Dielectric Properties of Insulating Liquids Under High Electrical Stress and Nonuniform Fields

Abstract

This thesis presents the results of an experimental investigation into the effect of enforced co-field motion and cross­ field motion on the conduction current in transformer oil under

eiectrode geometry. The piane eiectrode was either soiid or fitted

\;Vith a 0.16 mm mesh screen.

Befo;e each conduction current test, a complete set of breakdown voltage tests '."!ere carried out, to determine the voltages at which the conduction current wouid be measured.

The present work is characterized by eiiminating any human inteiference in conduction current measurements, recording and plotting by using a highly sensitive electronic electrometer (with built in memory for measuring the conduction current) directly connected to the test cell & interfaced '.".lith a computer. Conduction current vaiues were recorded at preset intervais that varied from 360

Tests on oil were carried out for negative and positive point polarities under the following conditions:- 1- Degassed oii .

4- Oil containing 1-methylnaphtha!ene .