direct Connection Method: The direct connection method measures the combined dielectric loss value of the voltage divider of capacitors C1 and C2. During the direct connection test, the CVT electromagnetic unit and the terminal block at the end of the primary winding of the intermediate transformer (referred to as the electromagnetic unit in this application) form a loop with the CVT casing (ground). This loop forms an interference branch to the test circuit. The equivalent principle diagram and vector diagram of the direct connection method measurement are as follows: Figure 1bAs shown, Z3 is the equivalent impedance of the electromagnetic interference branch, δ is the actual dielectric loss angle of the test specimen, and δ′ is the measured dielectric loss angle of the test specimen. Since the impedance of the interference branch is capacitive, the phase of voltage U2 will lead the phase of the power supply voltage, and the phase of current I2 will change accordingly, resulting in a measured dielectric loss value that is less than the actual value. The magnitude of the test error mainly depends on the magnitude of the current in the interference branch.

[0054] (2) Reverse connection method: The reverse connection method is used to measure the combined dielectric loss of the C1 and C2 capacitor voltage divider. During the test, the CVT electromagnetic unit is connected in parallel with the C2 part of the capacitor for measurement, which produces a larger error in the capacitance test data. The dielectric loss of the electromagnetic unit to the casing (ground) causes the dielectric loss measurement data to be larger. The degree of the larger error depends on the size of the dielectric loss of the electromagnetic unit to the casing (ground).

[0055] (3) Self-excitation method: The self-excitation method uses the medium-voltage transformer of the CVT as the test transformer. By applying voltage to the secondary winding side of the CVT to excite it, a high voltage is induced in the primary winding as the power source for measurement. The capacitance and dielectric loss of C1 and C2 can be measured respectively.

[0056] In the self-excited method test, because the CVT medium-voltage transformer is used as the test power supply, when measuring C1, the voltage on each component in the electromagnetic unit acts as an interference source. This interference affects the voltage amplitude and phase at the N-terminal through the distributed capacitance of the low-voltage end (N-terminal) of the voltage divider capacitor and its leads, thus affecting the measurement accuracy and causing the measured value to be larger than the actual value. When measuring C1, the potential at the N-terminal is 2kV to 3kV. There is a ground loss from the N-terminal (including the N-terminal terminal block) to C2. This loss causes the voltage phase at the N-terminal to lead the phase of the test power supply. (Standard capacitor C...) N The current will also shift forward, thus increasing the measured dielectric loss. If the insulation of the N-terminal terminal block is severely degraded and the loss increases, the test error will increase, potentially leading to misjudgment. When measuring C2, the low-voltage N-terminal of the capacitor divider is directly connected to the bridge, and the potential at the N-terminal is very low, resulting in a smaller measurement error.

[0057] In one embodiment, such as Figure 2 As shown, a method for correcting the dielectric loss measurement error of a capacitive voltage transformer is provided. This embodiment illustrates the application of this method to a device for correcting the dielectric loss measurement error of a capacitive voltage transformer, including the following steps:

[0058] Step 201: Construct an equivalent analysis circuit for dielectric loss measurement based on the equivalent circuit of dielectric loss, as the target circuit model;

[0059] The target circuit model can be used to quantitatively calculate the dielectric loss test data of the capacitive voltage transformer under the influence of interference branches.

[0060] In practical applications, based on the equivalent circuit of dielectric loss and the measurement principle of digital automatic dielectric loss meter, an equivalent analysis circuit for dielectric loss measurement can be constructed as the target circuit model.

[0061] In one example, an equivalent analysis circuit for dielectric loss measurement is constructed based on the measurement principle of a digital automatic dielectric loss meter, such as... Figure 3a As shown, its characteristic is that the voltage vectors across the test sample and the standard capacitor are equal to the power supply voltage vector. Therefore, this equivalent analysis circuit for dielectric loss measurement can reflect the equivalent circuit of dielectric loss, and the calculated data is consistent with the measurement data of the digital dielectric loss meter. The equivalent analysis circuit for dielectric loss measurement can serve as the basic circuit model for quantitatively calculating the dielectric loss test data of a capacitive voltage transformer under the influence of interference branches. Using this circuit, the test data of the digital dielectric loss meter can be calculated and analyzed.

[0062] Step 202: Obtain the target expression set corresponding to the target circuit model, and obtain the first dielectric loss value and the first capacitance parameter corresponding to the electromagnetic unit in the capacitive voltage transformer based on the target expression set.

[0063] As an example, the first dielectric loss value and the first capacitance parameter can be the dielectric loss value and capacitance parameter of the interference branch of the CVT electromagnetic unit.

[0064] In practical implementation, the dielectric loss test data under the influence of the interference branch can be calculated and derived using the equivalent analysis circuit of dielectric loss measurement, forming a set of calculation expressions (i.e., the set of target expressions). Then, based on this set of calculation expressions, the dielectric loss value and capacitance parameters of the interference branch of the CVT electromagnetic unit can be obtained by experimental methods, that is, the first dielectric loss value and the first capacitance parameter corresponding to the electromagnetic unit in the capacitive voltage transformer.

