The composite insulation system of power transformers consisting of two insulation materials (cellulose and mineral oil) are the main insulation material of power transformer, the increase of moisture will reduce their insulation strength. Moisture equilibrium curves are the basis of power transformer moisture detection, however, the service data and theory analysis both indicate the present curves are not fit for old transformer. Therefore this research work is focused the law and mechanism of the impact of aging on moisture equilibrium of cellulose and mineral oil. In this paper theory of moisture absorption mechanism and impact factors of cellulose and mineral oil are analyzed. The various aged cellulose and mineral oil samples were analysis by thermal aging method. This research work is also analyzed the moisture equilibrium law and mechanism of cellulose and mineral oil, which have been both theoretical significance and applicable potentials.

Rafaqat Hussian Abbasi, Beijing Key Laboratory of High Voltage & EMC (NCEPU), China.

Rafaqat Hussian Abbasi "Insulation Materials of Transformer Using Chemical Mechanism of Moisture Absorption" International Journal of Engineering Works, Vol.1, PP.15-19, Sept. 2014

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