Permanent magnet thrust bearings for flywheel energy storage systems: Analytical, numerical, and experimental comparisons

Quantitative Reliability Assessment of Ball Bearings versus Active Magnetic Bearings for Flywheel Energy Storage Systems

Design and Analysis of Novel Bearingless Permanent Magnet Synchronous Motor for Flywheel Energy Storage System

To effectively simplify system structure and improve power density and efficiency, a design for a motor/generator suitable for flywheel energy storage system (FESS) is proposed. The machine is an outer-rotor and coreless-stator-type bearingless permanent magnet synchronous motor (BPMSM) with a Halbach array. Firstly, the operation principle of the outer-rotor BPMSM is described. Then, the struc...

Flywheel energy and power storage systems

For ages flywheels have been used to achieve smooth operation of machines. The early models where purely mechanical consisting of only a stone wheel attached to an axle. Nowadays flywheels are complex constructions where energy is stored mechanically and transferred to and from the flywheel by an integrated motor/generator. The stone wheel has been replaced by a steel or composite rotor and mag...

Study of Permanent Magnet Bearings and their Stiffness

A typical passive magnetic bearing has been modeled and analyzed for its performance characteristics. The magnetic bearing studied in this work comprised of a Shaft, inner magnets sleeved over the shaft, and outer magnetic rings. A detailed analysis has been perform on the force exerted by a permanent magnet on the shaft nurture to restore the shaft to its equilibrium position when an eccentric...

Design, Modeling and Control of Magnetic Bearings for a Ring-Type Flywheel Energy Storage System

This study is concerned with the magnetic force models of magnetic bearing in a flywheel energy storage system (FESS). The magnetic bearing is of hybrid type, with axial passive magnetic bearing (PMB) and radial hybrid magnetic bearing (HMB). For the PMB, a pair of ring-type Halbach arrays of permanent magnets are arranged vertically to support the rotor weight. For the HMB, a set of ring-type ...