[0065] Step 203: Based on the test current parameter information, the first dielectric loss value, and the first capacitance parameter obtained from the preset test conditions, determine the dielectric loss measurement correction result, which is used as the corrected dielectric loss data corresponding to the capacitive voltage divider in the capacitive voltage transformer.

[0066] As an example, test current parameter information may include the total current amplitude and power angle parameters.

[0067] In practical applications, the full current amplitude and power angle parameters can be obtained based on the positive connection method test measurement. Then, the actual dielectric loss value of the CVT capacitor voltage divider can be calculated by combining the obtained dielectric loss value and capacitance parameters of the CVT electromagnetic unit interference branch. That is, the dielectric loss measurement correction result is determined as the corrected dielectric loss data corresponding to the capacitor voltage divider in the capacitor voltage transformer. Thus, the data error correction based on the positive connection method for measuring the dielectric loss of the CVT capacitor voltage divider is realized. For example, the inverse function function of MATLAB software can be used to calculate and solve it.

[0068] Compared to traditional methods, the technical solution in this embodiment corrects data errors by measuring the dielectric loss of the CVT capacitor voltage divider using the positive connection method. After correction calculation, the actual dielectric loss data of the CVT capacitor voltage transformer dielectric loss test can be obtained, thereby solving the problem of measurement errors in dielectric loss test data caused by the CVT's own structure.

[0069] In the aforementioned method for correcting the dielectric loss measurement error of a capacitive voltage transformer, an equivalent analysis circuit for dielectric loss measurement is constructed based on the equivalent circuit of dielectric loss as the target circuit model. Then, the set of target expressions corresponding to the target circuit model is obtained. Based on the set of target expressions, the first dielectric loss value and the first capacitance parameter corresponding to the electromagnetic unit in the capacitive voltage transformer are obtained. Then, based on the test current parameter information, the first dielectric loss value, and the first capacitance parameter obtained by measuring under preset test conditions, the dielectric loss measurement correction result is determined as the corrected dielectric loss data corresponding to the capacitive voltage divider in the capacitive voltage transformer. This method realizes the quantitative calculation of the dielectric loss measurement error of the capacitive voltage transformer, enables the correction of the dielectric loss measurement error of the capacitive voltage transformer, and improves the accuracy of the dielectric loss measurement of the capacitive voltage transformer.

[0070] In one embodiment, constructing an equivalent analysis circuit for dielectric loss measurement based on an equivalent circuit of dielectric loss as the target circuit model may include the following steps:

[0071] Based on the measurement mechanism of the digital automatic dielectric loss meter, an equivalent analysis circuit for dielectric loss measurement is constructed based on the dielectric loss equivalent circuit, which serves as the target circuit model.

[0072] Among them, the equivalent analysis circuit for dielectric loss measurement can be used as an equivalent circuit to characterize dielectric loss, and the dielectric loss data calculated based on the equivalent analysis circuit for dielectric loss measurement is consistent with the dielectric loss data measured by the digital automatic dielectric loss meter.

[0073] In one example, the measurement principle of a digital automatic dielectric loss analyzer can be represented as follows:

[0074] Based on the fundamental principle of dielectric loss, an alternating voltage is applied across the dielectric. At that time, there is an electric current. When a dielectric flows, it incurs active power losses (such as conductivity losses and polarization losses), which are called dielectric losses. The corresponding equivalent circuit and vector diagram for dielectric losses in parallel are shown below. Figure 3b As shown, the resistive current in the circuit... This refers to the active current and voltage generated by dielectric losses. and current The included angle between them is The power factor angle, The complementary angle δ is the dielectric loss angle.

[0075] tanδ is the dielectric loss factor, which can be expressed as a percentage, according to... Figure 3b It can be known that:

[0076]

[0077] The Schering bridge is a traditional instrument for measuring dielectric loss. It requires manual adjustment and has a relatively large measurement error. It has been largely replaced by more advanced digital automatic dielectric loss meters in the field.

[0078] The measurement principle of a digital automatic dielectric loss meter differs significantly from that of a traditional Schering bridge. It employs digital measurement circuitry to automatically measure dielectric loss, such as... Figure 3c As shown. In the measurement circuit, the current signal I to be measured... X I N Voltage signals are obtained after flowing through low-resistance sampling resistors R3 and R4, respectively. These signals are then converted into digital waveforms by a high-speed A / D converter and fed into the computer system. A Fourier transform is then used to obtain the current phasor. After phase shift compensation based on the voltage phase in the computer system, the sample Z... X Current phasor With standard capacitor C N Current vector The phase angle between them is the dielectric loss angle δ. The capacitance of the sample can be expressed by the capacitance current component I. C With standard capacitor current I N The ratio is calculated.

