A plasma reactor, device and method for improving the performance of cable sheath surface aging area

Abstract

The present invention provides a plasma reactor, device and method for improving the performance of the aging area on the surface of a cable sheath. One end of the plasma reactor joint is connected to a pipeline, and the other end is connected to a reactor body. The reactor body includes an extension part and a reaction part. The length direction of the extension part is set at an angle with the horizontal plane. The cable sheath to be treated is placed horizontally below the reaction part. The cable sheath to be treated is a ground electrode below the cable sheath to be treated. The reaction part includes a convex block and a bottom surface. A reactor treatment area is formed between the bottom surface and the cable sheath to be treated. A groove is provided in the convex block. A pressing block is provided in the groove. A high-voltage electrode is placed in the groove. The present invention determines the size of each structural parameter of the reactor to achieve the best discharge effect, determines the medium ratio and the parameters related to the power supply, can quickly and accurately improve the treatment effect of plasma on the material surface, reduce the experimental error caused by human operation, and has important significance for improving the plasma modification effect.

Description

Technical Field

[0001] The present invention relates to the technical field of insulators, and in particular to a plasma reactor, a device and a method for improving the performance of an aging area on the surface of a cable sheath. Background Art

[0002] With the development of power systems, the demand for high-performance insulation materials in related fields is becoming increasingly urgent. Polymer insulation is an important insulation structure of power systems, such as polyethylene, epoxy resin, etc.

[0003] As the insulation material of the cable outer sheath, polyethylene has excellent insulation performance, heat resistance, chemical resistance, mechanical strength and other characteristics, and plays an important role in the safe and reliable transmission of electrical energy or signals by the cable. After long-term use, the outer sheath is inevitably facing the risk of material aging and functional failure due to the breakage and oxidation of the molecular chain. The formation and expansion of aging areas are one of the most typical aging phenomena. Polyethylene is exposed to a variety of environments for a long time, such as extreme weather, ultraviolet radiation and environmental erosion, which deteriorates the material performance and destroys chemical bonds at the molecular level. Under the action of tensile force, the mechanical properties of polyethylene decrease with the increase of operating time, and the surface of the material ages, which greatly reduces the mechanical strength of the material. At the same time, due to the weakening of comprehensive performance, local discharge may occur around the aging area, and eventually form a flashover, leading to accidents.

[0004] In response to the aging of the cable outer sheath surface, surface coating technology is currently often used to maintain the aging cables. However, this physical coating method may face the problem of large-area interference. At the same time, because a new macro interface is introduced between the coating layer and the original surface of the insulator, a new interface polarization may be formed, causing space charge accumulation, leading to electric field distortion, and exposing the insulation to the potential risk of failure again. In actual sites, heat shrink tubing or hot welding methods are often used for physical covering, but the defects cannot be completely treated from a microscopic perspective. The defects still exist, which greatly reduces the reliability of cable insulation. Therefore, a new method for handling from a microscopic perspective is urgently needed to reduce the possibility of recurrence of cable outer sheath accidents after treatment.

[0005] Patent application number CN202311000445.5 discloses a cable repair device, which cuts off the sheath of the damaged cable, crushes it, melts it and mixes it with repair glue to form a repair material for the cable skin, and then injects the melted and mixed material into a cavity composed of the equipment to complete the repair of the cable skin. Although raw materials are utilized and the required materials and costs are reduced, the air gap generated during filling cannot be avoided due to on-site processing.

[0006] The invention patent with application number CN201120391132.3 discloses a cable sheath repair device, which heats the electrically heated constant temperature die seat to melt the repair tape of the same material as the sheath wrapped around the cable in the die and fuse it with the cable sheath; the molten plastic is made more compact by adjusting the compression bolts to apply pressure and eliminate the bubbles in it. However, the device itself is heavy and cannot be used for high-altitude cable repair operations.

[0007] The invention patent with application number CN202210225157.9 discloses a cable sheath repair system and method in a drainage pipe, which uses an overhead device in the cable sheath repair system in a drainage pipe to suspend the cable in the drainage pipe. Insulating sealant is poured into the drainage pipe. The outer sheath of the cable can be repaired conveniently and effectively, but it still cannot eliminate the existence of defects such as aging at the microscopic level.

