A method for testing a sample of an insulator for a surface flashover

Abstract

This invention discloses a method for conducting a surface flashover test on insulator test pieces. The test pieces include control test pieces and experimental test pieces, which have identical structures. There are two or more experimental test pieces. The specific steps of the experimental method are as follows: Step a: Immerse each experimental test piece in its respective chemical cleaning agent, with the immersion time gradually increasing for each test piece; Step b: Prepare artificial dirt and apply it to the test pieces. After coating, the salt density and ash density of each test piece are equal; Step c: Use a testing device to obtain and record the flashover voltage and leakage current of each test piece when flashover occurs. Compared with existing technologies, the surface flashover test method for insulator test pieces provided by this invention simplifies operation and provides higher experimental accuracy.

Description

Technical Field

[0001] This invention relates to the field of insulator testing technology, and in particular to a method for conducting a surface flashover test on an insulator test piece. Background Technology

[0002] Silicone rubber insulators possess excellent properties such as low surface energy, high mechanical strength, and strong resistance to flashover. With the rapid development of my country's power industry, composite silicone rubber insulators have been more widely used. Data shows that the number of composite insulators operating at voltage levels of 66kV and above in my country's power grid exceeds 10 million, playing a crucial role in the normal operation of electrical equipment such as substations and converter stations. Although composite silicone rubber insulators have stronger resistance to flashover compared to other insulators, dirt can still accumulate on their surface under electrostatic forces. This leads to widespread flashover accidents alongside the widespread use of composite silicone rubber insulators. These flashover accidents have a large impact area, long duration, and cause significant economic losses, posing a great safety threat to the operation of the power system. Therefore, finding a safe and efficient cleaning method for silicone rubber insulators is urgently needed.

[0003] Cleaning with chemical cleaning agents has advantages such as high resistivity, small water volume, and relatively ideal cleaning effect, and is widely regarded by researchers at home and abroad as a suitable cleaning method. However, silicone rubber materials will exhibit varying degrees of swelling when immersed in small-molecule chemical cleaning agents with different formulations. After being immersed in chemical cleaning agents, the insulators in the swollen state will change in both physical and electrical properties.

[0004] Existing techniques for conducting flashover tests on insulator materials under swelling conditions are rather cumbersome. Summary of the Invention

[0005] In order to overcome the shortcomings of the cumbersome experimental methods in the prior art, this invention proposes a simple method for testing the flashover along the surface of insulator test pieces.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A method for conducting a surface flashover test on an insulator test piece, comprising a control test piece and experimental test pieces, the test pieces having identical structures, and two or more experimental test pieces. The specific steps of the test method are as follows:

[0008] Step a: Immerse the test pieces in their respective chemical cleaning agents, with the immersion time gradually increasing for each test piece; Step b: Prepare artificial dirt and apply it to the test pieces. After application, the salt density and ash density of each test piece should be equal.

[0009] Step c: Use the testing device to obtain and record the flashover voltage of each test piece and the leakage current when the test piece flashes over.

[0010] Furthermore, the chemical cleaning agent is placed inside the container, and the oxygen inside the container is purged before proceeding to step a.

[0011] Furthermore, the testing device includes a power supply, a voltage regulating module, a support plate, electrodes, a voltage measurement module, and a current measurement module. The voltage regulating module is connected to the power supply, the support plate is used to support the test piece, the electrodes are connected to the voltage regulating module, the voltage measurement module is connected to the electrodes, and the current measurement module is connected to the electrodes.

[0012] Further, step c specifically includes:

[0013] Step d: Place the test piece on the support plate, connect the electrodes to both ends of the test piece and apply a test voltage to the test piece. Then, increase the test voltage uniformly through the voltage adjustment module until the test piece flashes over. Obtain and record the voltage value of the test voltage when the test piece flashes over through the voltage measurement module. Obtain and record the peak value and image of the leakage current during the flashover process of the test piece through the current measurement module.

