Voltage measuring device and method considering participation of water drops in surface flashover

Abstract

The invention relates to a voltage measuring device and method considering participation of water drops in surface flashover, the device comprises a high-voltage power supply (1), a simulation device (2) and an oscilloscope (3), one end of the oscilloscope (3) is connected with the high-voltage power supply (1) through a high-voltage probe (4), the other end of the oscilloscope (3) is connected with a current coil (6), and the high-voltage power supply (1) comprises a signal generator and a power amplifier. The simulation device (2) comprises a first finger-shaped electrode (21), a second finger-shaped electrode (22) and an insulation experiment platform (25), the insulation experiment platform (25) comprises a transparent top plate (251) with a nut hole, a transparent bottom plate (252) with scale marks and a stand column (253), compared with the prior art, the device is used for carrying out a measurement experiment, the surface flashover voltage when water drops participate in surface flashover can be effectively measured, and the measurement accuracy is improved. And the degree of influence on the surface flashover voltage of the insulating material when the water drops participate in the surface flashover at different frequencies is evaluated through the degree of participation.

Description

Technical Field

[0001] The invention relates to an electrical insulation testing device, in particular to a device and method for measuring the surface flashover voltage of an insulating material taking into account the influence of water drops under simulated natural environment conditions. Background Art

[0002] Traditional surface flashover voltage measurements of insulating materials are usually carried out in a dry state, ignoring the actual working conditions of insulating materials in a humid environment. This method cannot accurately simulate the flashover characteristics of insulating materials in a humid environment, resulting in differences between the test results and actual application conditions. In a humid environment, water droplets often exist on the surface of insulating materials. The presence of water droplets will change the conductivity of the surface of the insulating material, thereby affecting the flashover characteristics. The dynamic behavior of water droplets has an important influence on the flashover voltage, which is often ignored by traditional measurement methods. In real applications, insulating materials are often exposed to humid environments, such as outdoor power equipment, aerospace devices, etc. Therefore, accurately simulating and measuring the flashover characteristics of insulating materials in a humid environment is of great significance for design, testing and quality control. The traditional surface flashover voltage measurement method of insulating materials cannot take into account the influence of the dynamic behavior of water droplets, resulting in differences between the test results and actual application conditions. Therefore, a new measurement device and method are needed to more accurately simulate and measure the flashover characteristics of insulating materials in a humid environment.

[0003] Chinese patent application CN115078929A discloses a device and method for measuring the surface flashover voltage of polymer materials under different media, which is used to measure the surface flashover voltage values ​​of polymer materials under different media, and provides experimental support for the demonstration of voltage-resistant materials of power equipment. However, this device can and can only be used to measure the surface flashover voltage values ​​of polymer materials under different media, and cannot be used to measure the surface flashover voltage values ​​of insulating materials in a humid environment. Summary of the invention

[0004] The purpose of the present invention is to provide a voltage measurement device and method that takes into account the participation of water droplets in surface flashover, so as to more accurately simulate and measure the flashover characteristics of insulating materials in a humid environment and measure the influence of the distribution of water droplets on the flashover voltage.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] A voltage measurement device considering water droplets participating in surface flashover includes a high-voltage power supply and an oscilloscope, one end of the oscilloscope is connected to the high-voltage power supply through a high-voltage probe, and the other end is connected to a current coil, the high-voltage power supply includes a signal generator and a power amplifier, and a simulation device is connected to the high-voltage power supply and the oscilloscope, wherein the simulation device includes:

[0007] A first finger-shaped electrode, a second finger-shaped electrode and an insulating experimental platform, wherein the insulating experimental platform includes a transparent top plate with a nut hole, a transparent bottom plate with scale lines and a column, the first finger-shaped electrode is connected to a high-voltage power supply through a wire, the second finger-shaped electrode is connected to the ground via a protective resistor and a current coil in sequence, the first finger-shaped electrode and the second finger-shaped electrode are fixed through the nut hole of the transparent top plate, and the fixed spacing is controlled by the scale lines on the transparent bottom plate.

[0008] Furthermore, the signal generator can generate electrical signals of different frequencies and amplitudes, including direct current, alternating current and pulses, and the power amplifier amplifies the electrical signals and outputs high-voltage power.

