Abstract:This paper studied how insulating oils, namely mixed insulating oil of mineral oil & natural ester and 25# mineral oil, influence thermal aging rate of insulating paper and verified that the mixed insulating oil can effectively inhibit the thermal aging rate of insulating paper. For an in-depth investigation of the inhabitation mechanism, the X-ray Photoelectron Spectroscopy (XPS) was employed to obtain the XPS carbon spectra from both the surface and the inside of insulating papers immersed and aged in aforementioned insulating oils respectively, furthermore, combined with traditional parameters indicating aging extent of insulating paper: degree of polymerization (DP) and furfural content in oil, the spectra were thoroughly studied and analyzed. The obtained results reveal: a new group—ester group (O-C=O) is generated in the insulating paper aged in mixed oil, which is believed as the prime reason why the mixed oil inhibits the thermal aging rate of insulating paper; The quantitative analyses of XPS carbon spectra indicate the carbon atom of the newly generated ester group mainly oriented in the glucose ring of the cellulose chain, which provides valuable information for anti-aging modification of insulating oil and insulating paper in future.
廖瑞金, 尹建国, 杨丽君, 梁帅伟, 郝建. 矿物油-天然酯混合绝缘油减缓绝缘纸热老化速率机理的XPS研究[J]. 电工技术学报, 2011, 26(10): 136-142.
Liao Ruijin, Yin Jianguo, Yang Lijun, Liang Shuaiwei, Hao Jian. XPS Study on the Inhibition Mechanism of Newly Developed Mixed Insulating Oil on the Thermal Aging of Insulating Paper. Transactions of China Electrotechnical Society, 2011, 26(10): 136-142.
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