CN117452165A - Composite insulator surface insulation performance evaluation method based on novel leakage current separation technology - Google Patents
Composite insulator surface insulation performance evaluation method based on novel leakage current separation technology Download PDFInfo
- Publication number
- CN117452165A CN117452165A CN202311543341.9A CN202311543341A CN117452165A CN 117452165 A CN117452165 A CN 117452165A CN 202311543341 A CN202311543341 A CN 202311543341A CN 117452165 A CN117452165 A CN 117452165A
- Authority
- CN
- China
- Prior art keywords
- leakage current
- discharge
- current
- composite insulator
- dry
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000012212 insulator Substances 0.000 title claims abstract description 44
- 239000002131 composite material Substances 0.000 title claims abstract description 33
- 238000000926 separation method Methods 0.000 title claims abstract description 28
- 238000009413 insulation Methods 0.000 title claims abstract description 22
- 238000011156 evaluation Methods 0.000 title claims abstract description 19
- 238000005516 engineering process Methods 0.000 title claims abstract description 12
- 229920002379 silicone rubber Polymers 0.000 claims abstract description 38
- 238000012360 testing method Methods 0.000 claims abstract description 31
- 150000003839 salts Chemical class 0.000 claims abstract description 30
- 230000032683 aging Effects 0.000 claims abstract description 29
- 239000007921 spray Substances 0.000 claims abstract description 27
- 239000004945 silicone rubber Substances 0.000 claims abstract description 23
- 238000000034 method Methods 0.000 claims abstract description 20
- 238000004458 analytical method Methods 0.000 claims abstract description 13
- 239000000463 material Substances 0.000 claims abstract description 11
- 238000001941 electron spectroscopy Methods 0.000 claims abstract description 8
- 239000000126 substance Substances 0.000 claims abstract description 8
- 238000004833 X-ray photoelectron spectroscopy Methods 0.000 claims abstract 4
- 238000010891 electric arc Methods 0.000 claims description 40
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 13
- 239000000945 filler Substances 0.000 claims description 9
- 238000002186 photoelectron spectrum Methods 0.000 claims description 7
- 229910018540 Si C Inorganic materials 0.000 claims description 6
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 6
- 229920001971 elastomer Polymers 0.000 claims description 6
- 230000003628 erosive effect Effects 0.000 claims description 6
- 239000005060 rubber Substances 0.000 claims description 6
- 229910010271 silicon carbide Inorganic materials 0.000 claims description 6
- 230000003595 spectral effect Effects 0.000 claims description 6
- 150000004684 trihydrates Chemical class 0.000 claims description 6
- 238000001228 spectrum Methods 0.000 claims description 5
- 230000000694 effects Effects 0.000 claims description 4
- 230000005661 hydrophobic surface Effects 0.000 claims description 4
- 239000002861 polymer material Substances 0.000 claims description 4
- SMZOUWXMTYCWNB-UHFFFAOYSA-N 2-(2-methoxy-5-methylphenyl)ethanamine Chemical compound COC1=CC=C(C)C=C1CCN SMZOUWXMTYCWNB-UHFFFAOYSA-N 0.000 claims description 3
- NIXOWILDQLNWCW-UHFFFAOYSA-N 2-Propenoic acid Natural products OC(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 claims description 3
- 238000012544 monitoring process Methods 0.000 claims description 3
- 230000000977 initiatory effect Effects 0.000 claims 1
- 238000011109 contamination Methods 0.000 abstract description 5
- 230000006866 deterioration Effects 0.000 abstract description 4
- 239000000809 air pollutant Substances 0.000 abstract description 2
- 231100001243 air pollutant Toxicity 0.000 abstract description 2
- 238000005260 corrosion Methods 0.000 abstract description 2
- 230000007797 corrosion Effects 0.000 abstract description 2
- 238000003745 diagnosis Methods 0.000 abstract description 2
- 230000007613 environmental effect Effects 0.000 abstract description 2
- 239000000203 mixture Substances 0.000 description 4
- 229910004283 SiO 4 Inorganic materials 0.000 description 3
- 238000002405 diagnostic procedure Methods 0.000 description 2
- 239000004205 dimethyl polysiloxane Substances 0.000 description 2
- 235000013870 dimethyl polysiloxane Nutrition 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 230000005684 electric field Effects 0.000 description 2
- 230000002209 hydrophobic effect Effects 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- 229920000435 poly(dimethylsiloxane) Polymers 0.000 description 2
- 230000035945 sensitivity Effects 0.000 description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 1
- 239000003595 mist Substances 0.000 description 1
- CXQXSVUQTKDNFP-UHFFFAOYSA-N octamethyltrisiloxane Chemical compound C[Si](C)(C)O[Si](C)(C)O[Si](C)(C)C CXQXSVUQTKDNFP-UHFFFAOYSA-N 0.000 description 1
- 238000004987 plasma desorption mass spectroscopy Methods 0.000 description 1
- -1 polydimethylsiloxane Polymers 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/12—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing
- G01R31/1218—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing using optical methods; using charged particle, e.g. electron, beams or X-rays
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/12—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing
