Life Time Estimation Method for the Feeder Transformers

Abstract

In order to prevent damage and to extend the lifespan of equipment in railway power systems, it is necessary to detect early on any deterioration and to assess the residual lifespan of feeder transformers. As such a database containing information about the three main conditions affecting feeder transformers was constructed. First, load characteristics were researched to evaluate thermal deterioration. Second, analytical data of dissolved gas-in-oil was examined to evaluate damage from partial electric discharge. Third, the amount of furfural was investigated to evaluate the deterioration characteristics of insulating paper for feeder transformers. Based on the results of these investigations a lifespan estimation method for feeder transformers was developed. The validity of the estimation method was verified comparing experimental values with estimated values.