Internal Discharges in Polyethylene with an Artifical Cavity

Internal discharges were studied in a cylindrical cavity. Discharges were found to tend to be localized or fractionized from the measurements of apparent charge of maximum discharges, repetition rate of discharge pulses and inner-surface resistivity in cavities and from the observation on discharges with a microscope. Phenomena of internal discharges are easily influenced by physical properties of the inner-surface of a cavity, especially the electrical resistivity to be subject to change due to the discharge themselves.