CN105136550A - Method of checking harmful impurities in copper conductor for transformer - Google Patents
Method of checking harmful impurities in copper conductor for transformer Download PDFInfo
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- CN105136550A CN105136550A CN201510578449.0A CN201510578449A CN105136550A CN 105136550 A CN105136550 A CN 105136550A CN 201510578449 A CN201510578449 A CN 201510578449A CN 105136550 A CN105136550 A CN 105136550A
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Abstract
The invention provides a method of checking harmful impurities in a copper conductor for a transformer. The method comprises the following steps: 1. cutting the copper conductor into a plurality of samples with uniform shapes by using linear cutting equipment; tightly covering the samples with insulating paper and putting the samples into a vacuum box, and keeping for 12-48 hours; 2. adding benzyl disulfide into insulating oil and sealing under a sealed environment which is fully filled with nitrogen gas; 3. sampling and measuring; 4. detecting a surface microscopic appearance of the copper conductor, and the variety and content of elements in a corrosion pit by using a scanning electron microscope/energy spectrum, and observing the size of the corrosion pit and the condition of the impurities. According to the checking method provided by the invention, conditions including oxygen concentration, the position of the copper conductor and the like are controlled through adjusting the vacuum degree of an ageing environment, and rapid thermal aging is carried out on the copper conductor. By utilizing the scanning electron microscope/energy spectrum to detect the surface microscopic appearance of the copper conductor and the composition conditions of the elements in the corrosion pit, whether the harmful impurities exist in the copper conductor for the transformer is detected, and support of experimental data is provided for the prevention and treatment of an oil sulfur corrosion phenomenon of the transformer.
Description
Technical field
The invention belongs to electrical engineering and material science and intersect category, specifically, by controlling oxygen, DBDS concentration, the copper conductor condition such as riding position in the environment, to the acceleration heat ageing that copper conductor carries out in various degree, the recycling aging rear copper conductor microscopic appearance of scanning electron microscope/power spectrum research and the life of etch pit interior element contamination, judge a kind of method of inspection of objectionable impurities in copper conductor.
Background technology
Transformer is the core of energy conversion in delivery of electrical energy and delivery process, is most important in electric power netting safe running and one of the equipment of most critical.The major accident of transformer not only can cause the damage of self, also can interrupt electric power supply, causes huge economic loss to society.Nearly ten years, the area power grids such as Fujian, Shenzhen, east and North China find that fault winding and coated insulating paper top layer all find that there is dark blue and light gray solid sediment in succession in the transformer fault inspection of 220kV and 500kV, confirm that the principal ingredient of this material is cuprous sulfide precipitation by analysis.Similar phenomenon also result in attention abroad, A2-32 working group is organized to end the incomplete statistics of 2009 according to international bulk power grid, because sulfur corrosion problem causes or doubtful high-power transformer fault about 100 example from 2000, relate to multiple main transformer production business, its insulating oil used is provided by the insulating oil supplier of multiple international top-brand.These accidents occur on voltage levels, Large Copacity, high oil temperature, large load, the transformer being with sealing conservator and reactor mostly; Cuprous sulfide deposition site concentrates on the direct winding contacted with insulating paper of bare copper wire, and mainly occurs in the first half of high pressure winding, is associated with trouble location.Although sulfur corrosion problem was just caused attention in nearly ten years, the testing result again of the winding of historical failure transformer is also demonstrated to the existence of this phenomenon.Along with the raising be familiar with this phenomenon, the exposure of problems equipment also shows a rising trend.Thus, the coil of converting equipment and paper oil insulation material suffer problem that corrosivity sulfur product corrodes to cause the concern of more and more international correlation engineering technician and researcher.
In recent years, the hazard mechanism of oily sulfur corrosion problem to the equipment such as transformer, reactor obtains Preliminary study.The harm, source, coherent detection standard, braking measure etc. of mordant-active sulfur in mineral insulating oil are all studied.But also little for the research of the material-copper conductor be corroded in transformer in Oil-Paper Insulation, and transformer special purpose copper is a kind of high purity copper-red copper, itself contains plurality of impurities, but content is lower.Table 1 is dopant species and content in red copper.According to movable metallic sequence list 2, the activity of partial impurities is far away higher than copper, and under same corrosion environment, this impurity is more tending towards corroding prior to copper in theory, and formed sulfur product be deposited on insulating paper or dispersion suspension in insulating oil; The activity of same partial impurities, lower than copper, under same corrosion environment, forms primary element with copper, copper corrosion is accelerated, in Oil-Paper Insulation, forms cuprous sulfide, thus initiating failure.
