Insulating material flashover experiment device and method for measuring flashover voltage and initial voltage

Abstract

The invention discloses an insulating material flashover experiment device and method for measuring flashover voltage and initial voltage. The device comprises a metal tank body, an insulator upper cover, an insulating sample piece, a charge injection assembly, a charge measurement assembly, a surface flashover assembly, a sample piece bearing assembly and a flashover voltage and initial voltage measurement assembly. The flashover voltage and initial voltage measuring assembly is assembled on the insulating sealing cover of the metal tank body; the sample piece bearing assembly is arranged on the surface flashover experiment assembly; and the insulating sample piece is arranged on the sample piece bearing assembly. By adopting the insulating material flashover experimental device for measuring the flashover voltage and the initial voltage, the flashover voltage and the initial voltage along the surface of the insulating sample piece can be measured, the supporting form of the insulating sample piece is optimized, the research range of the device is widened, and the working efficiency of the device is improved. Through an insulating material surface flashover experiment, change characteristics of insulating medium surface flashover characteristics are determined, so that effective theoretical guidance is provided for insulation optimization design of the basin-type insulator.

Description

Technical Field

[0001] The invention belongs to the technical field of electrical experiments, and in particular relates to an insulating material flashover experiment device and method for measuring flashover voltage and starting voltage. Background Art

[0002] In the power system, the large-scale application of AC gas-insulated metal-enclosed switchgear (GIS) and gas-insulated transmission lines (GIL) has effectively promoted the development of miniaturization and gas insulation of power equipment. However, due to the problem of surface flashover of basin-type insulators caused by charge accumulation, AC gas-insulated metal-enclosed switchgear (GIS) and gas-insulated transmission lines (GIL) have failed to make substantial breakthroughs for a long time, and their industrial application still faces difficulties.

[0003] Therefore, studying the influence of surface charge on the surface flashover characteristics of insulating media under the action of DC electric field is of great significance to promote the industrial application of AC gas-insulated metal-enclosed switchgear (GIS) and gas-insulated transmission lines (GIL).

[0004] The accumulation of charge at the gas-solid interface is an important factor leading to insulation breakdown. It will aggravate the electric field distortion in the local area of ​​the solid medium surface, and then ionize more free charges, providing conditions for flashover, which will cause high-voltage equipment to fail or even burn out.

[0005] At present, in the existing related research, the surface charge density of the insulating material is mainly measured as a research method. There is a lack of quantitative research on the surface flashover characteristics of the insulator after the surface charge accumulates. Under the action of the surface charge, the changing characteristics of the surface flashover characteristics of the insulating medium are still unclear. Through the existing research methods, it is impossible to construct the correlation characteristics between the charge accumulation on the surface of the insulating material and the surface flashover, and it is also impossible to provide effective theoretical guidance for the insulation optimization design of the basin insulator.

[0006] To this end, a Chinese patent application with patent application number 202311256645.7 discloses a device and method for surface charge injection, measurement and surface flashover experiment of insulating materials. The scheme can complete the charge injection on the surface of the insulating material, and at the same time can measure the charge density on the surface of the insulating material. Under the action of the surface charge, the surface flashover experiment of the insulating material can be further realized. The changing characteristics of the surface flashover characteristics of the insulating medium are clarified through experiments, and then the correlation characteristics between the charge accumulation on the surface of the insulating material and the surface flashover can be constructed, which can provide effective theoretical guidance for the insulation optimization design of pot-type insulators.

[0007] However, when the above scheme is adopted, the device lacks the ability to measure the surface flashover voltage and starting voltage of the insulating sample piece. At the same time, the device does not give sufficient consideration to the support form of the insulating sample piece, thereby limiting the research scope of the device. Summary of the invention

[0008] In view of the problems existing in the prior art, the present invention provides an insulating material flashover experimental device and method for measuring the flashover voltage and the starting voltage, which has the ability to measure the surface flashover voltage and the starting voltage of the insulating sample piece, optimizes the supporting form of the insulating sample piece, and broadens the research scope of the device.

[0009] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: an insulating material flashover experimental device for measuring flashover voltage and starting voltage, comprising a metal tank body, an insulator upper cover, an insulating sample piece, a charge injection component, a charge measurement component, a surface flashover component, a sample piece supporting component and a flashover voltage and starting voltage measurement component; the insulator upper cover sealing buckle is installed at the upper tank mouth of the metal tank body, four openings are arranged circumferentially in the middle of the side plate of the metal tank body, and the first insulating cover, the second insulating cover, the third insulating cover and the Observation window; the first insulating cover is used to be equipped with a charge injection component; the second insulating cover is used to be equipped with a charge measurement component; the third insulating cover is used to be equipped with a flashover voltage and starting voltage measurement component; a high-voltage guide rod is vertically fixed at the center of the insulator upper cover; the surface flashover component is installed between the high-voltage guide rod and the bottom plate of the metal tank body, an insulating gas injection port is provided on the bottom plate of the metal tank body, and the metal tank body is grounded through a wire; the sample piece supporting assembly is arranged on the surface flashover assembly; the insulating sample piece is arranged on the sample piece supporting assembly.

[0010] The insulating sample piece adopts a circular structure, and a plurality of measuring points are marked on the upper surface of the insulating sample piece.

