Influence of naturally existing micro particles on AC and impulse breakdown strengths of industrially purified transformer oil

Abstract

Breakdown strengths of insulating oil are influenced by micro particles in oil and the relationships between the breakdown phenomena of insulating oil and micro particles in oil are reported by many authors. However many of them are the results of experiments, which were carried out by adding micro particles into oil artificially, and some of the results are obtained by filtering oil, but in the experiments the numbers of particles were not investigated quantitatively.[1]