A compensation method for a distributed overvoltage sensor and related systems and devices

Abstract

A compensation method of a distributed overvoltage sensor, comprising: obtaining an overvoltage measurement value through an overvoltage sensor installed below a power transmission line; and performing compensation calculation on the overvoltage measurement value to obtain an overvoltage correction value according to a pre-established compensation coefficient curve; the compensation coefficient curve is a simulation variable ratio and installation height function relationship calculated based on finite element simulation analysis of the overvoltage sensor, and is further corrected through actual measurement data of stray capacitance of the overvoltage sensor. The present application can effectively compensate the power frequency measurement result under the condition that the installation condition of the overvoltage sensor cannot guarantee stability, and the algorithm complexity is low, which provides feasibility for real-time compensation; the compensation steps include design variable ratio change curve calculation based on finite element analysis, compensation coefficient curve calculation, and compensation of actual measurement result. The present application has the advantages of high measurement accuracy, wide adaptability and small calculation amount.

Description

Technical Field

[0001] This invention belongs to the field of voltage measurement, specifically relating to a compensation method for a distributed overvoltage sensor and related systems and equipment. Background Technology

[0002] Overvoltage monitoring is crucial for insulation coordination and protection configuration of power equipment, and it forms the basis for post-fault diagnosis and accident handling. Compared to conventional voltage measurement, overvoltage monitoring needs to simultaneously meet the requirements for power frequency voltage and lightning overvoltage measurement. While physical resistor / resistor / capacitor voltage dividers are the most widely used voltage measurement devices in power systems, the transient performance of capacitive voltage dividers cannot meet the requirements for lightning measurement; and resistor and resistor-capacitor voltage dividers, containing resistive elements, are limited by heat dissipation and withstand voltage issues, and are only used in a few specific applications.

[0003] To address overvoltage measurement challenges in areas such as lightning monitoring and fault location, research institutions have proposed distributed voltage sensor designs, including overvoltage sensors based on stray capacitance suitable for line fault location and lightning strike location. These overvoltage sensors offer advantages in terms of measurement bandwidth, size, and cost; however, they struggle to completely shield against the influence of nearby conductors, resulting in limited measurement accuracy and interference resistance, and ultimately failing to meet the accuracy requirements for power frequency overvoltage measurement.

[0004] Therefore, distributed voltage sensors suffer from insufficient overvoltage measurement accuracy. Summary of the Invention

[0005] The purpose of this invention is to solve the problem of insufficient overvoltage measurement accuracy of distributed voltage sensors.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] A compensation method for a distributed overvoltage sensor includes: obtaining an overvoltage measurement value through the overvoltage sensor installed below the transmission line; calculating an overvoltage correction value by compensating the overvoltage measurement value according to a pre-established compensation coefficient curve; wherein the compensation coefficient curve is obtained by calculating the relationship function between the simulated turns ratio and the installation height based on the finite element simulation analysis of the overvoltage sensor, and then correcting it using the measured data of the stray capacitance of the overvoltage sensor.

[0008] Preferably, the process of establishing the pre-established compensation coefficient curve includes: obtaining the simulated transformer ratio of the sensor at each installation height through finite element model analysis and calculation of the overvoltage sensor, and then obtaining the relationship function between the simulated transformer ratio and the installation height; correcting the relationship function between the simulated transformer ratio and the installation height through the measured data of the stray capacitance of the overvoltage sensor to obtain the relationship function between the design transformer ratio and the height; and obtaining the compensation coefficient curve based on the ratio of the design transformer ratio under the stable operating condition of the overvoltage sensor and the relationship function between the design transformer ratio and the height.

