WO2012137350A1 - 硫化銅生成の抑制方法 - Google Patents
硫化銅生成の抑制方法 Download PDFInfo
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- WO2012137350A1 WO2012137350A1 PCT/JP2011/058928 JP2011058928W WO2012137350A1 WO 2012137350 A1 WO2012137350 A1 WO 2012137350A1 JP 2011058928 W JP2011058928 W JP 2011058928W WO 2012137350 A1 WO2012137350 A1 WO 2012137350A1
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- oil
- filled electrical
- alkyl group
- chain alkyl
- insulating oil
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F41/00—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
- H01F41/005—Impregnating or encapsulating
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B3/00—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties
- H01B3/18—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances
- H01B3/20—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances liquids, e.g. oils
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D5/00—Processes for applying liquids or other fluent materials to surfaces to obtain special surface effects, finishes or structures
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F27/00—Details of transformers or inductances, in general
- H01F27/08—Cooling; Ventilating
- H01F27/10—Liquid cooling
- H01F27/12—Oil cooling
Definitions
- the present invention relates to a method for suppressing copper sulfide generation in electrical insulating oil used in oil-filled electrical equipment such as oil-filled transformers.
- coil copper is used as the current-carrying medium. Insulating paper is wound around the coil, and electrical insulation is ensured so that the coil is not electrically shorted between adjacent turns.
- electrical insulation oil such as mineral oil is used for oil-filled transformers.
- Mineral oil and the like contain a trace amount of sulfur component, and this sulfur component reacts with coil copper placed in the electrical insulating oil to produce conductive copper sulfide, which can be generated on the surface of the coil insulating paper.
- copper sulfide when copper sulfide is generated, the insulation performance of the coil insulating paper is deteriorated, and the coil may be short-circuited between turns to cause dielectric breakdown (for example, Non-Patent Document 1).
- Non-Patent Document 2 the main causative substance of copper sulfide formation is dibenzyl disulfide which is a sulfur component contained in mineral oil (for example, Non-Patent Document 2). It is also known that the complex formed by the reaction of dibenzyl disulfide with coil copper diffuses in the electrical insulating oil and is adsorbed on the insulating paper, and then decomposes to form copper sulfide (for example, Non-Patent Document 3).
- a method for suppressing copper sulfide generation by suppressing the reaction between dibenzyl disulfide and coiled copper is known, and a method of adding an inhibitor to electrical insulating oil is widely used.
- the inhibitor include 1,2,3-benzotriazole (hereinafter abbreviated as “BTA”), Irgamet® 39 [N, N-bis (2-ethylhexyl)-(4 or 5) -methyl 1H-benzotriazole-1-methylamine: manufactured by BASF Japan Ltd.] is known (for example, Non-Patent Document 4).
- Non-Patent Document 4 When an inhibitor of copper sulfide formation is added to the electrical insulating oil, the inhibitor reacts with the coil copper to form a film on the coil copper surface. This formed film blocks and suppresses the reaction between dibenzyl disulfide and coiled copper, so that copper sulfide production can be suppressed (for example, Non-Patent Document 4).
- Irgamet 39 has a lipophilic long-chain alkyl group, so it has a higher solubility in electrical insulating oil than BTA, and it can be used as an electrical insulating oil without using a dedicated dissolving device that is required for BTA addition work. It can be dissolved (for example, Patent Document 1 and Patent Document 2). Therefore, when Irgamet 39 is added to the existing transformer, the field work is simplified, and there is an effect that the power failure time at the field can be shortened. Therefore, the application needs of Irgamet39 are increasing.
- the present invention can prevent the generation of hydrogen gas after the addition of the copper sulfide production inhibitor to the electrical insulating oil, and can suppress the copper sulfide production that can be carried out by the simplest possible method. It aims to provide a method.
