The present disclosure relates to an energy cable comprising at least one cable core comprising an electric conductor, a crosslinked electrically insulating layer, and particles of a zeolite system comprising at least a first zeolite and a second zeolite placed in the cable core. The particles of the first zeolite are able to extract and absorb, very efficiently and irreversibly, the by-products deriving from the cross-linking reaction, so as to avoid space charge accumulation in the insulating material during cable lifespan. The particles of the second zeolite are able to absorb the water molecules that unexpectedly form from the dimerization/oligomerization and decomposition reaction of the crosslinking by-products upon their absorption on the first zeolite, so as to avoid the formation of water-trees in the insulating material. Moreover, the present invention relates to a method for extracting crosslinking by-products from a cross-linked electrically insulating layer of an energy cable core, which comprises manufacturing the energy cable core comprising particles of the above-said zeolite system, heating the energy cable core up to a temperature causing migration of the crosslinking by-products from the crosslinked electrically insulating layer; and then placing a metal screen around the energy cable core.

Provided is an intermediate connection system for an ultra-high-voltage direct-current (DC) power cable. Specifically, the present invention relates to an intermediate connection system, for an ultra-high-voltage DC power cable, which is capable of simultaneously preventing or minimizing electric field distortion, a decrease of DC dielectric strength, and a decrease of impulse breakdown strength due to the accumulation of space charges in an insulating layer of a cable and an insulating material of an intermediate connection part.

An electric cable has at least one semi-conductive layer obtained from a polymer composition having at least one polypropylene-based thermoplastic polymer material, at least one first antioxidant and at least one metal deactivator.

An alternating current (AC) power cable includes a conductor surrounded by at least an inner semiconductive layer including a first semiconductive composition, an insulation layer including a polymer composition, an outer semiconductive layer including a second semiconductive composition, and optionally a jacketing layer including a jacketing composition, in that order. The polymer composition of the insulation layer includes an unsaturated low density polyethylene (LDPE) copolymer of ethylene with one or more polyunsaturated comonomers and a crosslinking agent. The polymer composition of the insulation layer has a dielectric loss expressed as tan (50 Hz) of 12.010.sup.4 or less, when measured at 25 kV/mm and 130 C. according to Test for Tan measurements on 10 kV cables.

Semiconductive shield layers for power cable constructions are made from a composition that has: (A) A nonpolar, ethylene-based polymer having a density of greater than (>) 0.90 glee and a melt index of >20 g/10 min at 190 C./2.16 Kg; (B) A polar polymer consisting of ethylene and an unsaturated alkyl ester having 4 to 20 carbon atoms; (C) Acetylene carbon black; and (D) A curing agent; with the provisos that (1) the composition has a phase separated structure, and (2) the weight ratio of nonpolar polymer to polar polymer is from 0.25 to 4.

A cable for transmitting electricity may include a core including a first conductive material, a core shield surrounding the core, an insulation layer surrounding the core shield, the insulation layer comprising a material providing electrical insulating properties, an insulation shield surrounding the insulation layer; and at least one of the following at least partially surrounding the insulation shield: (a) a bedding layer including a first semi-conductive material, (b) a tape layer including a metallic tape intercalated with an insulating tape, and (c) a protection layer.

The present invention relates to a crosslinked polymer composition comprising a crosslinked polyolefin, wherein the polymer composition comprises, prior to crosslinking, a polyolefin and peroxide which is in an amount of less than 35 mmol OO-/kg polymer composition, characterized in that the crosslinked polymer composition has been in a direct contact with a semiconductive composition for 24 h at 70 C., and that the crosslinked polymer composition thereafter has an electrical DC-conductivity of 150 fS/m or less, wherein the electrical DC-conductivity is measured in accordance with DC conductivity method, as described under Determination methods, on a plaque of the crosslinked polymer composition at 70 C. and 30 kV/mm mean electric field from a non-degassed and 1 mm thick plaque sample of the crosslinked polymer composition; a layered structure, cable, e.g. a power cable, use of the crosslinked polymer composition and the structured layer, both, for producing a crosslinked power cable, e.g., a cross linked direct current (DC) power cable; and a process for producing a cable.

Provided is an intermediate connection system for an ultra-high-voltage direct-current (DC) power cable. Specifically, the present invention relates to an intermediate connection system, for an ultra-high-voltage DC power cable, which is capable of simultaneously preventing or minimizing electric field distortion, a decrease of DC dielectric strength, and a decrease of impulse breakdown strength due to the accumulation of space charges in an insulating layer of a cable and an insulating material of an intermediate connection part.

A tubular cable interconnect unit arranged on an outer periphery of a joint of a power cable, includes a tubular insulating tube, a non-ohmic resistor layer formed from a non-ohmic composition and provided on an inner peripheral surface of the insulating tube, and an inner semiconductive layer provided on the non-ohmic resistor layer, wherein the non-ohmic composition includes a base polymer including at least one of thermoplastic and rubber, and varistor grains having a non-ohmic characteristic in which a volume resistivity varies non-linearly with respect to an applied voltage, and the varistor grains have a maximum grain diameter of 30 m or less.

A fire resistant cable comprising a conductor and a sheath surrounding the conductor, the cable is characterized in further comprising: a bedding filler arranged between the conductor and the sheath and made of materials providing fire resistance; and, a tunnel filler arranged between the conductor and the sheath in the longitudinal direction of the cable, and having a melting point lower than the combustion point of the bedding filler.