Three-Core to Three Single Core HV or EHV Submarine Power Cable System

A submarine power cable installation comprising:

• a HV or EHV submarine power cable system including,
• a three-core submarine power cable including three stranded power cores, each including a respective conductor and an insulation system arranged around the conductor, including an inner semiconducting layer, and insulation layer including a first polymeric material, and an outer semiconducting layer,
• three single core submarine power cables, each including a respective conductor and insulation system arranged around the conductor, including an inner semiconductor layer, an insulation layer including the first polymeric material, and an outer semiconducting layer, and
• a rigid joint connecting each power core of the three-core submarine power cable to a respective one of the single core submarine power cables,
• wherein the three-core submarine power cable lays offshore,
• wherein the rigid joint is installed offshore before landfall of the three single core submarine power cables, wherein a first section of each three single core submarine power cable extends under water, and
• wherein a second section of each three single core submarine power cable extends on land.

A method of operating a submarine power cable installation, having a HV or EHV submarine power cable system inducing,

• a three-core submarine power cable including three standard power cores, each including a respective conductor and an insulation system arranged around the conductor, including an inner semiconducting layer, an insulation layer including a first polymeric material, and an outer semiconductor layer,
• three single core submarine power cables, each including a respective conductor and insulation system arranged around the conductor, including an inner semiconductor layer, an insulation layer including the first polymeric material, and an outer semiconductor layer, and
• a rigid joint connecting each power core of the three-core submarine power cable to a respective one of the single core submarine power cables, wherein the three-core submarine power cable lays offshore,
• wherein the rigid joint is installed offshore before landfall of the three single core submarine power cables, wherein a first section of each three single core submarine power cable extends under water, and
• wherein a second section of each three single core submarine power cable extends on land, the method comprising increasing the current rating of the HV or EHV submarine power cable system based on reduced heat losses in the three single core submarine power cables.