An insulation system for jointing of high voltage conductors has an inner layer made of a crosslinked first polymeric semiconducting material, an intermediate insulating layer made of a thermoplastic polymeric insulating material, and an outer layer made of a second polymeric semiconducting material. The insulation system is adapted for surrounding the electric conductor joint.

An insulation system for jointing of high voltage conductors has an inner layer made of a crosslinked first polymeric semiconducting material, an intermediate insulating layer made of a thermoplastic polymeric insulating material, and an outer layer made of a second polymeric semiconducting material. The insulation system is adapted for surrounding the electric conductor joint.

The present disclosure relates to a power cable joint system capable of minimizing expansion, deformation or damage of a metal sheath restoration layer, which is formed of a material such as lead sheath, due to internal expansion due to heat generated in an intermediate connection part of the power cable joint system.

The present disclosure relates to a power cable joint system capable of minimizing expansion, deformation or damage of a metal sheath restoration layer, which is formed of a material such as lead sheath, due to internal expansion due to heat generated in an intermediate connection part of the power cable joint system.

An ultra-high-voltage DC power cable system capable of simultaneously preventing or minimizing electric field distortion, a reduction of DC dielectric strength, and a reduction 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 method of building a joint insulation of a power cable joint including a conductor joint connecting a first conductor of a first cable length to a second conductor of second cable length, the method including: a) winding a first electrically insulating tape around an inner semiconducting layer that covers the conductor joint so that the first electrically insulating tape connects a first cable length insulation layer of the first cable length to a second cable length insulation layer of the second cable length, to form an inner insulation layer of the joint insulation, and b) winding a second electrically insulating tape around the inner insulation layer, so that the second electrically insulating tape connects the first cable length insulation layer to the second cable length insulation layer, to form an outer insulation layer of the joint insulation, wherein the first electrically insulating tape has a higher peroxide content than the second electrically insulating tape, and c) crosslinking the joint insulation.

The present disclosure relates to a power cable and an intermediate connection structure, for connection thereof, which is capable of preventing the concentration of stress on a soldered part, which is configured to join a metal sheath of the power cable and a metal sheath restoration layer of the intermediate connection structure while ensuring airtight or watertight sealing therebetween, preventing deformation of or damage to the soldered part due to stress applied thereto, and minimizing thermal history in the power cable during the formation of the soldered part.

The present disclosure relates to a power cable and an intermediate connection structure, for connection thereof, which is capable of preventing the concentration of stress on a soldered part, which is configured to join a metal sheath of the power cable and a metal sheath restoration layer of the intermediate connection structure while ensuring airtight or watertight sealing therebetween, preventing deformation of or damage to the soldered part due to stress applied thereto, and minimizing thermal history in the power cable during the formation of the soldered part.

An insulating tape for coating a connection portion of a power cable is unlikely to cause local cracking to a fused part even when a highly hydrophilic polyethylene is used. This insulating tape is formed of a resin material including a polyethylene which is at least partially modified by a molecule capable of imparting hydrophilicity; an antioxidant; and a cross-linking agent. The antioxidant has a molecular weight of not less than 190 but less than 1,050. The contained amount of the antioxidant is 0.05-0.8 parts by mass with respect to 100 parts by mass of the polyethylene. The insulating tape has a thickness of 50-250 μm. In addition, this power cable 1 is provided with a connection structure that has a connection portion formed by conductively connecting ends of multiple power cables where respective conductors are exposed. An insulating coating is formed on the exterior surface of the connection portion by at least winding and cross linking the aforementioned insulating tape around the circumference of the connection portion.

An insulating resin composition that allows a reduction in the amount of spatial electric charges accumulated in an insulating layer, whereby dielectric breakdown is less likely to occur. This insulating resin composition 1 contains at least an antioxidant and a base resin including an unmodified polyolefin resin and a modified polyolefin resin modified by a molecule having a polar group. The modified polyolefin resin is modified by at least one selected from unsaturated dicarboxylic anhydride derivatives, unsaturated dicarboxylic anhydrides, and unsaturated dicarboxylic acids, which are each a molecule having a polar group. The base resin has a so-called island-in-sea structure in which a second phase 12 containing the modified polyolefin resin is present in a first phase 11 containing the unmodified polyolefin resin. The second phase has an average diameter of 2 μm or less.