Discharge characteristics on the surface of solid insulator in liquid nitrogen

Liquid nitrogen is expected to be used as dielectric material in high T/sub c/ superconducting power cable systems. In an electric power apparatus such as a termination for high T/sub c/ superconducting power cable, we need to consider not only radial electric stress but also axial electric stress. A particular concern is the dielectric breakdown at the surface of solid insulator in liquid nitrogen. We evaluated the surface discharge characteristics on the surface of the solid insulator in liquid nitrogen experimentally.