The invention relates to a method for detecting
methanol in insulating oil based on terahertz time-domain
spectroscopy, which comprises the following steps of: researching terahertz spectrum characteristics of
formaldehyde in the insulating oil, and extracting spectrum characteristic parameters capable of representing the
methanol content by adopting a transmission-type terahertz spectrum technology; the
quantum chemical
simulation auxiliary research of the terahertz time-domain
spectroscopy comprises the following steps: analyzing
chemical bond and functional group sources of spectral characteristics obtained by a
quantum chemical
simulation method, and determining a characteristic
fingerprint spectrum of
methanol as a theoretical basis for subsequent quantitative analysis;
signal reconstruction and environment compensation: performing
signal reconstruction and environment compensation by integrating multi-sensor data so as to improve the
measurement precision; terahertz time-domain
signal reconstruction and quantitative detection relation model research are carried out, and a high-precision quantitative analysis model is constructed by analyzing spectral characteristics of a ternary mixture of methanol,
furfural and water. According to the invention, the precision and efficiency of methanol detection are improved, and the anti-interference capability and real-time monitoring performance of the
system are obviously enhanced.