Provided is a power cable, particularly, an ultra-high voltage underground or submarine cable for long-distance direct-current transmission. Specifically, the present invention relates to a power cable which includes an insulating layer of high dielectric strength, is capable of uniformly and effectively alleviating an electric field applied to the insulating layer, is particularly structurally stable, has high flexibility, and is capable of suppressing partial discharge, dielectric breakdown, etc. of the insulating layer, thereby increasing the lifespan and productivity of the cable.

Provided is a power cable, particularly, an ultra-high voltage underground or submarine cable for long-distance direct-current transmission. Specifically, the present invention relates to a power cable which includes an insulating layer of high dielectric strength, is capable of uniformly and effectively alleviating an electric field applied to the insulating layer, is particularly structurally stable, has high flexibility, and is capable of suppressing partial discharge, dielectric breakdown, etc. of the insulating layer, thereby increasing the lifespan and productivity of the cable.

A power cable includes a conductor, an inner semi-conductive layer covering the conductor, an insulating layer covering the inner semi-conductive layer and impregnated with insulating oil, an outer semi-conductive layer covering the insulating layer, a metal sheath layer covering the outer semi-conductive layer, and a cable protection layer covering the metal sheath layer. A minimum thickness t1 of a certain cross section of the metal sheath layer is less than or equal to 90% of a maximum thickness t2 thereof.

A power cable includes a conductor, an inner semi-conductive layer covering the conductor, an insulating layer covering the inner semi-conductive layer and impregnated with insulating oil, an outer semi-conductive layer covering the insulating layer, a metal sheath layer covering the outer semi-conductive layer, and a cable protection layer covering the metal sheath layer. A minimum thickness t1 of a certain cross section of the metal sheath layer is less than or equal to 90% of a maximum thickness t2 thereof.

Cables having a conductor with a polymeric covering layer and a non-extruded coating layer made of a material based on a liquid composition including a polymer resin and a fatty acid amide. Methods of making cables are also provided.

Cables having a conductor with a polymeric covering layer and a non-extruded coating layer made of a material based on a liquid composition including a polymer resin and a fatty acid amide. Methods of making cables are also provided.

Provided is a power cable, particularly, an ultra-high voltage underground or submarine cable for long-distance direct-current transmission. Specifically, the present invention relates to a power cable which includes an insulating layer of high dielectric strength, is capable of uniformly and effectively alleviating an electric field applied to the insulating layer, is particularly structurally stable, has high flexibility, and is capable of suppressing partial discharge, dielectric breakdown, etc. of the insulating layer, thereby increasing the lifespan and productivity of the cable.

Provided is a power cable, particularly, an ultra-high voltage underground or submarine cable for long-distance direct-current transmission. Specifically, the present invention relates to a power cable which includes an insulating layer of high dielectric strength, is capable of uniformly and effectively alleviating an electric field applied to the insulating layer, is particularly structurally stable, has high flexibility, and is capable of suppressing partial discharge, dielectric breakdown, etc. of the insulating layer, thereby increasing the lifespan and productivity of the cable.

There is provided an insulated electric wire comprising a conductor wire coated by an insulating film, in which the insulating film contains 5 to 20% by mass of a low boiling point component having a boiling point of less than 300° C. under normal pressure. The insulating film preferably has a thickness of 40 to 65 μm. The conductor wire preferably has a cross-sectional shape in a rectangular shape or a square shape.

A system and method are described for regulating water concentration in a dielectric fluid. The system can comprise electrodes capable of applying an electric field across the dielectric fluid, thereby causing charge carriers and water included in the charge carriers to move toward a respective electrode. The system further includes a trap positioned near the electrodes and comprising a water absorbing material capable of trapping water, thereby reducing the concentration of water in the dielectric fluid. It is also possible to measure properties of the dielectric fluid and use such measurements to control the water-trapping process.