- G01R31/1227—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing of components, parts or materials
- G01R31/1245—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing of components, parts or materials of line insulators or spacers, e.g. ceramic overhead line cap insulators; of insulators in HV bushings
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Testing Relating To Insulation (AREA)
Abstract
The invention discloses a composite insulator surface insulation performance evaluation method based on a novel leakage current separation technology, which comprises the novel leakage current separation technology and the composite insulator surface insulation performance evaluation method. The novel leakage current separation technique is performed by Fast Fourier Transform (FFT). The leakage current is divided into three components based on experimentally defined discharge types. The method for evaluating the surface insulation performance of the composite insulator comprises the steps of observing two discharge phenomena in a salt spray aging test, performing chemical analysis (ESCA) on the surface of the composite insulator by using an electron spectroscopy, and then evaluating bonding conditions. In the case where silicone rubber is used as an outdoor insulator, various environmental factors such as ultraviolet rays, rainwater, and air pollutants may promote deterioration of material properties. During operation of the power system, tracking and corrosion phenomena are caused by electrical factors such as arc and corona partial discharge. The hydrophobicity is restored after a substantial period of "rest" even if the hydrophobicity is temporarily deteriorated during exposure to discharge or severe contamination. However, the electrical properties of such materials have not been fully elucidated for a long time. The invention establishes an evaluation index and a diagnosis method for the electric characteristics.
Description
Technical Field
The invention relates to a composite insulator surface insulation performance evaluation method based on a novel leakage current separation technology, in particular to a method for separating leakage current and detecting the insulation performance of silicon rubber, and belongs to the technical field of high voltage and insulation of power transmission lines.
Background
In recent years, silicon rubber composite insulator has been widely used in electric power systems because of its advantages such as light weight, high mechanical strength, high hydrophobicity, etc. However, in the case where silicone rubber is used as an outdoor insulator, various environmental factors such as ultraviolet rays, rainwater, and air pollutants may promote deterioration of material properties. Secondly, during operation of the power system, tracking and corrosion phenomena are caused by electrical factors such as arc and corona partial discharge.
Considerable research effort has been directed to the development of diagnostic methods to date. Diagnostic factors are mainly surface conductivity, hydrophobicity, equivalent Salt Deposition Density (ESDD), flashover voltage (FOV), and leakage current. Wherein the leakage current provides information about the amount of filth in the filth insulator, which has been studied and confirmed by a particular work group of the IEEE non-ceramic insulator filth work group.
In the salt spray aging test, two discharge phenomena are generally observed, and the insulating properties can be evaluated. One of them, corona partial discharge occurs between water droplets, and si—c bonds of silicone rubber are broken by photon energy, since photon energy generated by corona discharge is greater than bonding energy of si—c. Thus, the insulating surface condition can be defined by corona discharge activity of the hydrophobic surface. The other is a dry-charged arc discharge which occurs between dry-charged strips on the surface of the polymer material. The half width of the dry ribbon arc discharge current is about 1.5ms, and the accumulated charge is much greater than the corona discharge. Therefore, the dry ribbon arc discharge and the corona discharge have an important influence on the performance of the insulators, and it is necessary to study their characteristics in the salt spray aging test.
Disclosure of Invention
The hydrophobic properties are restored after a substantial period of "rest" even though they are temporarily deteriorated during exposure to discharge or severe contamination. However, the electrical properties of such materials have not been fully elucidated for a long time. The present invention aims to establish an evaluation index and a diagnosis method for such electrical characteristics.
The invention realizes the above purpose through the following technical scheme: a composite insulator surface insulation performance evaluation method based on a novel leakage current separation technology comprises the following steps:
leakage current, monitoring leakage current has the advantage of on-line evaluation. The leakage current provides information on the degree of contamination on the contaminated insulator, focusing on the relationship between discharge light emission and leakage current obtained in the salt spray aging test. The light emission from both discharges was observed using a spectroscope, photomultiplier and stationary camera, and then its characteristics were evaluated and compared with leakage current.