[0014] Step e: Repeat step d four times;

[0015] Step f: Calculate the arithmetic mean of the test voltage values ​​measured in step d five times when the test piece flashes over, i.e., the flashover voltage; Step g: Calculate the flashover voltage of all test pieces, the peak value of the leakage current when the test piece flashes over, and the image based on steps d to f.

[0016] Furthermore, the electrode includes a first electrode and a second electrode, and the voltage regulating module includes a positive terminal and a negative terminal. The first electrode is connected to the positive terminal, and the second electrode is connected to the negative terminal. A loop is formed between the first electrode, the second electrode, and the voltage regulating module. The loop is equipped with a protective resistor and a voltage divider module. One end of the voltage divider module is connected to the first electrode, and the other end of the voltage divider module is grounded. The voltage measurement module is connected to the first electrode, and the current measurement module is connected to the second electrode.

[0017] Further, in step b, the test piece is coated using a window pane device. The window pane device includes two parallel first adjusting rods and two parallel second adjusting rods. A rectangular window is formed between the first adjusting rods and the second adjusting rods. The first adjusting rods are provided with a first adjusting groove, and the second adjusting rods are provided with a second adjusting groove. The first adjusting rods and the second adjusting rods are fixedly connected together by a first connecting member, which passes through the first adjusting groove and the second adjusting groove.

[0018] When applying stain to the test piece, first adjust the size of the window of the window pane device according to the area to be stained. Then, fix the first adjusting rod and the second adjusting groove together through the first connector. Place the test piece under the window pane device and use a dropper to drip artificial dirt onto the test piece through the window.

[0019] Furthermore, the electrode is U-shaped and includes two extensions and a bent portion located between the extensions. During step d, the window pane device is placed on the support plate. The end of the extension away from the bent portion is fixedly connected to the first adjustment groove through the second connector. The electrode is arranged between the second adjustment rods, and the second adjustment rods abut against the electrode. The bent portion abuts against the test piece.

[0020] Furthermore, the container includes a receiving part, a first connecting pipe, and a second connecting pipe. Both the first and second connecting pipes are connected to the receiving part. The first connecting pipe is provided with a valve, and the second connecting pipe is provided with a sealing element. The sealing element includes an insert, which is at least partially disposed within the second connecting pipe. A first sealing ring is provided between the insert and the second connecting pipe. The insert has an annular protrusion, and a second sealing ring is provided between the annular protrusion and the second connecting pipe. The insert has a rotating groove, which includes a first end and a second end. The first end is connected to the receiving part, and the second end is connected to the atmosphere. The inner diameter of the rotating groove gradually increases from the first end to the second end. The sealing element also includes a rotating body, which is at least partially rotatably connected within the rotating groove. A third sealing ring is provided between the rotating body and the rotating groove. A winding wheel is rotatably connected within the insert. A wire groove is provided on the side of the insert near the receiving part. A pull wire is connected to the winding wheel and passes through the wire groove. A transmission assembly is provided between the winding wheel and the rotating body.

[0021] Furthermore, the rotating body includes a first rotating part and a second rotating part, both of which are disposed within a rotating groove. The first rotating part is disposed on the side of the second rotating part near the receiving part. The first rotating part and the rotating groove are adapted to each other. A transmission rod is fixedly connected to the side of the first rotating part near the second rotating part. The second rotating part is provided with a transmission groove. The transmission rod passes through the transmission groove and is rotatably connected to the transmission groove. A fourth sealing ring is provided between the transmission rod and the transmission groove. A fifth sealing ring is provided between the second rotating part and the rotating groove. A pressing block is provided at the end of the transmission rod away from the first rotating part. The pressing block abuts against the side of the second rotating part away from the first rotating part.

[0022] Furthermore, the transmission assembly includes a driven bevel gear fixedly connected to the winding wheel and a drive bevel gear fixedly connected to the first rotating part, wherein the driven bevel gear and the drive bevel gear mesh.

[0023] Compared with existing technologies, the insulator test piece surface flashover test method provided by the present invention can simplify the operation and achieve higher experimental accuracy. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of an experimental specimen, representing an embodiment of this application, positioned above a chemical cleaning agent.