[0079] Traditional Schering bridges have two wiring methods: direct connection and reverse connection. Direct connection is suitable when the test object is not grounded, while reverse connection is used when one end of the test object is grounded.

[0080] Figure 3b This is a schematic diagram illustrating the principle of a digital automatic dielectric loss meter for measuring the dielectric loss of an ungrounded sample. For a sample grounded at one end, the digital automatic dielectric loss meter uses a high-voltage current sensor to detect the current. After obtaining the amplitude and phase parameters of the sample current, the data is transmitted to the computer system for measurement. Due to the use of high-speed, high-precision A / D and D / A converters, coupled with megabit-level digital transmission, the accuracy of the reverse connection reaches the level of the forward connection. For the digital automatic dielectric loss meter, the test wiring for measuring an ungrounded sample is still called the forward connection method, while the wiring for measuring a sample grounded at one end is called the reverse connection method.

[0081] In yet another example, for the equivalent analysis circuit of dielectric loss measurement, such as Figure 3c As shown, Figure 3d middle,

[0082] The sampling resistors R3 and R4 in digital automatic dielectric loss analyzers have resistance values ​​in the ohm range (e.g., in AI series dielectric loss analyzers, the sampling resistor R3 has a resistance value of 0.2-200Ω, and the resistance value of R4 is around 200Ω), while the impedance of the test sample and standard capacitor is generally in the megaohm range. X X N >>R3, R4, then U X with U,U N The deviation from U is only on the order of one ten-thousandth, thus, in engineering, the voltage values ​​across the test sample and standard capacitor can be considered equal to the power supply voltage. Furthermore, since the computer system of a digital automatic dielectric loss meter can perform phase shift compensation based on the voltage phase during dielectric loss measurement, an equivalent analysis circuit for dielectric loss measurement can be constructed (such as...). Figure 3a As shown in the figure, the dielectric loss data obtained by the theoretical calculation of this circuit model is consistent with the measurement data of the digital dielectric loss meter, and it is applicable to both the positive connection method and the reverse connection method of the digital dielectric loss meter.

[0083] exist Figure 3a In the case of the sample and the standard capacitor, the voltage vectors across both terminals are the source voltage vectors. Therefore:

[0084]

[0085] In this case, using complex numbers, the power supply voltage vector has an argument of 0, and the current vector... Argument The cotangent value is the dielectric loss value tanδ of the dielectric, that is:

[0086]

[0087] The equivalent analysis circuit model for dielectric loss measurement reflects the equivalent circuit diagram of dielectric loss, and the theoretical calculation data is consistent with the measurement data of the digital dielectric loss meter. Using the equivalent analysis circuit for dielectric loss measurement, the test data of the digital dielectric loss meter can be calculated and analyzed.

[0088] In this embodiment, based on the measurement mechanism of the digital automatic dielectric loss meter, an equivalent analysis circuit for dielectric loss measurement is constructed as the target circuit model, providing data support for subsequent error correction processing.

[0089] In one embodiment, obtaining the set of target expressions corresponding to the target circuit model may include the following steps:

[0090] The dielectric loss test data under the influence of interference branches is calculated based on the target circuit model, and the target expression set is formed based on the dielectric loss test data.

[0091] The target expression set can be used to characterize the relationship between the second dielectric loss value and the second capacitor parameter, the first dielectric loss value and the first capacitor parameter, and the dielectric loss measurement value corresponding to the capacitor voltage divider.

[0092] In practical applications, the theoretical calculation of CVT dielectric loss measurement data (positive polarity method) can be expressed as follows:

[0093] Figure 4a This is an equivalent analysis circuit diagram for measuring the dielectric loss and capacitance of a CVT capacitor divider using the direct connection method. The current vector... The cotangent value of the phase angle is the measured value of dielectric loss. From the dielectric loss and capacitance parameters of the capacitor divider C1 and C2, and the dielectric loss and capacitance parameters of the CVT electromagnetic unit to the CVT casing (ground), the measured value of dielectric loss can be calculated and derived. The calculation expression is as follows:

[0094]

[0095]

[0096]

[0097]

[0098]

[0099]

[0100]

[0101] In one example, for the error correction method of CVT dielectric loss measurement data (direct connection method measurement), the dielectric loss measurement value tan′δ and the test current vector can be derived by calculation based on the actual dielectric loss value and capacitance of capacitors C1 and C2, and the dielectric loss (tanδ3) and capacitance (C3) parameters of the CVT electromagnetic unit to the shell (ground) through the above equations (3)-(9). The value of tanδ3, C3, and the current vector are obtained. By using parameters such as C1 and C2 and solving equations, the actual dielectric loss values ​​of capacitors C1 and C2 can be calculated, thereby achieving error correction.

[0102] In this embodiment, dielectric loss test data under the influence of interference branches is calculated based on the target circuit model, and a set of target expressions is formed based on the dielectric loss test data, providing data support for subsequent error correction processing.