[0009] Preferably, the step of obtaining the simulated turns ratio of the sensor at each installation height through finite element model analysis of the overvoltage sensor, and then obtaining the relationship function between the simulated turns ratio and the installation height, includes: Step A1, establishing an overvoltage sensor turns ratio formula and a finite element analysis model with the installation height as one of the parameters based on the actual physical structure of the overvoltage sensor; Step A2, calculating the Maxwell capacitance matrix of each electrode of the overvoltage sensor based on the finite element analysis model; Step A3, calculating the stray capacitance to ground of the measuring electrode and the shielding electrode based on the Maxwell capacitance matrix of each electrode; Step A4, gradually changing the installation height within a set range, and simultaneously repeating steps A2 and A3 to calculate the stray capacitance to ground of the measuring electrode and the shielding electrode corresponding to the gradually changing installation height, and then fitting a trend curve of stray capacitance changing with installation height; Step A5, importing the stray capacitance in the trend curve of stray capacitance changing with installation height into the voltage sensor turns ratio formula to obtain the relationship function between the simulated turns ratio and the installation height.

[0010] Preferably, the step of correcting the simulated transformer ratio and installation height relationship function using the stray capacitance measured data of the overvoltage sensor to obtain the design transformer ratio and height relationship function includes: determining the initial value of the least squares method using the simulated transformer ratio and installation height relationship function, and fitting and calculating the functional expression of the design transformer ratio changing with height using the stray capacitance measured data of the overvoltage sensor.

[0011] Preferably, obtaining the compensation coefficient curve based on the ratio of the design transformer ratio under stable operating conditions of the overvoltage sensor and the relationship function between the design transformer ratio and the height includes: Step B1, inputting the installation height into the relationship function between the sensor design transformer ratio and the installation height to calculate the design transformer ratio; Step B2, obtaining the compensation coefficient by the ratio of the design transformer ratio under stable operating conditions of the overvoltage sensor and the design transformer ratio calculated in Step B1; Step 3, gradually changing the installation height within a set range, simultaneously repeating Steps B1 and B2 to calculate the compensation coefficient corresponding to the gradually changing installation height, and fitting the compensation coefficient corresponding to the gradually changing installation height to obtain the compensation coefficient curve.

[0012] Preferably, the overvoltage sensor turns ratio formula is as follows:

[0013] K = U o / U i ≈C M1 / C s1 ≈C M2 / C s2 ;

[0014] Where K is the overvoltage sensor turns ratio; U o U is the voltage across the matching capacitor of the overvoltage sensor. i The voltage connected to the high-voltage terminal of the overvoltage sensor; C M1 C M2 For solid capacitors; C s1 C s2 This refers to stray capacitance to ground.

[0015] Preferably, the compensation coefficient is calculated using the following formula:

[0016]

[0017] In the formula, δ is the compensation coefficient; δ(h) is the variation function of the compensation coefficient with height; n0 is the design ratio of the overvoltage sensor under stable operating conditions; h is the installation height of the overvoltage sensor; n is the design ratio; and f(h) is the function of the design ratio with height.

[0018] Preferably, the design ratio as a function of height, f(h), is calculated using the following formula:

[0019] f(h) = a·h -b +N0;

[0020] Where h is the installation height of the overvoltage sensor; a and b are the regression coefficients determined by the nonlinear least squares method; and N0 is the regression constant determined by the nonlinear least squares method.

[0021] The present invention also provides an overvoltage measurement system, comprising: an overvoltage sensor installed below a transmission line for measuring overvoltage, an overvoltage measurement module connected to the overvoltage sensor, and an overvoltage compensation module connected to the overvoltage measurement module; the overvoltage compensation module includes a computational unit for implementing the compensation method of the distributed overvoltage sensor.

[0022] The present invention also provides a distributed overvoltage measurement experimental device, comprising: a distributed overvoltage sensor having a measuring electrode and a shielding electrode and being insulated and suspended; a signal conditioning circuit connected to the measuring electrode and the shielding electrode respectively and having a grounding terminal; a power frequency voltage source or surge generator connected in series between the grounding terminal and ground; a primary side-recording device connected in parallel across the power frequency voltage source or surge generator; and a secondary side-recording device having one end connected to the grounding terminal and the other end connected to the measuring electrode.

