Pull-up operation of an aluminum ring by utilizing ac ampere type magnetic levitation method

In general, the magnetic levitation (maglev) force on a nonmagnetic metal generated by an alternating magnetic field becomes a repulsive force; therefore, the nonmagnetic metal can only be pushed up from below by the repulsive force. In contrast, our prototype device succeeded in continuously pulling up a thin aluminum ring with a diameter of 120 mm by using ac electromagnetic force based on the ac ampere type maglev method we have proposed. This system operates just as if a permanent magnet attracts a magnetic material. This paper describes the configuration of the prototype device, derivation of exciting current conditions for generating the ac ampere force using finite element analysis and demonstration of steady levitation force and pull-up operation.