[0103] In one embodiment, obtaining the first dielectric loss value and the first capacitance parameter corresponding to the electromagnetic unit in the capacitive voltage transformer based on the target expression set may include the following steps:

[0104] Based on the target expression set, the first dielectric loss value and the first capacitance parameter corresponding to the electromagnetic unit are obtained according to the preset test wiring method.

[0105] In practical implementation, the dielectric loss and capacitance parameters of the CVT electromagnetic unit to the CVT casing (ground), namely the first dielectric loss value and the first capacitance parameter, can be obtained in the following way:

[0106] The dielectric loss and capacitance parameters of the CVT electromagnetic unit relative to the CVT casing (ground) can be obtained through on-site testing. For example, the test method is as follows: short-circuit the upper end of the capacitor divider to the N terminal, then connect it to the high-voltage core wire of the dielectric loss meter (using shielding as needed based on equipment conditions). Leave the end of the CVT primary winding (X terminal) unconnected, and short-circuit and ground the terminals of the secondary winding of the medium-voltage transformer. This test wiring measures the dielectric loss value of capacitors C1 and C2 connected in parallel and then in series with the electromagnetic unit. The equivalent circuit is shown below. Figure 4b As shown.

[0107] The total capacitance of capacitors C1 and C2 connected in parallel is C. P (C P =C1+C2), the total dielectric loss is tanδ P (tanδ P =(C1 tanδ1+C2tanδ2) / (C1+C2)), then:

[0108]

[0109]

[0110] Wherein, tanδ3 and C3 are the actual dielectric loss and capacitance of the CVT electromagnetic unit, respectively, and tanδ′3 and C′3 are the measured values ​​of dielectric loss and capacitance of the electromagnetic unit.

[0111] The capacitance and dielectric loss values ​​of capacitors C1 and C2 can be obtained by consulting historical test data of the equipment. The actual capacitance value of the CVT electromagnetic unit can be obtained from equation (10) above:

[0112]

[0113] The actual dielectric loss value of the electromagnetic unit can be obtained by solving the equation (11) using the solve command of MATLAB software.

[0114] In this embodiment, the first dielectric loss value and the first capacitance parameter corresponding to the electromagnetic unit are obtained according to the target expression set and the preset test wiring method, which provides data support for subsequent error correction processing.

[0115] In one embodiment, obtaining the first dielectric loss value and the first capacitance parameter corresponding to the electromagnetic unit according to a preset test wiring method may include the following steps:

[0116] The measured dielectric loss value and measured capacitance parameter of the electromagnetic unit are obtained according to the preset test wiring method; the measured capacitance parameter and the measured dielectric loss value are corrected to obtain the first dielectric loss value and the first capacitance parameter of the electromagnetic unit.

[0117] In practical applications, the total capacitance of capacitors C1 and C2 connected in parallel can reach tens to hundreds of nF, while the capacitance of the electromagnetic unit is generally 1 to 2 nF, i.e., C1 + C2 >> C3. Therefore, the test values ​​of dielectric loss and capacitance of the electromagnetic unit deviate little from the actual values, and data correction can be omitted, and the test data can be taken directly. Whether or not to perform electromagnetic unit test data correction can be determined based on the actual situation on site.

[0118] In this embodiment, the measured dielectric loss value and measured capacitance parameter corresponding to the electromagnetic unit are obtained by following a preset test wiring method. Then, the measured capacitance parameter and measured dielectric loss value are corrected to obtain the first dielectric loss value and first capacitance parameter corresponding to the electromagnetic unit. The data can be flexibly corrected according to the actual situation.

[0119] In one embodiment, determining the dielectric loss measurement correction result based on the test current parameter information obtained from preset test conditions, the first dielectric loss value, and the first capacitance parameter, as the corrected dielectric loss data corresponding to the capacitive voltage divider in the capacitive voltage transformer, may include the following steps:

[0120] According to the preset test conditions, the full current amplitude and power factor angle data are measured using the digital automatic dielectric loss meter and used as the test current parameter information; the current vector parameter is obtained based on the test current parameter information; and the dielectric loss measurement correction result is determined by combining the current vector parameter, the first dielectric loss value, and the first capacitance parameter, and used as the corrected dielectric loss data corresponding to the capacitive voltage divider in the capacitive voltage transformer.

[0121] In one example, the test current vector parameters (i.e., test current parameter information) measured using the positive polarity method can be obtained from a dielectric loss meter. For instance, the AI ​​series digital dielectric loss meter displays not only dielectric loss and capacitance values, but also the total current amplitude and power factor angle. The current vector (i.e., current vector parameters) can be obtained from the total current value I2 and the power factor angle ω2. Parameters:

[0122]

[0123] The capacitance values ​​of capacitors C1 and C2 can be obtained by measuring the capacitance values ​​of C1 and C2 using the self-excitation method or by directly consulting the historical test data or factory test data of the equipment.

