Condition monitoring of the bulk insulation of distribution transformers by electrical and chemical techniques

The paper addresses the assessment of insulation condition in distribution transformers. Electrical diagnostic techniques have been applied to several distribution transformers of different ages and ratings. Correlation between dissipation factor and interfacial polarization spectra (IFS) parameters are examined. Gel permeation chromatography (GPC) has been used for observing the change in molecular weight of the cellulose polymer. The correlation between interfacial polarization parameters and peak molecular weights are also examined.<>