Space charge behavior in electrical insulation under high fields

This paper deals with the space charge behavior in polymeric power cable insulations. The purpose of this study has two aspects; one is the development of DC cable, and the other is the development of diagnosis techniques based on the space charge behavior. For this study, a new method that can measure the space charge in cables applying very high voltages was developed. Some interesting results on the change in time of space charges in thick insulation under the fields up to 1 MV/cm were obtained. It was also shown that there is a close relation between the water tree degradation and the space charge in the insulation, and that the space charge behavior is applicable to the diagnosis of power cables