[0008] The invention patent with application number CN202310400188.8 discloses a device and method for improving the insulation surface performance of cable accessories based on styrene / atmospheric pressure plasma. The reactor used is a jet reactor, and most plasma research on cable treatment uses a jet structure, but the treatment area is small and the controllability is relatively poor. The jet has high requirements for distance and the accuracy needs to reach the millimeter level. The distance between the plasma generation area and the sample directly affects the quality of the treatment effect.

[0009] Therefore, some existing technologies use physical coating to eliminate the defects of the polyethylene outer sheath on a macro scale, but aging defects still exist at the micro level, and problems such as charge accumulation will still exist. The operation is difficult and has great limitations by melting the improved material and filling it into the original cable under pressure. The mechanical stress generated by the use of the pressurizing device can easily accelerate the insulation aging of the stressed part of the cable, resulting in poor treatment effect. Plasma uses jet treatment for the interface compatibility of the insulation of cable accessories, and there is no plasma reactor for aging treatment. In summary, the existing technology is relatively lacking in research on cable sheath treatment, and related technologies still need to be improved. Summary of the invention

[0010] Purpose of the invention: In view of the problems existing in the above-mentioned prior art, the present invention constructs a plasma reactor for improving the performance of the aging area on the surface of the cable sheath. The present invention also proposes a device and method for improving the performance of the aging area on the surface of the cable sheath.

[0011] Technical solution: In one aspect of the present invention, a plasma reactor for improving the performance of an aging area on the surface of a cable sheath is provided. The plasma reactor comprises a joint, one end of which is connected to a pipe, and the other end of which is connected to a reactor body. The reactor body comprises an extension portion and a reaction portion. The length direction of the extension portion forms an angle α with a horizontal plane. The cable sheath to be treated is placed horizontally below the reaction portion. A ground electrode is provided below the cable sheath to be treated, and the reaction portion comprises a protrusion and a bottom surface. A reactor treatment area is formed between the bottom surface and the cable sheath to be treated. The protrusion is arranged at the end of the extension portion upward along the bottom surface and is parallel to the length direction of the extension portion. A groove is provided inside the protrusion, a pressing block is provided in the groove, and a high-voltage electrode is placed in the groove and fixed by the pressing block.

[0012] Further, including:

[0013] The bottom surface includes end A, which is an end away from the extension part and parallel to the width direction of the extension part. A boss is arranged between end A and the cable sheath to be processed. The boss is in close contact with the cable sheath to be processed. The boss makes the reactor processing area form a certain height distance with the surface of the cable sheath to be processed, and the height of the boss is 2 to 3 mm.

[0014] Further, including:

[0015] The included angle α between the length direction of the extension part of the plasma reactor and the horizontal plane is 15-25°, that is, the high-voltage electrode and the ground electrode form an included angle of 15-25°.

[0016] The height of the boss is 2.82 mm, so that the extended portion of the plasma reactor forms an angle of 20° with the surface of the cable sheath to be processed, and the high-voltage electrode and the ground electrode also form an angle of 20°.

[0017] Further, including:

[0018] A through hole is provided on the convex block close to the extension portion, and the through hole is connected with the surrounding groove to form a connection channel between the high-voltage electrode and the high-voltage line.

[0019] Further, including:

[0020] The shortest distance between the high-voltage electrode and the cable sheath to be processed is controlled to be 3-5 mm.

[0021] On the other hand, the present invention also provides a device for improving the performance of the aging area on the surface of a cable sheath, the device comprising an argon gas bottle, a first flowmeter, a second flowmeter, an anti-backflow bottle, a medium bottle and the above-mentioned plasma reactor, wherein the output gas of the argon gas bottle is divided into two, the first gas path passes through the first flowmeter to enter the anti-backflow bottle, and then is connected to the medium bottle, the second gas path passes through the second flowmeter and is directly connected to the medium bottle, and the medium is brought out by the bubbling method and then merged with the first gas path and passed into the plasma reactor. When ready, the pulse source is turned on and the discharge is observed to ensure that the surface of the cable sheath to be treated can fully contact the reactor treatment area of ​​the plasma reactor to ensure the uniformity of the formed thin film.