[0023] The present invention also provides a computer device comprising: one or more processors; said processors being configured to store one or more programs; and when said one or more programs are executed by said one or more processors, implementing the compensation method for a distributed overvoltage sensor.

[0024] The present invention also provides a computer-readable storage device, characterized in that it stores a computer program thereon, which, when executed, implements the compensation method for a distributed overvoltage sensor.

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0026] 1. A compensation method for a distributed overvoltage sensor, comprising: obtaining an overvoltage measurement value through the overvoltage sensor; calculating an overvoltage correction value by compensating the overvoltage measurement value according to a pre-established compensation coefficient curve and the actual installation height of the overvoltage sensor; wherein the compensation coefficient curve is obtained by correcting the simulated transformer ratio and installation height relationship function based on finite element simulation analysis of the overvoltage sensor and then using the measured data of the overvoltage sensor. This invention reduces errors by compensating for overvoltage measurements using a pre-established compensation curve, thus possessing the advantages of high measurement accuracy, wide applicability, and low computational complexity. Attached Figure Description

[0027] Figure 1 This is a flowchart of a compensation method for a distributed overvoltage sensor according to the present invention;

[0028] Figure 2 This is the schematic diagram of the distributed overvoltage sensor of the present invention;

[0029] Figure 3 This is the prototype structure and equivalent circuit diagram of the distributed overvoltage sensor of the present invention;

[0030] Figure 4 This is a schematic diagram of a distributed overvoltage measurement experimental device according to the present invention;

[0031] Figure 5 This is a comparison diagram of the measurement signal and the correction signal of this invention;

[0032] Among them: 1-insulating components, 2-signal conditioning circuit, 3-power frequency voltage source or surge generator, 4-primary side recording equipment, 5-secondary side recording equipment, 6-distributed overvoltage sensor, S1-shielding electrode, S2-measuring electrode. Detailed Implementation

[0033] To address the issues of insufficient measurement accuracy and anti-interference capability in distributed overvoltage sensors due to the lack of external shielding, Academician Zheng Jianchao proposed a design scheme for distributed overvoltage sensors utilizing the principle of equipotential shielding. The circuit diagram is as follows: Figure 2 As shown, this distributed overvoltage sensor is structurally an inverted capacitive voltage divider. Based on the isolated conductor effect, it utilizes the stable stray capacitance between the measuring electrode and the ground to construct a stable high-voltage capacitor; the shielded electrode significantly reduces conducted interference from surrounding conductors to the measuring electrode. However, this distributed overvoltage sensor requires the measuring electrode to maintain a certain distance from the ground and adjacent conductors to ensure relatively stable stray capacitance to ground. In practical engineering, however, the following two problems exist:

[0034] (1) When the distance to the ground does not meet the isolated conductor effect requirement (the height above the ground or the minimum distance to the adjacent conductor is greater than 10 times the measuring electrode), it will cause the measurement ratio to deviate from the design value, introducing a non-negligible measurement error, making it difficult to achieve the 3% requirement for power frequency overvoltage measurement accuracy.

[0035] (2) The stray capacitance of the measuring electrode / shielding electrode to ground changes non-proportionally with varying height, which disrupts the balance condition of the two arms of the bridge measurement circuit. The power frequency measurement error is not stable. At 20 times the height of the measuring electrode conductor, the measurement error is close to 1%, but at lower heights, the measurement error increases significantly.

[0036] Example 1

[0037] like Figure 1 As shown, this invention discloses a compensation method for a distributed overvoltage sensor, which includes: obtaining an overvoltage measurement value through an overvoltage sensor installed below a transmission line; calculating an overvoltage correction value by compensating the overvoltage measurement value according to a pre-established compensation coefficient curve; the compensation coefficient curve is obtained by calculating the relationship function between the simulated turns ratio and the installation height based on the finite element simulation analysis of the overvoltage sensor, and then correcting it using the measured data of the stray capacitance of the overvoltage sensor.

