Electromechanical flywheel device
An electromechanical flywheel machine includes a flywheel mass and a motor-generator having a rotor rotatable about a stationary inner stator having stator windings.
1. An electromechanical flywheel method comprising the steps of:
placing a rotatable group within an upstanding vacuum vessel, the rotatable group including an elongated cylindrical flywheel mass encircling and attached to a cylindrically arranged homopolar motor-generator rotor;
attaching a multi-ring homopolar motor-generator stator and an upper electromagnetic bearing stator to a post extending downward from a vacuum vessel top;
in a cylindrical rotor wall, placing radial pluralities and axial pluralities of laminated magnetic path assemblies arranged as a lattice, each laminated magnetic path assembly for completing a staggered magnetic path between adjacent stator rings;
inserting the motor-generator and bearing stators in an open upper end of the rotatable group;
in a non-levitating flywheel operating mode, supporting the rotatable group with a support pin centrally affixed to a conical hub that coaxially joins a lower end of the cylindrical rotor;
in a first levitating flywheel operating mode, levitating the rotatable group with bearings including a lower electromagnetic bearing having a lower electromagnetic bearing rotor fixed to the support pin; and,
in a second levitating flywheel operating mode, centering the rotatable group with an upper electromagnetic bearing including the upper electromagnetic bearing stator.
2. The electromechanical flywheel method of claim 1 further comprising the step of:
assisting the levitating flywheel operation via opposed permanent magnets including a first permanent magnet fixed to the support pin and a second permanent magnet beside the lower electromagnetic bearing.
3. The electromechanical flywheel method of claim 1 further comprising the step of:
providing field windings encircling a motor-generator rotor rotation axis, the field windings between adjacent stator rings; and,
wherein the rings have peripheral slots, the slots of adjacent stator rings aligned to receive plural armature windings with end turns above and below the motor-generator stator.
4. The electromechanical flywheel method of claim 1 further comprising the step of:
interposing heat pipes in multiple stator ring slots for conducting heat away from armature windings and the motor-generator stator.
5. The electromechanical flywheel method of claim 1 further comprising the step of:
wherein the post has a central void; and,
receiving in the void a circulating liquid coolant for cooling armature windings and the motor-generator stator.
6. The electromechanical flywheel method of claim 1 further comprising the step of:
placing a first vacuum drag pump between an annular end of the flywheel mass and a periphery of a stationary group top assembly.
7. The electromechanical flywheel of claim 1 further comprising the step of:
cooling armature windings and the motor-generator stator via discharge of a liquid coolant from an open end of a stand-pipe centrally located in the post.