Improvement of Levitation Properties owing to High Magnetic Field in a Magnetic Levitation System with Magnetic Shielding Effect of HTS Bulk

We studied a magnetic levitation system incorporating a magnet, a high-temperature superconducting (HTS) bulk, and a ferromagnetic material. We changed a permanent magnet into an HTS magnet to improve the levitation properties of the system. Numerical analysis results showed that the maximum levitation force and maximum restoring force were 1550 and 338 g, respectively, which are 14 and 4.6 times larger than the corresponding values for a permanent magnet system. Next, we determined the levitation properties by changing the distance between the HTS magnet and the HTS bulk. Our data showed that as this distance increased, the peak levitation force decreased, while the restoring force increased. Finally, we tried to improve the levitation properties by increasing the magnetic field of the HTS magnet. The maximum levitation force and restoring force obtained were approximately 30 and 7.6 times larger, respectively, than the values obtained with the permanent magnet system. Thus, we succeeded in improving the levitation properties of the system.