The separation technique separates the corona discharge component from the leakage current by Fast Fourier Transform (FFT). Based on experimentally defined discharge types, leakage currents are divided into three components, such as conductive current flowing in a water film on composite insulator material, corona discharge current and dry-charged arc discharge current. Finally, chemical analysis (ESCA) is carried out on the surface of the composite insulator by utilizing an electron spectroscopy. The composite insulator composition was then evaluated for changes.
The method for evaluating the surface insulation performance of the composite insulator comprises the following steps:
1) In the salt spray aging test, salt spray aging test at 1.1.1 3 Is carried out in an acrylic acid chamber of (2). Two kinds of silicone rubbers different in shape were used as insulator samples.
2) The separation of the corona discharge component from the leakage current is achieved using a Fast Fourier Transform (FFT). According to FFT analysis, the frequency range of corona discharge is above 5khz, while the frequency ranges of conductive arc discharge current and dry-charged arc discharge current are below 2 khz. Then, a current component of 2.5kHz or more is defined as a current component generated by corona discharge.
3) The onset of dry-charged arc discharge is determined by differential techniques, wherein a large rate of change of leakage current is used as an indicator. In addition, we assume that the conduction current is the difference between the leakage current and the corona discharge current plus the dry-charged arc discharge current.
4) During the salt spray test and after the end of the test, the light emission of the discharge phenomenon was observed using a still camera. To measure the spectral distribution of the discharge emission, a Spectroscope (SPM) is connected to a gated CCD camera. The output of the Photomultiplier (PM) was input to an oscilloscope and analyzed on a personal computer. In the observation of photomultipliers, blue and red filters were used to measure corona and dry-charged arc discharge. The spectrum of the dry charged discharge was observed with a Na filter.
5) Through salt spray aging test, ESCA is utilized to analyze photoelectron spectrum of Si. The photoelectron spectra of Si of the original RTV, exposed RTV and exposed HTV were observed.
The technical scheme of the invention is as follows: the separation of the corona discharge component and the leakage current is firstly carried out by Fast Fourier Transform (FFT); the insulating property evaluation method is to use an electron spectroscopy to carry out chemical analysis on the surface of the composite insulator.
The technical scheme of the invention is as follows: in the step 1), two kinds of silicone rubbers having different shapes are used, and one of them is a rod-shaped silicone rubber having a diameter of 30mm and a length of 250 mm. The other is a plate-shaped silicon rubber with the thickness of 2mm, and the cross section area of the plate-shaped silicon rubber is 80mm 2 . In addition, two different rod rubbers and fillers are usedAnd (3) seed rubber. One of them is high temperature vulcanized silicone rubber (HTV) with Alumina Trihydrate (ATH) and SiO as fillers. The ATH content was 50%. The other is room temperature vulcanized silicone Rubber (RTV), the filler is only SiO. SiO in silicone rubber acts to enhance performance, and Alumina Trihydrate (ATH) provides tracking and erosion resistance. The plate-shaped sample uses high temperature vulcanized silicone rubber (HTV).
The technical scheme of the invention is as follows: the leakage current is divided into three components, namely a conduction current, a dry-charged arc discharge current and a corona discharge current. The respective accumulated charges are calculated from these current components. In addition, electron spectroscopy was used to conduct chemical analysis (ESCA) on the composite insulator surface. The bonding conditions are then evaluated.
The technical scheme of the invention is as follows: in said step 4), the leakage current consists of a sine wave with a frequency of 60hz and several pulse components with a main pulse width of several tens of ns and several ms, for current pulses with a pulse width of several ms, the leakage current rapidly becomes large. The longer pulse width current pulse is a dry charged arc discharge bridging over a longer distance. The short time current pulse is a locally distributed corona discharge, wherein the total amount of charge generated by the corona discharge is less than the total amount of charge generated by a dry charged arc discharge.
The technical scheme of the invention is as follows: in the step 1), in the salt spray aging test, two discharge phenomena are generally observed to evaluate the insulation properties of the material. One of them is a corona (partial) discharge occurring between water droplets, in which Si-C bonds of the silicone rubber are broken by photon energy, because the photon energy generated by the corona discharge is greater than the energy of the Si-C bonds. Thus, the corona discharge activity on a hydrophobic surface can be used to define the insulation surface condition. The other is that the dry charge discharge occurs between the dry bands on the surface of the polymer material. The half width of the dry-charged arc discharge current is about 15ms, which may cause tracking and erosion phenomena, the accumulated charge of which is much greater than that of corona discharge.
