Measurements of conduction current and electric field distribution up to electrical breakdown in two-layer polymer film

We reported an investigation of conduction current related to electrical breakdown phenomena in a low-density polyethylene (LDPE) film. Space charge distribution and external circuit current have been simultaneously measured up to electrical breakdown in a one-layer 100 μm thick LDPE film under DC voltage in order to know the relationship between the conduction current and the electrical breakdown. The results showed that the electrical breakdown in the one-layer LDPE film was more affected by the conduction current rather than the maximum electric field within the sample. In this paper, the electric field distribution and conduction current were measured on two-layer LDPE film to investigate the conduction current increase related to the breakdown in high temperature region. The measured conduction current increased with temperature. The changes of space charge distribution, electric field distribution and conduction current with temperature suggested the carrier injection and extraction on both positive and negative charges became active with temperature