[0124] In this embodiment, the full current amplitude and power factor angle data are measured using a digital automatic dielectric loss meter according to preset test conditions, and used as test current parameter information. Then, the current vector parameter is obtained based on the test current parameter information. Then, the dielectric loss measurement correction result is determined by combining the current vector parameter, the first dielectric loss value, and the first capacitance parameter. This result serves as the corrected dielectric loss data corresponding to the capacitor divider in the capacitor voltage transformer, which can realize the data error correction of the dielectric loss of the CVT capacitor divider based on the positive connection method.

[0125] In one embodiment, determining the corrected dielectric loss measurement result by combining the current vector parameter, the first dielectric loss value, and the first capacitance parameter, as the corrected dielectric loss data corresponding to the capacitive voltage divider in the capacitive voltage transformer, may include the following steps:

[0126] Based on the target expression set, the inverse function is calculated and solved according to the current vector parameters, the first dielectric loss value, and the first capacitance parameters to obtain the dielectric loss measurement correction result, which serves as the corrected dielectric loss data corresponding to the capacitive voltage divider in the capacitive voltage transformer.

[0127] In practical applications, the correction calculation method can be expressed as follows:

[0128] The positive connection method measures the combined dielectric loss tanδ0 of capacitors C1 and C2 connected in series.

[0129]

[0130] If tanδ1=tanδ2, then tanδ0=tanδ1=tanδ2. Therefore, we can assume that the dielectric loss values ​​of capacitors C1 and C2 are both tanδ0. Then, the above equations (3)-(4) can be transformed into:

[0131]

[0132]

[0133] In equations (14) and (15) and the above equations (5)-(8), tanδ0 is an unknown quantity, while the others are known quantities. The actual dielectric loss value tanδ0 can be obtained by solving the system of equations or by finding the inverse function. For example, the inverse function function of MATLAB software can be used to calculate and solve it, as follows:

[0134] Based on equations (14) and (15) and the above equations (5)-(8), equation (16) can be obtained through algebraic operations:

[0135]

[0136] Where tanδ0 is an unknown quantity, and the other parameters are known quantities. The value of tanδ0 can be obtained by using the inverse function finverse() in MATLAB software, which is used as the corrected actual dielectric loss value, that is, the corrected dielectric loss data corresponding to the capacitive voltage divider in the capacitive voltage transformer.

[0137] In one example, the relevant parameters and test data for a certain 500kV CVT can be represented in the following table:

[0138]

[0139] In yet another example, on-site testing can be conducted to verify this:

[0140] A CVT with leads at the first end (A′) of the intermediate transformer was selected for on-site testing and verification. This type of CVT can directly measure the dielectric loss and capacitance of capacitors C1 and C2, and the test data is relatively accurate. The test data of directly measuring the capacitance of C1 and C2 was used as the baseline data. The dielectric loss data measured by the positive connection method and corrected was compared with the baseline data: the measured value by the positive connection method was -0.218%, the corrected dielectric loss value was 0.0381%, and the baseline value was 0.0387%. The corrected dielectric loss value is basically consistent with the actual value, verifying that the dielectric loss data correction method in this embodiment is correct and effective.

[0141]

[0142] In this embodiment, by performing inverse function calculation based on the target expression set, current vector parameters, first dielectric loss value, and first capacitance parameters, the dielectric loss measurement correction result is obtained and used as the corrected dielectric loss data corresponding to the capacitor divider in the capacitor voltage transformer, thus realizing the data error correction of dielectric loss of the CVT capacitor divider.

[0143] In one embodiment, such as Figure 5 The diagram illustrates another method for correcting dielectric loss measurement errors in capacitive voltage transformers. In this embodiment, the method includes the following steps:

[0144] In step 501, based on the measurement mechanism of the digital automatic dielectric loss meter, an equivalent analysis circuit for dielectric loss measurement is constructed as the target circuit model, using the equivalent circuit of dielectric loss. In step 502, dielectric loss test data under the influence of interference branches is calculated based on the target circuit model, and a set of target expressions is formed based on the dielectric loss test data. This set of target expressions characterizes the relationship between the second dielectric loss value and the second capacitor parameter corresponding to the capacitor voltage divider, the first dielectric loss value and the first capacitor parameter, and the dielectric loss measurement value. In step 503, based on the set of target expressions, the first dielectric loss value and the first capacitor parameter corresponding to the electromagnetic unit are obtained according to the preset test wiring method. In step 504, according to the preset test conditions, the full current amplitude and power factor angle data are measured using the digital automatic dielectric loss meter, serving as the test current parameter information. In step 505, the current vector parameter is obtained based on the test current parameter information. In step 506, based on the target expression set, the inverse function or system of equations is calculated and solved according to the current vector parameters, the first dielectric loss value, and the first capacitance parameters to obtain the corrected dielectric loss measurement result, which serves as the corrected dielectric loss data corresponding to the capacitive voltage divider in the capacitive voltage transformer. It should be noted that the specific limitations of the above steps can be found in the above description of the specific limitations of a method for correcting dielectric loss measurement errors in a capacitive voltage transformer, and will not be repeated here.

