The superconducting flywheel energy storage systems (FESS) can stabilize the fluctuation of the output from solar photovoltaic power generation systems. The FESS has been developed as a joint project of five enterprises subsidized by the New Energy and Industrial Technology Development Organization. Four key technology of the FESS are the magnetic fluid seal (MFS) technology for vacuum seal using a multi-material shaft, the active magnetic bearing (AMB) technology for non-contact levitated support, the dynamic break resistor (DBR) technology for allowing storage energy to be consumed as heat energy, and the touch-down bearing (TDB) technology for the safety device in case of the superconducting magnetic bearing’s failure. In this paper, the principles and features of those technologies are explained, and the validity of the design is also presented.
