The estimation of residual life of the transformer (even in approximation) is a dream. However is possible, by adequately monitoring some parameters, to estimate the state and rate of thermal degradation of papers.
This can be made with different approaches.
Equivalen DP estimation:
Some authors defind relationships between 2-FAL concentration (or better total 2-FAL generated) and DP of the paper in the hot spot.
Estimation of degradation rate:
More credibly, on the base of rate of increase of 2-FAL and carbon oxides it is possible to estimate the thermal aging rate in defined periods: this approach needs more frequent controls, but seems to be more efficient.
Equivalent DP estimation according to different authors
