SMES conductor selection: an engineering perspective

The authors discuss the engineering considerations driving the selection of a conductor concept for large-scale SMES (superconducting magnetic energy storage). There are five areas that require special attention: current diffusion effects, stability margin, AC losses, cooldown stress sustained by the conductor, and helium containment. From a magnet design perspective, there is a strong premium in SMES on utilizing conductors with as high a current as possible. It is difficult to scale up a particular monolithic design to achieve higher current. Overall magnet design issues are also more difficult to tackle with monolithic conductors. It is concluded that cable-in-conduit conductors are more attractive for large-scale SMES.>