- the present invention is a method for suppressing copper sulfide generation in electrical insulating oil in oil-filled electrical equipment, If the oil-filled electrical device is an open-type oil-filled electrical device, add a benzotriazole compound that does not have a long-chain alkyl group, When the oil-filled electrical device is a sealed oil-filled electrical device, a benzotriazole compound having a long-chain alkyl group is added.
- the benzotriazole compound having a long chain alkyl group is preferably N, N-bis (2-ethylhexyl)-(4 or 5) -methyl-1H-benzotriazole-1-methylamine.
- the oil-filled electrical device is preferably a large transformer.
- the present invention is a method for suppressing copper sulfide generation in electrical insulating oil in oil-filled electrical equipment, In advance, measure the oxygen concentration in the electrical insulating oil in the oil-filled electrical equipment, If the measured oxygen concentration is lower than 5000 ppm, add a benzotriazole compound having a long chain alkyl group, When the measured value of the oxygen concentration is 5000 ppm or more, the present invention also relates to a method for suppressing copper sulfide formation, which comprises adding a benzotriazole compound having no long chain alkyl group.
- the generation of hydrogen gas after the addition of the inhibitor to the electrical insulating oil can be prevented by selecting the type of the copper sulfide generation inhibitor according to the type of the oil-filled electrical device. And the suppression method of copper sulfide production
- This embodiment is a method for suppressing copper sulfide generation in electrical insulating oil in oil-filled electrical equipment, and the copper sulfide production inhibitor is controlled depending on whether the oil-filled electrical equipment is an open type or a sealed type. It relates to a method of selecting the type and adding the inhibitor to the electrical insulating oil.
- An oil-filled electrical device is an electrical device containing oil such as electrical insulating oil, and includes, for example, a transformer encapsulated with electrical insulating oil.
- An open oil-filled electrical device is an oil-filled electrical device that is not sealed, and a sealed oil-filled electrical device is a sealed oil-filled electrical device.
- the oil-filled electrical device is preferably a transformer, and more preferably a large transformer. In particular, when hydrogen gas is generated in a large transformer, it is costly to disassemble and inspect, and there is a possibility that the power supply may be stopped during that time, so there is a high need to prevent the generation of hydrogen gas.
- the benzotriazole compound is a compound having a benzotriazole skeleton, and in the present invention, a benzotriazole compound having no long-chain alkyl group and a benzotriazole compound having a long-chain alkyl group are the types of oil-filled electrical devices. It is properly used by.
- the long-chain alkyl is preferably an alkyl group having 1 or more carbon atoms, and more preferably an alkyl group having 1 to 8 carbon atoms.
- benzotriazole compound having no long-chain alkyl group examples include 1,2,3-benzotriazole (BTA), which is a commercially available C.I. V. I. (Registered trademark) can be used.
- BTA 1,2,3-benzotriazole
- benzotriazole compound having a long-chain alkyl group examples include N, N-bis (2-ethylhexyl)-(4 or 5) -methyl-1H-benzotriazole-1-methylamine, which is a commercial product. Irgamet 39 manufactured by BSAF Corporation can be used.
- This embodiment is a method for suppressing copper sulfide generation in electrical insulating oil in oil-filled electrical equipment, and measures the oxygen concentration in electrical insulating oil in oil-filled electrical equipment, and the measured value of oxygen concentration is predetermined. It is related with the method of selecting the kind of copper sulfide production
- the oxygen concentration in the electrical insulating oil in the oil-filled electrical device is actually measured and Irgamet 39 is used, the oxygen concentration is 5000 ppm, which is the oxygen concentration at which the influence on the generation of oxygen hydrogen gas suddenly increases. If the oxygen concentration is lower than this reference value, a benzotriazole compound having a long-chain alkyl group is preferentially added, and if the oxygen concentration is higher than this reference value, a long-chain alkyl group is present. Do not add benzotriazole compounds. According to this form, it is possible to suppress copper sulfide generation by a simple method while more reliably preventing hydrogen generation.
