Abstract: The invention is a flywheel rotor that includes a number of adjacent laminations, stacked one on top of another, where each of the laminations has the same shape and is rotationally symmetric around a center axis, and where the shape is substantially circular and includes a plurality of protrusions exterior to the circumference, and each of the laminations includes at least one hole for a fastening bolt to pass through. The invention typically includes an endplate at each end of stack of laminations. One of the two endplates may attach to a stubshaft.

Abstract: The invention is a flywheel rotor that includes a number of adjacent laminations, stacked one on top of another, where each of the laminations has the same shape and is rotationally symmetric around a center axis, and where the shape is substantially circular and includes a plurality of protrusions exterior to the circumference, and each of the laminations includes at least one hole for a fastening bolt to pass through. The invention typically includes an endplate at each end of stack of laminations. One of the two endplates may attach to a stubshaft.

Abstract: The invention is a flywheel rotor that includes a number of adjacent laminations, stacked one on top of another, where each of the laminations has the same shape and is rotationally symmetric around a center axis, and where the shape is substantially circular and includes a plurality of protrusions on the circumference, and each of the laminations includes at least one hole for at fastening bolts to pass through. The invention typically includes an endplate at each end of stack of laminations and one of the two endplates attaches to a stubshaft.

Abstract: A flywheel apparatus that magnetically unloads a top rotor bearing is described. The apparatus includes a flywheel housing, a rotor with a vertical axis of rotation that includes a magnetic material, a magnet configured to apply a desired upward off-loading force along the vertical axis of rotation, an upper bearing connected to an upper shaft of the rotor, and a bearing housing disposed between the upper bearing and the flywheel housing that substantially prevents downward axial motion of the upper bearing. The magnet includes an electromagnet. A force sensor is used to measure a force on the upper bearing which is provided as input to a controller that updates the current to the electromagnet. The rotor is maintained in a fixed axial position and a spring disposed below a lower bearing absorbs axial dimension growth of the rotor.

Abstract: The invention is an augmented energy storage system that includes an energy storage subsystem that stores and supplies energy to an electric grid, a load bank that dissipates energy, a power control system that controls the flow of energy into and out of the energy storage subsystem and into the load bank, and an inverter that converts DC current to AC current used by the grid.

Abstract: The invention is a flywheel rotor that includes a number of adjacent laminations, stacked one on top of another, where each of the laminations has the same shape and is rotationally symmetric around a center axis, and where the shape is substantially circular and includes a plurality of protrusions on the circumference, and each of the laminations includes at least one hole for at fastening bolts to pass through. The invention typically includes an endplate at each end of stack of laminations and one of the two endplates attaches to a stubshaft.

Abstract: A number of flywheel units are arranged in a geometric pattern. Each of the flywheel units is enclosed in a containment unit. The containment unit includes a cylindrical tube, a cover, a bottom support, resting on the ground, on which the containment unit is mounted, and a fill medium surrounding each containment unit. The containment unit may also include a horizontal plate, mounted to the base of tube, which extends outward or radially from the base of tube a pre-determined length. In this case, the fill medium rests directly on top of the portion of the plate that extends outward from tube.

Abstract: A flywheel energy storage system includes a flywheel housing that encloses a flywheel rotor, a motor/alternator, and a power electronics unit. The power electronics unit includes a power electronics housing directly mounted on the flywheel housing, and one or more power electronic circuits enclosed by the power electronics housing. The direct mounting of the power electronics housing on the flywheel housing enables thermal distribution for passive cooling purposes. The design of the flywheel energy storage system also reduces the vibrational forces imparted by the power electronics housing on the flywheel housing.

Abstract: A flywheel device includes structures allowing the flywheel system to be assembled offsite, transported safely, and installed with relatively few steps. The flywheel includes a rotor and a housing enclosing the rotor, where the housing includes a bottom plate, a top plate and side walls. The bottom plate and the top plate each includes a hole aligned with the center axis of the rotor. The flywheel also includes multiple bearing housings substantially covering the holes of the bottom plate and the top plate that are aligned to the center axis of the rotor. The flywheel also includes posts that physically contact the primary rotational mass of the rotor to prevent motion of the rotor during transport of the flywheel system. Some or all of these posts may be repositioned or removed during installation so that the rotor can spin freely.