[0009] Furthermore, the transparent top plate has no less than 6 nut holes, which are evenly arranged perpendicular to the central axis of the transparent top plate.

[0010] Furthermore, the scale lines on the transparent bottom plate are located on one side or both sides of the insulating experimental platform, and are used to control the fixed positions of the first finger-shaped electrode and the second finger-shaped electrode and the titration position of the water droplets.

[0011] Furthermore, the first finger-shaped electrode includes a connecting screw and a high-voltage electrode, one end of the connecting screw is connected to the high-voltage power supply through a wire, and the other end passes through a nut hole of the transparent top plate to fix the high-voltage electrode.

[0012] Furthermore, the second finger-shaped electrode includes a connecting screw and a grounding electrode, one end of the connecting screw is connected to the ground via a protective resistor and a current coil in sequence, and the other end passes through a nut hole of the transparent top plate to fix the grounding electrode.

[0013] Furthermore, the chamfers of the high voltage electrode and the grounding electrode are less than 5 mm, the width is at least 2 mm greater than the outer diameter of the connecting screw, and the length is not greater than the length of the transparent bottom plate.

[0014] According to the above-mentioned voltage measurement device considering the participation of water droplets in surface flashover, a voltage measurement method considering the participation of water droplets in surface flashover is designed, comprising the following steps:

[0015] Step S1, building an insulating experimental platform, and using the scale lines on the transparent bottom plate to determine the positions of the first finger-shaped electrode, the second finger-shaped electrode and the water droplet titration;

[0016] Step S2, placing a flat plate sample with a clean surface on a transparent bottom plate, and fixing the first finger-shaped electrode and the second finger-shaped electrode on the flat plate sample according to the determined positions through the nut holes of the transparent top plate;

[0017] Step S3, titrating the uniformly dyed deionized water according to the determined position and recording the starting position and starting length of the water drop;

[0018] Step S4, connecting a high voltage power supply, a simulation device and an oscilloscope;

[0019] Step S5, starting the high voltage power supply, monitoring and adjusting the waveform and amplitude of the signal through an oscilloscope, and recording the flashover voltage at which the water droplets break down, as well as the final position and final length of the water droplets;

[0020] Step S6, turning off the high voltage power supply, calculating the participation of water droplets in the surface flashover and the displacement factor of water droplets according to the recorded data, and analyzing the influence of water droplets on the surface flashover.

[0021] Furthermore, the voltage measurement method considering the participation of water droplets in surface flashover is characterized in that the calculation formula for the participation of water droplets in surface flashover is:

[0022]

[0023] Among them, Y is the participation, U w is the flashover voltage with water droplets, U n It is the flashover voltage without water droplets;

[0024] The calculation formula of the displacement factor of the water drop is:

[0025]

[0026] Among them, ΔX is the water drop displacement factor, L1 is the initial length of the water drop, and X is the distance after the water drop displacement flashes.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] 1. The present invention provides a voltage measurement device that takes into account the participation of water droplets in surface flashover, which effectively simulates the influence of water droplets on the surface flashover voltage of insulating materials under natural environmental conditions, and improves the accuracy and reliability of the flashover characteristic test of insulating materials in a humid environment;

[0029] 2. The present invention provides a voltage measurement method that takes into account the participation of water droplets in surface flashover. By testing the flashover voltage of insulating materials in a humid environment and calculating the degree of participation, the influence of water droplets in the surface flashover of insulating materials can be effectively evaluated, which provides a scientific basis for understanding the role of water droplets in electrical insulation systems. It has important practical application value for the design and testing of outdoor power equipment and aerospace devices in humid environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is an overall schematic diagram of the measuring device of the present invention;

[0031] Figure 2 This is a schematic diagram of the insulation experimental platform of the present invention;

[0032] Figure 3 A front view of the distribution of nut holes on a transparent top plate in one embodiment of the present invention;

[0033] Figure 4 A top view of the distribution of nut holes on a transparent top plate in one embodiment of the present invention;

[0034] Figure 5 This is a line diagram showing the effect of water droplets on flashover voltage in one embodiment of the present invention;

[0035] Figure 6 This is an example of a broken line diagram of the relationship between the water drop displacement factor and the flashover voltage in one embodiment of the present invention. DETAILED DESCRIPTION

[0036] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0037] Example 1

[0038] This embodiment discloses a voltage measurement device that takes into account the participation of water droplets in surface flashover, such as Figure 1 As shown, the experimental device of this embodiment includes a high voltage power supply 1, a simulation device 2 and an oscilloscope 3.

