CN105699417A - Characterization method for corrosive sulfur of transformer insulating oil - Google Patents
Characterization method for corrosive sulfur of transformer insulating oil Download PDFInfo
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- CN105699417A CN105699417A CN201610047988.6A CN201610047988A CN105699417A CN 105699417 A CN105699417 A CN 105699417A CN 201610047988 A CN201610047988 A CN 201610047988A CN 105699417 A CN105699417 A CN 105699417A
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- transformer
- active sulfur
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- insulating oil
- transformer insulation
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N25/00—Investigating or analyzing materials by the use of thermal means
- G01N25/20—Investigating or analyzing materials by the use of thermal means by investigating the development of heat, i.e. calorimetry, e.g. by measuring specific heat, by measuring thermal conductivity
Abstract
The embodiment of the invention discloses a characterization method for corrosive sulfur of transformer insulating oil. The characterization method comprises the following steps: adding benzyl disulfide into the insulating oil, and immersing a copper lead wire sample immersed with new transformer oil into the insulating oil; then vacuumizing and sealing under a sealed environment which is fully filled with nitrogen gas; controlling vacuum degree, thermal ageing temperature and thermal ageing time of the copper lead wire sample subjected to the sealing treatment; carrying out a thermal ageing test in a vacuum ageing box; then sampling and testing; and characterizing a transformer insulating oil corrosive sulfur condition by testing an insulating paper thermal conductivity coefficient. The transformer insulating oil corrosive sulfur condition is characterized from qualitative and quantitative views, so that the transformer insulating oil corrosive sulfur condition can be characterized, and the characterization method can also have important meaning in effective risk evaluation and operation state evaluation of the operation of a transformer.
Description
Technical field
The present invention relates to the sign of transformer insulated oil corrosion, particularly relate to the characterizing method of active sulfur in transformer insulation oil, belong to transformator corrosion-resistant field。
Background technology
Transformator is the core of energy conversion in electric energy transmission and delivery process, is one of most important equipment with most critical in electric power netting safe running。The major accident of transformator not only can cause the damage of self, also can interrupt supply of electric power, cause huge economic loss to society。Nearly ten years, the transformer fault inspection of 220kV and 500kV finding, all there is dark blue and light gray solid deposit on the insulating paper top layer of fault winding and cladding, what confirm this material by analysis is mainly composed of cuprous sulfide precipitation, and similar phenomenon also result in attention abroad。According to the cut-off incomplete statistics of 2009 of international bulk power grid tissue A2-32 working group, from 2000 due to or doubtful sulfur corrosion problem cause high-power transformer fault about 100 example, relating to multiple main transformer production business, its insulating oil used is provided by the insulating oil supplier of multiple international top-brands。These accidents mostly occur in voltage levels, Large Copacity, high oil temperature, big load, with sealing on the transformator of conservator and reactor；Cuprous sulfide deposition site concentrates on the winding that bare copper wire directly contacts with insulating paper, and occurs mainly in the first half of high pressure winding, is associated with trouble location。Although sulfur corrosion problem is just caused attention in last decade, but the testing result again of the winding of historical failure transformator is also demonstrated the existence of this phenomenon。The coil of converting equipment and paper oil insulation material suffer the problem that corrosivity sulfur product corrodes to cause the concern of more and more international correlation engineering technical staff and researcher。
