INFLUENCE OF CORONA CHARGING ON SURFACE POTENTIAL DECAY IN INSULATING MATERIALS

Abstract

In this paper, an experimental investigation on surface potential decay (SPD) after negative corona charged polyethylene terephtalate (PET) is presented. The effect of the charging time tp on the decay characteristic of surface potential is presented for samples of two different thicknesses (0.5mm, 1mm). The measurements are carried out in situ, in a commercial climatic chamber in which humidity and temperature are controlled. The experimental results show clearly that the charging condition when a corona source is employed can have a marked effect on the decay characteristics of charge on PET samples. It is suggested that the degree of exposure PET surface to the
light and the excited gas molecules from the corona discharge play an important role and acts on the kinetics of potential decay.