SUPERCONDUCTING MAGNET AND ON-BOARD REFRIGERATION SYSTEM ON JAPANESE MAGLEV VEHICLE

Running tests on the Miyazaki test track are repeatedly carried out at speeds over 300 km/h using the MAGLEV vehicle, MLU002. The development of the MAGLEV system for the new test line has already started, and a new superconducting magnet for it has been manufactured. An on-board refrigerator is installed in the superconducting magnet to keep the liquid helium temperature without the loss of liquid helium. The helium gas produced when energizing or de-energizing the magnet is stored in on-board gas helium tanks temporarily. The on-board refrigerator is connected directly to the liquid helium tank of the magnet. Thus, the stored helium gas can be re-liquefied easily by the on-board refrigerator. In order to minimize the volume of the helium gas produced when energizing and de-energizing the magnet, power leads of the magnet, superconducting coils and persistent current switches have been improved. The energization and de-energization of the magnet can be finished in 1 to 2 minutes.