Understanding copper corrosion due to sulphur in oil of large transformers by different approaches

This paper discusses the chemical and dielectric methods of analysis of aging of paper oil insulation due to copper corrosion which occurs in presence of reactive and corrosive sulphur in transformer oil. Results of Chemical Analysis and dielectric measurements are presented and discussed for understanding the usefulness of these methods in arriving at a comprehensive method to explain the effects of copper corrosion in transformers.