Research on the relationship between characteristic parameters and transformer life

Status monitoring and life-cycle management for the power equipment is an inevitable requirement of modern grid operation. This paper collects some commonly used state variables, like absorption ratio, dielectric loss, dielectric oil breakdown voltage, etc. and analyze the track of them as the increase of transformer running time. With the help of regression analysis and hypothesis test, the relationship between these state quantities and running time is studied thoroughly. Research shows, Electrical test data as dielectric loss, etc. are mainly affected by the process of transformer oil, and they are not effective features for transformer life prediction. The contents of CO and CO2 have strong correlation with the transformer running time and they are characteristic parameters for transformer residual life prediction.