[0039] The high-voltage power supply 1 includes a signal generator and a power amplifier. One end of the oscilloscope 3 is connected to the high-voltage power supply 1 through a high-voltage probe 4, and the other end is connected to the current coil 6. The simulation device 2 includes:

[0040] The first finger-shaped electrode 21, the second finger-shaped electrode 22 and the insulating experimental platform 25, wherein the insulating experimental platform 25 is as follows Figure 2 As shown, it includes a transparent top plate 251 with nut holes, a transparent bottom plate 252 with scale lines and four or more columns 253. The first finger-shaped electrode 21 is connected to the high-voltage power supply through a wire, and the second finger-shaped electrode 22 is connected to the ground through a protective resistor 5 and a current coil 6 in sequence. The first finger-shaped electrode 21 and the second finger-shaped electrode 22 are fixed through the nut holes of the transparent top plate 251, and the fixed spacing is controlled by the scale lines on the transparent bottom plate 252.

[0041] In this embodiment, the high-voltage power supply 1 is a variable-frequency high-voltage power supply, which includes a signal generator and a TREK high-voltage power amplifier. By adjusting the output signal of the signal generator, the frequency of the input voltage can be changed, and then amplified by the TREK high-voltage power amplifier to achieve the required high-voltage output.

[0042] The insulation test platform 25 is recommended to use transparent materials such as plastic and plexiglass, which is conducive to observing the position and distribution of water droplets. The upper and lower plates are rectangular or square plate structures of a certain thickness. The optimal thickness is 10-50mm. The material has good transparency at this thickness. The length and width are determined by the electrode size and the size of the sample being tested.

[0043] In order to facilitate the application of high voltage and the installation and fixation of graphite electrodes, six M8 nut holes are designed on the transparent top plate 251 of the insulating experimental platform 25. These nut holes provide fixing points for installing and fixing the finger electrodes. The number and position of the nut holes are designed to ensure the stability and balance of the finger electrodes. In this embodiment, the distribution of the nut holes is as follows: Figure 3 , 4 As shown, there are a total of 6 M8 nut holes, three nut holes on the left and right of the center axis of the upper plate, and the center distance between each nut hole is 24mm.

[0044] The transparent bottom plate 252 of the insulating experimental platform 25 is equipped with scale lines, which are usually set along one or both sides of the transparent bottom plate 252. It consists of a series of scale lines, which are usually marked in millimeters or other suitable units. In this embodiment, the length of the scale lines set according to the transparent bottom plate 252 is 20 cm, and the minimum spacing is 1 mm, which can ensure the accuracy and reliability of distance measurement.

[0045] Before the experiment, researchers need to select the appropriate scale line as a reference according to the experimental requirements and design parameters. Then, according to the experimental design, place the finger electrodes next to the scale lines and use the nut holes to fix the position of the electrodes. By carefully aligning the finger electrodes with the specific scale lines, it can be ensured that the position and distance of the finger electrodes are consistent with the experimental requirements.

[0046] In this embodiment, the first finger-shaped electrode 21 includes a connecting screw 211 and a high-voltage electrode 212 . One end of the connecting screw 211 is connected to the high-voltage power supply 1 through a wire, and the other end passes through a nut hole of the transparent top plate 251 to fix the high-voltage electrode 212 .

[0047] The second finger-shaped electrode 22 includes a connecting screw 221 and a grounding electrode 222. One end of the connecting screw 221 is connected to the ground via the protection resistor 5 and the current coil 6 in sequence, and the other end passes through the nut hole of the transparent top plate to fix the grounding electrode 222.

[0048] The high voltage electrode 212 and the ground electrode 222 are recommended to be made of graphite or aluminum. The screw can be of M6, M8 or other sizes. The electrode width is required to be at least 2 mm larger than the outer diameter of the screw and must be larger than the distance between the two nut holes to stabilize the electrode. The electrode length cannot exceed the length of the transparent bottom plate 252. The electrode chamfer must be less than 5 mm to ensure that the electric field at the bottom of the electrode will not be distorted and will not form a slightly uneven electric field. In this embodiment, graphite electrodes are selected as the high voltage electrode 212 and the ground electrode 222, with a chamfer radius of 2 mm.