[0038] When a distributed overvoltage sensor measures power frequency voltage, the measurement accuracy is affected by the installation conditions. If the height does not meet the requirements, stray capacitance to ground of the overvoltage sensor will occur, which will cause the double arms of the bridge measurement circuit to not meet the balance condition, and ultimately cause the voltage division ratio of the measurement branch to deviate from the design value.

[0039] In principle, by analyzing and calculating the finite element model of the sensor, the design transformation ratio of the sensor at various installation heights can be obtained. If the finite element simulation analysis results are used as the compensation basis for the power frequency measurement results of the overvoltage sensor, real-time compensation of the measurement data can be performed under conditions where the installation height differs from the design value. Step 1: Theoretical transformation ratio calculation of the overvoltage sensor

[0040] Figure 2 The diagram shows a typical overvoltage sensor measurement circuit. Figure 3 The diagram shows the prototype structure and equivalent circuit of a distributed overvoltage sensor; where: C M1 To measure the electrode matching capacitance, C M2 C is a matching capacitor for the shielding electrode. s1 C s2 These represent the stray capacitances to ground of the measuring electrode and the shielding electrode, respectively; Cp represents the stray capacitance between the measuring electrode and the shielding electrode; and HV represents the high-voltage terminal. Wherein, C... M1 C M2 For a solid capacitor, C s1 C s2 For stray capacitance to ground, "C" M1 +C s1 "and "C M2 +C s2 "Construct two balancing bridge arms, due to C" s2 Shielding, C s1 It is largely unaffected by adjacent conductors.

[0041] Under ideal operating conditions, for power frequency measurements, the voltage U is taken from the high-voltage terminal HV of the sensor. i As input, the matching capacitance C is measured. M1 Voltage U across the terminals o (s) is the output, and the sensor variation is shown in the following formula:

[0042] K = U o / U i ≈C M1 / C s1 ≈C M2 / C s2 (1)

[0043] But C s1 C s2 Size is related to altitude above ground. Due to the different dimensions of the shielding electrode and the measuring electrode, Cs1 C s2 Instead of changing proportionally with height, in this case, "C" M1 +C s1 "and "C M2 +C s2 "The balance of the bridge arm was thus disrupted."

[0044] A finite element analysis model was established based on the actual physical structure of the overvoltage sensor. The installation height was controlled to vary within a certain range near the design value. The Maxwell capacitance matrix of each electrode of the overvoltage sensor was calculated, and the stray capacitance to ground of the measuring electrode and the shielding electrode was derived from this. The stray capacitance to ground of the two electrodes (C) was obtained. s1 C s2 The trend of change with installation height.

[0045] According to stray capacitance (C) s1 C s2 Substituting the trend curve of the change with installation height into Formula 1, we can obtain the trend curve of the design ratio changing with installation height.

[0046] Step 2: Obtain and calculate the compensation coefficient curve based on the measured data.

[0047] Step 1 provides the theoretical transformation ratio of the overvoltage sensor at different installation heights. However, as mentioned earlier, C... s1 C s2 The change is not proportional to the height, which introduces additional measurement errors. Under these conditions, it is necessary to design a compensation algorithm to correct the measurement results using both measured and simulation data, minimizing the difference between the theoretical and actual change ratios.

[0048] Since the signal to be compensated is a power frequency signal, the compensation algorithm only addresses the amplitude error introduced during the measurement process. The compensation process involves solving for an amplification factor to minimize the error between the compensated signal and the actual measured signal. In step 1, the process curve of the simulated transformer ratio changing with the installation height at different heights is obtained, and the compensation can be performed using the simulated transformer ratio at the actual installation height. In practical use, considering that there is no abrupt change in the stray capacitance to ground and the change process is relatively smooth, the function expression of the transformer ratio changing with height, n = f(h), is calculated using the least squares method. The compensation factor δ can be calculated by the ratio of the design transformer ratio n0 to n = f(h) under stable operating conditions.