The beneficial effects of the invention are as follows: 1) A novel leakage current separation technique is formed, and the separation of the corona discharge component and the leakage current is performed by Fast Fourier Transform (FFT). Based on experimentally defined discharge types, leakage currents are divided into three components, such as conductive current flowing in a water film on composite insulator material, corona discharge current and dry-charged arc discharge current.
2) To sufficiently clarify the electric characteristics recovered after the temporary deterioration of the water repellency, and to establish an evaluation index and a diagnostic method.
Drawings
FIG. 1 is a flow chart of a leakage current separation process according to the present invention;
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
As shown in FIG. 1, a novel leakage current separation technique comprises
1) Leakage current, monitoring leakage current has the advantage of on-line evaluation. The leakage current provides information on the degree of contamination on the contaminated insulator, focusing on the relationship between discharge light emission and leakage current obtained in the salt spray aging test. The light emission from both discharges was observed using a spectroscope, photomultiplier and stationary camera, and then its characteristics were evaluated and compared with leakage current.
2) The separation technique separates the corona discharge component from the leakage current by Fast Fourier Transform (FFT). Based on experimentally defined discharge types, leakage currents are divided into three components, such as conductive current flowing in a water film on composite insulator material, corona discharge current and dry-charged arc discharge current. Finally, chemical analysis (ESCA) is carried out on the surface of the composite insulator by utilizing an electron spectroscopy. The composite insulator composition was then evaluated for changes.
It should be noted that: the leakage current consists of a sine wave with a frequency of 60hz and several pulse components with a main pulse width of tens of ns and ms, and for current pulses with a pulse width of several ms, the leakage current rapidly increases. The longer pulse width current pulse is a dry charged arc discharge bridging over a longer distance. The short time current pulse is a locally distributed corona discharge, wherein the total amount of charge generated by the corona discharge is less than the total amount of charge generated by a dry charged arc discharge.
The method for evaluating the surface insulation performance of the composite insulator comprises the following steps:
first, salt spray aging test was conducted in 1.1.1 3 Is carried out in an acrylic acid chamber of (2). Two kinds of silicone rubbers different in shape were used as insulator samples.
Two kinds of silicone rubbers having different shapes were used, one of which was a rod-shaped silicone rubber having a diameter of 30mm and a length of 250 mm. The other is a plate-shaped silicon rubber with the thickness of 2mm, and the cross section area of the plate-shaped silicon rubber is 80mm 2 . In addition, two kinds of rubber different in rod rubber and filler are used. One of them is high temperature vulcanized silicone rubber (HTV) with Alumina Trihydrate (ATH) and SiO as fillers. The ATH content was 50%. The other is room temperature vulcanized silicone Rubber (RTV), the filler is only SiO. SiO in silicone rubber acts to enhance performance, and Alumina Trihydrate (ATH) provides tracking and erosion resistance. The plate-shaped sample uses high temperature vulcanized silicone rubber (HTV).
Table 1 shows experimental conditions of the salt spray aging test. The flow rate of the salt mist was 0.9l/h, and the water conductivity was 800. Mu.S/cm. The applied voltage was 15kV, the frequency was 60Hz, and the average electric field was 60V/mm. One aging period includes two operations of a salt spray aging period of 8 hours and a drying period of 16 hours, and then a total aging test time of 500 hours is set, a leakage current is measured every 15 minutes, and the leakage current is divided into three components of a conduction current, a dry-charge arc discharge current and a corona discharge current.
TABLE 1 test conditions in salt spray aging test
In the salt spray aging test, two discharge phenomena are generally observed to evaluate the insulating properties of the material. One of them is a corona (partial) discharge occurring between water droplets, in which Si-C bonds of the silicone rubber are broken by photon energy, because the photon energy generated by the corona discharge is greater than the energy of the Si-C bonds. Thus, the corona discharge activity on a hydrophobic surface can be used to define the insulation surface condition. The other is that the dry charge discharge occurs between the dry bands on the surface of the polymer material. The half width of the dry-charged arc discharge current is about 15ms, which may cause tracking and erosion phenomena, the accumulated charge of which is much greater than that of corona discharge.
Second, the separation of the corona discharge component from the leakage current is achieved using a Fast Fourier Transform (FFT). According to FFT analysis, the frequency range of corona discharge is above 5kHz, while the frequency range of conductive arc discharge current and dry-charged arc discharge current is below 2 kHz. Then, a current component of 2.5kHz or more is defined as a current component generated by corona discharge.
