High voltage system, particularly cable

Claim 1

High voltage cable with a particular first conductor of circular outer cross section and contour, and a second, tubular conductor coaxially arranged to the first conductor, the improvement comprising: inwardly projecting corrugation crests in the second conductor, having convex contour in a cross section plane, extending towards the tubular interior and having radius of curvature of Its convex contour which is substantially smaller than the radius of the inner conductor, the field strength at said corrugation crest and at said inner conductor being lower than 2 U/d loge D/d where d is the diameter of the first conductor, D is the average, mean or equivalent diameter of the outer tube, and U being the voltage between the conductors, so that the electric field strength immediately adjacent the corrugation crests of the second conductor is lower than the field strength immediately adjacent the first conductor, but higher than the field strength immediately adjacent a concavecylindrical surface for an equivalent outer uncorrugated tube having radius equal to the average or mean radius of the corrugated second conductor.