1. A wire-wound rotor for use in a flywheel rated for an operational speed range, the rotor comprising:
a flywheel core with a winding surface; and
a mass of wire wound onto a flywheel core, the wire preloaded such that all layers of wire exert a net radial force that is compressive throughout the operational speed range of the flywheel.
2. The wire-wound rotor of claim 1 wherein the wire is wire-drawn steel.
3. The wire-wound rotor of claim 2 wherein the steel wire has a tensile strength and a yield strength of at least 250,000 psi.
4. The wire-wound rotor of claim 2 wherein the steel wire has a tensile strength and a yield strength of at least 300,000 psi.
5. The wire-wound rotor of claim 2 wherein the steel wire has a tensile strength and a yield strength of at least 400,000 psi.
6. The wire-wound rotor of claim 2 wherein the steel wire has a carbon concentration of between 0.50% and 0.99%.
7. The wire-wound rotor of claim 2 wherein at least one property of the steel wire changes as a function of radial position within the wire mass.
8. The wire-wound rotor of claim 7 wherein a diameter of the steel wire changes as a function of radial position within the wire mass.
9. The wire-wound rotor of claim 7 wherein the steel wire in an inner layer of the wire mass has a lower fatigue strength than the steel wire in an outer layer of the wire mass.
10. The wire-wound rotor of claim 2 wherein successive layers of steel wire are wound to cross each other.
11. The wire-wound rotor of claim 2 wherein successive layers of steel wire are wound along a same direction.
12. The wire-wound rotor of claim 2 wherein the wire mass comprises at least two separate segments of steel wire located at different radial positions.
13. The wire-wound rotor of claim 2 wherein the wire mass comprises at least two separate segments of steel wire located at different axial positions.
14. The wire-wound rotor of claim 2 further comprising a matrix material used to fix the steel wire within the wire mass.
15. The wire-wound rotor of claim 14 wherein the matrix material is an epoxy resin.
16. The wire-wound rotor of claim 14 wherein the matrix material is a vinyl ester resin.
17. The wire-wound rotor of claim 2 wherein the outermost layer of steel wire is mechanically constrained within the wire mass.
18. The wire-wound rotor of claim 2 wherein the steel wire is rectangular steel wire.
19. The wire-wound rotor of claim 1 wherein the wire is preloaded such that all layers of wire experience tension hoop stress at 0 rpm.
20. The wire-wound rotor of claim 1 wherein the wire is preloaded such that some layers of wire experience compressive hoop stress at 0 rpm.
21. The wire-wound rotor of claim 1 wherein the wire is preloaded such that the preload increases monotonically as a function of radial position within the wire mass.
22. The wire-wound rotor of claim 1 wherein the preload is established by winding the wire onto the flywheel core under a winding tension.
23. The wire-wound rotor of claim 22 wherein the winding tension is constant for substantially all wire in the wire mass.
24. The wire-wound rotor of claim 22 wherein the winding tension varies as a function of radial position within the wire mass.
25. The wire-wound rotor of claim 22 wherein the winding tension increases monotonically as a function of radial position within the wire mass.
26. The wire-wound rotor of claim 1 wherein the operational speed range includes a tip speed for the wire mass of 200 ms.
27. The wire-wound rotor of claim 1 wherein the operational speed range includes a tip speed for the wire mass of in a range of 75 ms to 500 ms.
28. The wire-wound rotor of claim 1 wherein an inner diameter of the wire mass is less than 85% of an outer diameter of the wire mass.
29. The wire-wound rotor of claim 28 wherein an inner diameter of the wire mass is in a range of 20-75% of an outer diameter of the wire mass.
30. The wire-wound rotor of claim 1 wherein an inner diameter of the wire mass is in a range of 75-95% of an outer diameter of the wire mass.
31. The wire-wound rotor of claim 1 wherein an outer diameter of the wire mass is at least 1.5 times the height of the wire mass.
32. The wire-wound rotor of claim 1 wherein a height of the wire mass is at least 1.5 times an outer diameter of the wire mass.