[0049] Example 2

[0050] This embodiment is based on a voltage measurement device that takes into account the participation of water droplets in surface flashover in Embodiment 1, and discloses a voltage measurement method that takes into account the participation of water droplets in surface flashover. The specific steps are as follows.

[0051] Step 1, build an insulation experimental platform 25, prepare a transparent top plate 251 with nut holes made of organic glass insulation, a transparent bottom plate 252 with scale lines, and more than four pillars 253, and ensure that the surface is clean and flat;

[0052] Assemble the components and use the scale lines on the transparent bottom plate 252 to determine the positions of the first finger-shaped electrode 21, the second finger-shaped electrode 22 and the water droplet.

[0053] Step 2, placing a 0.5 mm SiR sheet with a clean and dust-free surface on the transparent bottom plate 252;

[0054] The positions of the first finger-shaped electrode 21 and the second finger-shaped electrode 22 are determined by using the scale lines, and the first finger-shaped electrode 21 and the second finger-shaped electrode 22 are fixed on the 0.5 mm SiR sheet according to the determined positions through the nut holes of the transparent top plate 251 .

[0055] Step 3, pre-staining treatment, prepare deionized water and add an appropriate amount of commonly used chemical staining agent (such as methylene blue);

[0056] Stir the mixture to dissolve the stain and ensure that the stain has fully penetrated and formed a noticeable blue color.

[0057] Step 4, put the evenly dyed deionized water into the micro-injector, and titrate it on the SiR slice according to the determined position, control the position and amount of titration to ensure the accuracy of the experiment, and record the starting position and starting length of the water drop after titration.

[0058] Step 5, connect the high-voltage power supply 1 and the oscilloscope 3 to the insulation experiment platform 2, ensure that the connection is firm, and check whether the signal transmission is normal. According to the experimental requirements, select multiple frequencies (such as 10Hz, 20Hz, 30Hz, 40Hz, 50Hz, etc.), and gradually adjust the output frequency of the high-voltage power supply to control the electrical signal during the experiment.

[0059] Step 6, start the high-voltage power supply 1, and monitor and adjust the waveform and amplitude of the signal through the oscilloscope 3 to ensure that the electrical signal during the experiment meets expectations, and record the flashover voltage at which the water droplet breaks down, as well as the final position and final length of the water droplet;

[0060] Through experiments, we can obtain data such as the flashover voltage at which the water droplets break down, as well as the final position and final length of the water droplets.

[0061] The data shown in Table 1 are the flashover voltage values ​​of water droplets at different frequencies.

[0062] Table 1 Flashover voltage data

[0063]

[0064] According to the experimental data, the participation index and the displacement factor of the water droplets can be calculated, and a line diagram showing the influence of the water droplets on the flashover voltage and a line diagram showing the relationship between the water droplet displacement factor and the flashover voltage can be drawn, as shown in Figure 2. Figure 5 and Figure 6 shown.

[0065] The participation index is a parameter that measures the effect of the distribution of water droplets (distance from the electrode position) on the flashover voltage. The formula is as follows:

[0066]

[0067] Among them, Y is the participation, U w is the flashover voltage with water droplets, U n It is the flashover voltage without water droplets.

[0068] Under the influence of the electric field force, the water droplets will first experience deformation, and then may be displaced. This displacement is particularly significant when the water droplets are not located in the center of the electrode. When the water droplets are affected by the electric field force, their shape will change due to the action of the electric field, forming a flatter or elongated shape. At this time, the contact area and electric field distribution of the water droplets will change, thus affecting their conductivity.

[0069] When a water droplet is displaced, its relative position between the electrodes also changes, and this displacement has a non-negligible effect on the flashover voltage. Specifically, the displacement of a water droplet may cause a local change in the electric field strength, which in turn affects the critical value of the flashover voltage. In some cases, the displacement of a water droplet may bring it closer to the electrode, thereby reducing the flashover voltage, while in other cases, the distance of the water droplet may cause the flashover voltage to increase.

