Design and analysis of a centripetal force type-magnetic bear-ing for a flywheel battery system

Flywheel battery, as a new energy storage device in recent years, it has the characteristics of high current charge -discharge capability, very short charging -discharging time, good environment adaptation, high energy conversion efficiency and long cycle life [1-2]. Flywheel battery technology is relatively mature after years of development, including the applications in electric vehicle systems. For a vehicular magnetically flywheel battery, the gyroscopic effect can be caused by the different driving conditions and the road conditions of the vehicle. Therefore, the flywheel battery has very strict requirements for bearings. The most popular magnetic bearings today are the magnetic bearings with cylinder structures, which have many industrial applications [3-4]. However, an inevitable unbalanced magnetic pull parallel he pull can be considered as a disturbance force) to the axis of the rotor will be produced when the rotor is deflected. The disturbance force and the resultant disturbance torque to the rotor will accelerate the gyroscopic effect and it is very bad for the stability control of the flywheel battery. In this paper, a novel centripetal force type magnetic bearing (CFT-MB) for a flywheel battery system is proposed.