Device for measuring surface potential and processing device and method thereof

Abstract

The invention belongs to the technical field of extra-high voltage equipment testing, and discloses a device for surface potential measurement and a processing device and method.The device comprises an electrostatic probe and a sealing cavity, the sealing cavity is provided with a port, and the port of the sealing cavity is provided with a sealing flange in a sealed mode; one end of the electrostatic probe is arranged in the sealing cavity, and all signal lines of the electrostatic probe penetrate through the sealing flange and extend out of the sealing cavity; the portions, penetrating through the sealing flange, of all the signal lines are connected with a sealing block in a sealed mode, a gap is formed between any two signal lines, and the space between any two signal lines is filled with materials of the sealing block. The sealing block is hermetically connected with the sealing flange; the sealing cavity or the sealing flange is provided with an inflation and deflation nozzle. According to the invention, under the condition that a probe signal line is not cut off, the static probe passes through the sealed cavity, and stable measurement of the surface potential of the insulation equipment in an SF6 environment is realized.

Description

Technical Field

[0001] The invention belongs to the technical field of ultra-high voltage equipment testing, and in particular relates to a device for measuring surface potential and a processing device and method thereof. Background Art

[0002] In order to simulate the surface charge accumulation of UHV equipment, such as GIL post insulators, pot insulators and bushing cores in an SF6 environment, it is usually necessary to put the scaled-down insulation equipment into a sealed experimental chamber, evacuate it, and then fill it with SF6 gas at a certain pressure to conduct voltage, temperature and other experiments. Most surface potential measurement experiments use Trek341B electrostatic probes, and the surface potential measurement of insulation equipment in an SF6 environment requires the electrostatic probe to pass through the sealed chamber.

[0003] The conventional method is to cut the electrostatic probe wire and reconnect the electrostatic probe through a metal flange with a terminal, with one end of the probe connected inside the sealed cavity and the plug end connected outside the sealed cavity. However, since the cut shielding layer of the electrostatic probe is damaged and the reconnected solder joint part changes the line impedance of the electrostatic probe, the original stability of the electrostatic probe is destroyed, and eventually the probe is damaged by discharge. Summary of the invention

[0004] In order to eliminate the influencing factors of probe damage caused by probe cutting from the root, the purpose of the present invention is to provide a device for surface potential measurement and its processing device and method. The present invention does not need to cut the electrostatic probe line (i.e., the signal line), thereby ensuring the stability of the electrostatic probe and realizing stable measurement of the surface potential of insulating equipment in an SF6 environment.

[0005] To achieve the above purpose, the technical solution adopted by the present invention is as follows: A device for measuring surface potential comprises an electrostatic probe and a sealed cavity, wherein the sealed cavity has a port, and the port of the sealed cavity is sealed with a sealing flange; One end of the electrostatic probe is arranged inside the sealed cavity, and all signal lines of the electrostatic probe pass through the sealing flange and extend to the outside of the sealed cavity; All signal lines pass through the sealing flange and are sealed and connected to a sealing block. There is a gap between any two signal lines, and the gap between any two signal lines is filled with the material of the sealing block. The sealing block is sealed and connected to the sealing flange; The sealing cavity or the sealing flange is provided with an air filling and discharging nozzle.

[0006] Preferably, the sealing flange comprises a flange and a flange end cover, the flange is sealed and connected to the port of the sealing cavity, a stepped hole is penetrated through the flange, the signal line penetrates the flange along the stepped hole, and the sealing block is sealed and arranged at the large diameter section of the stepped hole; The flange end cover is sealed and connected to the flange and presses the sealing block. The flange end cover is provided with a first wire through hole for the signal wire.

[0007] Preferably, a sealing groove is provided on the step surface and / or the surface of the large diameter section of the step hole on the flange, and a sealing ring for sealing the sealing block is provided in the sealing groove.

[0008] Preferably, the diameter of the first wire through hole on the flange end cover is smaller than the diameter of the sealing block, and a sealing groove is provided on the surface of the flange end cover at a position in contact with the flange and / or a position in contact with the sealing block, and a sealing ring is provided in the sealing groove.

[0009] Preferably, the flange is connected to the port of the sealing cavity by bolts, and the flange end cover is connected to the flange by bolts.

[0010] Preferably, the sealing block is made of epoxy resin block.

[0011] Preferably, the sealing block is cylindrical in shape.

[0012] The present invention also provides a method for processing the device for measuring surface potential as described above, comprising the following steps: The sealing block is processed on the signal line by casting, so as to realize the sealed connection between the signal line and the sealing block; and then the sealing block is sealed and connected with the sealing flange.

