Observation and numerical analysis of space charge behavior in low-density polyethylene formed by ultra-high DC stress

We have been attempting the observation and numerical analysis of space charge behavior in low-density polyethylene (LDPE) formed by ultra-high DC stress to investigate the relationship between breakdown and space charge accumulation phenomena. It was found that when an ultra-high electric field over several MV/cm was applied to LDPE, a large amount of positive packet-like charge was injected from anode. The injected packet-like charge moved towards cathode electrode and stopped in bulk of the sample. We also found the depth of the injection from anode electrode is negatively proportional to the intensity of electric field. In this report, a numerical simulation of packet-like charge behavior is proposed which is based on the numerical analysis. Furthermore, the results of the simulation are compared with the measurement results.