Research on Corrosive Sulfur and Temperature Effect in Transformer Oil

2015

AMM

Self Cite

Copper testing strips are wrapped with three layers of Kraft paper and carried out aging experiment in corrosive sulfur contaminated insulating oil at 150 °C for 10 days. It is found that the copper sulfide is first formed on the surface of copper and tainted to the inner side of the insulation paper. Then the copper sulfide permeates through the paper and damages the dielectric property. In addition, flaking mechanism on the transformer failure is proposed. On the basis of this observation, different concentration of Irgamet 39 used as passivator is treated with the transformer oil containing corrosive sulfur, investigating the acidity, dielectric loss and corrosion to seek optimized condition. At last, long term stability of Irgamet 39 is studied by means of 208 transformers in service.

Section: Mechanism Of Dbds On the Corrosion Of Coppermentioning

confidence: 89%

Mechanism of DBDS and Irgamet 39 on the Corrosion and Suppression of Copper in Transformers

Zhao

2015

AMM

Self Cite

“…Sulfur exists in two states:stable compound and volatile compound.The volatile sulfur compound, which can corrode the metal,including elemental sulfur,hydrogen sulfide and mercaptans, is also known as the corrosive sulfur.Stable compound can convert into volatile compounds at high temperature and under the catalysis of mental.Corrosive sulfur in power transformer can react with copper wire and cuprous sulfide can be produced in the surface of mental.Due to the electrical properties of cuprous sulfide,the wire insulation strength will decreased gradually which can cause failure of the apparatus finally [15].…”

Section: A Comparative Study Of Four Kinds Of Transformer Oil's Corro...mentioning

confidence: 99%

Comparative Study on the Impurities Content of Hydrogenated Transformer Oil under Static Condition

Huang

et al. 2011

AMR

The impurities content of domestic hydrogenated transformer oil and three kinds of naphthenic transformer oil had been determined by using the specified experimental methods. A series of experimental data had been obtained, including mechanical impurities, particulate contamination, corrosive sulfur, sulfur content, total acidity and interfacial tension. The impurities content of four kinds of transformer oil were compared with the quality indicators of transformer oil on GB/T7595-2008. The results showed that the impurities content of the former was not so satisfying although it had excellent electrical properties and the technology needed to be improved.

“…Oil is used as a cooling and insulating medium in large, ultrahigh‐voltage electric power equipment with forced oil circulation. Recently, many insulation faults have occurred in 220–500 kV transformers and reactors of the Guangdong power grid [1]. The blue‐black and grayish deposits, which were verified to be due to Cu 2 S, were found on the surface of windings and insulating packages [2].…”

Section: Introductionmentioning

confidence: 99%

Research on influencing factors of corrosive sulfur attacking copper in insulating oil and prevention

IEEJ Transactions Elec Engng

2013

The influencing factors (temperature, electric field, and oxygen) of sulfur attack in transformer oil are studied through comparative tests on new oil, oil in service, and these two oils with the deactivator additive BTA (benzotriazole, C 6 H 4 N 3 H). The influence of these factors on the chemical reaction between copper and corrosive sulfur is analyzed in further. The results show that temperature, electric field, and oxygen can promote the reaction between copper and corrosive sulfur. Moreover, oxygen also accelerates the aging of the insulating oil. On the contrary, recharging nitrogen can remove oxygen and reduce sulfur's corrosive activity. Adding the BTA deactivator can also prevent corrosion, even during the accelerated aging of oil with oxygen.