Dopant species and content in table 1 red copper
Table 2 movable metallic sequence list
| Movable metallic order | K>Ca>Na>Mg>Al>Zn>Fe>Sn>Pb>H>Cu>Hg>Ag>Pt>Au |
Comparatively generally acknowledge in the world at present method be also add passivator in transformer oil, passivator is benzotriazole (BTA) and derivant thereof.The heteroatomss such as N, O, S in BTA and derivative molecular thereof contain lone pair electrons; be easy to combine with the d track of metal form coordination bond; or metal carrying supplied for electronic forms back coordination key to heteroatoms; thus form diaphragm in metal surface, stop the oxidation of Transformer Winding coil and the contact with active sulfur in oil.But passivator can constantly consume in time.And when local overheating or shelf depreciation, inactive sulfur can change to active sulphur.The carrying out of some harmful middle impurity meeting accelerated corrosion can be there is in copper conductor simultaneously.What this illustrated passivator adds the generation can taking precautions against active sulfur problem to a certain extent, but the problem of copper sulfur corrosion still exists.Select suitable method, detect dopant species in copper conductor and oily sulfur corrosion degree is carried out to transformer, and effective risk assessment is carried out to transformer and running status assessment is significant.
Summary of the invention
Technical matters: technical matters to be solved by this invention is: a kind of element kind by utilizing in the aging rear micro-raman spectra of scanning electron microscope/power spectrum research copper conductor in etch pit being provided, judging the method for inspection whether copper conductor objectionable impurities exists.
Technical scheme: for solving the problems of the technologies described above, the technical solution used in the present invention is:
Check a method for objectionable impurities in transformer copper conductor, this method of inspection comprises the following steps:
Copper conductor utilizes Linear cut to cut equipment and is slit into the uniform sample of some shapes by step 1., closely superscribe insulating paper, be placed in vacuum tank, dry 12-72 hour at 60-120 DEG C, after be cooled to room temperature-40 DEG C, immerse the degassed new transformer oil (not containing active sulfur compound, total sulfur content≤1000ppm) that dewaters and keep 12-48 hour;
Step 2. adds benzyl disulfide (DBDS) in insulating oil, and concentration is 10-10000ppm, and by oil (quality g): (surface area cm
2) ratio scope be 1-50, insulating oil is added in conical flask, copper winding sample after immersion oil is loaded in conical flask simultaneously, at the bottom of keeping copper bar to lie in bottle, after conical flask is placed in vacuum nitrogen case, vacuumize and under vacuum state, fill nitrogen to one standard atmospheric pressure, after seal under environment that is airtight, that be full of nitrogen;
Step 3. is by above-mentioned copper conductor sample as in 80 DEG C-240 DEG C vacuum ageing ovens, and control vacuum tightness 0.01-1MPa and carry out thermal aging test, thermal aging time is 10-1000 hour, and sampling is measured;
Step 4. utilizes scanning electron microscope/power spectrum to detect copper conductor surface microscopic topographic and etch pit interior element kind and content, observes etch pit size and impurity situation.
Utilized by copper conductor Linear cut to cut equipment in step 1 of the present invention and be slit into the uniform sample of some shapes, closely superscribe insulating paper, to produce heat ageing product, accelerate the corrosion of copper conductor;
The DBDS added in insulating oil in step 2 of the present invention, concentration is 10-10000ppm (DBDS is active sulfur).
In step 2 of the present invention, copper conductor sample after immersion oil is loaded in conical flask, at the bottom of keeping copper bar to lie in bottle, to accelerate copper conductor corrosion;
In step 3 of the present invention, in vacuum ageing oven, environment temperature controls within the scope of 80-240 DEG C;
Control vacuum tightness 0.01-1MPa in step 3 of the present invention and carry out thermal aging test, to accelerate the corrosion of copper conductor;
In step 4 of the present invention, adopt scanning electron microscope/power spectrum to detect copper conductor surface microscopic topographic, detect the situations such as etch pit interior element contamination, namely judge the impurity causing copper conductor accelerated corrosion in copper conductor, i.e. objectionable impurities kind;
The invention has the beneficial effects as follows: there is no at present, by observing the aging rear microscopic appearance of copper conductor and etch pit interior element situation, the method that in inspection transformer copper wire, whether objectionable impurities exists.The present invention has following beneficial effect:
The method of inspection of the present invention considers oily sulfur corrosion phenomenon in power equipment, by regulating the conditions such as ageing environment vacuum degree control oxygen concentration, copper conductor position, carries out acceleration heat ageing to copper conductor.By utilizing scanning electron microscope/power spectrum to copper conductor surface microscopic topographic and etch pit interior element composition situation, in inspection transformer copper conductor, whether objectionable impurities exists, and is the support providing experimental data of the control of transformer oil sulfur corrosion phenomenon.
