DC Partial Discharge Characteristic of Insulating Paper in High Viscosity Insulating Oil and Charge Behavior

Abstract

In long-distance DC submarine cables, insulating oil depletion phenomenon occurs due to limitations in pressure transmission distance. Therefore, the high viscosity insulating oil such as high viscosity oil is promising. However, if the unexpected bubbles are occurred in the high viscosity oil, partial discharge in bubbles may reduce insulation performance of the cable. In addition, the partial discharge promote the degradation of insulating oil and insulating performance may reduce. In this paper, it is investigated DC partial discharge inception voltage and repetition rate of DC partial discharge occurrence of the kraft paper impregnated with the high viscosity insulating oil. Furthermore, the charge behavior was discussed.