[0011] The measuring points are distributed in a plurality of circles along the radial direction relative to the center of the insulating sample piece, and the measuring points on each circle are distributed at equal intervals along the circumferential direction.

[0012] The charge injection assembly includes a first DC power supply, a first resistor, a high-voltage guide post, a conductive spring, a first insulating support rod, a first metal support rod, a needle electrode and a first translation drive mechanism; the positive electrode of the first DC power supply is connected to one end of the first resistor through a wire, and the other end of the first resistor is connected to the high-voltage guide post through a wire, the high-voltage guide post is horizontally fixedly installed on the first insulating cover, one end of the high-voltage guide post is located outside the metal tank body, and the other end of the high-voltage guide post is located inside the metal tank body; the negative electrode of the first DC power supply is grounded through a wire; the first insulating support rod is coaxially fixed to the first metal support rod The invention relates to a combined support rod, which is horizontally sealed and passes through a first insulating cover. The combined support rod has axial freedom of movement relative to the first insulating cover. One end of the first metal support rod in the combined support rod always extends into the interior of the metal tank body. The needle electrode is vertically fixed to the end of the first metal support rod located inside the metal tank body. One end of the conductive spring sheet is fixed to the end of the high-voltage guide column located inside the metal tank body, and the other end of the conductive spring sheet overlaps and conducts with the first metal support rod. The first translation drive mechanism is located outside the metal tank body, and the first insulating support rod in the combined support rod is connected to the first translation drive mechanism.

[0013] The charge measurement component includes an electrostatic probe, a second insulating support rod and a second translation drive mechanism; the second insulating support rod is horizontally sealed and passes through the second insulating cover, and the second insulating support rod has axial movement freedom relative to the second insulating cover; the electrostatic probe is vertically fixed on the end of the second insulating support rod located inside the metal tank body; the second translation drive mechanism is located outside the metal tank body, and the other end of the second insulating support rod is connected to the second translation drive mechanism.

[0014] The surface flashover assembly includes a second DC power supply, a second resistor, an electrode plate, a second metal support rod, an insulating support plate, an insulating bracket, a first finger-shaped electrode, a second finger-shaped electrode, a lifting drive mechanism and a rotating drive mechanism; the positive electrode of the second DC power supply is connected to one end of the second resistor through a wire, and the other end of the second resistor is connected to the high-voltage guide rod at the center of the insulator cover through a wire; the second metal support rod vertically seals and passes through the bottom plate of the metal tank body, and the second metal support rod has axial freedom of movement relative to the bottom plate of the metal tank body; the electrode plate is horizontally fixed on the top of the second metal support rod, and the insulating sample piece is horizontally fixed on the upper surface of the electrode plate; the insulating support The support plate is horizontally arranged directly above the insulating sample piece, and the insulating support plate is fixedly connected to the bottom plate of the metal tank body through an insulating bracket; the first finger-shaped electrode and the second finger-shaped electrode are fixedly installed in parallel on the edge of the lower surface of the insulating support plate, the first finger-shaped electrode is connected to the high-voltage guide rod through a wire, the second finger-shaped electrode is connected to the metal tank body through a wire, and the second finger-shaped electrode is grounded through the metal tank body; the lifting drive mechanism and the rotary drive mechanism are located outside the metal tank body, the rotary drive mechanism is installed on the lifting drive mechanism, and the lower end of the second metal support rod is connected to the rotary drive mechanism; the electrode plate is grounded through the second metal support rod and the metal tank body in turn.

[0015] The specimen support assembly comprises an insulating support plate, a metal support barrel, a metal floating support plate, a guide stud, a buffer support spring and a limit nut; the insulating support plate is horizontally arranged directly below the electrode plate, and the insulating support plate is fixedly connected to the insulating bracket; a circular opening is provided at the center of the insulating support plate, and the metal support barrel is fixedly installed in the circular opening at the center of the insulating support plate; the metal floating support plate is horizontally arranged inside the metal support barrel, and guide holes are uniformly opened along the circumference on the bottom plate of the metal support barrel, and the guide studs are arranged along the circumference. The metal support barrel is evenly fixed on the lower surface of the metal floating support plate, the guide stud extends through the guide hole to the bottom of the metal support barrel, and the limit nut is threadedly sleeved on the guide stud located under the bottom of the metal support barrel; the buffer support spring is sleeved on the guide stud between the metal floating support plate and the bottom of the metal support barrel; a through hole for the second metal support rod is opened in the center of the metal floating support plate and the center of the bottom of the metal support barrel; the metal support barrel is connected to the metal tank body through a wire, and the metal support barrel is grounded through the metal tank body.

[0016] The flashover voltage and starting voltage measurement component includes a photomultiplier tube, an amplifier, an oscilloscope, a voltage divider and a voltage divider box; the photomultiplier tube is horizontally sealed and passes through a third insulating cover, the measuring end of the photomultiplier tube is located inside the metal tank body, and the signal output end of the photomultiplier tube is electrically connected to the oscilloscope through the amplifier; the voltage divider is arranged in parallel with the metal tank body, and the voltage divider is electrically connected to the oscilloscope through the voltage divider box.