Third, the onset of dry-charged arc discharge is determined by differential techniques, wherein a large rate of change of leakage current is used as an indicator. In addition, we assume that the conduction current is the difference between the leakage current and the corona discharge current plus the dry-charged arc discharge current.
Fourth, light emission of discharge phenomenon was observed using a still camera during the salt spray test and after the end of the test. To measure the spectral distribution of the discharge emission, a Spectroscope (SPM) is connected to a gated CCD camera. The output of the Photomultiplier (PM) was input to an oscilloscope and analyzed on a personal computer. In the observation of photomultipliers, blue and red filters were used to measure corona and dry-charged arc discharge. The spectrum of the dry charged discharge was observed with a Na filter.
In this case, the CCD camera can enhance the optical signal by about 10 4 The threshold time may vary from 5ns to 1 s. The photomultiplier is side window type, and the spectral sensitivity is 300-800 nm.
Fifth, through salt spray aging test, the photoelectron spectrum of Si was analyzed by ESCA. The photoelectron spectra of Si of the original RTV, exposed RTV and exposed HTV were observed.
Example 1
The embodiment takes the leakage current detection condition of the 500KV line strain tower composite insulator governed by Yichang operation and maintenance part as an example.
In this embodiment, a Spectroscope (SPM) is connected to a gated CCD camera. CCD cameras can enhance the optical signal by about 10 4 The threshold time may vary from 5ns to 1 s. The output of a Photomultiplier (PM) is input into an oscilloscope, the photomultiplier is a side window type, and the spectral sensitivity is 300-800 nm. In the observation of photomultipliers, blue and red filters were used to measure corona and dry-charged arc discharge. The spectrum of the dry charged discharge was observed with a Na filter.
Step one: experimental conditions were set, the flow rate of the salt fog was 0.9l/h, and the water conductivity was 800. Mu.S/cm. The applied voltage was 15kV, the frequency was 60Hz, and the average electric field was 60V/mm. One aging period includes two operations of a salt spray aging period of 8 hours and a drying period of 16 hours, and then a total aging test time of 500 hours is set, and a leakage current is measured every 15 minutes.
Step two: the separation of the corona discharge component from the leakage current is achieved using a Fast Fourier Transform (FFT). According to FFT analysis, the frequency range of corona discharge is above 5kHz, while the frequency range of conductive arc discharge current and dry-charged arc discharge current is below 2 kHz. Then, a current component of 2.5kHz or more is defined as a current component generated by corona discharge.
Step three: fig. 1 shows a flow chart of the separation procedure. Leakage current data is first read, and then the total charge Qt is calculated and FFT analysis is performed. And separating corona discharge components above 2.5kHz by a digital high-pass filter to obtain corona discharge charges Qp and Qa. Differential techniques are used to determine whether each current component is caused by a dry-charged arc discharge. In the case where the current component does not include dry-charge discharge, the conduction current is calculated. In the case where the current component includes a dry-charged arc discharge, the electric charge Qd and the conductive electric charge Qc are obtained. Finally, each accumulated charge is calculated. The above calculation process is automatically repeated until the aging test is finished.
Step four: during the salt spray test and after the end of the test, the light emission of the discharge phenomenon was observed using a still camera.
Step five: after 500h of salt spray aging, the photoelectron spectrum of the silicon was analyzed by ESCA.
Step six: the observed spectrum was divided into 4 spectral components, si (-O) respectively 1， Si(-O) 2 ,Si(-O) 3 And Si (-O) 4 . Main component Si (-O) of silicone rubber 2 Reduced radicals, while Si (-O) 3 And Si (-O) 4 The number of groups increases. Namely PDMS (polydimethylsiloxane, si (-O) 2 ) Becomes Si (-O) 3 And Si (-O) 4 . SiO in HTV sample 3 And SiO 4 The component proportions of (a) are about 23% and 17%, respectively.
Whereas in RTV samples SiO 3 Reduction of SiO 4 And (3) increasing. These SiO' s 3 To SiO 4 The composition changes are caused by corona discharge between water droplets or dry-charged arc discharge of sample surface heating in salt spray aging tests. The change in composition also indicates that the bond between Si and CH is broken. Relates to Si (-O) 4 Without methyl groups (CH) 3 ) Only double bonds are formed with O, which promotes lower hydrophobicity and forms a water film on the surface. As described above, RTV has lower insulating properties than HTV. Thus, the more severe the ageing conditions, the more Si (-O) is formed 4 The more groups. Thus, an increase in surface contamination of the material results in a decrease in hydrophobicity, thereby promoting the occurrence of corona discharge. Corona discharge further reduces the hydrophobic properties and increases leakage current. The increase in leakage current promotes the occurrence of dry-charge discharge, and promotes surface deterioration.
