A polishing method for improving the surface flashover performance of a three-column insulator

Abstract

The present application relates to the field of insulating material surface modification, and particularly to a polishing method for improving the surface flashover performance of a three-column insulator, which comprises longitudinally dividing into equidistant annular regions; cleaning the surface of the three-column insulator, measuring the potential, surface conductivity and roughness of each region of the three-column insulator; and polishing in gradient from the high-voltage end to the grounding end. The polishing method for improving the surface flashover performance of a three-column insulator can improve the modification efficiency and modification results of large three-column insulators.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of surface modification of insulating materials, and particularly to a polishing method for improving the surface flashover performance of a three-column insulator. BACKGROUND

[0002] Three-column insulators are widely used as a good choice for solving the problem of power transmission in power plants due to their high reliability and strong transmission capacity. However, three-column insulators inevitably bear complex electric, thermal, and mechanical coupling stresses during long-term operation in high-voltage and high-power environments, which may lead to insulation degradation and even failure under the induction of local defects. Therefore, surface modification of three-column insulators is of great significance.

[0003] Currently, the surface modification methods for insulators mainly include thin film deposition, surface coating, and traditional uniform sandpaper polishing. However, these methods are inefficient and unsatisfactory in terms of modification results for large three-column insulators. SUMMARY

[0004] In view of the above or existing problems in the prior art, the present application is proposed.

[0005] Therefore, the purpose of the present application is to provide a polishing method for improving the surface flashover performance of a three-column insulator, which can solve the problems of low modification efficiency and unsatisfactory modification results of large three-column insulators.

[0006] To solve the above technical problems, the present application provides the following technical solutions: a polishing method for improving the surface flashover performance of a three-column insulator, which includes performing longitudinal equidistant annular region segmentation; cleaning the surface of the three-column insulator, measuring the potential, surface conductivity, and roughness of each region of the three-column insulator; and performing gradient polishing from the high-voltage end to the grounded end.

[0007] As a preferred solution of the polishing method for improving the surface flashover performance of a three-column insulator, the longitudinal equidistant annular region segmentation includes:

[0008] Each single column of the three-column insulator is divided into 10 annular regions by equidistant division, and the annular width length formula and the longitudinal equidistant annular region area formula are as follows

[0009]

[0010] S n =2πR n d n

[0011] d n is the width of the nth region from the high-voltage end to the grounded end.

[0012] L is the total length of the single-post insulator;

[0013] S n is the area of ​​the nth region from the high voltage end to the ground end;

[0014] R n is the average radius of the nth area from the high voltage end to the ground end.

[0015] As a preferred solution of the polishing method for improving the surface flashover performance of three-pillar insulators described in the present invention, the measuring of the potential of each area of ​​the pillar insulator includes: applying a voltage of 1000V DC to the surface of the single-pillar insulator before modification, using an electrostatic potential probe, and performing 10 measurements at constant room temperature and indoor humidity to obtain the average potential of the area.

[0016] As a preferred solution of the polishing method for improving the surface flashover performance of three-pillar insulators according to the present invention, wherein: the measuring of the surface conductivity of the pillar insulator includes:

[0017] The applied voltage was 1000 V DC, the recording step was 3 min, and 10 measurements were performed at constant room temperature and humidity. The average value was taken and the conductivity σ was calculated using the following formula: s , the formula is as follows

[0018]

[0019] Where D1 and D2 are the diameters of the measuring electrode and the guard electrode, V a and I a are the applied DC voltage and measured current, respectively.

[0020] As a preferred solution of the polishing method for improving the surface flashover performance of three-pillar insulators described in the present invention, the measuring of the surface roughness of the pillar insulator includes: the surface roughness of the pillar insulator before modification, and its roughness is characterized by Ra (arithmetic average surface roughness) and root mean square surface roughness (Rrms).

[0021] As a preferred solution of the polishing method for improving the surface flashover performance of three-pillar insulators described in the present invention, the gradient polishing from the high-voltage end to the grounding end includes: polishing with different strengths and degrees from the high-voltage end to the grounding end according to the different potentials and conductivity to form a gradient roughness.

[0022] As a preferred solution of the polishing method for improving the surface flashover performance of three-pillar insulators according to the present invention, the cleaning of the surface of the pillar insulator includes wiping with 75% anhydrous ethanol and air-drying for 10 minutes.