[0017] An insulating material flashover test method, using the insulating material flashover test device for measuring the flashover voltage and the starting voltage, comprises the following steps:

[0018] Step 1: Open the observation window, and insert the insulating sample into the metal tank through the observation window until the insulating sample is placed on the flush upper surface of the electrode plate and the metal support barrel, and then close the observation window;

[0019] Step 2: Fill the metal tank with insulating gas through the insulating gas injection port until the gas pressure reaches a set value, and then close the insulating gas injection port;

[0020] Step 3: Start the first translation driving mechanism to drive the combined support rod composed of the first insulating support rod and the first metal support rod to move into the metal can body until the needle electrode is driven to move to the top of the center of the insulating sample piece;

[0021] Step 4: starting the first DC power supply, applying a voltage between the needle electrode and the electrode plate, the voltage application time is 10 to 30 minutes, until the charge injection is completed on the surface of the insulating sample piece, and then turning off the first DC power supply;

[0022] Step 5: Reversely start the first translation driving mechanism to drive the combined support rod composed of the first insulating support rod and the first metal support rod to move toward the outside of the metal can body until the needle electrode is driven to leave from above the insulating sample piece and move back to the initial position;

[0023] Step 6: Start the second translation drive mechanism to drive the second insulating support rod to move into the metal tank until the electrostatic probe is driven to move to the top of the center of the insulating sample piece;

[0024] Step 7: Start the second translation drive mechanism in reverse to drive the electrostatic probe to move from the center of the insulating sample piece to the location of the first inner circle measurement point, then start the rotary drive mechanism to drive the second metal support rod, the electrode plate and the insulating sample piece to rotate synchronously, and complete the charge measurement of the first inner circle measurement point through the electrostatic probe;

[0025] Step 8: Repeat step 7, and complete the charge measurement of all measurement points from the inside to the outside in accordance with the charge measurement process of the first circle of measurement points on the inner side of the insulating sample piece;

[0026] Step 9: After the charge measurement of the first circle of measurement points outside the insulating sample piece is completed, the second translation drive mechanism is started in the reverse direction to drive the second insulating support rod to move toward the outside of the metal tank until the electrostatic probe leaves the insulating sample piece and moves back to the initial position;

[0027] Step 10: Start the lifting drive mechanism to drive the second metal support rod, the electrode plate and the insulating sample piece to rise synchronously until the insulating sample piece contacts the first finger-shaped electrode and the second finger-shaped electrode; at the same time, under the thrust of the buffer support spring, the metal floating support plate and the guide stud also rise synchronously until the limit nut abuts against the bottom plate of the metal support barrel;

[0028] Step 11: Start the second DC power supply and apply voltage to the first finger-shaped electrode and the second finger-shaped electrode until a surface flashover phenomenon occurs;

[0029] Step 12: Shield the observation window from light to prevent external light from entering the metal tank body, so that only flash light signals and corona light signals are visible inside the metal tank body;

[0030] Step 13: Enable the photomultiplier tube, collect the flashover light signal and the corona light signal through the photomultiplier tube, then output the electrical signal from the photomultiplier tube, and further transmit it to the oscilloscope through the amplifier. At the same time, with the cooperation of the voltage divider and the voltage divider box, the flashover voltage and the starting voltage are displayed in real time on the oscilloscope;

[0031] Step 14: Turn off the second DC power supply, start the lifting drive mechanism in reverse, drive the second metal support rod, the electrode plate and the insulating sample piece to descend synchronously, and the insulating sample piece is separated from the first finger-shaped electrode and the second finger-shaped electrode until the electrode plate contacts the metal floating support plate, the buffer support spring is compressed, the metal floating support plate and the guide stud descend synchronously, and the limit nut is separated from the barrel bottom plate of the metal support barrel, so that the electrode plate and the upper surface of the metal support barrel are restored to a flush state.

[0032] Beneficial effects of the present invention:

[0033] The insulating material flashover experimental device and method for measuring flashover voltage and starting voltage of the present invention have the ability to measure the surface flashover voltage and starting voltage of the insulating sample piece, optimize the supporting form of the insulating sample piece, and broaden the research scope of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a structural schematic diagram of the insulating material flashover experimental device (initial state) for measuring the flashover voltage and the starting voltage of the present invention (viewing angle 1, overall);

[0035] Figure 2 It is a structural schematic diagram of the insulating material flashover experimental device (initial state) for measuring the flashover voltage and the starting voltage of the present invention (viewing angle 2, partial);

[0036] Figure 3 It is a structural schematic diagram of the insulating material flashover experimental device (charge injection) for measuring the flashover voltage and the starting voltage of the present invention (viewing angle 1, overall);

[0037] Figure 4 It is a structural schematic diagram of the insulating material flashover experimental device (charge measurement) for measuring the flashover voltage and the starting voltage of the present invention (viewing angle 1, overall);

[0038] Figure 5 It is a structural schematic diagram of the insulating material flashover experimental device (surface flashover) for measuring the flashover voltage and the starting voltage of the present invention (viewing angle 1, overall);

[0039] Figure 6 It is a structural schematic diagram of the insulating material flashover experimental device (flashover voltage and starting voltage measurement) for measuring the flashover voltage and starting voltage of the present invention (viewing angle 2, partial);

