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Electromagnetic Flywheel

High speed flywheel with two sets of rotor coils/magnets to control and save power
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Brushless set of coils/magnets on the periphery of the flywheel produces power when recovering from flywheel (and slows flywheel down). Second brushless set(s) of rotor coils/magnets is(/are) used closer to the center of the wheel, to speed flywheel up.
Of course there is a set of brushless stators for each set of rotors. No clutch is ever used, so very little energy is lost. Heat should be used to further assist in creating work, by either a "turbo" type of steam engine (using water cooling, with excess heat creating steam being navigated back to motor) or any other means of cooling the motor while using the heat.
pashute, May 13 2008

Beacon Power Flywheels http://www.beaconpo...stems/flywheels.htm
magnetically levitated, in a vacuum [Laughs Last, May 16 2008]


       I'm sorry but I am having a hard time visualizing what you are describing. Can you give it another shot?
Ozone, May 13 2008

       Why wouldn't you just use the same coils for both adding and subtracting power ?
FlyingToaster, May 13 2008

       A flywheel is basically similar to a gyroscope device, made of material that can stand extreme tension, so that it doesnt have to be that heavy, but rather to reach extreme speeds without breaking down (without exploding to pieces). The flywheel is then used to store energy and retrieve energy, usually via a clutch device, so that once the wheel is turning very fast (the faster it goes, the more energy you have stored in it) you can retrieve the energy by using the clutch.   

       There are many toy cars with a tiny flywheel, that you run on the floor until the flywheel "gathers speed". Once up to speed you put it down, and the car continues driving with "power" that was stored in the flywheel. It goes over rug edges etc.   

       My idea is about using electromagnetic devices (coils) to store and restore power to and from the flywheel.   

       You wont use the same set of coils for getting and giving power, because close to the perimeter is the most efficient for retrieving power, and close to the middle is where you give the power over efficiently.
pashute, May 13 2008

       so.... why not use the same coils for adding and subtracting power ?
FlyingToaster, May 13 2008

       Thanks [Flying] for question. Please see former (edited) anno.
pashute, May 13 2008

       //close to the perimeter is the most efficient for retrieving power, and close to the middle is where you give the power over efficiently.//   

       Why? I can't imagine any reason why this would be the case.
MaxwellBuchanan, May 13 2008

       Flywheels have been considered for use in cars for decades. And all of them use electric motor/generators to put power into, or withdraw power from, the flywheel. Here the Idea appears to be for the flywheel to be, in essence, the motor-rotor. OK. There will still be frictional losses from the supporting bearings, unless the thing can be designed using magnetic levitation (which likely could interfere with the other fields needed to spin it up or take power from it). Good luck!
Vernon, May 13 2008

       Pashute, I disagree with:   

       /close to the perimeter is the most efficient for retrieving power, and close to the middle is where you give the power over efficiently./   

       I'm pretty sure that's flat-out wrong. Coils around the edge will be as good at applying torque to accelerate the flywheel as they are at applying torque to decelerate it again.   

       Flywheel designs exist that use magnetic bearings, passive or active, and coils to accelerate them electrically (i.e. exactly what this suggests). Baked, but definitely not widely known to exist.
david_scothern, May 13 2008

       Maybe I still don’t get it, but if I do, then you are saying that you are going to use a coil to store energy. If I’m not mistaken aren’t you describing a standard inductance coil? Good for keeping flow going for a short time but the opposite physical structure and opposite mathematical description of a capacitor is needed for storage. Unless I’m missing something here I don’t think it can work.
Ozone, May 13 2008

       No, I think the idea is for a regular flywheel which is itself a motor/dynamo.
MaxwellBuchanan, May 13 2008

       Its HB so I'm using my intuition (which obviously disagrees with many of yours). Imagine the flywheel at 50k rpm. The fastest moving coils are on the outside. (bigger distance at same time) That's where you'll get the best current, no? Close to the center you get high wheel speed for less power inserted (similar to bicycle gears), when working the other way and inserting power INTO the flywheel. So you achieve high speeds, which is what is desired.   

       [ozone] I don't get what your asking, and suppose have not got what I am saying... So here it is again: Take a (fly)wheel. put batteries and coils on the "tire" in a way that it should look like a regular electric motor (or pancake motor). Or simply put magnets on the tire. Now add a(nother) set of coils OUTSIDE the wheel. If there are inner coils, they are controlled by a computer or electronically (brushless motor). I'm using this rotor/stator pair to dampen the flywheel, by GENERATING electricity from high speed (on perpheral of wheel) of passing (electro)magnets near coils. Part 2 is the inner circle with same type of configuration. Here the stator coils are used as a motor to empower the flywheel. rotor can be perma-magnets or electro-magnets in which case they too would be controled by a computer, and have power "on board" in the flywheel.
pashute, May 13 2008

       Power is torque times angular velocity, no matter how close to or far from the hub. Power will be equal at all radii.   

       The same applies with the bicycle wheel. Changing gears varies the relative magnitudes of torque and angular velocity, however the power (from your legs) is the same, ignoring biomechanical aspects of cadence of course.   

       That said, there might be an electronic analogue to the 'cadence' point. Maybe some optimium torque and angluar velocity pairing that maximises efficiency. If so, I think it would apply for both speeding up and slowing down though.
Texticle, May 13 2008

       //Its HB so I'm using my intuition//   

       It's HB so I'm using my rudimentary grasp of physics, which says (a) the distance from the axis has no effect (speed/force tradeoff) and (b) acceleration/deceleration makes no difference (symmetry).
MaxwellBuchanan, May 13 2008

       My grandfather and some of his skunkworks cronies fooled around with this idea, or something colose to it, in the 1980s. They came up with a working prototype, but could not make it safe enough to install in a passenger vehicle without the entire assembly being too heavy to be feasible. It seems that, once they had constructed a flywheel of sufficient mass to impart a reasonable transfer cooefficient, a catstrophic rupture sent shrapnel tearing through every part, including the engine block, of what I beleive was a Plymouth Fury.
Alterother, May 15 2008

       How can two things be called the same if those two things are different ? (1=2 both are numbers)   

       You can juice the thing up while/concurrently taking juice out .
wjt, May 15 2008

       But why ? Why not utilise the energy directly (unless you wish to perform some sort of conversion) ?   

       Compressed air bearings will give extremely low friction wihout any electrical interfereence issues.   

       The main problem - if the flywheel has sufficient mass/rotation - is the gyroscopic effects when trying to manouvre the vehicle.
8th of 7, May 15 2008

       [Alterother], The correct way to use a flywheel relates to how much energy it can store. As you noted, it cannot be built to store enough to replace the ordinary gas engine and fuel tank (300-400 mile range). But it CAN store enough for accelerating the vehicle to highway speed. Note that a gas engine is typically built powerful enough to allow rapid acceleration, but when it cruises along, it actually only needs about 15-20 horespower. So, build a hybrid car that has a 20HP gas engine and a flywheel. The flywheel is gradually spun up to store energy for rapid acceleration. It gets re-spun from regenerative braking and from the unused HP available when cruising. This is perfectly practical, and actually is more practical than using batteries for equivalent energy-storage purpose(flywheels weigh less, and energy can be stored removed more efficiently, with less losses).   

       [8th of 7], the flywheel should be mounted in a car with its central axis vertical. An appropriate gimbal arrangement will allow it to stay level while the car tilts. This has actually been done that way in various experimental cars.
Vernon, May 15 2008


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