Interdisciplinary Graduate School of Engineering Sciences, Kyushu University
Abstract
Electrical insulators are important components in a superconducting magnet. In contrast with the superconducting power cable, insulating materials to be used for the magnet in a large fusion device must have excellent electrical performance and durability for a long period of about 40 years under high mechanical stresses and cryogenic temperature. In the present paper, the problem which may become important for the design of an electrical insulation of the magnet is surveyed and experimental results on the influence of mechanical stresses on the electrical insulation performance of PET (polyethylene telephthalate) and FRP (fiberglass reinforced plastics ; epoxy glass cloth) are reported. Some characteristics are newly found on the relationship between breakdown field strength and mechanical properties of PET and FRP
