Corona inception voltage and electrical field analysis for coaxial, paraxial and point-plane geometries

CORONA INCEPTION VOLTAGE AND ELECTRICAL FIELD ANALYSIS FOR COAXIAL, PARAXIAL AND POINT-PLANE GEOMETRIES (M. Sc Thesis) Mehmet ZİLE GAZİ UNIVERSITY INSTITUTE OF SCIENCE AND TECHNOLOGY January 1999 ABSTRACT Corona discharge is responsible for considerable power losses from high voltage transmission lines and often leads to deterioration of insulation material by the combined action of the discharge ions bombarding the surface and the action of chemical components that are formed by the discharge. In addition, the biological effects of electrification, by ion flow on a person, animal or object are important. Investigation of the corona discharge is not only for the theoretical studies, but also for the industrial applications (such as high speed printers and electrostatic sprey and painting etc.). The main parameters of the space-charges; velocity, direction, and distribution. The measurement of electric field and current density under corona needs new and sensitive techniques. In the present work, the obtained experimental results of coaxial and paraxial system are used and compared with the theoretical (analytical and numerical) computations. In literature, there is limited knowledge related to drift and distribution of the space-charge between the electrodes. Corona discharge has significant importance, since the space- charges affects the electric field and current density profiles especially for non-uniform field distributions. In addition, negative dc corona characteristics for electrode spacings of up to 2 meters have been determined for rod/plane geometries. The present study is confined only the corona inception voltages Vi measured in this study for rod/plane gaps. The measured corona inception voltage obtained for gap distance of 50, 100, 150 and 200 cm. and compared with both the analytical and numerical (computer) methods and closed relationships are obtained. Science Code Key Words Page Number Adviser 608.02.07 Corona discharge, Corona inception voltage and field 113 Associate Prof Dr. M. Cengiz TAPLAMACIO?LU