[0049] During the measurement process, the actual installation height of the equipment is first obtained, and the compensation coefficient is calculated according to the expression. Multiplying the compensation coefficient by the measurement result yields the corrected measurement result. The calculation process of the compensation coefficient can be given by equation (1) according to the above process:

[0050]

[0051] In the above formula: f(h)=a·h -b +N0

[0052] In the formula, δ(h) is the variation function of the compensation coefficient related to height; n0 is the design ratio of the equipment under stable operating conditions; h is the installation height; n is the simulation ratio at that installation height in the simulation ratio curve; a and b are the regression coefficients of the simulation ratio curve determined by the nonlinear least squares method; N0 is the regression constant of the simulation ratio curve determined by the nonlinear least squares method; the expression for the installation height h-simulation ratio compensation coefficient δ that satisfies the exponential function regression relationship is determined by a, b, and N0.

[0053] Step 3: Measurement result correction and compensation

[0054] Based on the recorded actual installation height, the power frequency measurement compensation coefficient δ at the actual installation height of the equipment is calculated using equation (2). The actual measurement result is then multiplied by the amplification factor δ, which is equivalent to amplifying the secondary measurement output signal by δ times, thus obtaining the compensated power frequency measurement waveform. For example... Figure 5 As shown, the compensated result remains within a small error range compared to the measurement result at the designed installation height.

[0055] Power frequency measurements using distributed overvoltage sensors rely on relatively stable installation conditions. When these conditions are difficult to stabilize, compensation is needed to reduce measurement errors. The overvoltage sensor compensation method proposed in this invention can effectively compensate for power frequency measurements even under unstable installation conditions, while maintaining low algorithm complexity, thus providing feasibility for real-time compensation. The compensation steps include calculating the design transformer ratio curve based on finite element analysis, calculating the compensation coefficient curve, and compensating for the actual measurement results.

[0056] This method has the following advantages:

[0057] (1) High measurement accuracy: Compared with the measurement results of the uncalibrated overvoltage sensor, this compensation method can make the measurement results closer to the actual overvoltage, effectively reducing the power frequency measurement error caused by the installation height of the overvoltage sensor not reaching the design value in the power frequency measurement.

[0058] (2) Wide range of applications: The sensor model used for calibration is built based on finite element analysis environments such as ANSYS or COMSOL. The model can be modified and calculated within a relatively flexible range. It can quickly simulate overvoltage sensors of different sizes. Under the condition that the physical size, material and other model parameters are accurate, the simulation calculation results can better match the actual capacitance size, and have good reusability and flexibility.

[0059] (3) Low computational load: After the overvoltage sensor parameters are fixed, the compensation coefficient δ can be obtained by on-site calculation or querying a predefined table. The algorithm complexity is low, and the correction can be completed on low-power computing devices.

[0060] Example 2

[0061] Based on the same inventive concept, the present invention also provides an overvoltage measurement system, comprising: an overvoltage sensor installed below a transmission line for measuring overvoltage, an overvoltage measurement module connected to the overvoltage sensor, and an overvoltage compensation module connected to the overvoltage measurement module; the overvoltage compensation module includes a computational unit for implementing a compensation method for a distributed overvoltage sensor as described in Embodiment 1, thereby compensating and correcting the overvoltage measurement value of the overvoltage measurement module.

[0062] Example 3

[0063] like Figure 4 As shown, based on the same inventive concept, the present invention also provides a distributed overvoltage measurement experimental device, which includes: a distributed overvoltage sensor 6 having a measuring electrode S1 and a shielding electrode S2 and being insulated and suspended; a signal conditioning circuit 2 connected to the measuring electrode S2 and the shielding electrode S1 respectively and having a grounding terminal; a power frequency voltage source or surge generator 3 connected in series between the grounding terminal and ground; a primary side recording device 4 connected in parallel across the power frequency voltage source or surge generator 3; and a secondary side recording device 5 having one end connected to the grounding terminal and the other end connected to the measuring electrode S2.