[0013] The present invention also provides a processing device for the device for measuring surface potential as described above, including a casting mold, the casting mold is cylindrical in shape, and the two ends of the casting mold are respectively provided with a split upper end cover and a split lower end cover, the split upper end cover and the split lower end cover are provided with a second line through hole for each signal line to pass through, and the split upper end cover and the split lower end cover are split along the diameter direction of the second line through hole.

[0014] Preferably, the casting mold comprises a circular wall support frame, in which a silicone mold is arranged, and the silicone mold contacts the inner surface of the circular wall support frame.

[0015] The present invention has the following beneficial effects: In the device for measuring surface potential of the present invention, the signal line is not subjected to any destructive treatment, and the structure of all signal lines is intact, especially the shielding layer inside is not damaged. Therefore, the present invention ensures the integrity of the signal line, thereby ensuring the stability of the electric probe, and realizing the stable measurement of the surface potential of the insulating equipment under the SF6 environment. The signal line is sealed with a sealing block, and the material of the sealing block is filled between any two signal lines, so that the sealed connection between the signal line and the sealing block is ensured; in addition, the sealing block is sealed with a sealing flange, so that the sealing performance of the signal line when passing through the sealing flange is ensured; the port seal of the sealing cavity is provided with a sealing flange, so that the sealing performance of the sealing cavity during the experiment is ensured, so that the overall sealing performance of the device for measuring surface potential of the present invention is ensured, and the experimental requirements are met. A gas filling and discharging nozzle is provided on the sealing cavity or the sealing flange, and the insulating gas (such as SF6 gas) can be filled into the sealing cavity by the gas filling and discharging nozzle, and the SF6 gas in the device can be discharged after the experiment. In summary, the present invention does not need to cut the signal line, ensures the stability of the electrostatic probe, and realizes the stable measurement of the surface potential of the insulating equipment under the SF6 environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the casting mold of the electrostatic probe line in an embodiment of the present invention.

[0017] Figure 2 It is a schematic diagram of the internal structure of the electrostatic probe wire casting mold in an embodiment of the present invention.

[0018] Figure 3 Schematic diagram of the sealing flange structure in an embodiment of the present invention.

[0019] Figure 4 2 is a cross-sectional view of a sealing flange in an embodiment of the present invention.

[0020] In the figure: 1. signal line; 2. casting mold; 3. split upper end cover; 4. silicone mold; 5. round wall support frame; 6. wire passing port; 7. split lower end cover; 8. flange end cover; 8-1. first wire passing through hole; 9. flange; 9-1. stepped hole; 10. flange end cover fixing through hole; 11. flange fixing through hole; 12. inner sealing groove of flange end cover; 13. outer sealing groove of flange end cover; 14. flange threaded hole; 15. flange bottom sealing groove; 16. flange upper side wall sealing groove; 17. flange lower side wall sealing groove; 18. sealing block; 19. second wire passing through hole. DETAILED DESCRIPTION

[0021] According to the technical solution of the present invention, without changing the essential spirit of the present invention, a person skilled in the art can propose a variety of interchangeable structures and implementations. Therefore, the following specific implementation methods and drawings are only examples of the technical solution of the present invention and should not be regarded as the entirety of the present invention or the limitation of its technical solution.

[0022] Example In this embodiment, the signal line 1 of the electrostatic probe is placed in a casting mold 2, the part is cured into an epoxy resin block by curing epoxy at room temperature, and the epoxy resin block is fixed on the sealed cavity by a specially designed sealing flange.

[0023] First, the room temperature curing part of this embodiment is introduced: The electrostatic probe wire casting mold of this embodiment adopts a cylindrical silicone mold 4 with a bottom at one end, and is fixed and supported by a 3D printed split upper end cover 3, a round wall support frame 5 and a split lower end cover 7. A square wire port 6 is cut in the center of the bottom of the silicone mold 4, so that all signal wires 1 of the electrostatic probe pass through the wire port 6.

[0024] In order to ensure the insulation margin between the four signal wires of the electrostatic probe, the four signal wires 1 are separated by a certain distance through the split upper end cover 3 of the casting mold 2 and the separated spliced ​​fixed partitions of the split lower end cover 7 .

[0025] When pouring begins, first fix and seal the signal line 1 and the pouring mold 2, and fix the split lower end cover 7 and the round wall support frame 5 with insulating tape. To prevent the epoxy resin AB glue from leaking, use 704 silicone rubber to bond the wire port 6 of the pouring mold 2 to the signal line 1 to play a sealing role.

[0026] After the 704 silicone rubber solidifies, you can start pouring epoxy resin AB glue at room temperature.