- Test Example 1 In order to investigate the influence of the contact state between the electrical insulating oil and oxygen, the amount of hydrogen gas generated after adding a copper sulfide formation inhibitor to the electrical insulating oil was investigated using electrical insulating oils with different oxygen-containing concentrations. . Specifically, put a polished copper wire, an inhibitor of copper sulfide formation, and an electrical insulating oil with different oxygen content in a sealed test vessel, and conduct a heating test in a hot air circulation type drying furnace, heating test The hydrogen gas concentration in the subsequent sealed test container was measured.
- paraffin-based mineral oil (new oil) used for oil-filled transformers was degassed in advance, and prepared with sufficiently low concentration of flammable gas such as hydrogen gas.
- the oxygen concentration (initial value) in this electrical insulating oil was 1000 ppm or less.
- the electrical insulation oil whose oxygen content concentration (initial value) is 5000 ppm, 10000 ppm, 15000 ppm, and 20000 ppm was also prepared.
- each oxygen-containing electric insulating oil is monitored for the oxygen concentration in the electric insulating oil while bubbling a certain amount of air, and the oxygen concentration is the above-mentioned oxygen concentration (5000 ppm, 10,000 ppm, 15000 ppm, 20000 ppm). When bubbling was reached, it was prepared by stopping bubbling.
- a bellows type stainless steel container capable of blocking the inflow of outside air and absorbing the expansion of the electric insulating oil by heating was used. Copper wire was coexisted to simulate coil copper in the transformer. Irgamet 39 (manufactured by BSAF Co., Ltd.) or BTA (C.V.I. (registered trademark): produced by Kyrest Co., Ltd.) was used as an inhibitor of copper sulfide formation.
- the heating temperature was 120 ° C. and the heating time was 24 hours.
- the hydrogen concentration in the electrical insulating oil after the heating test was measured by a gas chromatograph.
- FIG. 1 shows the relationship between the oxygen concentration (initial value) in the electrical insulating oil and the hydrogen concentration in the electrical insulating oil after the heating test.
- Irgamet 39 When Irgamet 39 is added, a large amount of hydrogen gas is generated in the electrical insulating oil having an oxygen concentration of 5000 to 20000 ppm in the electrical insulating oil, but hydrogen gas is generated in the electrical insulating oil having an oxygen concentration of 1000 ppm or less in the electrical insulating oil. There are few occurrences. That is, when Irgamet 39 was added to the electrical insulating oil, it became clear that the oxygen concentration in the electrical insulating oil greatly affected the amount of hydrogen gas generated. On the other hand, it can be seen that when BTA is added, the amount of hydrogen gas generated is small regardless of the oxygen concentration in the electrical insulating oil.
- Transformer types can be broadly divided into open-type transformers and sealed-type transformers, and a small tank called a conservator for the purpose of preventing oxidative deterioration of electrical insulating oil is provided in the upper part of the main tank. .
- the sealed conservator is provided with a rubber bag for suppressing contact between air and electrical insulating oil, it is possible to suppress dissolution of oxygen in the electrical insulating oil.
- the open-type conservator is not attached with a rubber bag like the closed-type conservator, and performs a breathing action through a hygroscopic respirator containing a hygroscopic material such as silica gel. For this reason, oxygen is easy to dissolve in the electric insulating oil as compared with the hermetic transformer.
- the electrical insulating oil to which BTA is added has a small amount of hydrogen gas regardless of the oxygen concentration. Therefore, the reliability of the oil-filled electrical equipment can be maintained by adding BTA to the oil-filled electrical equipment.
- BTA has a low solubility in electrical insulating oil, a dedicated melting device is required, and there is a concern that the outage time may be prolonged due to the occurrence of local construction.
- a benzotriazole compound having a long chain alkyl group such as Irgamet 39
- a benzotriazole compound having a long chain alkyl group such as Irgamet 39
- a benzotriazole compound having a long chain alkyl group (Irgamet 39 or the like) is preferentially added, and when the oxygen concentration is higher than this reference value, a long chain alkyl group
- a benzotriazole compound such as BTA
- the present invention is used for an oil-filled transformer has been described as an example.