[0040] In the figure, 1 is a metal tank, 2 is an insulator cover, 3 is an insulating sample piece, 4 is a first insulating cover, 5 is a second insulating cover, 6 is a third insulating cover, 7 is an observation window, 8 is a high-voltage guide rod, 9 is an insulating gas injection port, 10 is a first DC power supply, 11 is a first resistor, 12 is a high-voltage guide column, 13 is a conductive spring sheet, 14 is a first insulating support rod, 15 is a first metal support rod, 16 is a needle electrode, 17 is a first translation drive mechanism, 18 is an electrostatic probe, 19 is a second insulating support rod, 20 is a second translation drive mechanism, 21 is a —second DC power supply, 22—second resistor, 23—electrode plate, 24—second metal support rod, 25—insulating support plate, 26—insulating bracket, 27—first finger-shaped electrode, 28—second finger-shaped electrode, 29—lifting drive mechanism, 30—rotating drive mechanism, 31—insulating support plate, 32—metal support barrel, 33—metal floating support plate, 34—guide stud, 35—buffer support spring, 36—limit nut, 37—photomultiplier tube, 38—amplifier, 39—oscilloscope, 40—voltage divider, 41—voltage divider box. DETAILED DESCRIPTION

[0041] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0042] like Figures 1 to 6As shown, an insulating material flashover experimental device for measuring flashover voltage and starting voltage comprises a metal tank body 1, an insulator upper cover 2, an insulating sample piece 3, a charge injection component, a charge measurement component, a surface flashover component, a sample piece supporting component and a flashover voltage and starting voltage measurement component; the insulator upper cover 2 is sealed and mounted at the upper tank mouth of the metal tank body 1, and four openings are arranged circumferentially in the middle of the side plate of the metal tank body 1, and the first insulating cover 4, the second insulating cover 5, the third insulating cover 6 and the observation window 7 are respectively fixed on the four openings; the first insulating cover 2 is sealed and mounted at the upper tank mouth of the metal tank body 1, and the second insulating cover 5, the third insulating cover 6 and the observation window 7 are respectively fixed on the first insulating cover 2; ... The edge cover 4 is used to fit the charge injection component; the second insulating cover 5 is used to fit the charge measurement component; the third insulating cover 6 is used to fit the flashover voltage and starting voltage measurement component; a high-voltage conductor 8 is vertically fixed at the center of the insulator upper cover 2; the surface flashover component is fitted between the high-voltage conductor 8 and the bottom plate of the metal tank body 1, and an insulating gas injection port 9 is provided on the bottom plate of the metal tank body 1, and the metal tank body 1 is grounded through a wire; the sample piece supporting assembly is arranged on the surface flashover assembly; the insulating sample piece 3 is arranged on the sample piece supporting assembly.

[0043] The insulating sample piece 3 has a circular structure, and a plurality of measuring points are marked on the upper surface of the insulating sample piece 3 .

[0044] The measuring points are distributed in multiple circles along the radial direction relative to the center of the insulating sample piece 3, and the measuring points on each circle are distributed at equal intervals along the circumferential direction.

[0045] The charge injection assembly includes a first DC power supply 10, a first resistor 11, a high-voltage guide post 12, a conductive spring 13, a first insulating support rod 14, a first metal support rod 15, a needle electrode 16 and a first translation drive mechanism 17; the positive electrode of the first DC power supply 10 is connected to one end of the first resistor 11 through a wire, and the other end of the first resistor 11 is connected to the high-voltage guide post 12 through a wire, the high-voltage guide post 12 is horizontally fixedly installed on the first insulating cover 4, one end of the high-voltage guide post 12 is located outside the metal tank body 1, and the other end of the high-voltage guide post 12 is located inside the metal tank body 1; the negative electrode of the first DC power supply 10 is grounded through a wire; the first insulating support rod 14 and the first metal support rod 15 are connected to the first metal support rod 16; the positive electrode of the first DC power supply 10 is connected to the first end of the first resistor 11 through a wire, and the other end of the first resistor 11 is connected to the high-voltage guide post 12 through a wire; the high-voltage guide post 12 is horizontally fixedly installed on the first insulating cover 4, and the high-voltage guide post 12 is located outside the metal tank body 1, and the other end of the high-voltage guide post 12 is located inside the metal tank body 1; the negative electrode of the first DC power supply 10 is grounded through a wire; the first insulating support rod 14 and the first metal support rod 15 are connected to the first metal support rod 16; the positive electrode of the first DC power supply 10 is connected to the first end of the first resistor 11 through a wire; the first end of the first resistor 11 is connected to the first metal support rod 15; the first end of the first resistor 11 is connected to the first metal support rod 15; the first end of the first resistor 11 is connected to the first metal support rod 15; the The rod 15 is coaxially fixed to form a combined support rod, which horizontally seals and passes through the first insulating cover 4. The combined support rod has axial freedom of movement relative to the first insulating cover 4, and one end of the first metal support rod 15 in the combined support rod always extends into the interior of the metal tank body 1; the needle electrode 16 is vertically fixed to the end of the first metal support rod 15 located inside the metal tank body 1; one end of the conductive spring sheet 13 is fixed to the end of the high-voltage guide column 12 located inside the metal tank body 1, and the other end of the conductive spring sheet 13 overlaps and conducts with the first metal support rod 15; the first translation drive mechanism 17 is located outside the metal tank body 1, and the first insulating support rod 14 in the combined support rod is connected to the first translation drive mechanism 17.