At present, China's transformer oil active sulfur detection method has petrochemical industry standard SH/T0304-1999 " electric insulating oil active sulfur test method(s) " and SH/T0804-2007 " electric insulating oil active sulfur test (silver strip test method) "。Abroad have ISO standards ISO5662-1997 " electric insulating oil active sulfur test method(s) ", American Society for Testing and Materials standard ASTMD1275-2006 " electric insulating oil active sulfur test method(s) ", DIN DIN51353-1985 " electric insulating oil active sulfur test (silver strip test method) " and IEC IEC62535-2008 " with or the test method that detects of unused insulating oil potential corrosion sulfur "。Wherein, China petrochemical industry standard SH/T0304-1999 " electric insulating oil active sulfur test method(s) " is adopting by equivalent international standard ISO5662-1997 " electric insulating oil active sulfur test method(s) " and formulates, SH/T0804-2007 " electric insulating oil active sulfur test silver strip test method " be amendment DIN DIN51353-1985 " inspection of insulating oil. the detection to active sulfur. silver is with inspection " formulate afterwards。At present, ASTMD1275B " electric insulating oil active sulfur algoscopy " method and IEC62535-2008 " iknsulating liquid--with crossing and the detection test method of potential corrosion sulfur in unworn insulating oil " method is converted into national standard and power department standard by CNPC's Kelamayi lubricating oil institute。
Petrochemical industry standard SH/T0304-1999 " electric insulating oil active sulfur test method(s) ", ISO standards ISO5662-1997 " electric insulating oil active sulfur test method(s) ", American Society for Testing and Materials standard ASTMD1275-2006 " electric insulating oil active sulfur test method(s) " these three method judges whether transformer oil is corrosive, by means of GB/T5096 " oil product copper strip test method ", copper corrosion Standard colour board in ASTMD130 " by the copper strip test method detection oil product test method to copper corrosion performance ", 1, 2, 3 grades is non-corrosiveness, 4 grades for being corrosive (now, test piece is obvious black, black gray expandable or dark brown, graphite color, pitch-dark color, or the peeling of any degree)。SH/T0804-2007 " electric insulating oil active sulfur test silver strip test method ", DIN51353-1985 " inspection of insulating oil. the detection to active sulfur. silver band inspection " both approaches regulation, when test silver strip do not occur substantially fading or with faint golden yellow time be non-corrosiveness, silver strip from bright Lycoperdon polymorphum Vitt or light brown become lead to black time for being corrosive。IEC62535 " iknsulating liquid--used and the detection test method of potential corrosion sulfur in unworn insulating oil " method regulation, flat type copper wire surface is dag, for there being corrosion when dark brown, black, other color is corrosion-free, when insulating paper has the metallic deposit things such as the overlapping color that is similar to lead, stannum, silver, pyrite, bronze-colored or blue and purple, then it is assumed that be have corrosion。When flat type copper wire or insulating paper, or both of which is observed thinks when having corrosion, should judge that test specimen is corrosive。When flat type copper wire and insulating paper is observed think corrosion-free time, it is judged that test specimen is non-corrosiveness。
The result of above-mentioned transformer oil active sulfur detection method of the prior art judges to be through color change, with reference to contrast, it does not have a kind of quantitative method carries out definite measurement。
Summary of the invention
In order to solve above-mentioned technical problem, the invention provides a kind of method characterizing transformer insulation oil sulfur corrosion degree by copper winding insulation paper heat conductivity after measuring corrosion, transformer insulation oil sulfur corrosion degree can not only be characterized, and the risk assessment and running status assessment to transformator effective operation is significant。
The characterizing method of a kind of transformer insulation oil active sulfur provided in the embodiment of the present invention, it comprises the steps:
(1) copper conductor is slit into the sample of uniform length, then with insulating paper by described sample tight, subsequently the sample that insulating paper wraps up is placed in the vacuum drying oven that baking temperature is 85 DEG C～95 DEG C, dry, drying time is 43～53 hours, being subsequently cooled to 38 DEG C～42 DEG C, the sample after using the new transformer oil that deoxidation gas dewaters to infiltrate described cooling subsequently, infiltrating time is 10～14 hours；