Accompanying drawing explanation
Fig. 1, Fig. 2 are microscopic appearance and the etch pit element composition of aging rear copper conductor sample surfaces in 200ppmDBDS insulating oil in example 1 step 4 of the present invention;
Fig. 3, Fig. 4 are at the microscopic appearance of 500ppmDBDS aging rear copper conductor sample surfaces in insulating oil and etch pit element composition in example 2 step 4 of the present invention.
Embodiment
Below in conjunction with accompanying drawing and embodiment, technical scheme of the present invention is described in detail.
Example 1:
A kind of method checking objectionable impurities in transformer copper conductor of the present invention, comprises the following steps:
Copper conductor utilizes Linear cut to cut equipment and is slit into the uniform sample of some shapes by step 1., closely superscribes insulating paper, is placed in vacuum tank, at 90 DEG C dry 48 hours, after be cooled to 40 DEG C, immerse the degassed new transformer oil that dewaters and keep 12 hours;
Step 2. adds DBDS in insulating oil, and concentration is 200ppm, and presses 1g oil: 0.5cm
2the ratio of copper adds insulating oil in conical flask, copper conductor sample after immersion oil is loaded in conical flask simultaneously, at the bottom of keeping copper bar to lie in bottle, and immerse insulating oil, after conical flask is placed in vacuum nitrogen case, vacuumize and under vacuum state, fill nitrogen to one standard atmospheric pressure, after seal under environment that is airtight, that be full of nitrogen;
Step 3. is by above-mentioned copper conductor sample as in 150 DEG C of vacuum ageing ovens, and control vacuum tightness 0.01 and carry out thermal aging test, thermal aging time is 72 hours, and sampling is measured; Fig. 1 is the situation of aging rear copper conductor sample in case step 3 of the present invention, and can find out from figure, there is obvious corrosion phenomenon on copper conductor surface.
Step 4. utilizes scanning electron microscope/power spectrum to detect copper conductor surface microscopic topographic and etch pit interior element kind and content, observes etch pit size and etch pit interior element composition situation; Fig. 2 observes aging rear copper conductor sample microscopic appearance and etch pit interior element composition by scanning electron microscope/power spectrum in case step 4 of the present invention.Can obtain copper conductor surface by figure has etch pit to exist, and to obtain hole interior element by power spectrum be Cu, Al, and etch pit diameter is larger, and the interior aluminium element content in hole is more, and obtaining copper conductor harmful element is thus aluminium element.
Utilized by copper conductor Linear cut to cut equipment in step 1 of the present invention and be slit into the uniform sample of some shapes, closely superscribe insulating paper, to produce the corrosion that heat ageing product accelerates copper conductor;
The DBDS added in insulating oil in step 2 of the present invention, concentration is 200ppm.
In step 2 of the present invention, copper conductor sample after immersion oil is loaded in conical flask, at the bottom of keeping copper bar to lie in bottle, to accelerate copper conductor corrosion;
In step 3 of the present invention in 80 DEG C-150 DEG C vacuum ageing ovens, be because accelerated corrosion must occur higher than 80 DEG C of ability;
Controlling vacuum tightness 0.01-0.9 in step 3 of the present invention and carry out thermal aging test, is because the existence of oxygen can accelerate the corrosion of copper conductor;
In step 4 of the present invention, adopt scanning electron microscope to detect copper conductor surface microscopic topographic, detect the situations such as etch pit interior element contamination, namely judge the impurity causing copper conductor accelerated corrosion in copper conductor, i.e. objectionable impurities kind.
Example 2:
A kind of method checking objectionable impurities in transformer copper conductor of the present invention, comprises the following steps:
Copper conductor utilizes Linear cut to cut equipment and is slit into the uniform sample of some shapes by step 1., closely superscribes insulating paper, is placed in vacuum tank, at 90 DEG C dry 48 hours, after be cooled to 40 DEG C, immerse the degassed new transformer oil that dewaters and keep 12 hours;
Step 2. adds DBDS in insulating oil, and concentration is 500ppm, and presses 1g oil: 0.5cm
2the ratio of copper adds insulating oil in conical flask, copper conductor sample after immersion oil is loaded in conical flask simultaneously, at the bottom of keeping copper bar to lie in bottle, and immerse insulating oil, after conical flask is placed in vacuum nitrogen case, vacuumize and under vacuum state, fill nitrogen to one standard atmospheric pressure, after seal under environment that is airtight, that be full of nitrogen;
Step 3. is by above-mentioned copper conductor sample as in 145 DEG C of vacuum ageing ovens, and control vacuum tightness 0.1 and carry out thermal aging test, thermal aging time is 96 hours, and sampling is measured; Fig. 3 is the situation of aging rear copper conductor sample in case step 3 of the present invention, and can find out from figure, there is obvious corrosion phenomenon on copper conductor surface.
