不平等電界下の空間電荷分布の変化とエポキシ樹脂の絶縁劣化

抄録

Reliability in the insulating materials is necessary in order to supply stable power. However, the non-uniform electric field is caused by foreign matters or voids in the insulating material. The deterioration of insulating material is accelerated due to the non-uniform electric field and it finally leads to a dielectric breakdown. It is likely that the space charge distribution is related to the deterioration of the insulating material. The pulsed electro-acoustic (PEA) method can make it possible to detect the space charge distribution and to get the valuable information for the deterioration diagnosis. In this study, a line-plate electrodes system was used to bring non-uniform electric field and the epoxy resin was inserted as the insulating material between the line electrode and the plate electrode. The changes of space charge distribution were observed under non-uniform electric field before the dielectric breakdown. As a result, this study indicates that the charge is injected from the line electrode and the space charge distribution changes due to the deterioration of the epoxy resin.