Leakage currents including dry-charged discharge can be clearly separated by the differential technique we propose. The conductive charge, dry-band arc and corona charge account for about 70%, 20% and 10% of the total accumulated charge, respectively. And it is known by examples that HTV silicone rubber added with ATH can better maintain its insulating properties compared to RTV.
It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.
Furthermore, it should be understood that although the present disclosure describes embodiments, not every embodiment is provided with a separate embodiment, and that this description is provided for clarity only, and that the disclosure is not limited to the embodiments described in detail below, and that the embodiments described in the examples may be combined as appropriate to form other embodiments that will be apparent to those skilled in the art.
Claims (6)
1. The utility model provides a composite insulator surface insulating properties evaluation method based on novel leakage current separation technique which characterized in that, novel leakage current separation technique includes:
leakage current, the monitoring leakage current has the advantage of online evaluation; the leakage current provides information on the pollution degree of the polluted insulator, and focuses on the relation between discharge light emission and leakage current obtained in a salt spray aging test; observing light emission caused by two discharges by using a spectroscope, a photomultiplier and a still camera, and then evaluating the characteristics of the light emission and comparing the characteristics with leakage current;
separation technology, wherein the separation of corona discharge components and leakage current is carried out by Fast Fourier Transform (FFT); based on experimentally defined discharge types, the leakage current is divided into three components, such as a conductive current flowing in a water film on the surface of the composite insulator, a corona discharge current and a dry-charged arc discharge current; finally, carrying out chemical analysis (ESCA) on the surface of the composite insulator by utilizing an electron spectroscopy; then evaluating the change of the composite insulator component;
the method for evaluating the surface insulation performance of the composite insulator comprises the following steps:
1) In the salt spray aging test, salt spray aging test at 1.1.1 3 Is carried out in an acrylic acid chamber; two kinds of silicone rubber different in shape were used as insulator samples;
2) Separating the corona discharge component from the leakage current using a Fast Fourier Transform (FFT); according to FFT analysis, the frequency range of corona discharge is above 5khz, and the frequency ranges of conductive arc discharge current and dry-charged arc discharge current are below 2 khz; then, a current component above 2.5kHz is defined as a current component generated by corona discharge;
3) The initiation of the dry-charged arc discharge is determined by differential techniques, wherein a large rate of change of leakage current is used as an indicator; in addition, we assume that the conduction current is the difference between the leakage current and the corona discharge current plus the dry-charged arc discharge current;
4) Observing light emission of discharge phenomenon by using a still camera during and after the salt spray test; in order to measure the spectral distribution of the discharge emission, a Spectroscope (SPM) is connected with a gating CCD camera; inputting the output of the Photomultiplier (PM) into an oscilloscope and analyzing on a personal computer; in the observation of photomultipliers, blue and red filters were used to measure corona and dry-charged arc discharge; the spectrum of the dry charged discharge was observed with a Na filter;
5) Through a salt spray aging test, analyzing the photoelectron spectrum of Si by using ESCA; the photoelectron spectra of Si of the original RTV, exposed RTV and exposed HTV were observed.
2. The composite insulator surface insulation performance evaluation method based on the novel leakage current separation technology as claimed in claim 1, wherein the method comprises the following steps: the separation of the corona discharge component and the leakage current is firstly carried out by Fast Fourier Transform (FFT); the insulating property evaluation method is to use an electron spectroscopy to carry out chemical analysis on the surface of the composite insulator.
3. According to claim 2The method for evaluating the surface insulation performance of the composite insulator based on the novel leakage current separation technology is characterized by comprising the following steps of: in the step 1), two kinds of silicon rubber with different shapes are used, wherein one of the two kinds of silicon rubber is rod-shaped silicon rubber with the diameter of 30mm and the length of 250 mm; the other is a plate-shaped silicon rubber with the thickness of 2mm, and the cross section area of the plate-shaped silicon rubber is 80mm 2 The method comprises the steps of carrying out a first treatment on the surface of the In addition, two kinds of rubber different in rod rubber and filler are used; one of them is high temperature vulcanized silicone rubber (HTV) with Alumina Trihydrate (ATH) and SiO as fillers; the ATH content was 50%; the other is room temperature vulcanized silicone Rubber (RTV), and the filler is SiO only; siO in silicone rubber acts to enhance performance, and Alumina Trihydrate (ATH) provides tracking and erosion resistance; the plate-shaped sample uses high temperature vulcanized silicone rubber (HTV).
