Improving kinetic energy storage for vehicles through the combination of rolling element and active magnetic bearings

The demand for short term energy storage providing high power for electric and hybrid-electric vehicles is increasing dramatically. Stationary flywheel energy storage systems (FESS) are established as uninterruptible power supply (UPS) and represent an emerging market. In contrast, mobile FESS are currently only used in few applications such as motor sports. To enable a wider use in personal and public transportation the lifespan of the flywheel's bearings needs to be increased significantly. This paper presents an alternative approach to extend the lifespan of the flywheel's bearings by using a combination of rolling element and active magnetic bearings (CREAMB).