[0064] Building such Figure 4 The measurement experimental platform shown was used to measure a 5kV power frequency high voltage signal under unbalanced conditions. At an installation height of 2.08m, the measurement results showed that the actual transformation ratio of the sensor was n = 9307.8, which deviated from the design transformation ratio n0 = 10000 under stable conditions by approximately 6.85%. Without compensation, the measurement results would contain significant errors.

[0065] Following step 1 of Example 1, finite element analysis was used to calculate the design ratio of the sensor at various installation heights, and the functional relationship between the sensor design ratio and installation height was obtained. The calculated functional relationship between the design ratio n and installation height h of this sensor model satisfies equation (3), and the correlation coefficient R... 2 =0.9996.

[0066]

[0067] Following step 2 of Example 1, the installation height h = 2.08m of the sensor to be calibrated under unbalanced conditions is substituted into equation (3) to calculate the compensation coefficient δ = 1.0434. Following step 3, the original signal is amplified by a factor of δ to complete the calibration. The calibrated signal is compared with the high-voltage measurement signal as follows: Figure 4 As shown, the error between the actual transformer ratio and the design transformer ratio under steady-state conditions decreased from 6.85% to 2.88%.

[0068] Example 4

[0069] Based on the same inventive concept, this invention also provides a computer device, which includes a processor and a memory. The memory stores a computer program, which includes program instructions. The processor executes the program instructions stored in the computer storage medium. The processor may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing and control core of the terminal, suitable for implementing one or more instructions, specifically suitable for loading and executing one or more instructions in the computer storage medium to implement corresponding method flows or corresponding functions, thereby implementing the steps of a distributed overvoltage sensor compensation method in the above embodiments.

[0070] Example 5

[0071] Based on the same inventive concept, this invention also provides a storage device, specifically a computer-readable storage medium (Memory). The computer-readable storage medium is a memory device within a computer device used to store programs and data. It is understood that the computer-readable storage medium here can include both the built-in storage medium within the computer device and extended storage media supported by the computer device. The computer-readable storage medium provides storage space containing the terminal's operating system. Furthermore, this storage space also contains one or more instructions suitable for loading and execution by a processor. These instructions can be one or more computer programs (including program code). It should be noted that the computer-readable storage medium here can be high-speed RAM or non-volatile memory, such as at least one disk storage device. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the steps of the compensation method for a distributed overvoltage sensor in the above embodiments.

[0072] The above are merely embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of the claims of the present invention pending approval.

Claims

1. A compensation method for a distributed overvoltage sensor, characterized in that, The method includes: obtaining overvoltage measurement values ​​through an overvoltage sensor installed below the transmission line; calculating the overvoltage correction value by compensating the overvoltage measurement value according to a pre-established compensation coefficient curve; the compensation coefficient curve is obtained by calculating the relationship function between the simulated turns ratio and the installation height based on the finite element simulation analysis of the overvoltage sensor, and then correcting it with the measured data of the stray capacitance of the overvoltage sensor. The process of establishing the pre-established compensation coefficient curve includes: obtaining the simulated transformer ratio of the sensor at each installation height through finite element model analysis and calculation of the overvoltage sensor, and then obtaining the relationship function between the simulated transformer ratio and the installation height; correcting the relationship function between the simulated transformer ratio and the installation height through the measured data of the stray capacitance of the overvoltage sensor to obtain the relationship function between the design transformer ratio and the height; and obtaining the compensation coefficient curve based on the ratio of the design transformer ratio under the stable operating condition of the overvoltage sensor and the relationship function between the design transformer ratio and the height.