[0025] Figure 2 This is a cross-sectional view of the seal according to an embodiment of this application.

[0026] Figure 3 This is a schematic diagram of an experimental specimen being immersed in a chemical cleaning agent, as shown in an embodiment of this application.

[0027] Figure 4 This is a schematic diagram of a window pane device according to an embodiment of this application.

[0028] Figure 5 This is a schematic diagram of the window pane device according to an embodiment of this application after electrodes have been installed.

[0029] Figure 6 This is a schematic diagram of a test piece placed into a testing device according to an embodiment of this application. Detailed Implementation

[0030] The technical solution of the present invention will be further described in detail below through embodiments and in conjunction with the accompanying drawings.

[0031] See Figures 1 to 6 A method for conducting a surface flashover test on an insulator test piece is disclosed. The test piece 11 includes a control test piece and an experimental test piece, and the test pieces 11 have the same structure. Specifically, the test pieces 11 are identical in material and dimensions. The material of the test pieces 11 is the same as that used in insulators in practice, such as silicone rubber. There are two or more experimental test pieces. In this embodiment, four experimental test pieces and one control test piece are used. The test pieces 11 must be clean. Specifically, the test pieces 11 need to be wiped with anhydrous ethanol and dried before performing the following steps.

[0032] The specific steps of the experimental method are as follows:

[0033] Step a: Immerse the experimental specimens in their respective chemical cleaning agents, with the immersion time gradually increasing for each specimen. Immersion time refers to the duration from the moment the specimen is immersed in the chemical cleaning agent until it is removed. The immersion times vary for each specimen. In this embodiment, the immersion time for each specimen is less than or equal to 200 minutes, and the immersion times are evenly distributed. Specifically, the immersion times for each specimen are 50 minutes, 100 minutes, 150 minutes, and 200 minutes. Through the above steps, four experimental specimens with different degrees of swelling are obtained.

[0034] As one implementation method, the chemical cleaning agent is placed in container 12. Before step a, the oxygen in container 12 is purged to reduce the effect of oxygen on the swelling of the experimental sample. Specifically, a vacuum pump can be used to evacuate the air in container 12 to purge the oxygen; alternatively, an inert gas can be introduced into container 12 to purge the oxygen. In this embodiment, during step a, the experimental sample is placed in container 12 without immersing it in the chemical cleaning agent. Then, the air in container 12 is evacuated using a vacuum pump, and the experimental sample is then immersed in the chemical cleaning agent. After a preset immersion time, the experimental sample is removed from container 12 and allowed to dry.

[0035] Step b: Prepare artificial dirt and apply it to test pieces 11. After application, the salt density and ash density of each test piece 11 should be equal. The artificial dirt includes soluble salts and insoluble dirt.

[0036] The process of preparing the artificial contaminant is as follows: First, the mass of soluble salt in test piece 11 is obtained by multiplying the area of ​​the contamination on test piece 11 by the required salt density. Second, the mass of insoluble contaminant in test piece 11 is obtained by multiplying the area of ​​the contamination on test piece 11 by the required ash density. Third, the mass of soluble salt to be prepared is obtained by multiplying the first mass by a magnification factor, and fourth, the mass of insoluble contaminant to be prepared is obtained by multiplying the second mass by the magnification factor. The magnification factor is between 50 and 100. In this embodiment, the magnification factor is 100. The third mass of soluble salt and the fourth mass of insoluble contaminant are weighed using a weighing device. The soluble salt consists of sodium chloride and calcium sulfate. The mass ratio of sodium chloride to calcium sulfate in the soluble salt is 0.25. Kaolin or diatomaceous earth can be used as the insoluble contaminant.

[0037] The weighed soluble salts and insoluble contaminants are placed in a measuring cup, and an appropriate amount of water is added. After stirring evenly, a suspension is formed. The resulting suspension is then divided into equal portions corresponding to the magnification factor. In this embodiment, the suspension is divided into 100 equal portions.

[0038] In step b, when coating the test piece 11, five portions of the suspension are taken and dripped onto five test pieces 11 sequentially using a dropper. Then, they are air-dried and sealed for storage. These steps ensure good uniformity of the artificial contamination on the test piece 11.

