SuperRail - World-first HTS cable to be installed on a commercial railway network in France

Abstract

Large scale oral sessionsInternational audienceThis paper presents the SuperRail project, launched in June 2022 and consisting in the development, the manufacturing and the installation of a high temperature superconducting HTS DC cable system. The objectives of the project are to reinforce the power supply of the Montparnasse railways station in Paris, to increase the traffic and to participate to the reduction of CO2 emission. The saturated underground in the centre of Paris does not allow to create new right of ways and only the HTS cable technology allows to carry the required power to railway tracks using the few available 100 mm ducts left. The cable system and the ancillary services have to answer to a load chart with a high level of requirements corresponding to the connection of a standard supply cell in a substation to a group of railways tracks in very constraints areas. The technologies developed have the potential to be reproduced in similar cases existing in large cities. In the case of SuperRail, two 80 m long 1.5 kV-3.5 kA HTS DC cables made of 2G conductors will be installed in parallel. They will need to sustain a 67 kA-200 ms short-circuit current. The cryogenic system to cool the HTS cables is specifically designed for this project. It is based on a Reverse Turbo-Brayton cycle providing cooling power of about 2 kW at 67 K. This system intends to ensure low maintenance during life cycle, high reliability and would be scalable for future application (unlimited to railway). Efforts are being done to reduce the losses in the 4 current leads, and to optimize the space required by the pipes for the circulation of the liquid nitrogen. In parallel, prospective studies are being carried out in order to find original solutions to replace the current leads by other systems integrating a part of the power converter and the transformer at cryogenic temperature. SuperRail is a landmark project, as it is the first time that a DC HTS cable system is installed on a commercially operated railway network