[0070] Therefore, an in-depth analysis of the displacement factor of water droplets and their influence on the flashover voltage is crucial to understanding the electrical performance of insulating materials in a humid environment. The displacement factor formula of water droplets is as follows:

[0071]

[0072] Among them, ΔX is the water drop displacement factor, L1 is the initial length of the water drop, and X is the distance after the water drop displacement flashes.

[0073] The obtained displacement factor data are shown in Table 2 below.

[0074] Table 2 Displacement factor data

[0075]

[0076] Through detailed analysis of the experimental data, we can draw the following conclusions:

[0077] The presence of water droplets significantly reduces the surface flashover voltage, and its effect varies with the location of the water droplets and the frequency of the applied voltage.

[0078] Close to the positive electrode: Under high frequency conditions, the electric field changes quickly, and the polarization response of water molecules cannot keep up with the speed of the electric field change, resulting in a decrease in the participation of water droplets near the positive electrode. This may be because under high frequency conditions, the electric field changes quickly, while the polarization response of water droplets is relatively slow and cannot effectively follow the electric field changes, resulting in a decrease in the flashover voltage.

[0079] Electrode middle position: The participation of water droplets increases with the increase of frequency, which may be because the polarization and discharge process of water droplets in the middle position in the electric field is more complicated. At higher frequencies, the electric field changes faster, which may enhance the ion migration and polarization process inside the water droplets, thereby increasing their contribution to the flashover voltage.

[0080] Under the action of AC electric field, the polarization of water as a medium is a dynamic process. As the frequency increases, the polarization response speed of water molecules cannot keep up with the speed of electric field change, resulting in a decrease in effective polarization. Therefore, as the frequency increases, the impedance of the medium to the electric field decreases, and the electric field strength required to achieve the flashover condition increases. Therefore, the flashover voltage of the water droplet in the middle position increases with the increase of frequency.

[0081] Water droplets near the positive electrode will show a lower flashover voltage under high-frequency conditions. This may be because the high-frequency electric field accelerates the release and ionization process of electrons near the positive electrode, so that sufficient electric field strength can be achieved at a lower voltage to induce electrical breakdown.

[0082] from Figure 6 It can be seen that with the increase of frequency, the displacement factors near the positive electrode and between the electrodes show an upward trend. This shows that the high-frequency electric field has a significant effect on the deformation and displacement of water droplets, especially near the positive electrode, where the displacement factor of water droplets changes more significantly.

[0083] The displacement factor near the positive electrode is significantly higher than that in the middle of the electrode, indicating that when the water droplets are close to the electrode, their displacement and deformation have a greater impact on the flashover voltage. This may be because the water droplets close to the electrode are subjected to a higher electric field strength, resulting in stronger deformation and displacement.

[0084] As the voltage frequency increases, the high-frequency electric field makes the displacement and deformation of the water droplets more significant, which in turn affects the critical value of the flashover voltage. The different positions of the water droplets on the electrodes will significantly affect their displacement and participation, especially in the area close to the electrode, where the behavior of the water droplets has a more obvious impact on the flashover voltage.

[0085] The measurement system and participation calculation method provided by the present invention can effectively evaluate the influence of water droplets on the surface flashover of insulating materials, which is of great significance for improving the accuracy and reliability of flashover characteristic testing of insulating materials in a humid environment.

[0086] These findings not only provide a scientific basis for understanding the role of water droplets in electrical insulation systems, but also have important practical application value for the design and testing of outdoor power equipment and aerospace components in humid environments.

[0087] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A voltage measurement device taking into account the participation of water droplets in surface flashover, comprising a high-voltage power supply (1) and an oscilloscope (3), wherein one end of the oscilloscope (3) is connected to the high-voltage power supply (1) through a high-voltage probe (4), and the other end is connected to a current coil (6), characterized in that: The high-voltage power supply (1) includes a signal generator and a power amplifier. The simulation device (2) is connected to the high-voltage power supply (1) and the oscilloscope (3). The simulation device (2) includes: A first finger-shaped electrode (21), a second finger-shaped electrode (22) and an insulating experimental platform (25), wherein the insulating experimental platform (25) comprises a transparent top plate (251) with a nut hole, a transparent bottom plate (252) with scale lines and a column (253); the first finger-shaped electrode (21) is connected to a high-voltage power supply via a wire; the second finger-shaped electrode (22) is connected to the ground via a protective resistor (5) and a current coil (6) in sequence; the first finger-shaped electrode (21) and the second finger-shaped electrode (22) are fixed via the nut hole of the transparent top plate (251), and the fixed spacing is controlled by the scale lines on the transparent bottom plate (252).