[0022] Finally, the present invention also provides a method for improving the performance of the aging area on the surface of a cable sheath, the method using the above-mentioned device, specifically comprising the following steps:

[0023] Step S1: clean the protective cover of the cable to be processed and make it fit the protective cover of the cable to be processed completely with the plasma reactor;

[0024] Step S2: Open the argon gas bottle, adjust the flow rate of the first flowmeter, and allow the argon gas to flow directly into the plasma reactor. During the waiting period, confirm whether the wind speed of the corresponding reaction part is stable and whether there is any blockage. If both are in good condition, turn on and adjust the relevant parameters of the pulse source to send data, and observe whether the discharge is normal. If stable, turn off the power supply and close the second flowmeter.

[0025] Step S3: adjust the flow rate of the second flow meter so that argon gas is passed into the anti-backflow bottle and the medium bottle in sequence, and bubbles are generated in the medium bottle. Observe whether the bubble generation is stable. If the bubble generation is stable, wait until the medium completely removes all the original air in the gas path, and then slowly adjust the first flow meter to the corresponding flow rate. During the adjustment, always pay attention to the liquid level in the catheter of the anti-backflow bottle and the medium bottle to avoid backflow.

[0026] Step S4: After adjusting the flow rate of argon gas and the flow rate of the medium, if the bubbles are still in a stable state, turn on and adjust the relevant parameters of the pulse source and send data to observe whether the discharge is normal at this time, and ensure that the surface of the cable sheath can fully contact the reactor processing area of ​​the plasma reactor to ensure the uniformity of the formed film;

[0027] Step S5: According to steps S1-S4, the reaction is continued for several minutes, and the relevant parameters of the pulse source and the flow rate ratio of argon gas to the medium are continuously optimized until the optimal modification of the insulation surface of the cable protective sheath to be treated is achieved.

[0028] Further, including:

[0029] The relevant parameters of the pulse source after optimization are: voltage amplitude is 17~20kV, adjustment frequency is 6~8kHz, rising edge and falling edge are both 100~200ns; the optimized argon and medium flow rate ratio is: 1~2L / min argon and 15~25ml / min medium.

[0030] Further, including:

[0031] The medium in the medium bottle is n-hexane.

[0032] Beneficial effects: Compared with the prior art, the present invention has the following advantages:

[0033] (1) The present invention makes a revolutionary improvement on the structure of the plasma reactor in the prior art, adopts a plate-type dielectric barrier discharge to ensure the uniformity of the formed thin film, thereby greatly improving the reliability of the optimized cable. Specifically: the processing area setting size of the reactor of the present invention can be suitable for most aging area treatments; the design of the bosses on both sides of the reactor ensures that the reactor processing area is at a certain distance from the sample surface, avoiding damage to the surface film due to the reactor scratching during dynamic treatment; the reactor of the present invention is provided with a 5-8 mm through hole gap on one side of the confining groove near the tail end. This design not only facilitates the connection between the high-voltage electrode and the high-voltage line, but also ensures that the plasma directly acts on the surface of the material to be treated, while providing sufficient energy to fragment and deposit hydrocarbon media such as n-hexane.

[0034] (2) The medium of the present invention uses n-hexane, which is a pure carbon chain, which can ensure that the cable sheath insulation surface is modified and no impurity elements are introduced. In order to improve the hydrophobicity, more methyl groups need to be introduced. n-hexane can obtain a large number of methyl groups by simply breaking. Therefore, the effect obtained is to improve the water contact angle and better repair surface cracks. As a drug itself, n-hexane is less toxic and less harmful.

