Analysis of methyl formate dissolved in transformer oil by laser Raman spectroscopy

As an aging product of insulating paper, methyl formate dissolved in transformer oil can reflect the progress of oxidization and affect the insulating property of transformer oil. And the concentration of methyl formate dissolved in transformer oil has been given more and more attention. Confocal Laser Raman spectroscopy (CLRS) can directly perform non-contact fast measurement to transformer oil samples, especially being suitable for online monitoring. Using CLRS to detect the concentration of methyl formate dissolved in transformer oil can overcome many disadvantages of traditional methods. In this paper, the application of CLRS in the detection of methyl formate dissolved in transformer oil was studied. Firstly, Gaussian 09W was applied to analyze the Raman spectrum of methyl formate. Based on the CLRS test platform set up in the lab, oil samples with different methyl formate concentrations were detected. And methyl formate was characterized by Raman signal at 903 cm−1, where can be used to quantitative analysis with the least squares method. The results show that LRS can be used in the analysis of methyl formate dissolved in transformer oil, which lays the foundation for the online monitoring of dissolved methyl formate in transformer oil with CLRS.