Superconducting magnets on Maglev trains vibrate due to harmonic ripples of electromagnetic flux generated by ground coils. Heat load caused by vibration in the magnet, made in 1990, amounted to several tens of watts in the electromagnetic vibration test. This was mainly because AC loss was induced in the helium vessel housing the superconducting coil, due to relative vibration between the aluminum thermal shield and the coil. The heat load caused by vibration should be strictly restricted to less than 4W due to limited cryogenic refrigeration capacity. The heat load has been tested using electromagnetic flux ripples for a superconducting magnet model of one coil which corresponds to 1/4 of an actual magnet. The flux ripples simulate the 6th harmonic of the actual ground levitation coil. Some ideas to reduce the heat load were tried for the magnet model, such as high resistance thermal radiation shield, high rigidity of vacuum vessel, high purity copper plating on the helium vessel. As a result, these ideas were effective, and the maximum heat load due to vibration was restrained to less than 4W per magnet for one coil magnet model.