[0035] (3) The present invention determines the dimensions of various structural parameters of the reactor to achieve the best discharge effect, determines the medium ratio and power supply related parameters, can quickly and accurately improve the plasma treatment effect on the material surface, and reduce the experimental errors caused by human operation, which is of great significance to improving the plasma modification effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 is a schematic diagram of the three-dimensional structure of the plasma reactor described in Example 1 of the present invention;

[0037] Figure 2 yes Figure 1 The main view of

[0038] Figure 3 yes Figure 1 A top view of

[0039] Figure 4 It is a schematic diagram of the structure of the device for improving the performance of the aging area on the surface of the cable sheath according to Embodiment 2 of the present invention;

[0040] Figure 5 is a flow chart of a method for improving the performance of an aging area on a cable sheath surface according to Embodiment 2 of the present invention;

[0041] Figure 6 Schematic diagrams comparing the surface microscopic morphology of the cable sheath before and after the treatment of the cable sheath according to Example 2 of the present invention, wherein (a) is a schematic diagram of the microscopic morphology of the cable sheath before treatment, (b) is a schematic diagram of the microscopic morphology after treatment using the improvement method of the present invention, and (c) is a schematic diagram of the microscopic morphology after treatment using a traditional jet reactor;

[0042] Figure 7 Schematic diagram comparing the surface water contact angles of the cable sheath before and after the treatment of the cable sheath according to Example 2 of the present invention; wherein (a) is a schematic diagram of the surface water contact angle of the cable sheath before treatment, (b) is a schematic diagram of the surface water contact angle after treatment using the improvement method of the present invention, and (c) is a schematic diagram of the surface water contact angle after treatment using a traditional jet reactor;

[0043] In the figure, 1-argon gas bottle; 21-first flow meter; 22-second flow meter; 3-anti-backflow bottle; 4-medium bottle; 5-plasma reactor; 51-connector; 52-reaction part; 521-bump; 5211-through hole; 522-bottom surface; 5221-end A; groove-523; 53-extension part; 54-boss; 6-pressing block; 7-cable sheath to be processed. DETAILED DESCRIPTION

[0044] In order to better understand the present invention, the technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0045] Example 1

[0046] The present invention first provides a plasma reactor for improving the performance of the cable sheath surface aging area, such as Figure 1 As shown, it uses plasma spraying modification technology to simply and quickly improve the performance of cable sheaths, improve the electrical performance of cable systems, extend the service life of existing power transmission and distribution cables, and improve various performances. At the same time, the present invention can be extended to other industrial application materials for power system insulation. The plasma reactor 5 uses Rigid4000 resin, with a total length of 116mm, a width of 16mm, and a height of 20mm. It includes a connector 51, one end of which is connected to the pipeline and the other end is connected to the reactor body. The connector 51 is a cylindrical connector with a length of 14mm, an outer diameter of 8mm, and an inner diameter of 4mm.

[0047] Behind the joint 51 is the reactor body, which is connected to the joint 51 and is 102 mm long, 16 mm wide and 20 mm high. It includes an extension part 53 and a reaction part 52. The length direction of the extension part 53 is set at an angle α with the horizontal plane, and the range of the angle α is 15 to 25°. The cable sheath 7 to be treated is placed horizontally below the reaction part 52. The ground electrode is below the cable sheath 7 to be treated, and the reaction part 52 includes a protrusion 521 and a bottom surface 522. A reactor processing area is formed between the bottom surface 522 and the cable sheath 7 to be treated. The protrusion 521 is arranged at the end of the extension part 53 along the bottom surface and is parallel to the length direction of the extension part 53. A groove 523 is opened inside the protrusion 521, and a pressing block 6 is arranged in the groove 523. The high-voltage electrode is placed in the groove 523 and fixed with the pressing block 6. In this embodiment, the outer rectangle of the rectangular groove 523 is 24 mm long and 16 mm wide, and the inner rectangle is 18 mm long, 10 mm wide, and 8 to 10 mm high, which is high enough to prevent the high-voltage electrode from creeping toward the ground electrode; the pressure block in the groove 523 is 17 mm long, 9 mm wide, and 9 mm high, which is used to prevent the high-voltage electrode from sliding.

[0048] Further, such as Figure 2 As shown, the bottom surface 522 in this embodiment includes an end A5221, which is an end away from the extension portion 53 and parallel to the width direction of the extension portion 53. A boss 54 is provided between the end A5221 and the cable sheath 7 to be processed, and the boss 54 is in close contact with the cable sheath 7 to be processed. The boss 54 forms a certain height distance between the reactor processing area and the surface of the cable sheath 7 to be processed, and the height of the boss 54 is 2 to 3 mm. In this embodiment, the reactor processing area width is set to 12 to 14 mm, which can be applied to most aging area processing.

