Partitioned coating non-linear conductive coating for basin-type insulator and preparation method of partitioned coating non-linear conductive coating

Abstract

The invention belongs to the technical field of direct-current basin-type insulator coatings, and particularly relates to a partition coating nonlinear conductive coating for a basin-type insulator and a preparation method of the partition coating nonlinear conductive coating. The preparation method comprises the following steps: firstly, carrying out surface pretreatment on barium titanate by adopting an effective technology, then adding necessary ingredients such as a curing agent and an accelerant into a polymer matrix, mixing and stirring the barium titanate and the polymer matrix added with the ingredients to obtain a mixed solution, and meanwhile, ensuring that air and impurities in the mixture are effectively removed by adopting a vacuum degassing technology; and preparing a composite coating and coating the surface of the insulator model with the composite coating, wherein the average thickness of the obtained coating is about 100 microns. On the basis of the prepared coating, the sample has good interface charge dissipation characteristics and performance of improving the along-surface insulation strength, coating can be achieved on the insulator, a new method is provided for charge suppression and electric field regulation and control of the basin-type insulator, the development prospect is wide, and the method is expected to be further popularized in the fields of chemical fundamental research and industrial application.

Description

Technical Field

[0001] The present invention belongs to the field of high-voltage transmission lines in the power system, and particularly relates to a partitioned coating of a non-linear conductance coating for a pot insulator and a preparation method thereof. Background Art

[0002] In recent years, the transformation to green and low-carbon energy has become an important strategic goal for the economic and social development of our country. High-voltage direct current (HVDC) transmission technology is an important physical support for the grid connection of new energy and the safe and stable operation of large power grids. Gas insulated transmission lines (GIL) have gradually become an important equipment support for energy transmission due to their many advantages such as small volume, high current-carrying capacity, and wide application range, and have received increasing attention from the academic and industrial circles. Although GIL gas insulated transmission equipment has been widely used, insulation faults are still the main cause of equipment failures, resulting in safety and economic losses, and are more complex and severe under DC operating conditions.

[0003] Insulator interface insulation is the weak link in the DC pipeline transmission composite insulation system. Under DC electrical stress, charge accumulation is likely to occur at the insulator gas-solid interface, increasing the electrical stress on the insulator surface. At the same time, the temperature gradient field formed by the high-voltage conductor in the pipeline will cause the conductivity of the insulator to be affected by temperature, resulting in changes in the tangential and normal field strengths, further exacerbating charge accumulation and easily leading to insulator interface insulation failure and ablation faults. Therefore, it is necessary to carry out innovative research on the design theory and method for suppressing surface charge accumulation on pot insulators. The academic community generally believes that surface treatment technology is an effective means to improve the electrical performance of the DC pipeline transmission composite insulation system. Therefore, the core of improving the surface insulation strength lies in the need to carry out interface charge regulation to suppress surface charge accumulation and reduce the interface electric field distortion caused by charges. Based on the above technical background, the present invention proposes a partitioned coating of a non-linear conductance coating for a pot insulator and a preparation method thereof by using numerical simulation. Summary of the Invention

[0004] Based on the above technical background, the present invention proposes a partitioned coating of a non-linear conductance coating for a pot insulator and a preparation method thereof. To achieve the above object, the present invention adopts the following technical solutions:

[0005] This process first performs surface pretreatment on barium titanate to improve its bonding ability with the polymer matrix and remove organic solvents that may affect performance. Subsequently, necessary ingredients such as curing agents and accelerators are added to the polymer matrix, which are crucial for the subsequent curing process. Then, barium titanate is mixed and stirred with the polymer matrix added with ingredients to obtain a mixed solution. At the same time, vacuum degassing technology is adopted to ensure that air and impurities in the mixture are effectively removed, thereby improving the purity and performance of the material. After mixing and degassing are completed, the obtained mixture is potted in a dust-free environment to prevent the intrusion of external pollutants. Next, through the temperature-rising curing step, the polymer matrix in the mixture undergoes a chemical reaction to form a stable cross-linked structure. Finally, a fluorine-containing coating material is coated on the surface of the insulator model using an automatic coating machine, and the average thickness of the coating is about 100 μm to ensure that it meets specific application requirements. The entire process ensures the uniformity, stability, and high performance of the final material by precisely controlling the conditions and parameters of each step, providing a reliable material solution for various application fields.

[0006] A partitioned coating non-linear conductance coating for pot-type insulators and its preparation method. The specific experimental steps are as follows:

[0007] (1) Weigh a certain amount of silane coupling agent 3-aminopropyltriethoxysilane coupling agent (KH-550) and a certain amount of inorganic filler barium titanate using a precision balance. Then weigh a certain amount of absolute ethanol as the organic environment for the reaction to occur. Add the three reagents into a flask and use a magnetic stirrer to mix and stir to perform surface pretreatment of the filler with the silane coupling agent.