[0027] The pouring scheme of this embodiment adopts room temperature curing epoxy resin AB glue, by mixing component A and component B in a beaker according to a mass ratio of 3: 1, and stirring evenly. After stirring evenly, the beaker is placed in an oven and vacuumed at room temperature. Pump and release gas three times to eliminate the bubbles in the epoxy resin AB glue, and then pour. The epoxy resin AB glue with bubbles eliminated is slowly injected along the wall of the silicone mold 4, and the epoxy resin AB glue liquid level is stopped when the mold specified scale line is reached. After the pouring is completed, the casting mold 2 is placed in the oven for vacuuming. Repeat the pumping and release operation three times to eliminate most of the bubbles in the mold, and maintain it for 30 minutes under a vacuum environment of 30Pa to eliminate small bubbles in the epoxy resin AB glue as much as possible. After the vacuuming is completed, the casting mold 2 is taken out and placed at room temperature for two days of curing. During this period, it is necessary to maintain the position of the casting mold 2 to keep it horizontal to prevent the epoxy resin AB glue liquid level from tilting, causing the cured epoxy resin block to be unable to be tightly combined with the sealing ring, causing air leakage.

[0028] The sealing flange structure of this embodiment: The sealing flange includes flange 9 and flange end cover 8. The flange 9 part adopts the method of combining the epoxy resin block with the groove and the flange end cover 8 to fix the poured epoxy resin block. The flange 9 sealing structure adopts the method of combining face sealing and shaft sealing. The first face seal is the flange bottom sealing groove 15 and the sealing ring arranged inside it. The second face seal is the flange end cover inner sealing groove 12, the flange end cover outer sealing groove 13 and the sealing ring arranged inside them. Two large and small "O" type sealing rings are respectively in contact with the flange end cover 8 and the upper end face of the epoxy resin block for sealing. The two shaft seals are the flange upper side wall sealing groove 16, the flange lower side wall sealing groove 17 and the sealing ring arranged inside them. The selection size of the sealing ring and the design of the sealing groove size are both referred to the 5th edition of "SF6 High Voltage Electrical Appliance Design". Specifically, the flange 9 is sealed and connected to the port of the sealing cavity, and bolts are used to detachably connect the flange 9 to the sealing cavity. A stepped hole 9-1 is penetrated on the flange 9, and the signal line 1 penetrates the flange 9 along the stepped hole 9-1. The epoxy resin block is sealed and arranged at the large diameter section of the stepped hole 9-1 through a sealing groove and a sealing ring; the flange end cover 8 is sealed and connected to the flange 9 and presses the sealing block 18, and the flange end cover 8 is provided with a first wire through hole 8-1 for the signal line 1. The diameter of the first wire through hole 8-1 on the flange end cover 8 is smaller than the diameter of the sealing block 18, and a sealing groove is provided on the surface of the flange end cover 8 at a position in contact with the flange 9 and / or a position in contact with the sealing block 18, and a sealing ring is provided in the sealing groove. The sealing block 18 and the flange 9 are sealed by a sealing groove and a sealing ring, and the flange 9 and the sealing cavity are sealed by a sealing groove and a sealing ring.

[0029] To prevent dust from affecting the sealing effect, before sealing, use alcohol and non-woven fabric to wipe and clean each sealing groove, the end face of flange 9 and the "O" type sealing ring to remove the dust on the surface, and then put the "O" type sealing ring into the sealing groove. After the epoxy resin block is placed in the groove of flange 9, the flange end cover 8 is fastened to the flange threaded hole 14 with bolts, so as to fix and press the epoxy resin block tightly to prevent the epoxy resin block from being squeezed out under the action of the positive pressure gas in the sealing cavity. After pressing, the "O" type sealing ring is within the normal elastic deformation range, and fits tightly with the end face of the epoxy resin block, the end face of the flange end cover 8 and the end face of the flange 9, forming a good sealing effect.

[0030] The curing scheme of this embodiment: through the 3D printed split upper end cover 3, split lower end cover 7 and round wall support frame 5, it is supported and fixed on the outside of the silicone mold 4, realizing the concept of pouring epoxy resin blocks in the middle of each signal line 1 under room temperature. The non-adhesiveness of the silicone mold 4 and the cured epoxy resin AB glue makes it easy to separate the cured epoxy resin block. Among them, the split upper end cover 3 and the split lower end cover 7 are provided with a second wire through hole 19 for each signal line 1 to pass through, and the split upper end cover 3 and the split lower end cover 7 are split along the diameter direction of the second wire through hole 19, so as to ensure the assembly between the split upper end cover 3, the split lower end cover 7 and the signal line 1. At the same time, the second wire through hole 19 and the signal line can be clearance-fitted or over-fitted to prevent leakage when pouring epoxy resin.

[0031] The flange 9 adopts a combination of face sealing and shaft sealing, and cooperates with the flange end cover 8 to fix the epoxy resin block and achieve a sealing effect.

