The BEST PATHS Project on $MgB_2$ Superconducting Cables for Very High Power Transmission

BEST PATHS (acronym for “BEyond State-of-the-art Technologies for rePowering Ac corridors and multi-Terminal HVDC Systems”) is a collaborative project within the FP7 framework of the European Commission that includes an $MgB_2$ -based power transmission line among its five constituent demonstrators. Led by Nexans and bringing together transmission operators, industry and research organizations, this demonstrator aims at validating the novel $MgB_2$ technology for very high power transfer (gigawatt range). The project foresees the development of a monopole cable system operating in helium gas in the range of 5-10 kA/200-320 kV, corresponding to a transmitted power from 1 to 3.2 GW. The main research and demonstration activities that will be pursued over the four-year project duration are: 1) development and manufacturing of $MgB_2$ wires and of the cable conductor; 2) design and manufacturing of the HVDC electrical insulation of the cable; 3) optimization of the required cryogenic system; 4) electromagnetic field analysis; 5) design and construction of a prototype electrical feeding system, including terminations and connectors; 6) testing of the demonstrator; 7) study of grid connection procedures and integration of a superconducting link into a transmission grid; and finally, 8) a socio-economic analysis of the $MgB_2$ power transmission system. CIGRE recommendations will be used to take into account the established international practices, and guidance will be given on newly addressed technical aspects. An overview of the project is presented in this paper, including the main tasks and challenges ahead, as well as the partners and their roles.