Magnetic Levitation Flywheel Energy Storage System With Motor-Flywheel Integration

This article proposed a compact and highly efficient flywheel energy storage system (FESS). Single coreless stator and double rotor structures are used to eliminate the idling loss caused by the flux of permanent magnet (PM) machines. A novel compact magnetic bearing is proposed to eliminate the friction loss during high-speed operation. First, the structure and working principle of the FESS are described in detail. Then, the topology of the magnetic bearing is introduced, and its magnetic circuit model is built and analyzed. Finally, the electromagnetic performance of the PM machine is estimated by analytical method and effectively verified by finite element method.