[0049] Specifically, a 2-3 mm boss is provided at the tail end in contact with the cable sheath, so that the high-voltage electrode and the ground electrode form an angle of 15-25°, and the surface to be treated is close to the bottom surface of the boss. During the treatment process, it is only necessary to ensure that the surface to be treated is in close contact with the bottom surface of the reactor boss to ensure that the modification effect is close to the theoretical effect, and the shortest contact distance between the high-voltage electrode and the surface of the cable sheath to be treated is controlled at about 3-5 mm, and the angle between the electrodes is combined with fluid mechanics to achieve a better treatment effect.

[0050] In this embodiment, the height of the boss 54 is 2.82 mm, so that the extension portion 53 of the plasma reactor forms an angle of 20° with the surface of the cable sheath 7 to be treated, and the high voltage electrode and the ground electrode also form an angle of 20°, which can achieve the best treatment effect.

[0051] The design of the bosses 54 on both sides of the present invention ensures that the reactor processing area is at a certain distance from the sample surface, avoiding damage to the surface film due to the reactor scratching during dynamic processing. In addition, during the processing process, the surface of the cable sheath to be processed is in close contact with the bottom surface of the boss to ensure that the spacing between different processed samples is fixed, reducing errors.

[0052] In this embodiment, if Figure 3 As described above, a through hole 5211 is provided on the protrusion 521 near the extension 53, and the through hole 5211 is connected with the groove 523. The width d of the through hole on the side of the groove near the tail end is 5 to 8 mm, which is used to connect the high-voltage electrode with the high-voltage wire, avoiding the contact between the high-voltage wire and the high-voltage electrode. If the high-voltage wire is tilted for a long time, it will cause poor contact between the high-voltage wire and the high-voltage electrode. If the contact is poor, it will lead to insufficient energy, that is, the design of the through hole 5211 ensures that the plasma directly acts on the surface of the material to be processed, and at the same time provides sufficient energy to fragment and deposit hydrocarbon media such as n-hexane, so as to solve the problem of hydrophilic modification on the surface of the insulating material caused by incomplete activation of the plasma-driven hydrocarbon media modification reaction medium such as n-hexane.

[0053] Therefore, the plasma reactor structure for cable sheath treatment provided by the present invention greatly improves the reliability of the cable and reduces the effect error caused by manual operation.

[0054] Example 2

[0055] The present invention also provides a device for improving the performance of the aging area on the surface of the cable sheath, such as Figure 4 As shown, the device includes an argon gas bottle 1, a first flow meter 21, a second flow meter 22, an anti-backflow bottle 3, a medium bottle 4 and the plasma reactor 5 in Example 1. The output gas of the argon gas bottle 1 is divided into two. The first gas path passes through the first flow meter 21 to enter the anti-backflow bottle 3, and then is connected to the medium bottle 4. The second gas path passes through the second flow meter 22 and is directly connected to the medium bottle 4. The medium is taken out by the bubbling method and then merged with the first gas path and passed into the plasma reactor 5. After preparation, the pulse source is turned on and the discharge is observed to ensure that the surface 7 of the cable sheath to be treated can fully contact the reactor treatment area of ​​the plasma reactor 5 to ensure the uniformity of the formed film.

[0056] Example 3

[0057] The present invention also provides a method for improving the performance of the cable sheath surface aging area, such as Figure 5 As shown, the method uses the device described in Example 2, and specifically includes the following steps:

[0058] Step S1: clean the protective cover 7 of the cable to be processed and make it fit the plasma reactor 5 completely;

[0059] Specifically: Place the cable sheath surface 7 horizontally upward, spray the cable sheath surface 7 with 95% industrial alcohol twice, and wipe it repeatedly with dust-free paper for three to five times to ensure that there is no stain left on the surface of the accessory. After wiping it clean, let it stand for sixty seconds, and after the remaining alcohol evaporates completely, it will be completely attached to the plasma reactor 5.