[0008] (2) Weigh a certain amount of epoxy resin E51 and curing agent methyltetrahydrophthalic anhydride MTHPA, mix them with barium titanate fillers of different concentrations, and magnetically stir in a constant-temperature water bath for 60 min to enable the barium titanate particles to be evenly dispersed and ensure the volatilization of absolute ethanol, avoiding pores and impurities and improving the performance of the composite material.

[0009] (3) Secondly, add accelerator 2,4,6-tris(dimethylaminomethyl)phenol DMP-30 and stir well. Then place the well-stirred mixed solution in a vacuum drying oven to evacuate and remove bubbles.

[0010] (4) After the mixed solution is vacuum degassed, slowly pour the mixed solution into a mold in a dust-free environment. The composite material undergoes a cross-linking curing reaction in an oven with a stepwise temperature rise. After curing, it can be demolded to obtain an E51 / K-BT composite modified sample.

[0011] (5) Wipe the surface of the insulator with absolute ethanol to remove surface impurities.

[0012] (6) After the absolute ethanol has completely evaporated, spray guns are used to separately apply composite coating materials of different concentrations to the surface of the insulator model in zones. The average thickness of the prepared coating is about 100 μm.

[0013] In step (1), the ratio of the silane coupling agent 3-aminopropyltriethoxysilane coupling agent (KH-550) to the inorganic filler barium titanate is 3:100. The mixing and stirring time using a magnetic stirrer for surface pretreatment of the inorganic filler barium titanate is 60 min.

[0014] In step (2), the mass fraction of the filler is based on the mass of epoxy resin E51. The constant temperature water bath temperature is 60 °C, magnetic stirring is carried out for 60 min, and the rotation speed is set at 700 r / min.

[0015] In step (3), the mass of the accelerator added is ensured such that the mass ratio of epoxy resin:curing agent:accelerator is 100:85:1, and the time for vacuum degassing of bubbles is not less than 30 min.

[0016] In step (4), the time and temperature for stepwise temperature rise curing are: 80 °C × 2 h + 100 °C × 4 h + 120 °C × 4 h.

[0017] Advantages of the patent

[0018] 1. Uniform electric field distribution: Applying coatings in zones can precisely regulate the electric field, reduce local electric field concentration, improve insulation performance, and extend service life;

[0019] 2. Flexible and controllable process: The preparation method can flexibly design coating parameters according to requirements, precisely regulate the thickness and conductivity, and meet diverse needs;

[0020] 3. Optimized heat dissipation performance: The coating can be designed with heat conduction performance as required, reduce the internal temperature of the insulator, reduce power loss, and improve operating efficiency;

[0021] 4. Strong anti-fouling ability: The coating has non-linear conductive characteristics, can effectively block fouling erosion, prevent flashover faults, and adapt to harsh environments;

[0022] 5. Strong anti-aging performance: The coating material has strong weather resistance, can resist environmental erosion, reduce aging and cracking, and reduce maintenance costs;

[0023] 6. It is completely possible to successfully coat the insulator with epoxy resin as the matrix, has great development prospects, and is expected to be further promoted in the fields of chemical basic research and industrial applications; Brief description of the drawings

[0024] Figure 1 It is the process of the hydrolysis reaction of the silane coupling agent and the combination with barium titanate.

[0025] Figure 2It is a schematic diagram of the preparation process of the coating sample piece.

[0026] Figure 3 It is a coating partition diagram of the pot-type insulator. Detailed implementation manners

[0027] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below.

[0028] A preparation method for a partition-coated non-linear conductance coating for a pot-type insulator is as follows:

[0029] (1) Weigh a certain amount of silane coupling agent 3-aminopropyltriethoxysilane coupling agent (KH-550) and a certain amount of inorganic filler barium titanate with a precision balance. Then weigh a certain amount of absolute ethanol as the organic environment for the reaction to occur. Add the three reagents into a flask and use a magnetic stirrer to mix and stir to perform surface pretreatment of the filler with the silane coupling agent. Ensure that the ratio of the silane coupling agent 3-aminopropyltriethoxysilane coupling agent (KH-550) to the inorganic filler barium titanate is 3:100. The time for mixing and stirring using a magnetic stirrer during the surface pretreatment of the inorganic filler barium titanate is 60 min.