- the present invention can also be used for other oil-filled electrical equipment in which electrical insulating oil is used as an insulating medium.
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Physics & Mathematics (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Manufacturing & Machinery (AREA)
- Organic Insulating Materials (AREA)
- Housings And Mounting Of Transformers (AREA)
- Lubricants (AREA)
Abstract
Description
前記油入電気機器が開放型油入電気機器である場合は、長鎖アルキル基を有しないベンゾトリアゾール化合物を添加し、
前記油入電気機器が密閉型油入電気機器である場合は、長鎖アルキル基を有するベンゾトリアゾール化合物を添加することを特徴とする、硫化銅生成の抑制方法である。
また、本発明は、油入電気機器内の電気絶縁油中における硫化銅生成の抑制方法であって、
あらかじめ、前記油入電気機器内の前記電気絶縁油中の酸素濃度を測定し、
酸素濃度の測定値が5000ppmより低い場合は、長鎖アルキル基を有するベンゾトリアゾール化合物を添加し、
酸素濃度の測定値が5000ppm以上である場合は、長鎖アルキル基を有しないベンゾトリアゾール化合物を添加することを特徴とする、硫化銅生成の抑制方法にも関する。
本実施形態は、油入電気機器内の電気絶縁油中における硫化銅生成の抑制方法であって、油入電気機器が開放型または密閉型のいずれであるかにより、硫化銅生成の抑制剤の種類を選択して、該抑制剤を電気絶縁油に添加する方法に関するものである。
本実施形態は、油入電気機器内の電気絶縁油中における硫化銅生成の抑制方法であって、油入電気機器内の電気絶縁油中の酸素濃度を測定し、酸素濃度の測定値が所定の基準値未満であるか、基準値以上であるかによって、硫化銅生成の抑制剤の種類を選択して、該抑制剤を電気絶縁油に添加する方法に関するものである。
電気絶縁油と酸素との接触状態の影響を調査するため、酸素含有濃度が異なる電気絶縁油を用いて、硫化銅生成の抑制剤を電気絶縁油に添加した後の水素ガス発生量を調査した。具体的には、密閉試験容器内に、研磨した銅線、硫化銅生成の抑制剤、および、酸素含有濃度が異なる電気絶縁油を入れて、熱風循環式乾燥炉で加熱試験を行い、加熱試験後の密閉試験容器の水素ガス濃度を測定した。
Claims (4)
- 油入電気機器内の電気絶縁油中における硫化銅生成の抑制方法であって、
前記油入電気機器が開放型油入電気機器である場合は、長鎖アルキル基を有しないベンゾトリアゾール化合物を添加し、
前記油入電気機器が密閉型油入電気機器である場合は、長鎖アルキル基を有するベンゾトリアゾール化合物を添加することを特徴とする、硫化銅生成の抑制方法。 - 前記長鎖アルキル基を有するベンゾトリアゾール化合物は、N,N-ビス(2-エチルヘキシル)-(4又は5)-メチル-1H-ベンゾトリアゾール-1-メチルアミンである、請求項1に記載の硫化銅生成の抑制方法。
- 前記油入電気機器は大型変圧器である、請求項1または2に記載の硫化銅生成の抑制方法。
- 油入電気機器内の電気絶縁油中における硫化銅生成の抑制方法であって、
あらかじめ、前記油入電気機器内の前記電気絶縁油中の酸素濃度を測定し、
酸素濃度の測定値が5000ppmより低い場合は、長鎖アルキル基を有するベンゾトリアゾール化合物を添加し、
酸素濃度の測定値が5000ppm以上である場合は、長鎖アルキル基を有しないベンゾトリアゾール化合物を添加することを特徴とする、硫化銅生成の抑制方法。
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
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PCT/JP2011/058928 WO2012137350A1 (ja) | 2011-04-08 | 2011-04-08 | 硫化銅生成の抑制方法 |
US13/881,080 US8728565B2 (en) | 2011-04-08 | 2011-04-08 | Method for inhibiting generation of copper sulfide |
JP2011533893A JP4852186B1 (ja) | 2011-04-08 | 2011-04-08 | 硫化銅生成の抑制方法 |
CN201180063059.XA CN103299380B (zh) | 2011-04-08 | 2011-04-08 | 抑制硫化铜生成的方法 |
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PCT/JP2011/058928 WO2012137350A1 (ja) | 2011-04-08 | 2011-04-08 | 硫化銅生成の抑制方法 |