(2) according to 1g oil: 0.5cm2The ratio of copper adds insulating oil in conical flask, then in insulating oil, add benzyl disulfide (DBDS), copper conductor sample after new transformer oil infiltration in step (1) is put into conical flask simultaneously, and immerse insulating oil, subsequently conical flask is placed in vacuum nitrogen case, evacuation and under vacuum state nitrogen charging to a normal atmosphere, seal under airtight, to be full of nitrogen environment subsequently；
(3) by the copper conductor sample after encapsulation process in step (2) as, in vacuum ageing oven, controlling vacuum, thermal aging temperature and thermal aging time, carry out thermal aging test, sampling subsequently is tested；
(4) test insulating paper heat conductivity, characterizes transformer insulation oil active sulfur situation。
Preferably, the characterizing method of above-mentioned transformer insulation oil active sulfur, wherein, the baking temperature in described step (1) is 90 DEG C, and drying time is 48 hours。
Preferably, the characterizing method of above-mentioned transformer insulation oil active sulfur, wherein, in described step (1), infiltrating time is 12 hours。
Preferably, the characterizing method of above-mentioned transformer insulation oil active sulfur, wherein, in described step (2), the concentration of benzyl disulfide is 0ppm～1000ppm。
Preferably, the characterizing method of above-mentioned transformer insulation oil active sulfur, wherein, in described step (3), vacuum is 0.01～0.9。
Preferably, the characterizing method of above-mentioned transformer insulation oil active sulfur, wherein, in described step (3), the temperature of heat ageing is 80 DEG C～165 DEG C。
Preferably, the characterizing method of above-mentioned transformer insulation oil active sulfur, wherein, in described step (3), thermal aging time is 24～1000 hours。
Preferably, the characterizing method of above-mentioned transformer insulation oil active sulfur, wherein, in described step (4), test insulating paper heat conductivity is to adopt laser heat conducting instrument to measure insulating paper heat conductivity。
The laser method of shining is a kind of for measuring highly heat-conductive material and the technology of small size solid material。Due to this technology there is precision height, the advantage such as sample used is little, test period is short, temperature range width and be widely studied and apply。The laser method that shines directly measures the thermal diffusivity of material, and thus draws its heat conductivity。
Compared with prior art, technical scheme is by adopting test insulating paper heat conductivity, characterize transformer insulation oil active sulfur situation, characterize transformer insulation oil active sulfur situation from qualitative and quantitative angle simultaneously, not only can characterize transformer insulation oil active sulfur situation, additionally it is possible to risk assessment and running status assessment to transformator effective operation are significant。
Accompanying drawing explanation
In order to be illustrated more clearly that the embodiment of the present invention or technical scheme of the prior art, the accompanying drawing used required in embodiment will be briefly described below, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skill in the art, under the premise not paying creative work, it is also possible to obtain other accompanying drawing according to these accompanying drawings。
Fig. 1. in the embodiment of the present invention 1～4 laser shine method test insulating paper Determination of conductive coefficients schematic diagram；
Fig. 2. the heat conductivity of insulating paper under different benzyl disulfide (DBDS) concentration in embodiment 1～4。
Detailed description of the invention
Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is carried out clear, complete description, it is clear that described embodiment is only a part of embodiment of the present invention, rather than whole embodiments。Based on the embodiment in the present invention, the every other embodiment that those of ordinary skill in the art obtain under not making creative work premise, broadly fall into the scope of protection of the invention。
Embodiment 1
The present embodiment material requested is as follows: the specification of copper winding is 60mm × 8.5mm × 3.5mm (length × width x thickness), and conical flask is 500ml band plug ground, can be high temperature resistant, benzyl disulfide (DBDS), molecular formula C14H14S2, molecular weight: 246.38。
The present embodiment provides the characterizing method of a kind of transformer insulation oil active sulfur, specifically includes following steps:
