Discharge of polypropylene films surface negatively charged

The space charge, present in dielectrics materials, such as the polypropylene films or fibrous nonwoven media, is not generally appreciated. Indeed, the local intensification of the electrical field can provide local discharges. It is necessary to eliminate these charges. The aim of this work is to propose a simple device for the elimination of electric charges and to evaluate its efficiency using non-contact measurements of surface potential. The characterization of the state of charge is obtained by the surface potential before and after charges elimination. To control the neutralization, the use of the triode configuration is a wise choice. Indeed the grid connected to the earth makes it possible to impose a zero potential on the surface of the dielectric.