[0030] (2) Weigh a certain amount of epoxy resin E51 and curing agent methyltetrahydrophthalic anhydride MTHPA. The mass fraction of the filler is based on the mass of the epoxy resin E51 and is mixed with barium titanate fillers of different concentrations. Stir magnetically in a water bath at a constant temperature of 60 °C for 60 min, and set the rotation speed to 700 r / min to enable the barium titanate particles to be evenly dispersed, and ensure the volatilization of absolute ethanol to avoid pores and impurities and improve the performance of the composite material.

[0031] (3) Secondly, add accelerator 2,4,6-tris(dimethylaminomethyl)phenol DMP-30 and stir well. Then put the well-stirred mixed solution into a vacuum drying oven to evacuate and remove the bubbles. Ensure that the mass of the accelerator is such that the mass ratio of epoxy resin:curing agent:accelerator is 100:85:1, and the time for evacuating and removing the bubbles is not less than 30 min.

[0032] (4) After the mixed solution is vacuum degassed, slowly pour the mixed solution into a mold in a dust-free environment. The composite material is subjected to a stepwise temperature increase in an oven (80 °C × 2 h + 100 °C × 4 h + 120 °C × 4 h) for crosslinking and curing reaction. After curing, it can be demolded to obtain an E51 / K-BT composite modified sample piece.

[0033] (5) Wipe the surface of the insulator with absolute ethanol to remove surface impurities.

[0034] After the absolute ethanol is completely evaporated, the composite coating materials with different concentrations are respectively coated on the surface of the insulator model in zones by using a spray gun, and the average thickness of the prepared coating is about 100 μm.

[0035] The above-described embodiments are only one implementation manner of the present invention, and are described with a certain degree of specificity and detail, but should not be construed as limiting the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several deformations and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the invention patent shall be subject to the appended claims.

Claims

1. A nonlinear conductive coating for partition coating of pot-type insulators and a preparation method thereof, characterized in that: The specific experimental steps are as follows: (1) A certain amount of silane coupling agent 3-aminopropyltriethoxysilane coupling agent (KH-550) and a certain amount of inorganic filler barium titanate are weighed on a precision balance, and a certain amount of anhydrous ethanol is weighed as an organic environment for the reaction. The three reagents are added into a flask and mixed and stirred using a magnetic stirrer so that the silane coupling agent pre-treats the surface of the filler. (2) A certain amount of epoxy resin E51 and curing agent methyltetrahydrophthalic anhydride MTHPA were weighed and mixed with barium titanate fillers of different concentrations, and magnetically stirred in a constant temperature water bath for 60 minutes to ensure that the barium titanate particles can be evenly dispersed and the anhydrous ethanol is volatilized to avoid pores and impurities, thereby improving the performance of the composite material. (3) Next, add the promoter 2,4,6-tris(dimethylaminomethyl)phenol DMP-30 and stir thoroughly. Then, place the stirred mixed solution in a vacuum drying oven to remove air bubbles. (4) After the mixed solution is vacuum degassed, the mixed solution is slowly poured into a mold in a dust-free environment. The composite material is step-heated in an oven to undergo a cross-linking and curing reaction. After curing, it can be demolded to obtain an E51 / K-BT composite modified sample. (5) Wipe the surface of the insulator with anhydrous ethanol to remove surface impurities. (6) After the anhydrous ethanol is completely evaporated, the composite coating material with different concentrations is coated on the surface of the insulator model in different areas using a spray gun. The average thickness of the prepared coating is about 100 μm.

2. The nonlinear conductive coating for partition coating of pot-type insulators and the preparation method thereof according to claim 1, characterized in that: The ratio of the silane coupling agent 3-aminopropyltriethoxysilane coupling agent (KH-550) to the inorganic filler barium titanate in step (1) is 3:

100. When the surface of the inorganic filler barium titanate is pretreated, the mixing and stirring time using a magnetic stirrer is 60 minutes.

3. The nonlinear conductive coating for partition coating of pot-type insulators and the preparation method thereof according to claim 1, characterized in that: The mass fraction of the filler in step (2) is based on the mass of epoxy resin E51, the constant temperature water bath temperature is 60°C, the magnetic stirring is 60 minutes, and the speed is set to 700r / min.

4. The nonlinear conductive coating for partition coating of pot-type insulators and the preparation method thereof according to claim 1, characterized in that: The mass ratio of the accelerator added in step (3) is ensured to be 100:85:1, and the vacuum degassing time is not less than 30 minutes.

5. The nonlinear conductive coating for partition coating of pot-type insulators and the preparation method thereof according to claim 1, characterized in that: The time and temperature for gradually heating and curing in step (4) are: 80°C×2h+100°C×4h+120°C×4h.

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