The Central Japan Railway Company (JR Central) has successfully used American Superconductor Corporation’s (AMSC) high temperature superconductor (HTS) wire in a prototype electromagnetic coil designed for use as the lifting component in its magnetically levitated (‘Maglev’) train system.
The Maglev train itself is the vehicle being considered for Japan’s Chuo Shinkansen – an alternate rail route connecting Tokyo to Osaka.
JR Central designed the HTS maglev coil and chose AMSC’s wire for the project for its high current-carrying capability. To optimise the current density, AMSC provided bare wire without the standard strengthening process of stainless steel lamination that is used on AMSC’s wire for most other applications.
Final development and fabrication of the coil was completed by Toshiba Corporation using a new HTS coil manufacturing technique. Recent improvements in the coil winding techniques made it possible to maximize the current density of the wire while meeting vibration requirements for the Maglev train.
Importantly, JR Central also reported that its HTS Maglev coils can be cooled by means of direct thermal contact with refrigeration systems and do not require the liquid helium cooling needed for the LTS coils.
JR Central and Japan’s Railway Technical Research Institute’s (RTRI) current Maglev train system, which today must rely on low temperature superconductor (LTS) electromagnets, recently set a world speed record of 581 kilometre per hour (360 miles per hour) for the highest speed attained by a manned superconducting magnetically levitating train while “flying” about 10 centimetres (4 inches) above its ‘track.’
Switching from LTS to HTS electromagnets will reduce both capital and operating costs for the Maglev train system.
The total potential HTS wire requirement for a full, commercial Maglev train system is expected to exceed 100 million metres.
A full description of other technical developments relating to the Maglev train can be found on the JR Central site.