[0060] Step S2: open the argon gas bottle 1, adjust the flow of the first flowmeter 21, and allow the argon gas to directly flow into the plasma reactor 5. During the waiting period, confirm whether the wind speed of the corresponding reaction part 52 is stable and whether there is any blockage. If both are in good condition, turn on and adjust the relevant parameters of the pulse source to send data, and observe whether the discharge is normal. If it is stable, turn off the power supply and close the second flowmeter 22.

[0061] Specifically: open the argon gas bottle 1, slowly adjust the first flowmeter 21 to 1-2L / min, so that the purity of 99.999% Ar is directly introduced into the plasma reactor 5, wait for 30 seconds, during which you can use the back of your hand to feel whether the wind speed of the reaction part 52 of the plasma reactor 5 is stable and whether there is any blockage. If everything is in good condition, turn on the pulse source to adjust the voltage amplitude to 17-20kV, adjust the frequency to 6-8kHz, and the rising and falling edges to 100-200ns, send data, and observe whether the discharge is normal. If it is stable, turn off the power supply, adjust the first flowmeter 21 to 0L / min, and proceed to the next step.

[0062] Step S3 adjusts the flow rate of the second flowmeter 22 so that argon gas is passed into the anti-backflow bottle 3 and the medium bottle 4 in turn, bubbles are generated in the medium bottle 4, and whether the bubble generation is stable is observed; if the bubble generation is stable, wait until the medium has completely eliminated all the original air in the gas path, and then slowly adjust the first flowmeter 21 to the corresponding flow rate. During the adjustment, always pay attention to the liquid level in the catheter of the anti-backflow bottle 3 and the medium bottle 4 to avoid backflow.

[0063] Specifically: First, adjust the second flowmeter 22 to 15-25 ml / min, so that the inert gas Ar with a purity of 99.999% is passed into the anti-backflow bottle 3 and the hydrocarbon medium bottle 4 such as n-hexane in turn, and bubbles are generated in the hydrocarbon medium bottle 4 such as n-hexane, and observe whether the bubble generation is stable. If the bubble generation is stable, wait for 3-4 minutes until the medium completely removes the original air in the gas path, and then slowly adjust the first flowmeter 21 to 1-2 L / min. During the adjustment, always pay attention to the liquid level in the anti-backflow bottle and the catheter in the medium bottle to avoid backflow.

[0064] After adjusting the flow rate of argon gas and the flow rate of the medium in step S4, if the bubbles are still in a stable state, turn on and adjust the relevant parameters of the pulse source and send data to observe whether the discharge is normal at this time, and ensure that the cable sheath surface 7 can fully contact the reactor processing area of ​​the plasma reactor 5 to ensure the uniformity of the formed film.

[0065] Specifically: after adjusting the flow rate of hydrocarbon media such as argon gas to 1-2L / min and n-hexane to 15-25ml / min, if the bubbles are in a stable state, turn on the pulse source to adjust the voltage amplitude to 17-20kV, the frequency to 6-8kHz, the rising and falling edges to 100-200ns, send data, and observe whether the discharge is normal. Ensure that the surface 7 of the cable sheath to be treated can fully contact the reaction area of ​​the reaction part 52 of the plasma reactor 5 to ensure the uniformity of the formed film, thereby greatly improving the reliability of the optimized cable.

[0066] Step S5 continues the reaction for several minutes, and continuously optimizes the relevant parameters of the pulse source and the flow rate ratio of argon gas to the medium until the best modification of the insulating surface of the cable protective sheath 7 to be treated is achieved.

[0067] In this embodiment, polyethylene for cable outer sheath is used as the treatment material. The material is treated for 5 minutes under the above-mentioned experimental device and treatment conditions. After optimization, it is found that when the pulse source adjusts the voltage amplitude to 17-20 kV, the frequency to 6-8 kHz, the rising and falling edges are both 100-200 ns, and the flow rate ratio of 1-2 L / min argon and 15-25 ml / min n-hexane and other hydrocarbon media is used, better modification of the polyethylene insulation surface can be achieved.

