Study on the thermal aging characteristics and bond breaking process of oil-paper insulation in power transformer

The degradation of transformer oil-paper insulation is decided by the chemical and physical processes in oil-paper insulation. The thermal aging plays the main role in the electrical and thermal degradation. In order to study aging mechanism of oil-paper insulation, accelerated thermal aging experiments in laboratory were performed. Four types of oil paper compounds, which are composed by regular transformer paper and thermal upgraded transformer paper and Naphthenic mineral oil, BIOTEMP vegetable oil, were thermally aged for 1500 to 9500 hours at 90 degrees C, 110 degrees C, 130 degrees C, respectively. The degree of polymerization (DP) and concentration of furfural dissolved in oil were measured at sampling period. The variation law of DP and furfural content in oil, the influence on aging rate caused by different kinds of oil and paper, and the linear relationship between furfural and DP were all investigated. Furthermore, bond breaking mechanism of cellulose during thermal aging was discussed based on Material Studio 4.0 software. These instructions give you basic guidelines for preparing papers for conference proceedings.