4. The composite insulator surface insulation performance evaluation method based on the novel leakage current separation technology as claimed in claim 3, wherein the method comprises the following steps: dividing leakage current into three components of conducting current, dry-charged arc discharge current and corona discharge current; calculating respective accumulated charges from the current components; in addition, chemical analysis (ESCA) of the composite insulator surface was performed using electron spectroscopy; the bonding conditions are then evaluated.
5. The composite insulator surface insulation performance evaluation method based on the novel leakage current separation technology as claimed in claim 1, wherein the method comprises the following steps: in the step 4), the leakage current consists of a sine wave with the frequency of 60hz and a plurality of pulse components with the main pulse width of tens of ns and ms, and for the current pulse with the pulse width of a few ms, the leakage current rapidly increases; the current pulse with longer pulse width is the dry-charged arc discharge bridged over longer distance; the short time current pulse is a locally distributed corona discharge, wherein the total amount of charge generated by the corona discharge is less than the total amount of charge generated by a dry charged arc discharge.
6. The composite insulator surface insulation performance evaluation method based on the novel leakage current separation technology as claimed in claim 1, wherein the method comprises the following steps: in the step 1), in the salt spray aging test, two discharge phenomena can be generally observed to evaluate the insulation performance of the material; one of them is a corona (partial) discharge occurring between water droplets, in which Si-C bonds of the silicone rubber are broken by photon energy, since the photon energy generated by the corona discharge is greater than the energy of the Si-C bonds; thus, the insulation surface condition can be defined by the corona discharge activity on the hydrophobic surface; the other is dry charge discharge which occurs between dry bands on the surface of the high polymer material; the half width of the dry-charged arc discharge current is about 15ms, which may cause tracking and erosion phenomena, the accumulated charge of which is much greater than that of corona discharge.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311543341.9A CN117452165A (en) | 2023-11-17 | 2023-11-17 | Composite insulator surface insulation performance evaluation method based on novel leakage current separation technology |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311543341.9A CN117452165A (en) | 2023-11-17 | 2023-11-17 | Composite insulator surface insulation performance evaluation method based on novel leakage current separation technology |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117452165A true CN117452165A (en) | 2024-01-26 |
Family
ID=89587414
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311543341.9A Pending CN117452165A (en) | 2023-11-17 | 2023-11-17 | Composite insulator surface insulation performance evaluation method based on novel leakage current separation technology |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117452165A (en) |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11312422A (en) * | 1998-04-28 | 1999-11-09 | Central Res Inst Of Electric Power Ind | Judging method for dirt conditions of high-tension insulator and high-tension insulator dirt monitor system using same |
| JP2002328147A (en) * | 2001-04-27 | 2002-11-15 | Kyushu Inst Of Technology | Automatic measuring instrument for separation- measuring three components of frequency in leak current for polymer insulator |
| JP2003270288A (en) * | 2002-03-14 | 2003-09-25 | Kyushu Electric Power Co Inc | Method and apparatus for separating and analyzing leakage current component |
| CN206696385U (en) * | 2017-05-08 | 2017-12-01 | 三峡大学 | A kind of silastic material surface state man-made chamber platform |
| CN108195866A (en) * | 2018-01-08 | 2018-06-22 | 国网河北省电力有限公司电力科学研究院 | A kind of determination method of composite insulator silicon rubber degree of aging |
| CN111965097A (en) * | 2020-09-29 | 2020-11-20 | 海南电网有限责任公司电力科学研究院 | Method for evaluating anti-aging performance of new composite insulator in tropical environment |
| CN115453296A (en) * | 2022-10-10 | 2022-12-09 | 国网山东省电力公司电力科学研究院 | Method and system for analyzing insulation degradation of epoxy resin insulator and diagnosing faults of epoxy resin insulator |
| CN115753863A (en) * | 2022-09-23 | 2023-03-07 | 国网新疆电力有限公司电力科学研究院 | Method for identifying surface aging degree of composite silicone rubber insulator |
| CN115980623A (en) * | 2022-12-13 | 2023-04-18 | 广东电网有限责任公司 | Performance test method of polluted composite insulator |
-
2023