[0068] In this embodiment, the optimal parameter configuration is: the optimal medium ratio is that the main gas path Ar flow rate is 1L / min and the n-hexane medium flow rate is 15mL / min; the optimal source parameters are the voltage amplitude of 17kV, the frequency of 7kHz, and the rising and falling edges are both 100ns.

[0069] The comparison results of the surface microstructure of the material before and after plasma treatment are as follows: Figure 6 As shown, under high magnification, we can see Figure 6 (a) shows that the untreated insulation surface has aging defects such as cracks; after the plasma treatment of the present invention, the defects in the aging area of ​​the insulation surface are obviously filled and covered, forming a granular deposit with excellent deposition effect, and the surface roughness is increased, such as Figure 6 (b) in the figure; however, after being treated by a conventional plasma jet reactor, the reactor energy is insufficient, the reaction medium is not fully activated, and a good granular deposit is not formed. The surface shows an uneven block deposit, such as Figure 6 (c) in .

[0070] The comparison results of water contact angle on the material surface before and after plasma treatment are as follows: Figure 7 As shown, it can be seen that the water contact angle of the untreated material surface is 109.157°. Figure 7 (a) in the present invention, after being treated by the device and method, the water contact angle is greatly increased to 121.237°. Figure 7 (b) in the figure achieves hydrophobic modification of the insulating surface. However, conventional plasma treatment devices will cause the insulating surface to lose its hydrophobicity, and its surface water contact angle will be greatly reduced to 74.410°, such as Figure 7 (c) in .

[0071] Therefore, the present invention utilizes plasma spraying modification technology to simply and quickly improve the performance of cable sheaths, improve the electrical performance of cable systems, extend the service life of existing power transmission and distribution cables, and improve various performances. At the same time, the present invention can be extended to other practical materials for insulation of power systems. The medium used is specified, and the specific values ​​of the reactor parameters and power supply are determined to reduce errors caused by manual labor, thereby improving the safety and reliability of the treated cables.

[0072] Other technical features of this method are similar to those of the corresponding device for wide-width plasma treatment of hydrophobic modification of insulator surface, and will not be described in detail here.

[0073] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0074] Obviously, those skilled in the art can make various changes and modifications to the embodiments of the present invention without departing from the spirit and scope of the embodiments of the present invention. Thus, if these modifications and variations of the embodiments of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A plasma reactor for improving the performance of the aging area on the surface of a cable sheath, characterized in that: The plasma reactor (5) comprises a joint (51), one end of the joint (51) is connected to a pipeline, and the other end is connected to a reactor body, the reactor body comprises an extension part (53) and a reaction part (52), the length direction of the extension part (53) is arranged at an angle with a horizontal plane, a cable sheath (7) to be treated is horizontally placed below the reaction part (52), a ground electrode is located below the cable sheath (7) to be treated, and the reaction part (52) comprises a convex block (521) and a bottom surface (522), a reactor treatment area is formed between the bottom surface (522) and the cable sheath (7) to be treated, the convex block (521) is arranged upward along the bottom surface at the end of the extension part (53) and is parallel to the length direction of the extension part (53), a concave groove (523) is provided inside the convex block (521), a pressing block (6) is arranged in the concave groove (523), and a high-voltage electrode is placed in the concave groove (523) and fixed by the pressing block (6).

2. The plasma reactor for improving the performance of the cable sheath surface aging area according to claim 1, characterized in that: The bottom surface (522) comprises an end A (5221), wherein the end A (5221) is an end away from the extension portion (53) and parallel to the width direction of the extension portion (53), and a boss (54) is provided between the end A (5221) and the cable sheath (7) to be processed, and the boss (54) is in close contact with the cable sheath (7) to be processed. The boss (54) forms a certain height distance between the reactor processing area and the surface of the cable sheath (7) to be processed, and the height of the boss (54) is 2 to 3 mm.

3. The plasma reactor for improving the performance of the cable sheath surface aging area according to claim 2, characterized in that: The included angle α between the length direction of the extension part (53) of the plasma reactor and the horizontal plane is 15 to 25 degrees, that is, the high-voltage electrode and the ground electrode form an included angle of 15 to 25 degrees.