[0145] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0146] Based on the same inventive concept, this application also provides a capacitor voltage transformer dielectric loss measurement error correction device for implementing the above-mentioned capacitor voltage transformer dielectric loss measurement error correction method. The solution provided by this device is similar to the solution described in the above method. Therefore, the specific limitations of one or more embodiments of the capacitor voltage transformer dielectric loss measurement error correction device provided below can be found in the limitations of the capacitor voltage transformer dielectric loss measurement error correction method described above, and will not be repeated here.

[0147] In one embodiment, such as Figure 6As shown, a device for correcting the dielectric loss measurement error of a capacitive voltage transformer is provided, comprising:

[0148] The equivalent analysis circuit construction module 601 is used to construct an equivalent analysis circuit for dielectric loss measurement based on the dielectric loss equivalent circuit, which serves as the target circuit model; the target circuit model is used to quantitatively calculate the dielectric loss test data of the capacitive voltage transformer under the influence of interference branches.

[0149] The dielectric loss data acquisition module 602 is used to acquire the target expression set corresponding to the target circuit model, and obtain the first dielectric loss value and the first capacitance parameter corresponding to the electromagnetic unit in the capacitive voltage transformer based on the target expression set.

[0150] The error correction module 603 is used to determine the dielectric loss measurement correction result based on the test current parameter information, the first dielectric loss value, and the first capacitance parameter obtained by measuring under preset test conditions, and use it as the corrected dielectric loss data corresponding to the capacitive voltage divider in the capacitive voltage transformer.

[0151] In one embodiment, the equivalent analysis circuit construction module 601 includes:

[0152] The target circuit model is used to obtain a sub-module, which is used to construct an equivalent analysis circuit for dielectric loss measurement based on the dielectric loss equivalent circuit according to the measurement mechanism of the digital automatic dielectric loss meter, and serves as the target circuit model;

[0153] The dielectric loss measurement equivalent analysis circuit is used as an equivalent circuit to characterize dielectric loss, and the dielectric loss data calculated based on the dielectric loss measurement equivalent analysis circuit is consistent with the dielectric loss data measured by the digital automatic dielectric loss meter.

[0154] In one embodiment, the dielectric loss data acquisition module 602 includes:

[0155] The target expression set is used to obtain a sub-module, which is used to calculate the dielectric loss test data under the influence of the interference branch according to the target circuit model, and to form the target expression set based on the dielectric loss test data;

[0156] The target expression set is used to characterize the relationship between the second dielectric loss value and the second capacitance parameter corresponding to the capacitive voltage divider, the first dielectric loss value and the first capacitance parameter, and the dielectric loss measurement value.

[0157] In one embodiment, the dielectric loss data acquisition module 602 includes:

[0158] The dielectric loss data acquisition submodule is used to acquire the first dielectric loss value and the first capacitance parameter corresponding to the electromagnetic unit according to the target expression set and a preset test wiring method.

[0159] In one embodiment, the dielectric loss data acquisition submodule includes:

[0160] The measurement data acquisition unit is used to acquire the measured dielectric loss value and measured capacitance parameter corresponding to the electromagnetic unit according to the preset test wiring method;

[0161] A data correction unit is used to correct the measured capacitance parameter and the measured dielectric loss value to obtain the first dielectric loss value and the first capacitance parameter corresponding to the electromagnetic unit.

[0162] In one embodiment, the error correction module 603 includes:

[0163] The current parameter information acquisition submodule is used to measure the full current amplitude and power factor angle data using the digital automatic dielectric loss meter according to the preset test conditions, and use them as the test current parameter information.

[0164] The current vector parameter acquisition submodule is used to obtain the current vector parameters based on the test current parameter information.

[0165] The corrected dielectric loss data acquisition submodule is used to combine the current vector parameters, the first dielectric loss value, and the first capacitance parameters to determine the corrected dielectric loss measurement result, which serves as the corrected dielectric loss data corresponding to the capacitive voltage divider in the capacitive voltage transformer.

[0166] In one embodiment, the submodule for obtaining the corrected dielectric loss data includes:

[0167] The inverse function solving unit is used to calculate and solve the inverse function or system of equations based on the target expression set, according to the current vector parameters, the first dielectric loss value, and the first capacitance parameters, to obtain the dielectric loss measurement correction result, which serves as the corrected dielectric loss data corresponding to the capacitive voltage divider in the capacitive voltage transformer.

[0168] Each module in the aforementioned capacitive voltage transformer dielectric loss measurement error correction device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in the processor of a computer device in hardware form or independent of it, or stored in the memory of a computer device in software form, so that the processor can call and execute the corresponding operations of each module.

