We are promoting material research on high-temperature superconducting tapes and design, trial production, and characteristic evaluation of high-temperature superconducting feeder cables with the aim of applying high-temperature superconducting cables to feeders of DC railways. The introduction of superconducting feeder cables is expected to improve regenerative efficiency, reduce power loss, level the load between substitutions, and consolidate substitutions by suppressing voltage drops.
In order to introduce a superconducting feeder cable between substitutions, it is necessary to realize a kilometer-class superconducting feeder cable. Due to restrictions of laws such as the Road Traffic Act, a superconducting feeder cable sheathed in a heat insulating pipe can only be transported up to a length of about 500 m. Therefore, in order to realize a kilometer-class superconducting feeder cable, on-site joint technique between superconducting feeder cables is required. In this paper, we clarify the electrical and mechanical characteristics of the joint part and introduce an examination on joint methods of superconducting tapes by the finite element method and joint experiments.

Keywords: superconducting feeder cable, joint, current test