4. The plasma reactor for improving the performance of the cable sheath surface aging area according to claim 3, characterized in that: The height of the boss (54) is 2.82 mm, so that the extension portion (53) of the plasma reactor forms an angle of 20° with the surface of the cable sheath (7) to be treated, and the high-voltage electrode and the ground electrode also form an angle of 20°.

5. The plasma reactor for improving the performance of the cable sheath surface aging area according to claim 1, characterized in that: A through hole (5211) is provided on the protrusion (521) close to the extension portion (53); the through hole (5211) is connected to the surrounding groove (523) to form a connection channel between the high-voltage electrode and the high-voltage line.

6. The plasma reactor for improving the performance of the cable sheath surface aging area according to claim 1, characterized in that: The shortest distance between the high-voltage electrode and the cable sheath (7) to be processed is controlled to be 3-5 mm.

7. A device for improving the performance of the aging area on the surface of a cable sheath, characterized in that: The device comprises an argon gas bottle (1), a first flow meter (21), a second flow meter (22), an anti-backflow bottle (3), a medium bottle (4) and a plasma reactor (5) according to any one of claims 1 to 6, wherein the output gas of the argon gas bottle (1) is divided into two parts, the first gas path passes through the first flow meter (21) and enters the anti-backflow bottle (3), and is then connected to the medium bottle (4), and the second gas path passes through the second flow meter (22) and is directly connected to the medium bottle (4), and the medium is taken out by the bubbling method and then merged with the first gas path, and is passed into the plasma reactor (5) through a joint (51). When ready, a pulse source is turned on, and discharge is observed to ensure that the surface (7) of the cable sheath to be treated can fully contact with the reactor treatment area of ​​the plasma reactor (5), so as to ensure the uniformity of the formed thin film.

8. A method for improving the performance of the aged area on the surface of a cable sheath, characterized in that: The method uses the device as claimed in claim 7, and specifically comprises the following steps: Step S1: clean the cable protective cover (7) to be processed and make it completely fit with the plasma reactor (5); Step S2: Open the argon gas bottle (1), adjust the flow rate of the first flow meter (21), and allow the argon gas to directly flow into the plasma reactor (5). During the waiting period, confirm whether the wind speed of the corresponding reaction part (52) is stable and whether there is any blockage. If both are in good condition, turn on and adjust the relevant parameters of the pulse source to send data, and observe whether the discharge is normal. If it is stable, turn off the power supply and close the second flow meter (22). Step S3: adjusting the flow rate of the second flow meter (22) so that the argon gas is sequentially introduced into the anti-backflow bottle (3) and the medium bottle (4), and bubbles are generated in the medium bottle (4). Observing whether the bubble generation is stable; if the bubble generation is stable, wait until the medium completely removes all the original air in the gas path, and then slowly adjusting the first flow meter (21) to the corresponding flow rate. During the adjustment, always pay attention to the liquid level in the conduit of the anti-backflow bottle (3) and the medium bottle (4) to avoid backflow; Step S4: after adjusting the flow rate of argon gas and the flow rate of the medium, if the bubbles are still in a stable state, turn on and adjust the relevant parameters of the pulse source and send data to observe whether the discharge is normal at this time, and ensure that the cable sheath surface (7) can fully contact the reactor processing area of ​​the plasma reactor (5) to ensure the uniformity of the formed film; Step S5 continues the reaction for several minutes, and continuously optimizes the relevant parameters of the pulse source and the flow rate ratio of argon gas to the medium until the best modification of the insulating surface of the cable protective sheath (7) to be treated is achieved.

9. The method for improving the performance of the aged area on the surface of a cable sheath according to claim 8, characterized in that: The relevant parameters of the pulse source after optimization are: voltage amplitude is 17~20kV, adjustment frequency is 6~8kHz, rising edge and falling edge are both 100~200ns; the optimized argon and medium flow rate ratio is: 1~2L / min argon and 15~25ml / min medium.

10. The method for improving the performance of the aged area on the surface of a cable sheath according to claim 8 or 9, characterized in that: The medium in the medium bottle (4) is n-hexane.

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