Partial Discharge
Partial Discharge
an electrical discharge that occurs in gaseous inclusions within electrical insulation or over contaminated or damp sections of the surface of such insulation. Partial discharges cause solid insulation to age or deteriorate. To avoid the occurrence of partial discharges, materials used as insulation are subjected to special treatment, such as vacuum drying or the impregnation of voids with an electrically strong dielectric. In addition, whenever possible, the surface of insulation is kept free of contamination and moisture.