[0039] To better control the coating area when coating the test piece 11, a window pane device 13 is used. The window pane device 13 includes two parallel first adjusting rods 131 and two parallel second adjusting rods 132, forming a rectangular window between them. The first adjusting rods 131 have a first adjusting groove 1311, and the second adjusting rods 132 have a second adjusting groove 1321. The orientation of the first adjusting groove 1311 and the second adjusting groove 1321 is perpendicular. The first adjusting rods 131 and 132 are fixedly connected together by a first connecting member 133, which passes through the first adjusting groove 1311 and the second adjusting groove 1321. In this embodiment, the first connecting member 133 is a bolt. When the bolt passes through the first adjustment groove 1311 and the second adjustment groove 1321, and the size of the window needs to be adjusted, the first adjustment rod 131 and the second adjustment rod 132 slide relative to each other, the first connector 133 slides relative to the first adjustment groove 1311, and the first connector 133 slides relative to the second adjustment groove 1321. Then the first connector 133 is tightened, and the first adjustment rod 131 and the second adjustment rod 132 are fixedly connected together through the first connector 133.

[0040] When applying stain to the test piece 11, first adjust the size of the window of the window pane device 13 according to the area to be stained. Then, fix the first adjusting rod 131 and the second adjusting groove 1321 together through the first connector 133. Place the test piece 11 under the window pane device 13 and use a dropper to drip artificial dirt onto the test piece 11 through the window.

[0041] Step c: Use the test device 14 to obtain and record the flashover voltage of each test piece 11 and the leakage current when the test piece 11 flashes over.

[0042] The testing device 14 includes a power supply 141, a voltage regulating module 142, a support plate 143, an electrode 144, a voltage measurement module 145, and a current measurement module 146. The voltage regulating module 142 is connected to the power supply 141 and is used to regulate the voltage of the electrode 144. The support plate 143 supports the test piece 11. The electrode 144 is connected to the voltage regulating module 142. The voltage measurement module 145 is connected to the electrode 144, and the current measurement module 146 is connected to the electrode 144.

[0043] The power supply 141 has a voltage of 220V and a frequency of 50Hz. A transformer 147 is provided between the voltage regulating module 142 and the electrode 144. The transformer 147 is used to increase the output voltage of the voltage regulating module 142.

[0044] Step c specifically involves:

[0045] Step d: Place the test piece 11 on the support plate 143. The power supply 141 applies voltage to the electrode 144 through the adjustment module and the transformer 147 in sequence. The electrode 144 is connected to both ends of the test piece 11 and applies a test voltage to the test piece 11. Then, the test voltage is increased uniformly through the voltage adjustment module 142 until the test piece 11 flashes over. The voltage value of the test voltage when the test piece 11 flashes over is obtained and recorded through the voltage measurement module 145. The peak value and image of the leakage current during the flashover process of the test piece 11 are obtained and recorded through the current measurement module 146.

[0046] Step e: Repeat step d four times;

[0047] Step f: Calculate the arithmetic mean of the test voltage values ​​of the test piece 11 during flashover obtained in five steps d, i.e., the flashover voltage;

[0048] Step g: Based on steps d to f, obtain the flashover voltage of all test pieces 11, the peak value of the leakage current when the test piece 11 flashes over, and the image.

[0049] In one implementation, electrode 144 is U-shaped and includes two extensions 1441 and a bent portion 1442 located between the extensions 1441. During step d, the window pane device 13 is placed on the support plate 143. The end of the extension 1441 away from the bent portion 1442 is fixedly connected to the first adjusting groove 1311 via the second connector 1443. Electrode 144 is positioned between the second adjusting rods 132, with each rod abutting against the electrode 144. The bent portion 1442 abuts against the test piece 11, thereby improving the stability of electrode 144. The curved shape of the bent portion 1442 allows for better contact between the electrode 144 and the test piece 11.

