Development of gas chromatography for dissolved gas in oil based on nitrogen plasma discharge detection principle

Abstract

The gas chromatography detection technology of dissolved gas in oil based on the nitrogen plasma discharge detection principle was studied. This technology detected the characteristic emission light emitted by the excited molecule after the ionization of the detected molecule motivated by the plasma generated by the nitrogen molecule under the action of a high-energy electromagnetic field and realized the quantitative detection of different molecules. Compared with the previous national standard commonly used hydrogen flame ionization detector (FID) and thermal conductivity detector (TCD) gas chromatography, it has a lower detection limit. The advanced chromatographic system with the original process realizes the detection of dissolved gas in transformer oil, which has good linearity and repeatability and can ensure the accuracy of measurement data. The analysis only used nitrogen and did not use hydrogen to prevent explosion hazards. Nitrogen is at least ten times cheaper than helium and is more economical than helium ion chromatography in consumables. The device can detect the small content of the characteristic gas in the transformer oil and the slight change of the content to prevent the occurrence of dangerous accidents.