[0023] As a preferred solution of the polishing method for improving the surface flashover performance of three-pillar insulators described in the present invention, the measuring of the potential, surface conductivity and roughness of each area of ​​the pillar insulator includes: maintaining the temperature and humidity of the environment in which the pillar insulator is located unchanged.

[0024] As a preferred solution of the polishing method for improving the surface flashover performance of three-pillar insulators according to the present invention, the polishing method for improving the surface flashover performance of three-pillar insulators further includes: judging whether all the modified single-pillar insulators have been completely modified.

[0025] As a preferred solution of the polishing method for improving the surface flashover performance of three-pillar insulators described in the present invention, the polishing method for improving the surface flashover performance of three-pillar insulators further includes: performing a flashover performance test and comparison between the modified three-pillar insulator and the unmodified three-pillar insulator.

[0026] The beneficial effects of the present invention are as follows: the polishing method for improving the surface flashover performance of a three-pillar insulator according to the present invention can improve the modification efficiency and modification results of large three-pillar insulators. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort. Among them:

[0028] Fig. 1 Schematic diagram of the overall structure of the grinding method for improving the surface flashover performance of three-pillar insulators;

[0029] Fig. 2 Cross-sectional view of the grinding method for improving the surface flashover performance of three-pillar insulators. DETAILED DESCRIPTION

[0030] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0031] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0032] Secondly, the term "one embodiment" or "embodiment" herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in various places throughout this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive of other embodiments.

[0033] Example 1

[0034] Reference Figs. 1-2 , which is the first embodiment of the present invention, provides a polishing method for improving the surface flashover performance of three-pillar insulators, specifically including dividing the longitudinal equidistant annular areas into blocks; cleaning the surface of the post insulator, measuring the potential, surface conductivity and roughness of each area of ​​the post insulator; and performing gradient polishing from the high-voltage end to the grounding end.

[0035] Furthermore, performing longitudinal equidistant annular area segmentation includes equidistantly dividing each single-pillar insulator of the three-pillar insulator into 10 annular areas.

[0036] Furthermore, measuring the potential of each area of ​​the post insulator includes: applying a voltage of 1000V DC on the surface of the single post insulator before modification, using an electrostatic potential probe, and performing 10 measurements at constant room temperature and indoor humidity to obtain an average potential value of the area.

[0037] Preferably, measuring the surface conductivity of the post insulator includes: applying a voltage of 1000 V DC, recording in steps of 3 minutes, performing 10 measurements at constant room temperature and humidity, taking an average value, and calculating the conductivity using the following formula.

[0038] In this embodiment, the present invention provides a polishing method for improving the surface flashover performance of a three-pillar insulator. The method divides a single-pillar insulator of the three-pillar insulator into longitudinally equidistant annular blocks, and tests the conductivity and roughness of each area. Gradient polishing of different degrees is performed based on the different conductivity between the high-voltage section and the grounding end and the different roughness of each annular block, thereby obtaining a gradient roughness distribution.

[0039] Example 2

[0040] Reference Figs. 1-2 , which is the second embodiment of the present invention, and is based on the previous embodiment.

[0041] Specifically, first obtain a three-pillar insulator in any GIL transmission pipeline, wipe it with 75% anhydrous ethanol, and air-dry it for 10 minutes.

[0042] Furthermore, the three-pillar insulator has three single pillars in total, and it is determined whether the number of modified single pillar insulators is 3 (i.e. whether all modifications are completed). If the number of modified single pillar insulators is not 3, enter Fig. 1 In the step of "dividing any unmodified single-pillar insulator into longitudinal equidistant annular areas"; if the number of modified single-pillar insulators is 3, enter Fig. 1 Follow the steps in "Flashover performance test and comparison with unmodified three-pillar insulators" in the .

[0043] Furthermore, since the modified single-pillar insulator is not 3, any unmodified single-pillar insulator is selected and the length L of 2-6 single-pillar insulators is measured, and the ring width can be obtained. At the same time, the area S of the longitudinal equidistant annular region is obtained. n =2πR n d n .

