A 300 Wh class flywheel energy storage system using high Tc superconductor bearings (HTC SFES) has been under development. The HTC SFES running in a vacuum chamber mainly consists of a composite flywheel rotor, superconductor bearings, a motor/generator and its controller. The present HTC SFES was designed to have maximum operating speed of 33,000 rpm, which is way above two rigid body mode critical speeds of 638 and 1311 rpm. It has been experimentally verified that the system can run smoothly up to 20,000 rpm. The coreless Halbach magnet array motor & generator has also been proven to be effective on transferring electrical energy to the rotating composite flywheel in kinetic form. Rotor-dynamic analyses were performed and compared with experimental results of HTC SFES with a horizontal axle.
- Flywheel energy storage system
- Magnetic levitation
- Rotor-dynamic analysis
- Superconductor bearing