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为研究硫腐蚀反应的定量表征方法及其对绝缘纸老化的影响机制,对运行6年的腐蚀性尼纳斯油样开展了加速老化实验,并与普通 25#变压器新油进行比对.对老化过程中变压器油样总硫浓度、油样质量测试后发现,油中硫元素的绝对含量随老化时间延长呈增大趋势,说明绝缘纸裂解使硫成分进入油中,造成总硫浓度升高.通过引入绝缘纸聚合度(degree of polymerization,DP)、总硫浓度和油样质量三个特征参量,建立了定量表征硫腐蚀程度的新判据.对老化过程中内、外层纸的含水量、酸值和聚合度进行比较分析,结果表明:在一定氧气含量环境下,因硫腐蚀反应的影响,老化初期内层纸的含水量小于外层纸,但随着老化时间增加,二者差距逐渐减小,到老化后期,内层纸水含量反超外层纸;0~ 24h内,外层纸酸值略大于内层纸,24~72h内,内层纸酸值迅速增长,明显大于外层纸;内层纸聚合度大于外层纸聚合度,而随着老化时间增加,内、外层纸的聚合度差距越来越小.“,”To study quantitative characterization of the sulfur-corrosion reaction and its influencing mechanism on the insulation paper aging, accelerated aging tests regarding a corrosive oil sample operational for 6 years were carried out, and comparison were made with a new oil sample denoted as 25# oil. According to measurement of the sulfur concentration and the weight of the oil samples, the sulfur element in the oil was found to increase with time, which indicated that sulfur contents were released from paper pyrolysis and spread into the oil with sulfur concentration rise of the oil. With three specific parameters being combined, namely degree of polymerization (DP), sulfur concentration and weight of the oil, a new method to quantitatively characterize sulfur-corrosion was established. Comparative analysis was done with regard to water moisture, acidity and DP of both the inner and outer layer of paper in the corrosive oil sample. It was found that, with limited oxygen content in the sulfur-corrosive oil-paper insulation, in the initial aging period there was less water moisture in the inner layer of paper than in the outer one, but the gap narrowed later on and finally the inner layer exceeded the outer layer. In the period from time zero to 24h, the acidity of the outer layer paper was a little larger than that of the inner layer, however, the acidity of the inner layer paper increased rapidly in the following period from 24h to 72h and well surpassed the outer layer paper acidity. The DP value of the inner layer paper was always larger than that of the outer layer, but both gradually came closer to each other with the aging time increasing.