2. A voltage measurement device considering water droplets participating in surface flashover according to claim 1, characterized in that: The signal generator can generate electrical signals of different frequencies and amplitudes, including direct current, alternating current and pulses. The power amplifier amplifies the electrical signals and outputs high-voltage power.

3. A voltage measurement device considering water droplets participating in surface flashover according to claim 1, characterized in that: The transparent top plate (251) has no less than 6 nut holes which are evenly arranged perpendicular to the central axis of the transparent top plate (251).

4. A voltage measurement device considering water droplets participating in surface flashover according to claim 1, characterized in that: The scale lines on the transparent bottom plate (252) are located on one side or both sides of the insulating experimental platform (25) and are used to control the fixed positions of the first finger-shaped electrode (21) and the second finger-shaped electrode (22) and the titration position of the water droplets.

5. A voltage measurement device taking into account the participation of water droplets in surface flashover according to claim 1, characterized in that: The first finger-shaped electrode (21) comprises a connecting screw (211) and a high-voltage electrode (212); one end of the connecting screw (211) is connected to the high-voltage power supply (1) via a wire, and the other end passes through a nut hole of the transparent top plate (251) to fix the high-voltage electrode (212).

6. A voltage measurement device considering water droplets participating in surface flashover according to claim 1, characterized in that: The second finger-shaped electrode (22) comprises a connecting screw (221) and a grounding electrode (222); one end of the connecting screw (221) is connected to the ground via a protective resistor (5) and a current coil (6) in sequence, and the other end passes through a nut hole of a transparent top plate (251) to fix the grounding electrode (222).

7. A voltage measurement device taking into account the participation of water droplets in surface flashover according to claim 5 or 6, characterized in that: The chamfers of the high voltage electrode (212) and the grounding electrode (222) are less than 5 mm, the width is at least 2 mm greater than the outer diameter of the connecting screw (221), and the length is no greater than the length of the transparent bottom plate (252).

8. A voltage measurement method taking into account the participation of water droplets in surface flashover using the voltage measurement device according to any one of claims 1 to 7, characterized in that: The method comprises the following steps: Step S1, constructing an insulating experimental platform (25), and using the scale lines on the transparent bottom plate (252) to determine the positions of the first finger-shaped electrode (21), the second finger-shaped electrode (22) and the water droplet for titration; Step S2, placing a flat plate sample with a clean surface on the transparent bottom plate (252), and fixing the first finger-shaped electrode (21) and the second finger-shaped electrode (22) on the flat plate sample according to the determined positions through the nut holes of the transparent top plate (251); Step S3, titrating the uniformly dyed deionized water according to the determined position and recording the starting position and starting length of the water drop; Step S4, connecting the high voltage power supply (1), the simulation device (2) and the oscilloscope (3); Step S5, starting the high voltage power supply (1), monitoring and adjusting the waveform and amplitude of the signal through the oscilloscope (3), and recording the flashover voltage at which the water droplet breaks down, as well as the final position and final length of the water droplet; Step S6, turning off the high voltage power supply (1), calculating the participation of water droplets in the occurrence of surface flashover and the displacement factor of water droplets based on the recorded data, and analyzing the influence of water droplets on surface flashover.

9. A voltage measurement method considering water droplets participating in surface flashover according to claim 8, characterized in that: The flat plate pattern is a thin sheet made of insulating material, which is used to simulate the working condition of the insulating material in a wet environment.

10. A voltage measurement method considering water droplets participating in surface flashover according to claim 8, characterized in that: The calculation formula for the participation of the water droplets in the surface flashover is: Among them, Y is the participation, U w is the flashover voltage with water droplets, U n It is the flashover voltage without water droplets; The calculation formula of the displacement factor of the water drop is: Among them, ΔX is the water drop displacement factor, L1 is the starting length of the water drop, and X is the distance after the water drop displacement flashes.

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