 |
|||
|
Power and Motion |
Comparison of RPM's Flywheel Battery with Others
Our flywheel battery is far different from any others, mainly due to its nearly zero storage (idling) losses, zero maintenance, and unlimited service life. It was created to meet a vast need for practical environmentally-responsive power storage. Rotational dynamics, magnetic fields and forces, power electronics, advanced materials processing, and system integration, with pioneering architecture in building-integral power systems, are a few of its important elements.
We looked far beyond existing markets, applications, products, and competitors. Our work, to meet goals we set forth, was a challenge well met by the RPM (Regenerative Power & Motion) startup team, and their unique interdisciplinary capabilities.
We were able to achieve important competitive advantages over other flywheel batteries, which don't meet the needs of our intended market. We achieved our goal by focusing our efforts on stationary, on-site UPS (Uninterruptible Power Supply) with practically no losses.
Our development and marketing strategy: To provide a complete utility power backup UPS, for an existing market we can grow; plus UPS having ultra-efficient long-term power storage, for new building-integral solar and wind power systems -- an emerging market with vast global potential. Both markets will be served by similar RPM flywheel battery technology.
Accordingly, we are developing advanced proprietary technology for clean, convenient, cost-competitive, dependable, safe, environmentally responsive, on-site electric power conversion and storage.
We will develop a small 3-kwh system first, at minimal risk, for existing and fast growing intranet and internet server and router UPS requirements. Then we will develop a larger 50-kwh system.
Parallel connection of 2 or more systems will accommodate a variety of power storage needs with one model, and dramatically increase UPS reliability.
Our systems' life-cycle cost will be lower than lead-acid batteries, fuel-burning engines and generators, and other flywheel batteries. Performance, safety, and practicality will be far superior. Environmental benefits will be profound.
Urgently needed and fast growing application: Uninterruptible on-site power, as more reliable UPS systems that provide crucial power during utility line outages, for intranet and internet servers and routers. Ultimate applications: UPS with on-site solar and wind power generation systems.
Other flywheel batteries supply power for only seconds or minutes, and
self-discharge in hours. Their motor/generator's ball bearing and magnetically
cycled iron core losses are partly 
responsible.
Ours can supply power for days, and can store it without substantial self-discharge
for years; due in part to our patented m/g's lack of hysteresis and eddy
losses, and to its contactless bearings. Mechanical backup bearings are
engaged only during non-operating modes like transit and storage, before
power-up and after power-down.
Others have mechanical bearings in motor/generators that are continuously engaged (i.e, always running) and get extremely hot -- and fail due to heat and wearout.
Ours have proprietary integral contactless magnetic bearings, motor/generator rotor, and flywheel. They incur practically zero idling losses (only from infinitesimal eddy currents and hysteresis, due mainly to practical production tolerances) - and can run essentially forever.
Others use conventional mechanical bearings for transit and magnetic
bearing backup (or may have mechanical bearings that are always engaged).
Their lubrication problems, at high rpm in a vacuum, will also cause early
failures (from wear, pitting, and heat, caused partly by their conventional
ball or roller bearing sliding retainer cages).
Ours (at right) have rolling contact backup bearings (with no sliding retainer cages). These bearings are not engaged while our flywheel battery is in service. They are far less dependent on lubricants. We expect their normal service life will be indefinitely long, comparable to other RPM flywheel battery subsystems, which run continuously while our flywheel battery is in use. Besides the normally short duty for these mechanical bearings, rotor weight is substantially and continuously supported by permanent magnets in the axial magnetic bearing.
Others use elaborate rotor coupling devices, to accommodate a motor/generator with ball bearings, and a flywheel supported by magnetic bearings. Their conventional iron-core m/g has high hysteresis and eddy losses. Their m/g ball bearings, running continuously at high speed in vacuum, will indeed be short lived, running very hot while dissipating high idling power. Their general-use magnetic bearings have high hysteresis and eddy losses, causing a total idling loss of 2-kw for some, and further shortening self-discharge to typically minutes.
Our
total and integrated design approach, with coreless, ultra-efficient m/g
having practically zero idling losses; integral with magnetic bearings
specifically designed for vertical-axis rotors, that are inherently
stable radially, and self-adjust long-term axial rotor position for zero
electromagnet power; have no friction or hot spots, and dissipate practically
no idling power at normal running speeds.
We even use gravity and rotor gyro dynamics to advantage: At any global location, excepting the earth's poles, a precession torque tending to tilt the rotor's axis, is caused by the earth's rotation of 1-revolution per day. By magnetically hanging the rotor from a high location relative to its center of gravity, this tilt is limited to a degree or so by inherent gravity and gyro stabilization.
Others enclose flywheels in heavy and costly enclosures, intended to contain a possible explosion. Our electronics starts a power-down, if our flywheel vibrates excessively. And our flywheel is normally installed in an underground site that can safely absorb a maximum energy, rapid discharge flywheel explosion.
With
a focus on realistic applications, we have developed a minimum cost, maximum
performance, dependable, zero maintenance, power storage system. We envision
it enhancing exciting solar power construction projects like the Natatorium,
for the 1996 Olympics in Atlanta. Photo at left shows it under construction.
It's a link
to more projects like it.
RPM's startup team appreciates your interest in our venture. Our work covers 2 decades of evolving engineering analysis, design, breadboarding, prototyping, and test. We love this work and the great friends who help and encourage us.
Explore our other pages: HOME (for an overview), TUTORIAL (a good place to look for a review of basic flywheel physics and different implementations), our Business Plan Abstract (to see what we've achieved and our future plans), and our RESOURCES.
You may also like to see how we might play an awesome role, to enable practical, low cost, convenient, wide scale use of safe high-performance Electric Vehicles with no range limitations.
If you have questions, comments, or suggestions, email me: fradella@earthlink.net
Links to flywheel batteries,
solar and wind power, dual-mode EVs, and a plan to achieve them
Urban EV with Onboard Batteries,
Charger, PV, Regenerative Motor, Pedals