[0169] In one embodiment, a computer device is provided, which may be a server, and its internal structure diagram may be as follows: Figure 7As shown, the computer device includes a processor, memory, and network interface connected via a system bus. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and a database. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage media. The database stores error correction data for capacitive voltage transformer dielectric loss measurement. The network interface communicates with external terminals via a network connection. When the computer program is executed by the processor, it implements a method for correcting errors in capacitive voltage transformer dielectric loss measurement.

[0170] Those skilled in the art will understand that Figure 7 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0171] In one embodiment, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to perform the following steps:

[0172] An equivalent analysis circuit for dielectric loss measurement is constructed based on the dielectric loss equivalent circuit, serving as the target circuit model; the target circuit model is used to quantitatively calculate the dielectric loss test data of the capacitive voltage transformer under the influence of interference branches;

[0173] Obtain the set of target expressions corresponding to the target circuit model, and based on the set of target expressions, obtain the first dielectric loss value and the first capacitance parameter corresponding to the electromagnetic unit in the capacitive voltage transformer;

[0174] Based on the test current parameter information, the first dielectric loss value, and the first capacitance parameter obtained from the preset test conditions, the dielectric loss measurement correction result is determined and used as the corrected dielectric loss data corresponding to the capacitive voltage divider in the capacitive voltage transformer.

[0175] In one embodiment, when the processor executes the computer program, it also implements the steps of the capacitive voltage transformer dielectric loss measurement error correction method in the other embodiments described above.

[0176] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, the computer program performing the following steps when executed by a processor:

[0177] An equivalent analysis circuit for dielectric loss measurement is constructed based on the dielectric loss equivalent circuit, serving as the target circuit model; the target circuit model is used to quantitatively calculate the dielectric loss test data of the capacitive voltage transformer under the influence of interference branches;

[0178] Obtain the set of target expressions corresponding to the target circuit model, and based on the set of target expressions, obtain the first dielectric loss value and the first capacitance parameter corresponding to the electromagnetic unit in the capacitive voltage transformer;

[0179] Based on the test current parameter information, the first dielectric loss value, and the first capacitance parameter obtained from the preset test conditions, the dielectric loss measurement correction result is determined and used as the corrected dielectric loss data corresponding to the capacitive voltage divider in the capacitive voltage transformer.

[0180] In one embodiment, when the computer program is executed by a processor, it also implements the steps of the capacitive voltage transformer dielectric loss measurement error correction method in the other embodiments described above.

[0181] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, performs the following steps:

[0182] An equivalent analysis circuit for dielectric loss measurement is constructed based on the dielectric loss equivalent circuit, serving as the target circuit model; the target circuit model is used to quantitatively calculate the dielectric loss test data of the capacitive voltage transformer under the influence of interference branches;

[0183] Obtain the set of target expressions corresponding to the target circuit model, and based on the set of target expressions, obtain the first dielectric loss value and the first capacitance parameter corresponding to the electromagnetic unit in the capacitive voltage transformer;

[0184] Based on the test current parameter information, the first dielectric loss value, and the first capacitance parameter obtained from the preset test conditions, the dielectric loss measurement correction result is determined and used as the corrected dielectric loss data corresponding to the capacitive voltage divider in the capacitive voltage transformer.

[0185] In one embodiment, when the computer program is executed by a processor, it also implements the steps of the capacitive voltage transformer dielectric loss measurement error correction method in the other embodiments described above.

[0186] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.

[0187] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0188] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A method for correcting error in dielectric loss measurement of a capacitive voltage transformer, characterized in that, The method comprises: According to the measurement mechanism of the digital automatic dielectric loss instrument, an equivalent analysis circuit for dielectric loss measurement is constructed based on the dielectric loss equivalent circuit, as a target circuit model; the target circuit model is used for quantitative calculation of the dielectric loss test data of the capacitive voltage transformer under the influence of the interference branch; the equivalent analysis circuit for dielectric loss measurement is used to characterize the equivalent circuit of dielectric loss, and the dielectric loss data calculated based on the equivalent analysis circuit for dielectric loss measurement is consistent with the dielectric loss data measured by the digital automatic dielectric loss instrument; A target expression set corresponding to the target circuit model is obtained, the target expression set being a set of calculation expressions associated with multiple parameters; the target expression set is used to represent the relationship between the second dielectric loss value and the second capacitance parameter of the capacitive voltage divider, the first dielectric loss value and the first capacitance parameter of the electromagnetic unit, and the test current vector of the capacitive voltage divider and the dielectric loss measurement value; Based on the target expression set, the first dielectric loss value and the first capacitance parameter of the electromagnetic unit in the capacitive voltage transformer are tested according to a preset test wiring mode; Based on the target expression set, the expression is obtained: wherein, to test the current vector, , is a second capacitance parameter, is a first capacitance parameter, is a first dielectric loss value, is a dielectric loss measurement correction result corresponding to the capacitance divider; According to the test current parameter information measured under the preset test condition, the first dielectric loss value, the first capacitance parameter, and the second capacitance parameter corresponding to the capacitive voltage divider, the expression is calculated and solved to determine the dielectric loss measurement correction result as the corrected dielectric loss data corresponding to the capacitive voltage divider in the capacitive voltage transformer; wherein the test current parameter information is measured by using the digital automatic dielectric loss instrument, and the test current parameter information is used to calculate the test current vector.

