Three-dimensional vibration of the rotor in the HTSC-permanent magnet flywheel system

The three dimensional vibration of the rotor in the HTSC-permanent magnet f lywheel system is studied. The magnetic levitation using pining force of th e HTSC bulk material has an advantage to achieve stable levitation without control. However the transient characteristics of the levitation is not cle arly understood. We have developed the flywheel system which can revolve up to 12,000rpm, and the three dimensional vibration of the rotor are measure d with laser displacement sensors. The vibration of the rotor around the me chanical resonance frequency is investigated. The rotor shows both columnar and conical behavior in the mechanical resonant state.