33. The wire-wound rotor of claim 1 wherein the wire mass accounts for at least 50% of a total mass of the rotor.
34. The wire-wound rotor of claim 1 wherein the flywheel core is solid metal occupying all of the space between a shaft and the winding surface.
35. The wire-wound rotor of claim 1 wherein the flywheel core comprises a hub and an annular drum, the hub extending from a shaft to an inner surface of the drum, the hub occupying less than all of the space between the shaft and the inner surface of the drum, the outer surface of the drum being the winding surface.
36. The wire-wound rotor of claim 1 wherein the flywheel core comprises wound wire bound with a matrix material.
37. The wire-wound rotor of claim 1 wherein the flywheel core comprises axial support structures that extend radially beyond the winding surface.
38. The wire-wound rotor of claim 1 wherein the flywheel core comprises:
a cylindrical drum having an outer surface that serves as the winding surface; and
at least two end plates affixed to the cylindrical drum, to form a channel with the winding surface, the wire mass occupying the channel.
39. A flywheel assembly comprising:
a shaft;
a flywheel rotor fixed to the shaft, the flywheel rotor comprising:
a flywheel core with a winding surface, and
a mass of wire wound onto the flywheel core; and
a motor having a motor rotor and a motor stator, the motor rotor fixed to the shaft and using electrically non-conductive permanent magnets.
40. The flywheel assembly of claim 39 further comprising:
a vacuum vessel, wherein the shaft, flywheel rotor and motor rotor are located inside the vacuum vessel and rotate in a vacuum.
41. The flywheel assembly of claim 39 wherein the permanent magnets comprise ceramic ferrite magnets.
42. The flywheel assembly of claim 41 wherein the permanent magnets comprise barium iron oxide (BaFe2O3) magnets.
43. The flywheel assembly of claim 41 wherein the permanent magnets comprise strontium iron oxide (SrFe2O3) magnets.
44. The flywheel assembly of claim 39 wherein the permanent magnets have a resistivity of at least 1E6 ohm cm.
45. The flywheel assembly of claim 39 wherein the motor is a radial gap motor.
46. The flywheel assembly of claim 45 wherein the motor rotor is radially located inside of the motor stator and faces outward, the motor stator facing inward.
47. The flywheel assembly of claim 45 wherein the motor rotor is radially located outside of the motor stator and faces inward, the motor stator facing outward.
48. The flywheel assembly of claim 39 wherein the motor is an axial gap motor.
49. The flywheel assembly of claim 48 wherein the motor rotor includes a disk located between two motor stator disks.
50. The flywheel assembly of claim 48 wherein the motor stator includes a disk located between two motor rotor disks.
51. The flywheel assembly of claim 39 wherein the motor rotor further comprises a non-conductive sleeve to mechanically support the permanent magnets.
52. The flywheel assembly of claim 39 further comprising:
a head cover and a housing, which together form a vacuum vessel, wherein the shaft, flywheel rotor and motor rotor are located inside the vacuum vessel and rotate in a vacuum, the head cover located mostly above grade and the housing located mostly below grade, the flywheel rotor located mostly within the housing.
53. The flywheel assembly of claim 52 further comprising:
an upper bearing, a thrust bearing, and a lifting magnet, all of which and the motor stator are mechanically fixed to the head cover.
54. A frequency regulation system comprising:
a flywheel energy storage system connected to a utility electricity grid, the flywheel energy storage system comprising at least one flywheel assembly, the flywheel assembly comprising:
a flywheel rotor comprising a flywheel core with a winding surface, and a mass of wire wound onto the flywheel core; and
a motor having a motor rotor and a motor stator, the motor rotor using electrically non-conductive permanent magnets, the motor rotor and flywheel rotor mechanically fixed to rotate together; and
a controller that transfers energy between the flywheel energy storage system and the utility electricity grid based on mismatches between electricity generation on the grid and electricity load on the grid.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A non-transitory computer readable medium containing instructions for a computer and a mobile device having a Global Positioning System (GPS) receiver, a processor, and a memory device, wherein the computer and mobile device are selectively linked together and the instructions cause:
the processor to save user specific data to the memory device;
the processor to save GPS data generated by the GPS receiver to the memory device in response to a command from a polling system coupled to the mobile device;
the mobile device to transfer the saved GPS data from the memory device to a reporting system coupled to the computer; and
the computer to process the saved GPS data into a user report.