2. The method of claim 1, wherein, The target expression set corresponding to the target circuit model is obtained, including: According to the target circuit model, the dielectric loss test data under the influence of the interference branch is calculated, and the target expression set is formed based on the dielectric loss test data; The target expression set is used to represent the relationship between the second dielectric loss value and the second capacitance parameter of the capacitive voltage divider, the first dielectric loss value and the first capacitance parameter, and the test current vector and the dielectric loss measurement value.

3. The method of claim 1, wherein, The first dielectric loss value and the first capacitance parameter of the electromagnetic unit are obtained according to the preset test wiring mode, including: The measurement dielectric loss value and the measurement capacitance parameter of the electromagnetic unit are obtained according to the preset test wiring mode; The measurement capacitance parameter and the measurement dielectric loss value are corrected to obtain the first dielectric loss value and the first capacitance parameter of the electromagnetic unit.

4. The method according to any one of claims 1 to 3, characterized in that, According to the test current parameter information measured under the preset test condition, the first dielectric loss value, the first capacitance parameter, and the second capacitance parameter corresponding to the capacitive voltage divider, the expression is calculated and solved to determine the dielectric loss measurement correction result as the corrected dielectric loss data corresponding to the capacitive voltage divider in the capacitive voltage transformer, including: According to the preset test condition, the full current amplitude and power factor angle data are measured by using the digital automatic dielectric loss instrument as the test current parameter information, and the current vector parameter is obtained according to the test current parameter information; The expression is calculated and solved based on the current vector parameter, the first dielectric loss value, the first capacitance parameter, and the second capacitance parameter corresponding to the capacitance divider to determine a dielectric loss measurement correction result as corrected dielectric loss data corresponding to the capacitance divider in the capacitance voltage transformer.

5. The method of claim 4, wherein, The expression is calculated and solved based on the current vector parameter, the first dielectric loss value, the first capacitance parameter, and the second capacitance parameter corresponding to the capacitance divider to determine a dielectric loss measurement correction result as corrected dielectric loss data corresponding to the capacitance divider in the capacitance voltage transformer. The expression is calculated and solved based on the current vector parameter, the first dielectric loss value, the first capacitance parameter, and the second capacitance parameter corresponding to the capacitance divider to determine a dielectric loss measurement correction result as corrected dielectric loss data corresponding to the capacitance divider in the capacitance voltage transformer.

6. A device for correcting error in dielectric loss measurement of a capacitive voltage transformer, characterized by, The apparatus comprises: An equivalent analysis circuit construction module configured to construct a dielectric loss measurement equivalent analysis circuit based on a dielectric loss equivalent circuit according to a measurement mechanism of a digital automatic dielectric loss meter, as a target circuit model; the target circuit model is used to quantitatively calculate dielectric loss test data of the capacitance voltage transformer under the influence of the interference branch; the dielectric loss measurement equivalent analysis circuit is used to represent an equivalent circuit of dielectric loss, and the dielectric loss data calculated based on the dielectric loss measurement equivalent analysis circuit is consistent with the dielectric loss data measured by the digital automatic dielectric loss meter; A dielectric loss data acquisition module configured to acquire a target expression set corresponding to the target circuit model, and to test a first dielectric loss value and a first capacitance parameter corresponding to an electromagnetic unit of the capacitance voltage transformer according to a preset test wiring mode based on the target expression set; the target expression set is a set of multi-parameter associated calculation expressions; the target expression set is used to represent the relationship between a second dielectric loss value and a second capacitance parameter corresponding to a capacitance divider, the first dielectric loss value and the first capacitance parameter corresponding to the electromagnetic unit, and a test current vector and a dielectric loss measurement value; An error correction module configured to obtain an expression based on the target expression set: wherein, to test the current vector, , is a second capacitance parameter, is a first capacitance parameter, is a first dielectric loss value, is a dielectric loss measurement correction result corresponding to the capacitance divider; The error correction module is further configured to calculate and solve the expression based on test current parameter information measured under a preset test condition, the first dielectric loss value, the first capacitance parameter, and the second capacitance parameter corresponding to the capacitance divider to determine a dielectric loss measurement correction result as corrected dielectric loss data corresponding to the capacitance divider in the capacitance voltage transformer; wherein the test current parameter information is measured by using the digital automatic dielectric loss meter, and the test current parameter information is used to calculate the test current vector. 7.A computer device, comprising a memory and a processor, wherein the memory stores a computer program, and the computer device is configured to perform the method according to any one of claims 1-6 when the computer program is executed by the processor. The processor executes the computer program to implement the steps of the method of any one of claims 1 to 5.

8. A computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to implement the steps of the method of any one of claims 1 to 5.

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