Ageing studies on paper and oil to assess the condition of solid insulation used in power transformers

The present study involves the ageing of insulation paper and oil samples at three different temperatures, i.e. 85 /spl deg/C, 100 /spl deg/C and 115 /spl deg/C, for 1000 h in the laboratory. The deterioration in mechanical and electrical properties of paper as a result of ageing has been correlated with a fall in the degree of polymerization and a rise in furan content.