Patent ID: 7608951

Claim:
An energy storage flywheel system, comprising: a shaft; a flywheel assembly mounted on the shaft; a plurality of magnetic bearing assemblies, each magnetic bearing assembly including a primary actuator coil and a secondary actuator coil, each actuator coil adapted to be selectively energized and deenergized, and configured, when energized, to rotationally mount the flywheel assembly in a non-contact manner; a plurality of secondary bearing assemblies, each secondary bearing assembly configured to selectively rotationally support the shaft; a secondary bearing actuator assembly coupled to one or more of the secondary bearing assemblies, the secondary bearing actuator assembly including a primary drive coil and a secondary drive coil, each secondary bearing actuator assembly drive coil adapted to selectively receive actuator control signals and operable, in response thereto, to cause the secondary bearing actuator assembly to move the one or more secondary bearing assemblies to one of (i) an engage position, in which each secondary bearing assembly rotationally supports the shaft, and (ii) a disengage position, in which each secondary bearing assembly does not rotationally supports the shaft; and a motor/generator coupled the energy storage flywheel and configured to operate in either a motor mode or a generate mode, the motor/generator including a rotor and a stator, the stator including a primary stator coil and a secondary stator coil.