The distribution behavior of furfural in insulation systems is influenced by the oil-pressboard mass ratio. In addition, the equilibrium distribution of furfural between oil and pressboard will be disturbed after oil replacement. Therefore, it is of great significance to study the distribution ratio of furfural in oil with various oil-pressboard mass ratios after oil replacement. In this research, an accelerated thermal aging experiment and oil replacement experiment were conducted in the lab. Furthermore, the equilibrium characteristics of furfural dissolved in oil with various oil-pressboard mass ratios were studied. Multiple regression analysis was used to analyze the relationship between the oil-pressboard mass ratios and the distribution ratio of furfural in oil. The equilibrium distribution model of furfural was thus obtained. Afterwards, the modified furfural distribution model under oil replacement conditions was established. A novel scheme is provided for analyzing the equilibrium characteristics of furfural under various oil-pressboard mass ratios after oil replacement. The work of this paper is expected to improve the accuracy of furfural analysis.
Keywords: furfural analysis; oil replacement; oil–pressboard insulation; oil–pressboard mass ratio; transformer.