Abstract: A polymer composition includes a crosslinked polyolefin with improved DC electrical properties. Prior to crosslinking, the polymer composition includes a polyolefin and peroxide, in which the peroxide is in an amount of less than 35 mmol —O—O— per kilogram of the polymer composition. A cable can be surrounded by at least one layer including the polymer composition.

Abstract: A power capacitor unit including a casing, first and second layers of capacitor elements wherein the first layer of capacitor elements are stacked on the second layer of capacitor elements, a first busbar assembly connected to the capacitor elements of the first layer, a second busbar assembly connected to the capacitor elements of the second layer, wherein the first busbar assembly and the second busbar assembly are arranged between the first layer of capacitor elements and the second layer of capacitor elements, a heat conducting layer provided between the first busbar assembly and the second busbar assembly, wherein the heat conducting layer is in thermal contact with the casing, thereby conducting heat from the first busbar assembly and the second busbar assembly to the casing, and wherein the casing is electrically insulated from the first busbar assembly and the second busbar assembly.

Abstract: A cross-linked polymer composition includes a cross-linked polyolefin. Peroxide in an amount of less than 35 mmol —O—O—/kg polymer composition may be included in the polymer composition prior to crosslinking the polyolefin. Suitable polyolefins that can be cross-linked in the polymer composition include an unsaturated LDPE homopolymer and an unsaturated LDPE copolymer of ethylene with one or more comonomers. Such unsaturated LDPE polymer can contain vinyl groups, and the total amount of vinyl groups present in the unsaturated LDPE can be higher than 0.05/1000 carbon atoms. The cross-linked polymer composition can be used, for example, in producing a cross-linkable and cross-linked article such as a cross-linkable and cross-linked direct current (DC) or other type of power cable.

Abstract: A method in the manufacturing of an insulated electric high voltage DC termination or joint includes providing an insulated electric high voltage DC cable including a high voltage DC conductor, a polymer based insulation system surrounding the high voltage DC conductor, the polymer based insulation system including an insulation layer and a semiconducting layer surrounding the insulation layer, and a grounding layer surrounding the semiconducting layer; removing the grounding layer and the semiconducting layer in at least one end portion of the high voltage DC cable, mounting a field grading adapter or joint body in the at least one end portion of the high voltage DC cable; and subjecting the insulation layer of the polymer based insulation system in the at least one end portion of the high voltage DC cable for a heat treatment procedure, while being covered by the mounted field grading adapter or joint body.

Abstract: An electric power cable and a process for the production of the cable including a metal conductor and an electric insulation system surrounding the conductor coaxially and radially outwards of the conductor having improved electric properties. The insulation system includes an inner semi-conducting layer surrounded radially outwards by an insulation layer and wherein the insulation layer is surrounded radially outwards by an outer semi-conducting layer. The electric power cable further includes an inner water blocking material arranged in the conductor and/or to surround the conductor radially outwards and an outer water blocking material arranged radially outwards from the insulation system. An inner barrier layer is arranged as a diffusion hindering layer between the inner water blocking material and the insulation system and an outer barrier layer is arranged as a diffusion hindering layer between the insulation system and the outer water blocking material.

Abstract: A polymer composition includes a crosslinked polyolefin with improved DC electrical properties. Prior to crosslinking, the polymer composition includes a polyolefin and peroxide, in which the peroxide is in an amount of less than 35 mmol —O—O— per kilogram of the polymer composition. A cable can be surrounded by at least one layer including the polymer composition.

Abstract: A power capacitor unit including a casing, first and second layers of capacitor elements wherein the first layer of capacitor elements are stacked on the second layer of capacitor elements, a first busbar assembly connected to the capacitor elements of the first layer, a second busbar assembly connected to the capacitor elements of the second layer, wherein the first busbar assembly and the second busbar assembly are arranged between the first layer of capacitor elements and the second layer of capacitor elements, a heat conducting layer provided between the first busbar assembly and the second busbar assembly, wherein the heat conducting layer is in thermal contact with the casing, thereby conducting heat from the first busbar assembly and the second busbar assembly to the casing, and wherein the casing is electrically insulated from the first busbar assembly and the second busbar assembly.

