Integrated motor/generator/flywheel utilizing a solid steel rotor

DETAILED DESCRIPTION These and other objects of the invention are accomplished in accordance with the principles of the invention by providing various flywheel energy conversion devices.
The preferred embodiments include a brushless generator having its armature coils located in an air gap in place of the traditional ferrous armature core.
The energy storage devices also include at least one stationary annular field coil that, in conjunction with a rotating toothed-rotor and a stationary laminated ring, produces flux having varying flux density (due to the gaps between the teeth on the rotor).
Airgap coils provide reduced inductance (because the coils are radially thin) that permits faster current rise times and thus, higher power at the high frequencies that are typical of flywheel devices.
Inductance is also reduced from the flux compression that occurs because the solid rotor teeth are very close to the airgap coils, and because the field circuit has relatively large air gaps.
A further advantage of the present invention is related to the smooth laminated ring that provides a site for flux diffusion that greatly reduces changing flux in the rotor and unlaminated stationary parts, thereby reducing core losses.
The armature coils are located on the surface of the smooth laminated ring so that the coils fully link the changing flux before any flux diffusion takes place.
The use of airgap armature coils enables the energy storage device to be produced in a substantially compact manner while efficiently producing high output power.
In various preferred embodiments, an annular field coil is disposed above and below the rotor (i.
e.
, two annular fields coils are used) that produce airgap flux traveling radially outward from the axis of the rotor.
In these embodiments, the solid disk design of the rotor enables the flywheel devices of the present invention to store more inertial energy than any design consisting of a similarly sized rotor utilizing a disk mounted on a shaft inserted through a hole bored into the disk, or any design using an annular rim joined to a shaft by radially oriented spokes