ELECTRICAL-FIELD DISTRIBUTION IN TRANSFORMER OIL

Developments in Kerr electro-optic measurement technology at our laboratory have made possible high resolution electric field measurements in nonpolar liquids. The electric field distribution in transformer oil has been studied at service stress levels in both the transient and steady state. The field distributions observed, are well described by a one-dimensional quantitative model (with measurable parameters) based on charge carrier generation through dissociation of a species of ion pairs in the liquid bulk. As two-dimensional measurements are also possible, an engineering tool now exists which can be used, for example, in the study of geometries relevant for converter transformer design.