Uninterruptible power supply using a high speed cylinder flywheel
US6825588B2 · kind B2 · utility
Inventors
Key dates
| Filing date | Dec 20, 2002 |
| Grant date | Nov 30, 2004 |
| Priority date | — |
| Expiry date | Dec 23, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E60/16
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A flywheel uninterruptible power supply includes a solid steel cylindrical flywheel levitated for rotation about a vertical axis at tip speeds greater than 250 m/s on magnetic bearings in a low pressure housing. The cylindrical flywheel has a length L and a diameter D, wherein L/D≧1.0. A motor/generator attached to said flywheel accelerates the flywheel and maintains it at operating speed for storage of energy; and decelerates the flywheel for retrieval of the stored energy. The flywheel inertia section operates with a maximum stress of greater than 60% and less than 80% of the material yield stress when spinning at fully charged operating speed. The flywheel is constructed from steel with an ultimate strength greater 150 ksi and a toughness greater than 100 ksi (in)^1/2. The flywheel is a solid steel cylinder that is hardened to centerline structure throughout the axial thickness of the large diameter portion that is greater than 40% martensite. The flywheel is a solid steel cylinder that, in normal, fully charged operation, spins at a speed that would cause a fracture failure no sooner than one hundred thousand cycles between the fully charged normal operating speed and te…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.