This paper presents an improved method for detecting methanol and the concentration of methanol in transformer oil-paper. Acetonitrile is used as an extractant, and methanol is detected by gas chromatography-mass spectrometry. Experiments show a linear correlation coefficient of this method that reaches 0.99 and the minimum detected concentration of methanol in transformer oil can be as low as 5.57 μg/L. In order to investigate the relationship between the methanol concentration and the degree of aging of insulating paper, an oil-paper insulation simulation system is designed. The experiment shows that there is a linear relationship between the logarithm of methanol concentration and the degree of polymerization, the linear correlation coefficient is greater than 0.94. An actual oil sample from a transformer is used to show that the method can be used to further study the methanol concentration.

中文翻译：

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一种改进的油纸绝缘中甲醇含量检测方法

本文提出了一种检测变压器油纸中甲醇和甲醇浓度的改进方法。以乙腈为萃取剂，用气相色谱-质谱法检测甲醇。实验表明，该方法的线性相关系数达到0.99，变压器油中甲醇的最低检测浓度可低至5.57 μg/L。为研究甲醇浓度与绝缘纸​​老化程度的关系，设计了油纸绝缘模拟系统。实验表明，甲醇浓度的对数与聚合度之间存在线性关系，线性相关系数大于0.94。