- 2023-11-17 CN CN202311543341.9A patent/CN117452165A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11312422A (en) * | 1998-04-28 | 1999-11-09 | Central Res Inst Of Electric Power Ind | Judging method for dirt conditions of high-tension insulator and high-tension insulator dirt monitor system using same |
| JP2002328147A (en) * | 2001-04-27 | 2002-11-15 | Kyushu Inst Of Technology | Automatic measuring instrument for separation- measuring three components of frequency in leak current for polymer insulator |
| JP2003270288A (en) * | 2002-03-14 | 2003-09-25 | Kyushu Electric Power Co Inc | Method and apparatus for separating and analyzing leakage current component |
| CN206696385U (en) * | 2017-05-08 | 2017-12-01 | 三峡大学 | A kind of silastic material surface state man-made chamber platform |
| CN108195866A (en) * | 2018-01-08 | 2018-06-22 | 国网河北省电力有限公司电力科学研究院 | A kind of determination method of composite insulator silicon rubber degree of aging |
| CN111965097A (en) * | 2020-09-29 | 2020-11-20 | 海南电网有限责任公司电力科学研究院 | Method for evaluating anti-aging performance of new composite insulator in tropical environment |
| CN115753863A (en) * | 2022-09-23 | 2023-03-07 | 国网新疆电力有限公司电力科学研究院 | Method for identifying surface aging degree of composite silicone rubber insulator |
| CN115453296A (en) * | 2022-10-10 | 2022-12-09 | 国网山东省电力公司电力科学研究院 | Method and system for analyzing insulation degradation of epoxy resin insulator and diagnosing faults of epoxy resin insulator |
| CN115980623A (en) * | 2022-12-13 | 2023-04-18 | 广东电网有限责任公司 | Performance test method of polluted composite insulator |
Non-Patent Citations (1)
| Title |
|---|
| 张冠军;赵林;周润东;申文伟;梁曦东: "硅橡胶复合绝缘子老化表征评估研究的现状与进展", 高压电器, vol. 52, no. 04, 16 April 2016 (2016-04-16), pages 1 - 15 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Ahmadi-Joneidi et al. | Aging evaluation of silicone rubber insulators using leakage current and flashover voltage analysis | |
| Sundararajan et al. | Dynamic arc modeling of pollution flashover of insulators under dc voltage | |
| Zhao et al. | Flashover voltage prediction of composite insulators based on the characteristics of leakage current | |
| Zhijin et al. | Characterization of silicone rubber degradation under salt-fog environment with AC test voltage | |
| Otsubo et al. | Evaluation of insulation performance of polymeric surface using a novel separation technique of leakage current | |
| Mavrikakis et al. | Laboratory investigation on hydrophobicity and tracking performance of field aged composite insulators | |
| Samakosh et al. | Analysis of leakage current characteristics during aging process of SiR insulator under uniform and longitudinal non-uniform pollution conditions | |
| CN111610249B (en) | Method for evaluating aging state of high-temperature vulcanized silicone rubber | |
| Maraaba et al. | Performance evaluation of 230 kV polymer insulators in the coastal area of Saudi Arabia | |
| Saldivar-Guerrero et al. | Application of unusual techniques for characterizing ageing on polymeric electrical insulation | |
| CN117452165A (en) | Composite insulator surface insulation performance evaluation method based on novel leakage current separation technology | |
| da Silva et al. | Analysis of electrical tracking by energy absorption during surface discharge in polymeric materials | |
| Kim et al. | Effects of saline-water flow rate and air speed on leakage current in RTV coatings | |
| Jahromi et al. | Prediction of leakage current of composite insulators in salt fog test using neural network | |
| Sarathi et al. | Investigations into the surface condition of silicone rubber insulation material using multiresolution signal decomposition | |
| Zhu et al. | Influence of moist environment on aging performance of energized silicone rubber used for outdoor insulation | |
| Prakash et al. | Mathematical modeling on AC pollution flashover performance of glass and composite insulator | |
| Arief et al. | Estimated leakage current based on the thermal image of the polymer insulator using the color detection method | |
| Esmaieli et al. | Condition assessment criteria evaluation of asymmetric aged and fully aged silicone rubber insulators based on leakage current harmonics | |
| Zhou et al. | The relationship between microstructure and hydrophobicity of service-aged silicone rubber insulators | |
| Peng et al. | Hydrophobicity and surface microstructure changing regulations of HTV silicone rubber under corona accelerated aging | |
| Thong-Om et al. | Comparison Ageing Deterioration of Silicone Rubber Outdoor Polymer Insulators in Artificial Accelerated Salt Fog Ageing Test | |
| Khaing et al. | Evaluation of degradation degree of artificially degraded silicone rubber surface by using surface discharge | |
| Mafasigodo | Using inclined plane test to compare tracking on silicon rubber under HVAC and HVDC. | |
| Ashitha et al. | A study on the effect of UV radiations on silicone rubber insulators under polluted conditions using inclined plane tracking and erosion test |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |