A high field pulsed electro-acoustic apparatus for space charge and external circuit current measurement within solid insulators

A pulsed electro-acoustic system is described which enables electric fields up to 0.5 GV m(-1) to be generated in thin (100-300 mu m) insulating plaque samples with measurement of the dynamic net space charge density, as a function of temperature and of distance through the thickness of the sample, and the external circuit charging current. From these measurements, the dynamic electric field, potential and conduction current density distributions within low-density polyethene samples have been obtained and are reported.