(1) copper conductor is slit into the sample of uniform length, then with insulating paper by described sample tight, subsequently the sample that insulating paper wraps up is placed in the vacuum drying oven that baking temperature is 90 DEG C, dry, drying time is 48 hours, being subsequently cooled to 40 DEG C, the sample after using the new transformer oil that deoxidation gas dewaters to infiltrate described cooling subsequently, infiltrating time is 12 hours；
(2) according to 1g oil: 0.5cm2The ratio of copper adds insulating oil in conical flask, then adding concentration in insulating oil is 200ppm benzyl disulfide (DBDS), copper conductor sample after new transformer oil infiltration in step (1) is put into conical flask simultaneously, and immerse insulating oil, subsequently conical flask is placed in vacuum nitrogen case, evacuation and under vacuum state nitrogen charging to a normal atmosphere, seal under airtight, to be full of nitrogen environment subsequently；
(3) by the copper conductor sample after encapsulation process in step (2) as in vacuum ageing oven, control vacuum be 0.01, thermal aging temperature be 150 DEG C, carry out thermal aging test, thermal aging time is 72 hours, and sampling subsequently is tested；
(4) test insulating paper heat conductivity, characterizes transformer insulation oil active sulfur situation。
Test result is as shown in Figure 2。
React generation corrosion product (cuprous sulfide etc.) due to copper conductor after corroding spread with benzyl disulfide (DBDS) and be deposited on insulating paper, thus causing that insulating paper overall thermal conductivity changes。Heat conductivity according to the insulating paper not having corrosion product to deposit should about 0.20W/ (m.K), when after corrosion, the heat conductivity of copper winding insulation paper is lower than 0.20W/ (m.K), insulating oil exists the active sulfur of variable concentrations, and the numerical value according to heat conductivity judges the concentration of active sulfur in insulating oil。
Adopt laser heat conducting instrument test insulating paper heat conductivity, to characterize transformer insulation oil active sulfur situation。Fig. 1 be laser shine method test insulating paper Determination of conductive coefficients schematic diagram, first heating source is launched a branch of short pulsed light and is radiated at the lower surface of sample, then heat up accordingly with infrared detecting set record sample surfaces, and the signal dropping temperature sounder in an initial condition is amplified and corrects, make temperature rise curve can reflect the change being irradiated the specimen temperature caused by laser, it is possible to test heat conductivity within the scope of room temperature to 200 DEG C。
Embodiment 2
The present embodiment provides the characterizing method of a kind of transformer insulation oil active sulfur, and particular content is identical with embodiment 1 with step, is different in that, then adding concentration in step (2) in insulating oil is 0ppm benzyl disulfide (DBDS)。
Test result is as shown in Figure 2。
Embodiment 3
The present embodiment provides the characterizing method of a kind of transformer insulation oil active sulfur, and particular content is identical with embodiment 1 with step, is different in that, then adding concentration in step (2) in insulating oil is 500ppm benzyl disulfide (DBDS)。
Test result is as shown in Figure 2。
Embodiment 4
The present embodiment provides the characterizing method of a kind of transformer insulation oil active sulfur, particular content is identical with embodiment 1 with step, being different in that, then adding concentration in step (2) in insulating oil is 1000ppm benzyl disulfide (DBDS)。
Test result is as shown in Figure 2。
From figure, 2 it can be seen that the heat conductivity of insulating paper is in the heated perimeter of 20 DEG C～200 DEG C in the embodiment of the present invention 1～4, presents and first increases the trend reduced afterwards；Simultaneously along with the increase of benzyl disulfide (DBDS) concentration, insulating paper surface precipitation thing content increases, the heat conductivity of insulating paper presents downward trend, because in real transformer running, covered wire group surface precipitation active sulfur compound, the heat conductivity that can cause insulating paper reduces, and the capacity of heat transmission is degenerated。
