investigation of oil temperature effect on aging marker content of insulating paper in power transformers by gas chromatography method

Insulating paper aging of power transformers, a reliability factor for this equipment, can be evaluated by non-destructive methods such as measuring chemical markers’ content in transformer oil. since the sampling temperature of oil can affect the accuracy of laboratory measurements, the correlation between novel aging marker methanol and the degree of polymerization (dp) of insulating paper has been studied in this study. temperature correction factors have been obtained for the markers (2-fal, water, and methanol), and the under-load transformers’ data has improved the correlation formula. sampling from a real transformer was carried out to optimize the calculated estimation formula. various experiments have been performed on them, and their results have been analyzed. the real dp was also measured for the insulating papers sampled at the overhaul stage. the optimized model for insulating paper dp calculation using a temperature-corrected concentration of methanol in insulating oil has been provided in this work.