High voltage electric power cable with thermal expansion accommodation

摘要

The insulation shield in a power cable having thick polymeric insulation is constructed of a metallic layer radially spaced from but in electrical communication with an inner semiconducting layer by an intervening helical wrap of a semiconducting or high dielectric constant longitudinal structurally resiliently compressible substantially shape recoverable element. Various elements are described, both hollow and solid, with and without one flat longitudinal surface, and of both monolithic plastic and composite plastic and metal construction.