Space charge behaviour in LDPE films under 0.5-4.0 MV/cm fields

We have been observing space charge profiles in low-density polyethylene under the extremely high electric field with short interval to clarify the relationship between space charge accumulations and electric breakdown. In this experiments, a large amount of charge packet injected from electrodes into bulk was observed. Furthermore, the dependence of applied electric field on space charge behavior was investigated. From the results, it is found that the injected charge packet moved faster and deeper under relatively lower electric field rather than that under higher electric field. When breakdown happens in a specimen, the maximum intensity of electric field in each specimen was almost same. In this paper, we will introduce these curious and interesting results.