Superconducting High Voltage Cables (HV Cables)
Nexans provides superconducting HV cables for application in transmission and distribution level power grids. This cable type offers grid operators essential advantages in upgrading highly stressed grid sections of critical importance for the stability of power supply. Superconducting HVAC cables can provide greatly enhanced transmission capacities within existing routings wherever conventional grid expansion is impaired by right-of-way problems. Laying three single-phase cables in parallel requires a trench less than one meter in width. The environmental impact of such routings is marginal.
Power grid operators can rely on a qualified buriable system. Nexans superconducting HV cables are liquid nitrogen cooled and decoupled from the environment both electromagnetically and thermally. The solution comprises standard terminations for connecting superconducting cables to the normal conducting grid and joints for the realization of extended transmission lines with standardized elements. The Nexans HV product range includes superconducting cables for voltages up to 220 kV. Cables for higher voltage levels can be designed and furnished according to customer requirements.
Since 2008, the world’s first superconducting HV cable is in operation in a 138 kV transmission grid of Long Island Power Authority in the USA. The cable system of 600 meters length was supplied by Nexans and has a power transmission capacity of 574 MVA.
Nexans superconducting HV cables which are deployed for longer distance power transmission require cooling stations of a few square meters footprint to support their liquid nitrogen cooling system at suitable intervals.