[0046] The charge measurement component includes an electrostatic probe 18, a second insulating support rod 19 and a second translation drive mechanism 20; the second insulating support rod 19 is horizontally sealed and passes through the second insulating cover 5, and the second insulating support rod 19 has axial movement freedom relative to the second insulating cover 5; the electrostatic probe 18 is vertically fixed on the end of the second insulating support rod 19 located inside the metal tank body 1; the second translation drive mechanism 20 is located outside the metal tank body 1, and the other end of the second insulating support rod 19 is connected to the second translation drive mechanism 20.

[0047] The surface flashover assembly includes a second DC power supply 21, a second resistor 22, an electrode plate 23, a second metal support rod 24, an insulating support plate 25, an insulating bracket 26, a first finger-shaped electrode 27, a second finger-shaped electrode 28, a lifting drive mechanism 29 and a rotary drive mechanism 30; the positive electrode of the second DC power supply 21 is connected to one end of the second resistor 22 through a wire, and the other end of the second resistor 22 is connected to the high-voltage guide rod 8 at the center of the insulator cover 2 through a wire; the second metal support rod 24 vertically seals and passes through the bottom plate of the metal tank body 1, and the second metal support rod 24 has axial movement freedom relative to the bottom plate of the metal tank body 1; the electrode plate 23 is horizontally fixed on the top of the second metal support rod 24, and the insulating sample piece 3 is horizontally fixed on the upper surface of the electrode plate 23; the insulating support The support plate 25 is horizontally arranged just above the insulating sample piece 3, and the insulating support plate 25 is fixedly connected to the bottom plate of the metal tank body 1 through the insulating bracket 26; the first finger-shaped electrode 27 and the second finger-shaped electrode 28 are fixedly installed in parallel on the edge of the lower surface of the insulating support plate 25, the first finger-shaped electrode 27 is connected to the high-voltage guide rod 8 through a wire, and the second finger-shaped electrode 28 is connected to the metal tank body 1 through a wire, and the second finger-shaped electrode 28 is grounded through the metal tank body 1; the lifting drive mechanism 29 and the rotary drive mechanism 30 are located outside the metal tank body 1, the rotary drive mechanism 30 is installed on the lifting drive mechanism 29, and the lower end of the second metal support rod 24 is connected to the rotary drive mechanism 30; the electrode plate 23 is grounded through the second metal support rod 24 and the metal tank body 1 in turn.

[0048] The specimen support assembly includes an insulating support plate 31, a metal support barrel 32, a metal floating support plate 33, a guide stud 34, a buffer support spring 35 and a limit nut 36; the insulating support plate 31 is horizontally arranged directly below the electrode plate 23, and the insulating support plate 31 is fixedly connected to the insulating bracket 26; a circular opening is provided at the center of the insulating support plate 31, and the metal support barrel 32 is fixedly installed in the circular opening at the center of the insulating support plate 31; the metal floating support plate 33 is horizontally arranged inside the metal support barrel 32, and guide holes are uniformly opened along the circumferential direction on the bottom plate of the metal support barrel 32, and the guide stud 34 is arranged along the The guide studs 34 are evenly fixed on the lower surface of the metal floating support plate 33 in the circumferential direction, and extend to the bottom of the bottom plate of the metal support barrel 32 through the guide holes. The limit nuts 36 are screwed and sleeved on the guide studs 34 located under the bottom plate of the metal support barrel 32. The buffer support spring 35 is sleeved on the guide studs 34 between the metal floating support plate 33 and the bottom plate of the metal support barrel 32. The second metal support rod 24 has a through hole at the center of the metal floating support plate 33 and the center of the bottom plate of the metal support barrel 32. The metal support barrel 32 is connected to the metal tank body 1 through a wire, and the metal support barrel 32 is grounded through the metal tank body 1.

[0049] The flashover voltage and starting voltage measurement component includes a photomultiplier tube 37, an amplifier 38, an oscilloscope 39, a voltage divider 40 and a voltage divider box 41; the photomultiplier tube 37 is horizontally sealed and passes through the third insulating cover 6, the measuring end of the photomultiplier tube 37 is located inside the metal tank body 1, and the signal output end of the photomultiplier tube 37 is electrically connected to the oscilloscope 39 through the amplifier 38; the voltage divider 40 is arranged in parallel with the metal tank body 1, and the voltage divider 40 is electrically connected to the oscilloscope 39 through the voltage divider box 41.

[0050] In this embodiment, the first translation drive mechanism 17, the second translation drive mechanism 20 and the lifting drive mechanism 29 all adopt motor-driven nut slider guide mechanisms, and the rotary drive mechanism 30 directly adopts an electric motor; a total of 29 circles of measuring points are arranged on the upper surface of the insulating sample piece 3, and the number of measuring points on each circle is 80, so that the total number of measuring points on the upper surface of the insulating sample piece 3 is 2320.