[0032] When the device for measuring surface potential of the present invention is used, one end of the electrostatic probe is arranged inside the sealed cavity, and all signal lines 1 of the electrostatic probe pass through the sealing flange and extend to the outside of the sealed cavity; all signal lines 1 and the sealing flange are sealed by a sealing structure (such as a sealing ring and a sealing groove) and a sealing block (such as an epoxy resin block). At the same time, a gas filling and discharging nozzle is arranged on the sealed cavity or the sealing flange to facilitate the filling and discharging of the insulating gas.

[0033] In the prior art, the electrostatic probe is cut through the sealed cavity. Since the original shielding layer of the signal line 1 is destroyed and the original line impedance of the signal line is changed, the electrostatic probe is easily interfered by external signals, thereby causing discharge damage to the measuring probe. The solution of the present invention is to achieve the measurement of the surface potential of an object under a specific gas atmosphere and a specific pressure by coordinating the signal line 1 through the sealed cavity without cutting the signal line of the probe through room temperature curing and sealing flange.

[0034] In summary, the present invention adopts an epoxy casting method to cast the three signal wires and one ground wire of the electrostatic probe in epoxy resin, and cooperates with the designed flange to enable the electrostatic probe to pass through the sealed cavity without cutting the probe, thereby achieving stable measurement of the surface potential of the insulating equipment in the SF6 environment.

[0035] The above content is a further detailed description of the present invention in combination with a specific preferred embodiment. It cannot be determined that the specific embodiments of the present invention are limited to this. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as belonging to the present invention. The scope of patent protection shall be determined by the submitted claims.

[0036] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A device for measuring surface potential, characterized in that It includes an electrostatic probe and a sealed cavity, wherein the sealed cavity has a port, and the port of the sealed cavity is sealed with a sealing flange; One end of the electrostatic probe is arranged inside the sealed cavity, and all signal lines (1) of the electrostatic probe pass through the sealing flange and extend to the outside of the sealed cavity; The portion where all signal lines (1) pass through the sealing flange is sealed and connected to a sealing block (18), there is a gap between any two signal lines (1), and the space between any two signal lines (1) is filled with the material of the sealing block (18); The sealing block (18) is sealingly connected to the sealing flange; The sealing cavity or the sealing flange is provided with an air filling and discharging nozzle.

2. The device for measuring surface potential according to claim 1, characterized in that: The sealing flange comprises a flange (9) and a flange end cover (8); the flange (9) is sealingly connected to a port of the sealing cavity; a stepped hole (9-1) is provided through the flange (9); the signal line (1) passes through the flange (9) along the stepped hole (9-1); and a sealing block (18) is sealingly arranged at a large diameter section of the stepped hole (9-1); The flange end cover (8) is sealedly connected to the flange (9) and presses the sealing block (18). The flange end cover (8) is provided with a first wire through hole (8-1) for the signal wire (1).

3. The device for measuring surface potential according to claim 2, characterized in that: A sealing groove is provided on the flange (9) on the step surface and / or the surface of the large diameter section of the step hole (9-1), and a sealing ring for sealing the sealing block (18) is provided in the sealing groove.

4. The device for measuring surface potential according to claim 2, characterized in that: The diameter of the first wire-passing through hole (8-1) on the flange end cover (8) is smaller than the diameter of the sealing block (18), and a sealing groove is provided on the surface of the flange end cover (8) at a position in contact with the flange (9) and / or a position in contact with the sealing block (18), and a sealing ring is provided in the sealing groove.

5. The device for measuring surface potential according to claim 2, characterized in that: The flange (9) is connected to the port of the sealing chamber by bolts, and the flange end cover (8) is connected to the flange (9) by bolts.

6. The device for measuring surface potential according to claim 1, characterized in that: The sealing block (18) is made of epoxy resin block.

7. The device for measuring surface potential according to claim 1, characterized in that: The sealing block (18) is cylindrical in shape.

8. The method for processing the device for measuring surface potential according to any one of claims 1 to 7, characterized in that: The process includes the following: A sealing block (18) is processed on the signal line (1) by casting, thereby achieving a sealed connection between the signal line (1) and the sealing block (18); and then the sealing block (18) is sealed and connected to the sealing flange.

9. The processing device for the device for measuring surface potential according to any one of claims 1 to 7, characterized in that: The invention comprises a casting mold (2), the casting mold (2) is cylindrical in shape, and two ends of the casting mold (2) are respectively provided with a split upper end cover (3) and a split lower end cover (7), the split upper end cover (3) and the split lower end cover (7) are provided with a second wire through hole (19) for each signal wire (1) to pass through, and the split upper end cover (3) and the split lower end cover (7) are split along the diameter direction of the second wire through hole (19).

10. The processing device for the device for measuring surface potential according to claim 9, characterized in that: The casting mold (2) comprises a round wall support frame (5), a silicone mold (4) is arranged in the round wall support frame (5), and the silicone mold (4) is in contact with the inner surface of the round wall support frame (5).

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