Abstract: The present invention relates to a polymer composition comprising a polyolefin, peroxide and a sulphur containing antioxidant, wherein said peroxide is present in an amount which corresponds to X mmol —O—O—/kg polymer composition and said sulphur containing antioxidant is present in an amount which corresponds to Y mmol —OH/kg polymer composition, wherein Y1?Y?Y2, X?45 and 0.9*Y+m?X?n?k*Y, wherein Y1 is 0.50 and Y2 is 10, and m is 0.8, n is 70 and k is 4.7; and wherein said polymer composition has a melt flow rate (MFR) which is at least 1.7, and said polymer composition comprises less than 0.05% by weight (wt %) 2,4-Diphenyl-4-methyl-1-pentene; a crosslinked polymer composition, and use thereof, a power cable insulation, a power cable, useful in high voltage (HV DC) and extra high voltage (EHV DC) direct current applications, and a method for reducing electrical conductivity of a crosslinked polymer composition.

Abstract: The present invention relates to a crosslinked polymer composition, which is obtained by crosslinking a polymer composition, which polymer composition has a melt flow rate (MFR) of at least 1.7 and comprises a polyolefin, peroxide and sulphur containing antioxidant, characterized by that the crosslinked polymer composition has an Oxidation Induction Time, determined according to ASTM-D3895, ISO/CD 11357 and EN 728 using a Differential Scanning Calorimeter (DSC), which Oxidation Induction Time corresponds to Z minutes, and comprises an amount of peroxide by-products which corresponds to W ppm determined according to BTM2222 using HPLC, wherein Z1?Z?Z2, W1?W?W2, and W?p?270*Z, wherein Z1 is 0, Z2 is 60, W1 is 0 and W2 is 9500, and p is 18500; and use thereof, a power cable insulation and a power cable, useful in high voltage (HV) and extra high voltage (EHV) cable applications direct current (DC) applications.

Abstract: An electric power cable and a process for the production of the cable including a metal conductor and an electric insulation system surrounding the conductor coaxially and radially outwards of the conductor having improved electric properties. The insulation system includes an inner semi-conducting layer surrounded radially outwards by an insulation layer and wherein the insulation layer is surrounded radially outwards by an outer semi-conducting layer. The electric power cable further includes an inner water blocking material arranged in the conductor and/or to surround the conductor radially outwards and an outer water blocking material arranged radially outwards from the insulation system. An inner barrier layer is arranged as a diffusion hindering layer between the inner water blocking material and the insulation system and an outer barrier layer is arranged as a diffusion hindering layer between the insulation system and the outer water blocking material.

Abstract: A method in the manufacturing of an insulated electric high voltage DC termination or joint includes the steps of providing an insulated electric high voltage DC cable including an inner conductor; a polymer based insulation system, the polymer based insulation system comprising an insulation layer and a semiconducting layer; and an outer grounding layer; removing the grounding layer and the semiconducting layer in at least one end portion of the high voltage DC cable, thereby exposing the insulation layer in the at least one end portion of the high voltage DC cable; covering the insulation layer of the polymer based insulation system in the at least one end portion of the high voltage DC cable by a cover impermeable to at least one substance present in the insulation layer of the polymer based insulation system in the at least one end portion of the high voltage DC cable in a non-homogenous distribution; subjecting the insulation layer of the polymer based insulation system in the at least one end portion of

Abstract: A method in the manufacturing of an insulated electric high voltage DC termination or joint includes providing an insulated electric high voltage DC cable including a high voltage DC conductor, a polymer based insulation system surrounding the high voltage DC conductor, the polymer based insulation system including an insulation layer and a semiconducting layer surrounding the insulation layer, and a grounding layer surrounding the semiconducting layer, removing the grounding layer and the semiconducting layer in at least one end portion of the high voltage DC cable, thereby exposing the insulation layer of the polymer based insulation system in the at least one end portion of the high voltage DC cable, mounting a field grading adapter or joint body in the at least one end portion of the high voltage DC cable, thereby covering the insulation layer of the polymer based insulation system in the at least one end portion of the high voltage DC cable, the field grading adapter or joint body being part of the high

Abstract: An apparatus for enclosing a medium and/or high voltage unit connectable to an electric power system. The unit includes one or a plurality of electrical components and generates heat as a by-product during operation. The apparatus includes a housing including a main chamber housing a seat for holding the unit. The main chamber is arranged to house the unit. The housing includes at least one gas exit opening at an upper part of the housing and at least one gas entry opening. The housing includes a sound-absorptive gas exit chamber provided with the at least one gas exit opening. The housing includes a sound-absorptive gas entry chamber provided with the at least one gas entry opening. A first heat convection path is provided inside the housing between the at least one gas entry opening and the at least one gas exit opening, via the gas entry chamber, via the main chamber and via the gas exit chamber, in order to provide cooling.