[0051] An insulating material flashover test method, using the insulating material flashover test device for measuring the flashover voltage and the starting voltage, comprises the following steps:

[0052] Step 1: Open the observation window 7, and feed the insulating sample piece 3 into the metal can body 1 through the observation window 7 until the insulating sample piece 3 is placed on the flush upper surface of the electrode plate 23 and the metal support barrel 32, and then close the observation window 7;

[0053] Step 2: Fill the metal tank 1 with insulating gas through the insulating gas injection port 9 until the gas pressure reaches a set value, and then close the insulating gas injection port 9;

[0054] Step 3: Start the first translation driving mechanism 17 to drive the combined support rod composed of the first insulating support rod 14 and the first metal support rod 15 to move into the metal can body 1 until the needle electrode 16 is driven to move to the center of the insulating sample piece 3;

[0055] Step 4: Start the first DC power supply 10, apply voltage between the needle electrode 16 and the electrode plate 23, and apply the voltage for 10 to 30 minutes until the charge injection is completed on the surface of the insulating sample piece 3, and then turn off the first DC power supply 10;

[0056] Step 5: Reversely start the first translation driving mechanism 17 to drive the combined support rod composed of the first insulating support rod 14 and the first metal support rod 15 to move toward the outside of the metal can body 1, until the needle electrode 16 is driven to leave from above the insulating sample piece 3 and move back to the initial position;

[0057] Step 6: Start the second translation drive mechanism 20 to drive the second insulating support rod 19 to move into the metal can body 1 until the electrostatic probe 18 is driven to move to the center of the insulating sample piece 3;

[0058] Step 7: Reversely start the second translation drive mechanism 20 to drive the electrostatic probe 18 to move from the center of the insulating sample piece 3 to the position of the inner first circle measurement point, then start the rotary drive mechanism 30 to drive the second metal support rod 24, the electrode plate 23 and the insulating sample piece 3 to rotate synchronously, and complete the charge measurement of the inner first circle measurement point through the electrostatic probe 18;

[0059] Step 8: Repeat step 7, and complete the charge measurement of all measurement points from the inside to the outside in accordance with the charge measurement process of the first circle of measurement points on the inner side of the insulating sample piece 3;

[0060] Step nine: After the charge measurement of the first circle of measurement points outside the insulating sample piece 3 is completed, the second translation drive mechanism 20 is started in the reverse direction to drive the second insulating support rod 19 to move outside the metal can body 1 until the electrostatic probe 18 leaves the insulating sample piece 3 and moves back to the initial position;

[0061] Step 10: Start the lifting drive mechanism 29 to drive the second metal support rod 24, the electrode plate 23 and the insulating sample piece 3 to rise synchronously until the insulating sample piece 3 contacts the first finger-shaped electrode 27 and the second finger-shaped electrode 28; at the same time, under the thrust of the buffer support spring 35, the metal floating support plate 33 and the guide stud 34 also rise synchronously until the limit nut 36 abuts against the bottom plate of the metal support barrel 32;

[0062] Step 11: Start the second DC power supply 21 and apply voltage to the first finger-shaped electrode 27 and the second finger-shaped electrode 28 until a surface flashover phenomenon occurs;

[0063] Step 12: Shield the observation window 7 from light to prevent external light from entering the metal tank body 1, so that only the flash light signal and the corona light signal are visible inside the metal tank body 1;

[0064] Step 13: The photomultiplier tube 37 is activated, and the flashover light signal and the corona light signal are collected by the photomultiplier tube 37, and then the photomultiplier tube 37 outputs an electrical signal, which is further transmitted to the oscilloscope 39 through the amplifier 38. At the same time, with the cooperation of the voltage divider 40 and the voltage divider box 41, the flashover voltage and the starting voltage are displayed in real time in the oscilloscope 39;

[0065] Step 14: Turn off the second DC power supply 21, start the lifting drive mechanism 29 in reverse, drive the second metal support rod 24, the electrode plate 23 and the insulating sample piece 3 to descend synchronously, and the insulating sample piece 3 is separated from the first finger-shaped electrode 27 and the second finger-shaped electrode 28 until the electrode plate 23 contacts the metal floating support plate 33, the buffer support spring 35 is compressed, the metal floating support plate 33 and the guide stud 34 descend synchronously, and the limit nut 36 is separated from the barrel bottom plate of the metal support barrel 32, so that the electrode plate 23 and the upper surface of the metal support barrel 32 are restored to a flush state.

[0066] The above experimental process can be repeated according to experimental needs. The difference is that the type and pressure of the insulating gas filled into the metal tank body 1 can be adjusted to verify the influence of the insulating gas environment under different types and pressures on the surface flashover characteristics of the insulating medium.

[0067] The solutions in the embodiments are not intended to limit the protection scope of the present invention. All equivalent implementations or changes that do not deviate from the present invention are included in the protection scope of the present invention.

