Effects and Corrections of Oil Replacement upon Furfural Content in Insulating Oil and Aging Assessment of Insulation Paper of Power Transformers
Lin Yuandi1, Liao Ruijin1, Zhang Yiyi1,2, Liu Haibin1
1. State Key Laboratory of Power Transmission Equipment & System Security and New Technology Chongqing University Chongqing 400044 China; 2. Guangxi Key Laboratory of Power System Optimization and Energy Technology Guangxi University Nanning 530004 China
Abstract:In order to investigate the changing of furfural content in insulating oil after oil replacement and its effects on insulation paper aging assessment, accelerated thermal aging test of oil-paper insulation samples was conducted at 130℃ in the laboratory. The aged insulating oil was replaced at the early, middle and late aging stages respectively, and the furfural content in oil was compared. The results showed that the furfural content greatly declined after oil replacement. The difference of furfural content in oil before and after oil replacement decreased with aging. If oil replacement was neglected, the aging assessment of paper will cause over-estimation, especially at the early stage after oil replacement. Furfural modification function was defined as the ratio of furfural in oil at the same time point before and after oil replacement. The changing rules of furfural modification function were studied and used to correct the furfural content. It was shown that the modification function could effectively improve the aging assessment results. The furfural modification function was generalized to operation temperature, which can correct the furfural content of in-service transformers.
林元棣, 廖瑞金, 张镱议, 柳海滨. 换油对变压器油中糠醛含量和绝缘纸老化评估的影响及修正[J]. 电工技术学报, 2017, 32(13): 255-263.
Lin Yuandi, Liao Ruijin, Zhang Yiyi, Liu Haibin. Effects and Corrections of Oil Replacement upon Furfural Content in Insulating Oil and Aging Assessment of Insulation Paper of Power Transformers. Transactions of China Electrotechnical Society, 2017, 32(13): 255-263.
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