2. A non-transitory computer readable medium according to claim 1, further comprising polling the GPS receiver for GPS data by at least one of a selectable time increment and real-time data streaming.
3. A non-transitory computer readable medium according to claim 1, wherein transferring the saved user specific and GPS data to the computer comprises transmitting the data wirelessly.
4. A non-transitory computer readable medium according to claim 1, further comprising presenting a user interface on a display of the mobile device.
5. A non-transitory computer readable medium according to claim 4, wherein the user interface comprises:
a data entry field corresponding to the user specific data;
a data entry field corresponding to a type of GPS data to be saved; and
a command button adapted to signal the polling system when to begin and end saving GPS data.
6. A non-transitory computer readable medium according to claim 1, wherein the memory device comprises a removable computer readable medium.
7. A non-transitory computer readable medium according to claim 1, further comprising managing the saved user specific and GPS data for multiple users and mobile devices.
8. A non-transitory computer readable medium according to claim 1, wherein the user report comprises at least one of a completed tax form, an expense report, and a mileage tracking log.
9. A computer-implemented system for managing data received from a Global Positioning System (GPS) enabled mobile device having a GPS receiver, a processor, and a memory device, comprising:
a polling system linked to the GPS enabled mobile device and configured to:
save user specific data to the memory device; and
selectively cause the processor to save GPS data received by the GPS receiver to the memory device; and
a reporting system selectively linked to the memory device and configured to:
receive the saved user specific and GPS data from the memory device; and
process the user specific and GPS data into a report.
10. A computer-implemented system according to claim 9, wherein the polling system is embedded with the GPS enabled mobile device.
11. A computer-implemented system according to claim 9, wherein the polling system is further configured to set a time increment between a set of data points for the saved GPS data.
12. A computer-implemented system according to claim 9, further comprising a user interface presented on a display of the GPS enabled mobile device.
13. A computer-implemented system according to claim 9, wherein the user interface comprises:
a data entry field corresponding to the user specific data;
a data entry field corresponding to a type of GPS data to be saved; and
a command button adapted to signal the polling system when to begin and end saving GPS data.
14. A non-transitory computer readable medium according to claim 9, wherein the reporting system is configured to receive the saved user specific and GPS data from the GPS enabled mobile device wirelessly.
15. A computer-implemented system according to claim 9, wherein the reporting system comprises a database configured to be coupled to a computer system and adapted to manage GPS data for multiple GPS enabled mobile devices.
16. A computer-implemented system according to claim 9, wherein the user report comprises at least one of a completed tax form, an expense report, and a mileage tracking log.
17. A computer-implemented method for collecting and reporting travel information collected by a Global Positioning System (GPS) enabled mobile device having a GPS receiver, a processor, and a memory device, comprising:
coupling a polling system to the GPS enabled mobile device;
communicating a first signal generated by a polling system to the processor, wherein the first signal causes the processor to start saving UPS data received by the receiver to the memory device;
communicating a second signal generated by the polling system to the processor, wherein the second signal causes the processor to stop saving GPS data;
transferring the saved GPS data to a reporting system coupled to a computer system; and
processing the saved GPS data into a report based upon the collected GPS data and a predetermined set of criteria.
18. A method according to claim 17, further comprising presenting a user interface coupled to the polling system and adapted to:
save a set of user specific data to the memory device;
receive instructions relating to a type of GPS data to be saved to the memory device;
initiate the generation of the first and second signal; and
initiate the transfer of the stored GPS data to the reporting system.
19. A method according to claim 17, wherein transferring the saved GPS data to the reporting system comprises transmitting the set of user specific data and GPS data wirelessly.
20. A method according to claim 17, further comprising providing the report as at least one of a completed tax form, an expense report, and a mileage tracking log.