Claims

1. An insulating material flashover test device for measuring flashover voltage and starting voltage, characterized in that: It comprises a metal tank body, an insulator upper cover, an insulating sample piece, a charge injection component, a charge measurement component, a surface flashover component, a sample piece supporting component and a flashover voltage and starting voltage measurement component; the sealing buckle of the insulator upper cover is installed at the upper tank mouth of the metal tank body, and four openings are arranged circumferentially in the middle of the side plate of the metal tank body, and the first insulating cover, the second insulating cover, the third insulating cover and the observation window are respectively fixed on the four openings; the first insulating cover is used to fit the charge injection component; the second insulating cover is used to fit the charge measurement component; the third insulating cover is used to fit the flashover voltage and starting voltage measurement component; a high-voltage guide rod is vertically fixed at the center of the insulator upper cover; the surface flashover component is installed between the high-voltage guide rod and the bottom plate of the metal tank body, an insulating gas injection port is provided on the bottom plate of the metal tank body, and the metal tank body is grounded by a wire; the sample piece supporting component is arranged on the surface flashover component; the insulating sample piece is arranged on the sample piece supporting component.

2. The insulating material flashover test device for measuring the flashover voltage and the starting voltage according to claim 1, characterized in that: The insulating sample piece adopts a circular structure, and a plurality of measuring points are marked on the upper surface of the insulating sample piece.

3. The insulating material flashover test device for measuring the flashover voltage and the starting voltage according to claim 2, characterized in that: The measuring points are distributed in a plurality of circles along the radial direction relative to the center of the insulating sample piece, and the measuring points on each circle are distributed at equal intervals along the circumferential direction.

4. The insulating material flashover test device for measuring the flashover voltage and the starting voltage according to claim 1, characterized in that: The charge injection assembly includes a first DC power supply, a first resistor, a high-voltage guide post, a conductive spring, a first insulating support rod, a first metal support rod, a needle electrode and a first translation drive mechanism; the positive electrode of the first DC power supply is connected to one end of the first resistor through a wire, and the other end of the first resistor is connected to the high-voltage guide post through a wire, the high-voltage guide post is horizontally fixedly installed on the first insulating cover, one end of the high-voltage guide post is located outside the metal tank body, and the other end of the high-voltage guide post is located inside the metal tank body; the negative electrode of the first DC power supply is grounded through a wire; the first insulating support rod is coaxially fixed to the first metal support rod The invention relates to a combined support rod, which is horizontally sealed and passes through a first insulating cover. The combined support rod has axial freedom of movement relative to the first insulating cover. One end of the first metal support rod in the combined support rod always extends into the interior of the metal tank body. The needle electrode is vertically fixed to the end of the first metal support rod located inside the metal tank body. One end of the conductive spring sheet is fixed to the end of the high-voltage guide column located inside the metal tank body, and the other end of the conductive spring sheet overlaps and conducts with the first metal support rod. The first translation drive mechanism is located outside the metal tank body, and the first insulating support rod in the combined support rod is connected to the first translation drive mechanism.

5. The insulating material flashover test device for measuring the flashover voltage and the starting voltage according to claim 1, characterized in that: The charge measurement component includes an electrostatic probe, a second insulating support rod and a second translation drive mechanism; the second insulating support rod is horizontally sealed and passes through the second insulating cover, and the second insulating support rod has axial movement freedom relative to the second insulating cover; the electrostatic probe is vertically fixed on the end of the second insulating support rod located inside the metal tank body; the second translation drive mechanism is located outside the metal tank body, and the other end of the second insulating support rod is connected to the second translation drive mechanism.

6. The insulating material flashover test device for measuring the flashover voltage and the starting voltage according to claim 1, characterized in that: The surface flashover assembly includes a second DC power supply, a second resistor, an electrode plate, a second metal support rod, an insulating support plate, an insulating bracket, a first finger-shaped electrode, a second finger-shaped electrode, a lifting drive mechanism and a rotating drive mechanism; the positive electrode of the second DC power supply is connected to one end of the second resistor through a wire, and the other end of the second resistor is connected to the high-voltage guide rod at the center of the insulator cover through a wire; the second metal support rod vertically seals and passes through the bottom plate of the metal tank body, and the second metal support rod has axial freedom of movement relative to the bottom plate of the metal tank body; the electrode plate is horizontally fixed on the top of the second metal support rod, and the insulating sample piece is horizontally fixed on the upper surface of the electrode plate; the insulating support The support plate is horizontally arranged directly above the insulating sample piece, and the insulating support plate is fixedly connected to the bottom plate of the metal tank body through an insulating bracket; the first finger-shaped electrode and the second finger-shaped electrode are fixedly installed in parallel on the edge of the lower surface of the insulating support plate, the first finger-shaped electrode is connected to the high-voltage guide rod through a wire, the second finger-shaped electrode is connected to the metal tank body through a wire, and the second finger-shaped electrode is grounded through the metal tank body; the lifting drive mechanism and the rotary drive mechanism are located outside the metal tank body, the rotary drive mechanism is installed on the lifting drive mechanism, and the lower end of the second metal support rod is connected to the rotary drive mechanism; the electrode plate is grounded through the second metal support rod and the metal tank body in turn.

