Laboratory Model for Evaluation of Incipient Transformer Thermal Fault Involving Insulating

In order to age thermally upgraded kraft paper immersed in insulating oil without aging the oil, an “aging device” was built in which a copper electric resistance was covered with insulating paper and the setup was immersed in insulating oil contained in a vessel. The oil was water cooled to keep its temperature below 60° C, while paper's temperature was raised up to 500 °C. The experiment allowed the determination of the CO2/CO rate variation against aging time and temperature. The generation of other decomposition products, namely furan compounds, methanol and ethanol was also determined against aging time and temperature. Paper aging status was also determined through degree of polymerization (DP). The aging of oil was also monitored.