Abstract: The present invention relates to a crosslinked polymer composition, which is obtained by crosslinking a polymer composition, which polymer composition has a melt flow rate (MFR) of at least 1.7 and comprises a polyolefin, peroxide and sulphur containing antioxidant, characterised by that the crosslinked polymer composition has an Oxidation Induction Time, determined according to ASTM-D3895, ISO/CD 11357 and EN 728 using a Differential Scanning Calorimeter (DSC), which Oxidation Induction Time corresponds to Z minutes, and comprises an amount of peroxide by-products which corresponds to W ppm determined according to BTM2222 using HPLC, wherein Z1?Z?Z2, W1?W?W2, and W?p?270*Z, wherein Z1 is 0 , Z2 is 60, W1 is 0 and W2 is 9500, and p is 18500; and use thereof, a power cable insulation and a power cable, useful in high voltage (HV) and extra high voltage (EHV) cable applications direct current (DC) applications.

Abstract: The present invention relates to a polymer composition comprising a polyolefin, peroxide and a sulphur containing antioxidant, wherein said peroxide is present in an amount which corresponds to X mmol -0-0-/kg polymer composition and said sulphur containing antioxidant is present in an amount which corresponds to Y mmol —OH/kg polymer composition, wherein Y1?Y?Y2, X?45 and 0.9*Y+m?X?n?k*Y, wherein Y1 is 0.50 and Y2 is 10, and m is 0.8, n is 70 and k is 4.7; and wherein said polymer composition has a melt flow rate (MFR) which is at least 1.7, and said polymer composition comprises less than 0.05% by weight (wt %) 2,4-Diphenyl-4-methyl-1-pentene; a crosslinked polymer composition, and use thereof, a power cable insulation, a power cable, useful in high voltage (HV DC) and extra high voltage (EHV DC) direct current applications, and a method for reducing electrical conductivity of a crosslinked polymer composition.

Abstract: An apparatus for enclosing a medium and/or high voltage unit connectable to an electric power system. The unit includes one or a plurality of electrical components and generates heat as a by-product during operation. The apparatus includes a housing including a main chamber housing a seat for holding the unit. The main chamber is arranged to house the unit. The housing includes at least one gas exit opening at an upper part of the housing and at least one gas entry opening. The housing includes a sound-absorptive gas exit chamber provided with the at least one gas exit opening. The housing includes a sound-absorptive gas entry chamber provided with the at least one gas entry opening. A first free heat convection path is provided inside the housing between the at least one gas entry opening and the at least one gas exit opening, via the gas entry chamber, via the main chamber and via the gas exit chamber, in order to provide cooling.

Abstract: A method in the manufacturing of an insulated electric high voltage DC termination or joint includes the steps of providing an insulated electric high voltage DC cable including an inner conductor; a polymer based insulation system, the polymer based insulation system comprising an insulation layer and a semiconducting layer; and an outer grounding layer; removing the grounding layer and the semiconducting layer in at least one end portion of the high voltage DC cable, thereby exposing the insulation layer in the at least one end portion of the high voltage DC cable; covering the insulation layer of the polymer based insulation system in the at least one end portion of the high voltage DC cable by a cover impermeable to at least one substance present in the insulation layer of the polymer based insulation system in the at least one end portion of the high voltage DC cable in a non-homogenous distribution; subjecting the insulation layer of the polymer based insulation system in the at least one end portion of

Abstract: A method for providing an insulated electric high voltage DC cable or a high voltage DC termination or joint. A polymer based insulation system including a compounded polymer composition is provided. The polymer based insulation system is subsequently exposed to a heat treatment procedure while the outer surface of the polymer based insulation system is covered by a cover impermeable to a substance present in the polymer based insulation system in a non-homogenous distribution, thereby equalizing the concentration of the substance in the polymer based insulation system.

Abstract: A polymer composition with improved DC electrical properties and a cable surrounded by at least one layer comprising the polymer composition are provided.

Abstract: An extruded high voltage cable including a conductor with at least three concentric layers of helically wound metal wires, an extruded inner conducting layer surrounding the conductor, and an extruded electrical insulation arranged outside the inner conducting layer. The two outermost layers of the conductor have the same lay direction.