Step 4. utilizes scanning electron microscope/power spectrum to detect copper conductor surface microscopic topographic and etch pit interior element kind and content, observes etch pit size and etch pit interior element composition situation; Fig. 4 observes aging rear copper conductor sample microscopic appearance and etch pit interior element composition by scanning electron microscope/power spectrum in case step 4 of the present invention.Can obtain copper conductor surface by figure has etch pit to exist, and to obtain hole interior element by power spectrum be Cu, Si, and etch pit diameter is larger, and the interior silicon content in hole is more, and obtaining copper conductor harmful element is thus element silicon.
Claims (3)
1. check a method for objectionable impurities in transformer copper conductor, it is characterized in that, this measuring method comprises the following steps:
Copper conductor utilizes Linear cut to cut equipment and is slit into the uniform sample of some shapes by step 1., closely superscribe insulating paper, be placed in vacuum tank, dry 12-72 hour at 60-120 DEG C, after be cooled to room temperature-40 DEG C, immerse degassed dewater not containing active sulfur compound, the new transformer oil of total sulfur content≤1000ppm, and keep 12-48 hour;
Step 2. adds benzyl disulfide DBDS in insulating oil, and concentration is 10-10000ppm, and by quality g: the surface area cm of oil
2ratio scope be 1-50, insulating oil is added in conical flask, copper winding sample after immersion oil is loaded in conical flask simultaneously, at the bottom of keeping copper bar to lie in bottle, after conical flask is placed in vacuum nitrogen case, vacuumize and under vacuum state, fill nitrogen to one standard atmospheric pressure, after seal under environment that is airtight, that be full of nitrogen;
Step 3. is by above-mentioned copper conductor sample as in 80 DEG C-240 DEG C vacuum ageing ovens, and control vacuum tightness 0.01-1MPa and carry out thermal aging test, thermal aging time is 10-1000 hour, and sampling is measured;
Step 4. utilizes scanning electron microscope/power spectrum to detect copper conductor surface microscopic topographic and etch pit interior element kind and content, observes etch pit size and impurity situation.
2. a kind of method checking objectionable impurities in transformer copper conductor as claimed in claim 1, it is characterized in that, utilized by copper conductor Linear cut to cut equipment in described step 1 and be slit into the uniform sample of some shapes, closely superscribe insulating paper, to produce heat ageing product, accelerate the corrosion of copper conductor.
3. a kind of method checking objectionable impurities in transformer copper conductor as claimed in claim 1, is characterized in that, the DBDS added in insulating oil in described step 2, and concentration is 10-10000ppm.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106198588A (en) * | 2016-08-17 | 2016-12-07 | 云南电网有限责任公司电力科学研究院 | The detection method of objectionable impurities in a kind of transformator copper conductor |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104076232A (en) * | 2014-07-17 | 2014-10-01 | 国网上海市电力公司 | Transformer oil-paper insulation electricity-heating unite ageing test device |
| CN104792691A (en) * | 2015-04-22 | 2015-07-22 | 西安交通大学 | Testing method for researching influence of temperature, electric field and gases on copper corrosion process |
-
2015
- 2015-09-11 CN CN201510578449.0A patent/CN105136550A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104076232A (en) * | 2014-07-17 | 2014-10-01 | 国网上海市电力公司 | Transformer oil-paper insulation electricity-heating unite ageing test device |
| CN104792691A (en) * | 2015-04-22 | 2015-07-22 | 西安交通大学 | Testing method for researching influence of temperature, electric field and gases on copper corrosion process |
Non-Patent Citations (7)
| Title |
|---|
| 任双赞等: "变压器油中腐蚀性硫对铜导线及油浸绝缘纸特性影响", 《电工技术学报》 * |
| 徐积全: "腐蚀性硫化物沉积对变压器油纸绝缘特性的影响研究", 《中国优秀硕士论文全文数据库 工程科技II辑》 * |
| 李久青等编著: "《腐蚀试验方法及监测技术》", 31 May 2007 * |
| 李健美等: "受腐蚀钢筋混凝土构件腐蚀机理实验研究", 《建筑结构》 * |
| 王明娥等: "液氨球罐应力腐蚀开裂的诊断", 《化工学报》 * |
| 赵健明等: "45Mn2 钢管的"亮线"缺陷分析", 《理化检验-物理分析》 * |
| 赵维敏: "铜导线一次短路熔珠内表面元素分布规律研究", 《消防科学与技术 》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106198588A (en) * | 2016-08-17 | 2016-12-07 | 云南电网有限责任公司电力科学研究院 | The detection method of objectionable impurities in a kind of transformator copper conductor |
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