[0044] Furthermore, after obtaining the annular width and the area of ​​the longitudinally equidistant annular regions, the conductivity and roughness tests of each block region from n1 to n10 are performed. In this embodiment, a polishing method for improving the surface flashover performance of a three-pillar insulator is described. The surface conductivity of the pillar insulator before modification is measured by applying a voltage of 1000V DC to the n1 region, with a recording step length of 3 minutes. Ten measurements are performed at constant room temperature and indoor humidity, and the average value is taken to obtain the conductivity of the n1 region. Similarly, all conductivities from n1 to n10 are obtained. At the same time, the surface roughness is measured at 10 different locations in any region from n1 to n10, and the average value is used as the actual roughness value, thereby obtaining all roughness values ​​from n1 to n10 for comparison after modification. At the test point, a voltage of 1000V DC is applied, and an electrostatic potential probe is used to perform 10 measurements at constant room temperature and indoor humidity to obtain the average value of the region. Examples of simulated data are shown in Table 1.

[0045] Table 1

[0046]

[0047] Furthermore, Table 1 shows that the potential range increases from n10 to n1, indicating that the degree of charge accumulation also increases. Therefore, this three-post insulator is not suitable for uniform grinding. Therefore, the new annular profile grinder of the present invention was used to grind n10 to n1. The grinding force was gradually increased, resulting in a gradually increasing roughness gradient.

[0048] Preferably, after all modifications, the flashover performance is tested in comparison with the unmodified three-strand insulator. The high voltage end is connected to a high voltage DC power supply and the grounded end is connected to ground until flashover occurs. The oscilloscope is used to record the ten flashover voltages and the average is taken.

[0049] It is to be understood that the development process can involve various steps that need not be performed in any particular order or according to any pre-determined pattern, and that they can involve repeated testing of the subject specification against the performance of the subject specification, and against the performance of other known or conceptualizations in the technical field of the subject specification.

[0050] It should be noted that the above examples are merely used to illustrate the technical solutions of the present application, rather than limit the present application. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or equivalently replaced, without departing from the spirit and scope of the technical solutions of the present application, and they should be covered in the scope of the claims of the present application.

Claims

1. A polishing method for improving the surface flashover performance of a three-pillar insulator, characterized by: include, Divide the area into blocks with equal distance in the longitudinal direction; Clean the surface of the post insulator and measure the potential, surface conductivity and roughness of each area of ​​the post insulator; Gradient grinding is performed from the high voltage end to the ground end; The longitudinal equidistant annular area segmentation comprises: Each single-pillar insulator of the three-pillar insulator is equally divided into 10 annular areas. The formula for the length of the annular width and the area formula for the longitudinally equidistant annular areas are as follows: ； ； is the width of the nth region from the high voltage end to the ground end; is the total length of the single-post insulator; is the area of ​​the nth region from the high voltage end to the ground end; is the average radius of the nth area from the high voltage end to the ground end; Measuring the potential of each area of ​​the post insulator includes: Before modification, a voltage of 1000V DC was applied to the surface of the single-pillar insulator. Ten measurements were performed using an electrostatic potential probe at constant room temperature and humidity to obtain the average potential value of the area. The measuring of the surface conductivity of the post insulator comprises: The applied voltage was 1000 V DC, the recording step was 3 min, and 10 measurements were performed at constant room temperature and humidity. The average value was taken and the conductivity was calculated using the following formula: , the formula is as follows: ； Where D1 and D2 are the diameters of the measuring electrode and the guard electrode, and are the applied DC voltage and measured current, respectively; The measuring of the surface roughness of the post insulator comprises: The surface roughness of the post insulator before modification is characterized by Ra (arithmetic average surface roughness) and root mean square surface roughness (Rrms); The gradient polishing from the high voltage end to the ground end includes: From the high-voltage end to the ground end, different strengths and degrees of grinding are performed according to the different potentials and conductivity to form a gradient roughness.

2. The polishing method for improving the surface flashover performance of a three-pillar insulator according to claim 1, characterized in that: The cleaning of the post insulator surface comprises: Wipe with 75% anhydrous ethanol and air dry for 10 minutes.

3. The polishing method for improving the surface flashover performance of a three-pillar insulator according to claim 2, characterized in that: The measuring of the potential, surface conductivity and roughness of each area of ​​the post insulator includes: Keep the temperature and humidity of the environment where the post insulator is located constant.

4. The polishing method for improving the surface flashover performance of a three-pillar insulator according to claim 3, characterized in that: The polishing method for improving the surface flashover performance of the three-pillar insulator further includes: Determine whether all modified single-pillar insulators have been modified.

5. The polishing method for improving the surface flashover performance of a three-pillar insulator according to claim 4, characterized in that: The polishing method for improving the surface flashover performance of the three-pillar insulator further includes: The flashover performance of the modified three-pillar insulator was compared with that of the unmodified three-pillar insulator.

Images