[0050] In one implementation, electrode 144 includes a first electrode 144 and a second electrode 144. Voltage regulating module 142 includes a positive terminal 1421 and a negative terminal 1422. The first electrode 144 is connected to the positive terminal 1421, and the second electrode 144 is connected to the negative terminal 1422. A loop is formed between the first electrode 144, the second electrode 144, and the voltage regulating module 142. The loop is equipped with a protective resistor 148 and a voltage divider module 149. The voltage divider module 149 can be configured as a capacitive voltage divider. One end of the voltage divider module 149 is connected to the first electrode 144, and the other end is grounded. The voltage divider module 149 is used to make the test voltage applied by the first electrode 144 to the test piece 11 more stable. Voltage measurement module 145 is connected to the first electrode 144 and is used to measure the voltage across the test piece 11. Current measurement module 146 is connected to the second electrode 144 and is used to measure the current flowing through the test piece 11.

[0051] During step d, the first electrode 144 is connected to one of the first adjusting rods 131, the second electrode 144 is connected to the other first adjusting rod 131, and the test piece 11 is located between the first electrode 144 and the second electrode 144. One end of the test piece 11 is connected to the first electrode 144, and the other end of the test piece 11 is connected to the second electrode 144.

[0052] During step c, the test piece is placed in an environment with constant temperature and humidity, which makes the experimental results more stable. Specifically, a temperature and humidity regulator can be placed near the test piece.

[0053] In one implementation, container 12 includes a receiving portion 121, a first connecting pipe 122, and a second connecting pipe 123. Both the first connecting pipe 122 and the second connecting pipe 123 are connected to the receiving portion 121. Specifically, the first connecting pipe 122, the second connecting pipe 123, and the receiving portion 121 are integrally formed. The first connecting pipe 122 is provided with a valve 1221, and the second connecting pipe 123 is provided with a sealing element 1231, which is used to block the second connecting pipe 123. During step b, the sealing element 1231 blocks the second connecting pipe 123, the valve 1221 is opened, and a vacuum pump is connected to the first connecting pipe 122 to evacuate the air from the container 12. Then, the valve 1221 is closed. At this point, there is no oxygen in the container 12, and the experimental sample in the container 12 is then immersed in a chemical cleaning agent.

[0054] In one implementation, the seal 1231 includes an insert 1231a, which is at least partially disposed within the second connecting tube 123. A first sealing ring is disposed between the insert 1231a and the second connecting tube 123 to improve the sealing performance between the insert 1231a and the second connecting tube 123. The insert 1231a is provided with an annular protrusion 1231b, and a second sealing ring is disposed between the annular protrusion 1231b and the second connecting tube 123. When the air pressure inside the container 12 decreases, the annular protrusion 1231b and the second connecting tube 123 clamp the second sealing ring, ensuring the sealing performance between the annular protrusion 1231b and the second connecting tube 123. The insert 1231a is provided with a rotating groove 1231c, which includes a first end and a second end. The first end communicates with the receiving portion 121, and the second end communicates with the atmosphere. From the first end to the second end, the inner diameter of the rotating groove 1231c gradually increases. The sealing element 1231 also includes a rotating body 1231d, which is at least partially rotatably connected within a rotating groove 1231c. A third sealing ring is provided between the rotating body 1231d and the rotating groove 1231c. When the air pressure inside the container 12 decreases, the rotating body 1231d and the rotating groove 1231c clamp the third sealing ring, thereby improving the sealing performance between the rotating groove 1231c and the rotating body 1231d. A winding wheel 1231e is rotatably connected within the insert 1231a. A wire groove is provided on the side of the insert 1231a near the receiving portion 121, and a pull wire 1231f is connected to the winding wheel 1231e, passing through the wire groove. A transmission assembly 1231g is provided between the winding wheel 1231e and the rotating body 1231d, enabling transmission between the winding wheel 1231e and the rotating body 1231d. A connection hole is provided on the experimental specimen. The end of the pull wire 1231f away from the winding wheel 1231e is connected to the connection hole, thereby connecting the pull wire 1231f and the experimental specimen together.