Abstract: A flywheel device includes an enclosure that surrounds an interior chamber that includes a rotor, which during normal operation is maintained in a vacuum state and spinning, the enclosure includes a first opening, and a valve that attaches to the enclosure, configured to enable, when actuated, ambient air to flow from the exterior of the enclosure into the chamber through the first opening, thus allowing the internal air pressure to rapidly approach ambient air pressure and thereby increase the air drag which acts as a brake on the spinning rotor.

Abstract: Embodiments of the subject invention are directed to a flywheel rotor that includes two or more sub-rotors stacked one on top of another, in which each sub-rotor is rotationally symmetric and disk shaped, where the axial centers of each sub-rotor in the stack are rotationally aligned, and each sub-rotor has an upper and a lower journal that extends outward from the origin of the center section of the primary rotational mass of the sub-rotor. Each pair of adjacent sub-rotors in the stack has a lower journal of an upper sub-rotor that is disposed above an upper journal of a lower sub-rotor. Also, there is a joining mechanism between each pair of adjacent sub-rotors that fixedly connects the lower journal of the upper sub-rotor to the upper journal of the lower sub-rotor.

Abstract: A flywheel apparatus that magnetically unloads a top rotor bearing is described. The apparatus includes a flywheel housing, a rotor with a vertical axis of rotation that includes a magnetic material, a magnet configured to apply a desired upward off-loading force along the vertical axis of rotation, an upper bearing connected to an upper shaft of the rotor, and a bearing housing disposed between the upper bearing and the flywheel housing that substantially prevents downward axial motion of the upper bearing. The magnet includes an electromagnet. A force sensor is used to measure a force on the upper bearing which is provided as input to a controller that updates the current to the electromagnet. The rotor is maintained in a fixed axial position and a spring disposed below a lower bearing absorbs axial dimension growth of the rotor.

Abstract: A flywheel energy storage system includes a flywheel housing that encloses a flywheel rotor, a motor/alternator, and a power electronics unit. The power electronics unit includes a power electronics housing directly mounted on the flywheel housing, and one or more power electronic circuits enclosed by the power electronics housing. The direct mounting of the power electronics housing on the flywheel housing enables thermal distribution for passive cooling purposes. The design of the flywheel energy storage system also reduces the vibrational forces imparted by the power electronics housing on the flywheel housing.

Abstract: Embodiments of the subject invention are directed to a flywheel rotor that includes two or more sub-rotors stacked one on top of another, in which each sub-rotor is rotationally symmetric and disk shaped, where the axial centers of each sub-rotor in the stack are rotationally aligned, and each sub-rotor has an upper and a lower journal that extends outward from the origin of the center section of the primary rotational mass of the sub-rotor. Each pair of adjacent sub-rotors in the stack has a lower journal of an upper sub-rotor that is disposed above an upper journal of a lower sub-rotor. Also, there is a joining mechanism between each pair of adjacent sub-rotors that fixedly connects the lower journal of the upper sub-rotor to the upper journal of the lower sub-rotor.

Abstract: A number of flywheel units are arranged in a geometric pattern. Each of the flywheel units is enclosed in a containment unit. The containment unit includes a cylindrical tube, a cover, a bottom support, resting on the ground, on which the containment unit is mounted, and a fill medium surrounding each containment unit. The containment unit may also include a horizontal plate, mounted to the base of tube, which extends outward or radially from the base of tube a pre-determined length. In this case, the fill medium rests directly on top of the portion of the plate that extends outward from tube.

Abstract: A flywheel device includes structures allowing the flywheel system to be assembled offsite, transported safely, and installed with relatively few steps. The flywheel includes a rotor and a housing enclosing the rotor, where the housing includes a bottom plate, a top plate and side walls. The bottom plate and the top plate each includes a hole aligned with the center axis of the rotor. The flywheel also includes multiple bearing housings substantially covering the holes of the bottom plate and the top plate that are aligned to the center axis of the rotor. The flywheel also includes posts that physically contact the primary rotational mass of the rotor to prevent motion of the rotor during transport of the flywheel system. Some or all of these posts may be repositioned or removed during installation so that the rotor can spin freely.