随着变压器的长期运行,变压器油中会产生微生物,微生物代谢产物会影响变压器油的品质.本文结合三维荧光光谱(3D-EEM)、紫外光谱和红外光谱(FTIR)分析变压器油中微生物产生的胞外聚合物(EPS)含量、组成及结构的变化,对比分析新油及故障油中有机物的种类,考察EPS对变压器油品质的影响.结果表明:变压器油长期运行会生成C=C和C=O特征官能团,颜色加深,在波长为190~400 nm的近紫外区吸光度明显增大.新油、运行油及故障油中蛋白质(PN)含量始终高于多糖(PS)含量,PN是EPS的主要成分,故障油EPS的荧光发射等高圈的数量减少,主要存在O-H、C-H、C=O和不饱和键.与新油相比,故障油中含水量最多增大5倍,酸值提高40倍.
With the long-term operation of transformers,microorganisms will be produced in transformer oil,and the microbial metabolites can affect the quality of transformer oil.In this paper,the changes of the content,composition,and structure of extracellular polymeric substances(EPS)produced by microorganisms in the transformer oil were analyzed by using three-dimensional fluorescence spectroscopy(3D-EEM),ultraviolet spectroscopy,and Fourier transform infrared spectroscopy(FTIR).The types of organic compounds in new oil and fault oil were compared and analyzed,and the effect of EPS on the quality of transformer oil was investigated.The results show that C=C and C=O characteristic functional groups generate in the transformer oil after long-term operation.The color of the oil in darkened,and the absorbance increases significantly in the near ultraviolet region with the wave length of 190 nm-400 nm.The content of protein(PN)in new oil,running oil,and fault oil is always higher than that of polysaccharide(PS),and PN is the main component of EPS.The number of fluorescent emission contour rings of EPS in fault oil decreases,mainly including O-H,C-H,C=O and unsaturated bond.Compared with new oil,the water content of faulty oil increases by up to 5 times,and the acid value is 40 times higher than that of new oil.