[0055] During step b, the experimental specimen is positioned above the chemical cleaning agent. One end of the pull wire 1231f is wound around the winding wheel 1231e. Valve 1221 is opened, and the vacuum pump operates to remove air from container 12. Then, valve 1221 is closed, and rotating body 1231d is rotated. Under the action of transmission component 1231g, winding wheel 1231e rotates, and pull wire 1231f is released from winding wheel 1231e. The experimental specimen moves towards and is immersed in the chemical cleaning agent. After the immersion time is up, rotating body 1231d is rotated, winding wheel 1231e winds pull wire 1231f, and the experimental specimen leaves the chemical cleaning agent. Then, valve 1221 is opened, atmospheric pressure is restored inside container 12, and then seal 1231 is pulled out, removing the experimental specimen from container 12.

[0056] In one implementation, the rotating body 1231d includes a first rotating part 1231h and a second rotating part 1231k. Both the first rotating part 1231h and the second rotating part 1231k are disposed in the rotating groove 1231c. The first rotating part 1231h is disposed on the side of the second rotating part 1231k near the receiving part 121. The first rotating part 1231h and the rotating groove 1231c are adapted to each other. The second rotating part 1231k and the rotating groove 1231c are adapted to each other. A transmission rod 1231m is fixedly connected to the side of the first rotating part 1231h near the second rotating part 1231k. The second rotating part 1231k is provided with a transmission groove 1231n. The transmission rod 1231m passes through the transmission groove 1231n and is rotatably connected to the transmission groove 1231n. A fourth sealing ring is provided between the transmission rod 1231m and the transmission groove 1231n to ensure the sealing between the transmission rod 1231m and the transmission groove 1231n. A fifth sealing ring is provided between the second rotating part 1231k and the rotating groove 1231c to ensure the sealing between the second rotating part 1231k and the transmission groove 1231n. A pressing block 1231s is provided at the end of the transmission rod 1231m away from the first rotating part 1231h. The pressing block 1231s abuts against the side of the second rotating part 1231k away from the first rotating part 1231h, and is used to press the second rotating part 1231k tightly against the wall of the rotating groove 1231c. When it is necessary to rotate the winding wheel 1231e, only the transmission rod 1231m needs to be rotated.

[0057] In one implementation, the transmission assembly 1231g includes a driven bevel gear 1231p fixedly connected to the winding wheel 1231e and a drive bevel gear 1231r fixedly connected to the first rotating part 1231h, wherein the driven bevel gear 1231p and the drive bevel gear 1231r mesh.

[0058] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A method for conducting a surface flashover test on an insulator test piece, characterized in that, The test pieces include control test pieces and experimental test pieces. The test pieces have the same structure. There are two or more experimental test pieces. The specific steps of the experimental method are as follows: Step a: Immerse the test pieces in their respective chemical cleaning agents, gradually increasing the immersion time for each test piece; Step b: Prepare artificial dirt and use it to coat the test pieces. After coating, the salt density and ash density of each test piece are equal. Step c: Use the testing device to obtain and record the flashover voltage of each test piece and the leakage current when the test piece flashes over; Step c specifically involves: Step d: Place the test piece on the support plate, connect the electrodes to both ends of the test piece and apply a test voltage to the test piece. Then, increase the test voltage uniformly through the voltage adjustment module until the test piece flashes over. Obtain and record the voltage value of the test voltage when the test piece flashes over through the voltage measurement module. Obtain and record the peak value and image of the leakage current during the flashover process of the test piece through the current measurement module. Step e: Repeat step d four times; Step f: Calculate the arithmetic mean of the test voltage values ​​measured in five steps d when the test piece flashes over, i.e., the flashover voltage; Step g: Based on steps d to f, obtain the flashover voltage of all test pieces, the peak value of the leakage current when the test piece flashes over, and the image. In step b, the test piece is coated with a window pane device. The window pane device includes two parallel first adjusting rods and two parallel second adjusting rods. A rectangular window is formed between the first adjusting rods and the second adjusting rods. The first adjusting rods are provided with a first adjusting groove, and the second adjusting rods are provided with a second adjusting groove. The first adjusting rods and the second adjusting rods are fixedly connected together by a first connecting member, which passes through the first adjusting groove and the second adjusting groove. When applying stain to the test piece, first adjust the size of the window of the window pane device according to the area to be stained. Then, fix the first adjusting rod and the second adjusting groove together through the first connector. Place the test piece under the window pane device and use a dropper to drip artificial dirt onto the test piece through the window. The electrode is U-shaped and includes two extensions and a bent portion between the extensions. During step d, the window pane device is placed on the support plate. The end of the extension away from the bent portion is fixedly connected to the first adjustment groove through the second connector. The electrode is arranged between the second adjustment rods, and the second adjustment rods abut against the electrode. The bent portion abuts against the test piece.

