某电厂主变压器油中腐蚀性硫问题分析及处理措施

Cause Analysis and Treatment of Sulfur Corrosion in Transformer Oil in a Power Plant

某电厂1号、2号主变压器油击穿电压偏低,总烃含量持续升高。为找出问题所在,对油品进行了一系列试验,包括扫描电镜扫描、元素分析、X射线衍射分析及腐蚀性硫试验,其结果为变压器油中全硫及腐蚀性硫分较高,变压器油发生了硫腐蚀,含硫物质与绕组材料(铜)发生反应后生成黑色的Cu2S及Cu4SO4(OH)6,影响变压器的绝缘性能,导致油中总烃含量升高。再生处理并辅以添加钝化剂的方法可降低油中全硫和腐蚀性硫分,减缓硫对铜片的腐蚀。

The breakdown voltages of transformer oil in Main Transformers 1 and 2 are low and their total hydrocarbon contents are continuously increasing. Therefore, a series of tests are performed to figure out the reasons. The tests include SEM, elemental analysis, X-ray diffraction analysis and corrosive sulfur tests. The results show that the total sulfur and corrosive sulfur contents in the oil are high, which causes sulfur corrosion, and a reaction of the sulfur-containing substance with winding material takes place, producing the Cu2S and Cu4SO4（OH）6, which affects the transformer＇ s insulating function and leads to the increasing of g the hydrocarbon contents. Recycling treatment and passivator adding to the oil can reduce the contents of total and corrosive sulfur and alleviate copper corrosion by sulfur.