7. The insulating material flashover test device for measuring the flashover voltage and the starting voltage according to claim 6, characterized in that: The specimen support assembly comprises an insulating support plate, a metal support barrel, a metal floating support plate, a guide stud, a buffer support spring and a limit nut; the insulating support plate is horizontally arranged directly below the electrode plate, and the insulating support plate is fixedly connected to the insulating bracket; a circular opening is provided at the center of the insulating support plate, and the metal support barrel is fixedly installed in the circular opening at the center of the insulating support plate; the metal floating support plate is horizontally arranged inside the metal support barrel, and guide holes are uniformly opened along the circumference on the bottom plate of the metal support barrel, and the guide studs are arranged along the circumference. The metal support barrel is evenly fixed on the lower surface of the metal floating support plate, the guide stud extends through the guide hole to the bottom of the metal support barrel, and the limit nut is threadedly sleeved on the guide stud located under the bottom of the metal support barrel; the buffer support spring is sleeved on the guide stud between the metal floating support plate and the bottom of the metal support barrel; a through hole for the second metal support rod is opened in the center of the metal floating support plate and the center of the bottom of the metal support barrel; the metal support barrel is connected to the metal tank body through a wire, and the metal support barrel is grounded through the metal tank body.

8. The insulating material flashover test device for measuring the flashover voltage and the starting voltage according to claim 1, characterized in that: The flashover voltage and starting voltage measurement component includes a photomultiplier tube, an amplifier, an oscilloscope, a voltage divider and a voltage divider box; the photomultiplier tube is horizontally sealed and passes through a third insulating cover, the measuring end of the photomultiplier tube is located inside the metal tank body, and the signal output end of the photomultiplier tube is electrically connected to the oscilloscope through the amplifier; the voltage divider is arranged in parallel with the metal tank body, and the voltage divider is electrically connected to the oscilloscope through the voltage divider box.

9. An insulating material flashover test method, using the insulating material flashover test device for measuring flashover voltage and starting voltage according to claim 1, characterized in that: The steps include: Step 1: Open the observation window, and insert the insulating sample into the metal tank through the observation window until the insulating sample is placed on the flush upper surface of the electrode plate and the metal support barrel, and then close the observation window; Step 2: Fill the metal tank with insulating gas through the insulating gas injection port until the gas pressure reaches a set value, and then close the insulating gas injection port; Step 3: Start the first translation driving mechanism to drive the combined support rod composed of the first insulating support rod and the first metal support rod to move into the metal can body until the needle electrode is driven to move to the top of the center of the insulating sample piece; Step 4: starting the first DC power supply, applying a voltage between the needle electrode and the electrode plate, the voltage application time is 10 to 30 minutes, until the charge injection is completed on the surface of the insulating sample piece, and then turning off the first DC power supply; Step 5: Reversely start the first translation driving mechanism to drive the combined support rod composed of the first insulating support rod and the first metal support rod to move toward the outside of the metal can body until the needle electrode is driven to leave from above the insulating sample piece and move back to the initial position; Step 6: Start the second translation drive mechanism to drive the second insulating support rod to move into the metal tank until the electrostatic probe is driven to move to the top of the center of the insulating sample piece; Step 7: Start the second translation drive mechanism in reverse to drive the electrostatic probe to move from the center of the insulating sample piece to the location of the first inner circle measurement point, then start the rotary drive mechanism to drive the second metal support rod, the electrode plate and the insulating sample piece to rotate synchronously, and complete the charge measurement of the first inner circle measurement point through the electrostatic probe; Step 8: Repeat step 7, and complete the charge measurement of all measurement points from the inside to the outside in accordance with the charge measurement process of the first circle of measurement points on the inner side of the insulating sample piece; Step 9: After the charge measurement of the first circle of measurement points outside the insulating sample piece is completed, the second translation drive mechanism is started in the reverse direction to drive the second insulating support rod to move toward the outside of the metal tank until the electrostatic probe leaves the insulating sample piece and moves back to the initial position; Step 10: Start the lifting drive mechanism to drive the second metal support rod, the electrode plate and the insulating sample piece to rise synchronously until the insulating sample piece contacts the first finger-shaped electrode and the second finger-shaped electrode; at the same time, under the thrust of the buffer support spring, the metal floating support plate and the guide stud also rise synchronously until the limit nut abuts against the bottom plate of the metal support barrel; Step 11: Start the second DC power supply and apply voltage to the first finger-shaped electrode and the second finger-shaped electrode until a surface flashover phenomenon occurs; Step 12: Shield the observation window from light to prevent external light from entering the metal tank body, so that only flash light signals and corona light signals are visible inside the metal tank body; Step 13: Enable the photomultiplier tube, collect the flashover light signal and the corona light signal through the photomultiplier tube, then output the electrical signal from the photomultiplier tube, and further transmit it to the oscilloscope through the amplifier. At the same time, with the cooperation of the voltage divider and the voltage divider box, the flashover voltage and the starting voltage are displayed in real time on the oscilloscope; Step 14: Turn off the second DC power supply, start the lifting drive mechanism in reverse, drive the second metal support rod, the electrode plate and the insulating sample piece to descend synchronously, and the insulating sample piece is separated from the first finger-shaped electrode and the second finger-shaped electrode until the electrode plate contacts the metal floating support plate, the buffer support spring is compressed, the metal floating support plate and the guide stud descend synchronously, and the limit nut is separated from the barrel bottom plate of the metal support barrel, so that the electrode plate and the upper surface of the metal support barrel are restored to a flush state.

Images