2. A method for surface flashover testing of an insulator specimen according to claim 1, characterized in that, The chemical cleaning agent is placed in a container, and the oxygen in the container is purged before proceeding to step a.

3. A method for surface flashover testing of an insulator specimen according to claim 1, characterized in that, The testing device includes a power supply, a voltage regulating module, a support plate, electrodes, a voltage measurement module, and a current measurement module. The voltage regulating module is connected to the power supply, the support plate is used to support the test piece, the electrodes are connected to the voltage regulating module, the voltage measurement module is connected to the electrodes, and the current measurement module is connected to the electrodes.

4. A method for surface flashover testing of an insulator specimen according to claim 1, characterized in that, The electrode includes a first electrode and a second electrode. The voltage regulating module includes a positive terminal and a negative terminal. The first electrode is connected to the positive terminal, and the second electrode is connected to the negative terminal. A loop is formed between the first electrode, the second electrode, and the voltage regulating module. The loop is equipped with a protective resistor and a voltage divider module. One end of the voltage divider module is connected to the first electrode, and the other end of the voltage divider module is grounded. The voltage measurement module is connected to the first electrode, and the current measurement module is connected to the second electrode.

5. A method for surface flashover testing of an insulator specimen according to claim 2, characterized in that, The container includes a receiving part, a first connecting pipe, and a second connecting pipe. Both the first and second connecting pipes are connected to the receiving part. The first connecting pipe is equipped with a valve, and the second connecting pipe is equipped with a sealing element. The sealing element includes an insert, which is at least partially disposed within the second connecting pipe. A first sealing ring is disposed between the insert and the second connecting pipe. The insert has an annular protrusion, and a second sealing ring is disposed between the annular protrusion and the second connecting pipe. The insert has a rotating groove, which includes a first end and a second end. The first end is connected to the receiving part, and the second end is connected to the atmosphere. The inner diameter of the rotating groove gradually increases from the first end to the second end. The sealing element also includes a rotating body, which is at least partially rotatably connected within the rotating groove. A third sealing ring is disposed between the rotating body and the rotating groove. A winding wheel is rotatably connected within the insert. A wire groove is disposed on the side of the insert near the receiving part. A pull wire is connected to the winding wheel and passes through the wire groove. A transmission assembly is disposed between the winding wheel and the rotating body.

6. A method for surface flashover testing of an insulator specimen according to claim 5, characterized in that, The rotating body includes a first rotating part and a second rotating part, both of which are disposed within a rotating groove. The first rotating part is disposed on the side of the second rotating part near the receiving part. The first rotating part and the rotating groove are adapted to each other. A transmission rod is fixedly connected to the side of the first rotating part near the second rotating part. The second rotating part is provided with a transmission groove. The transmission rod passes through the transmission groove and is rotatably connected to the transmission groove. A fourth sealing ring is provided between the transmission rod and the transmission groove. A fifth sealing ring is provided between the second rotating part and the rotating groove. A pressing block is provided at the end of the transmission rod away from the first rotating part. The pressing block abuts against the side of the second rotating part away from the first rotating part.

7. A method for conducting a surface flashover test on an insulator specimen according to claim 6, characterized in that, The transmission assembly includes a driven bevel gear fixedly connected to the winding wheel and a drive bevel gear fixedly connected to the first rotating part, wherein the driven bevel gear and the drive bevel gear mesh.

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