A new approach to condition assessment and lifetime prediction of paper and oil used as transformer insulation

Kraft paper (cellulose) immersed in mineral oil is used as the insulation system for copper windings in large power transformers. As the system ages under load, the paper and oil can degrade potentially leading to catastrophic failure. Reliable condition monitoring, condition assessment and failure prediction of the insulation system is central to effective transformer asset management and non-destructive/non-invasive approaches are preferred. In this paper we will show that near infrared (NIR) spectroscopy combined with chernometrics is capable of providing rapid non-destructive condition assessment of the paper and the oil components individually