Simultaneously, insulating paper surface precipitation active sulfur compound can cause that insulating paper partial discharge quantity increases, both makes insulating paper surface produce hot-spot to a great extent, and the degree of aging of insulating paper is closely related with aging temperature, hot-spot can accelerate the aging of insulating paper, the degree of roughness on insulating paper surface increases further so that, the partial discharge quantity on insulating paper surface continues to increase and the heat conductivity of insulating paper can reduce further。When insulating paper produces hot-spot, cuprous sulfide can be made to be more prone to be deposited in insulating paper surface, thus forming a nauseating circulation, transformer fault may finally be caused。
So characterize active sulfur transformer insulation oil from qualitative and quantitative angle simultaneously, not only can confirm the existence of active sulfur in transformer insulation oil and the size of amount in time, accurately, more can get rid of potential safety hazard in time, be of value to the risk assessment to transformator effective operation and running status assessment。
Claims (8)
1. the characterizing method of a transformer insulation oil active sulfur, it is characterised in that comprise the steps:
(1) copper conductor is slit into the sample of uniform length, then with insulating paper by described sample tight, subsequently the sample that insulating paper wraps up is placed in the vacuum drying oven that baking temperature is 85 DEG C～95 DEG C, dry, drying time is 43～53 hours, being subsequently cooled to 38 DEG C～42 DEG C, the sample after using the new transformer oil that deoxidation gas dewaters to infiltrate described cooling subsequently, infiltrating time is 10～14 hours；
(2) according to 1g oil: 0.5cm2The ratio of copper adds insulating oil in conical flask, then in insulating oil, add benzyl disulfide, copper conductor sample after new transformer oil infiltration in step (1) is put into conical flask simultaneously, and immerse insulating oil, subsequently conical flask is placed in vacuum nitrogen case, evacuation and under vacuum state nitrogen charging to a normal atmosphere, seal under airtight, to be full of nitrogen environment subsequently；
(3) by the copper conductor sample after encapsulation process in step (2) as, in vacuum ageing oven, controlling vacuum, thermal aging temperature and thermal aging time, carry out thermal aging test, sampling subsequently is tested；
(4) test insulating paper heat conductivity, characterizes transformer insulation oil active sulfur situation。
2. the characterizing method of transformer insulation oil active sulfur according to claim 1, it is characterised in that the baking temperature in described step (1) is 90 DEG C, drying time is 48 hours。
3. the characterizing method of transformer insulation oil active sulfur according to claim 1, it is characterised in that in described step (1), infiltrating time is 12 hours。
4. the characterizing method of transformer insulation oil active sulfur according to claim 1, it is characterised in that in described step (2), the concentration of benzyl disulfide is 0ppm～1000ppm。
5. the characterizing method of transformer insulation oil active sulfur according to claim 1, it is characterised in that in described step (3), vacuum is 0.01～0.9。
6. the characterizing method of transformer insulation oil active sulfur according to claim 1, it is characterised in that in described step (3), the temperature of heat ageing is 80 DEG C～165 DEG C。
7. the characterizing method of transformer insulation oil active sulfur according to claim 1, it is characterised in that in described step (3), thermal aging time is 24～1000 hours。
8. the characterizing method of transformer insulation oil active sulfur according to claim 1, it is characterised in that in described step (4), test insulating paper heat conductivity is to adopt laser heat conducting instrument to measure insulating paper heat conductivity。
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| CN108535328A (en) * | 2018-03-12 | 2018-09-14 | 重庆大学 | Insulating oil sulfur corrosion quantitative testing device based on balanced bridge and method |
| CN109916953A (en) * | 2019-05-06 | 2019-06-21 | 山东众途复合材料有限公司 | The measuring method of the thermal coefficient of gap shape heat-barrier material under superhigh temperature vacuum or inert atmosphere |
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| CN108535328A (en) * | 2018-03-12 | 2018-09-14 | 重庆大学 | Insulating oil sulfur corrosion quantitative testing device based on balanced bridge and method |
| CN109916953A (en) * | 2019-05-06 | 2019-06-21 | 山东众途复合材料有限公司 | The measuring method of the thermal coefficient of gap shape heat-barrier material under superhigh temperature vacuum or inert atmosphere |
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Application publication date: 20160622 |