2. The compensation method for a distributed overvoltage sensor as described in claim 1, characterized in that, The process of obtaining the simulated turns ratio of the overvoltage sensor at various installation heights through finite element model analysis and calculation, and then obtaining the relationship function between the simulated turns ratio and the installation height, includes the following steps: Step A1, establishing an overvoltage sensor turns ratio formula and a finite element analysis model with the installation height as one of the parameters based on the actual physical structure of the overvoltage sensor; Step A2, calculating the Maxwell capacitance matrix of each electrode of the overvoltage sensor based on the finite element analysis model; Step A3, calculating the stray capacitance to ground of the measuring electrode and the shielding electrode based on the Maxwell capacitance matrix of each electrode; Step A4, gradually changing the installation height within a set range, and simultaneously repeating steps A2 and A3 to calculate the stray capacitance to ground of the measuring electrode and the shielding electrode corresponding to the gradually changing installation height, and then fitting a trend curve of stray capacitance changing with installation height; Step A5, importing the stray capacitance from the trend curve of stray capacitance changing with installation height into the voltage sensor turns ratio formula to obtain the relationship function between the simulated turns ratio and the installation height.

3. The compensation method for a distributed overvoltage sensor as described in claim 1, characterized in that, The process of obtaining the design ratio-height relationship function by correcting the simulated ratio-installation height relationship function using stray capacitance measured data from the overvoltage sensor includes: determining the initial value using the least squares method based on the simulated ratio-installation height relationship function, and fitting and calculating the functional expression of the design ratio changing with height using stray capacitance measured data from the overvoltage sensor.

4. The compensation method for a distributed overvoltage sensor as described in claim 1, characterized in that, The step of obtaining the compensation coefficient curve based on the ratio of the design transformer ratio under stable operating conditions of the overvoltage sensor and the relationship function between the design transformer ratio and the height includes: Step B1, inputting the installation height into the relationship function between the sensor design transformer ratio and the installation height to calculate the design transformer ratio; Step B2, obtaining the compensation coefficient by the ratio of the design transformer ratio under stable operating conditions of the overvoltage sensor and the design transformer ratio calculated in Step B1; Step 3, gradually changing the installation height within a set range, simultaneously repeating Steps B1 and B2 to calculate the compensation coefficient corresponding to the gradually changing installation height, and fitting the compensation coefficient corresponding to the gradually changing installation height to obtain the compensation coefficient curve.

5. The compensation method for a distributed overvoltage sensor as described in claim 2, characterized in that, The overvoltage sensor turns ratio formula is as follows: K = U o / U i ≈ C M1 / C s1 ≈ C M2 / C s2 ; Where K is the overvoltage sensor turns ratio; U o This is the voltage across the matching capacitor of the overvoltage sensor; U i The voltage connected to the high-voltage terminal of the overvoltage sensor; C M1 , C M2 It is a physical capacitor; C s1 , C s2 This refers to stray capacitance to ground.

6. The compensation method for a distributed overvoltage sensor as described in claim 4, characterized in that, The compensation coefficient is calculated using the following formula: ； In the formula, δ is the compensation coefficient; δ(h) is the variation function of the compensation coefficient with height. η is the design transformer ratio under stable operating conditions for the overvoltage sensor; h is the installation height of the overvoltage sensor; n is the design transformer ratio. To design a function that varies the ratio with height.

7. The compensation method for a distributed overvoltage sensor as described in claim 6, characterized in that, The function of the design ratio as a function of height Calculate using the following formula: ； Where h is the installation height of the overvoltage sensor; a and b are the regression coefficients determined by the nonlinear least squares method; The regression constant is determined by the nonlinear least squares method.

8. An overvoltage measurement system, characterized in that, The system includes: an overvoltage sensor installed below the transmission line for measuring overvoltage, an overvoltage measurement module connected to the overvoltage sensor, and an overvoltage compensation module connected to the overvoltage measurement module; the overvoltage compensation module includes a computing unit for implementing a compensation method for a distributed overvoltage sensor as described in any one of claims 1-7.

9. A computer device, characterized in that, include: One or more processors; The processor is used to store one or more programs; When the one or more programs are executed by the one or more processors, a compensation method for a distributed overvoltage sensor as described in any one of claims 1 to 7 is implemented.

10. A computer-readable storage device, characterized in that, It contains a computer program, which, when executed, implements a compensation method for a distributed overvoltage sensor as described in any one of claims 1 to 7.

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