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JP (1) | JP4852186B1 (ja) |
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WO2013080315A1 (ja) * | 2011-11-30 | 2013-06-06 | 三菱電機株式会社 | 油入電気機器における硫化銅生成の抑制方法 |
WO2014080451A1 (ja) * | 2012-11-20 | 2014-05-30 | 三菱電機株式会社 | 油入電気機器の診断方法およびメンテナンス方法 |
WO2016030984A1 (ja) * | 2014-08-27 | 2016-03-03 | 三菱電機株式会社 | 油入電気機器の診断方法 |
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JP2001311083A (ja) * | 2000-04-27 | 2001-11-09 | Mitsubishi Electric Corp | 絶縁油中の硫黄化合物の除去装置及び除去方法 |
JP2008544057A (ja) * | 2005-06-23 | 2008-12-04 | シエル・インターナシヨネイル・リサーチ・マーチヤツピイ・ベー・ウイ | 酸化安定性油配合物 |
JP2010027634A (ja) * | 2008-07-15 | 2010-02-04 | Mitsubishi Electric Corp | 油入電気機器および硫化銅の析出防止方法 |
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JPH0676635A (ja) * | 1992-08-31 | 1994-03-18 | Mitsubishi Electric Corp | 油入電気機器 |
JPH0679936A (ja) * | 1992-09-01 | 1994-03-22 | Ricoh Co Ltd | 記録装置 |
JP2001027634A (ja) * | 1999-07-13 | 2001-01-30 | Hitachi Ltd | 水質監視システム |
JP2002015919A (ja) | 2000-06-29 | 2002-01-18 | Mitsubishi Electric Corp | 電気機器の絶縁油特性改善装置 |
WO2009054155A1 (ja) * | 2007-10-26 | 2009-04-30 | Mitsubishi Electric Corporation | 油入電気機器の診断方法 |
JP2010028022A (ja) | 2008-07-24 | 2010-02-04 | Mitsubishi Electric Corp | 添加剤溶解装置 |
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- 2011-04-08 US US13/881,080 patent/US8728565B2/en not_active Expired - Fee Related
- 2011-04-08 WO PCT/JP2011/058928 patent/WO2012137350A1/ja active Application Filing
- 2011-04-08 JP JP2011533893A patent/JP4852186B1/ja not_active Expired - Fee Related
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JP2001311083A (ja) * | 2000-04-27 | 2001-11-09 | Mitsubishi Electric Corp | 絶縁油中の硫黄化合物の除去装置及び除去方法 |
JP2008544057A (ja) * | 2005-06-23 | 2008-12-04 | シエル・インターナシヨネイル・リサーチ・マーチヤツピイ・ベー・ウイ | 酸化安定性油配合物 |
JP2010027634A (ja) * | 2008-07-15 | 2010-02-04 | Mitsubishi Electric Corp | 油入電気機器および硫化銅の析出防止方法 |
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US8728565B2 (en) | 2014-05-20 |
US20130216698A1 (en) | 2013-08-22 |
JPWO2012137350A1 (ja) | 2014-07-28 |
JP4852186B1 (ja) | 2012-01-11 |
CN103299380A (zh) | 2013-09-11 |
CN103299380B (zh) | 2016-01-20 |
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