I made a post about this on EF but can also be useful here. Plus I made some proper renditions this time.
We all know that induced voltage due to some changing field is V= N dɸ/dt or rewriten to V = N A dB/dt.
So I was thinking, what if we had two coils, that experienced approximately the same dB/dt and had equal N*A. When both such coils are hooked in series, the induced emf due that field change should cancel in the total circuit. So electrically we are fine. What about mechanically.
I ran some simulations and discovered that when this two coil circuit was powered with any current the coil with the smaller area and larger turns has a dominating field strength. In other words when powered this can attract or repel a magnet for instance.
So now we combine the two, on one hand we have a setup that it's completely oblivious to changing fields, and on the other this setup can perform mechanical work.
So for instance. If the small coil has an area of 1cm² and the bigger one 4cm², then the small coil must have 4 times the amount of windings of the large coil.
small coil: 1cm² 100 turns 1A
large coil: 4cm² 25 turns 1A
It's actually not that hard to see why the small coil is dominating field wise. Field density is only turn dependent.
The tricky part is keep the flux density as uniform as possible through both coils. By using a large enough magnet for example.
Wait a second, if all we need is an uniformly changing field density through both. What would happen if these two were put in the middle of a longer coil. According to the sim the average field density through the whole setup (thus flux) is again hugely in favor of the smaller coil. If these two were set to oscillate inside a bigger coil, this bigger coil would see a constant flux change. And thus induce its own emf which results in flux. But since the two oscillating coils are oblivious to outside uniformly changing flux they won't be affected at all. Thus the primaries so to speak remain completely inductive, while "unlimited" power can be tapped from the secondary.
I have no doubt that when tweaked both coils cancel a uniformly changing field, especially if the source is another coil which they are placed at the center of. What should be tested if indeed the simulation result is correct, and that they have a non zero net average flux when powered. But this is the natural next experiment after the green coil has been tweaked properly.
Hi Broli,
Is this not along the lines of what Thane was showing with a HV coil and a LV coil in close
proximity. I think in his video, he said that he used MOT coils.
Regards, Penno
A so called HV coil or a coil with many turns should geometrically have a smaller area compared to the LV coil or a coil with not so many turns. Thane never has put any emphasis on this as far as I know.
Any known technology aside, the last setup is a relatively cheap experiment to form a conclusion about the theory.
Hi Broli,
Sorry, I should have typed, HC (high current) and HV (high voltage) coils.
I have been searching his videos to find the pertinent one.
Soon as I find it, I will post a link.
Regards, Penno
Start at this one - http://www.youtube.com/user/ThaneCHeins#p/u/22/V_UXcNMBGTA
Sure.
Tomorrow I'll try and setup a FEMM lua scripted simulation.
I don't think I need the dynamic simulation. I performed a series of static simulation in FEMM and this is what I discovered...
1) The long collector solenoid gives indeed a very ideal and uniform field. So there's an almost sure guarantee of no induced emf when the collector coil start sending its flux.
2) When both small and big area coils are energized there's a net total flux in favor of the small area coil. This net flux is approx 6-10 times smaller than the average field of the small coil if it were completely alone.
What I still haven't checked out is whether that 6-10 times ratio is dependent on which other parameters. But this is not so very important due to point 1. If the two coils can cancel each others emf completely any small net total flux caused by them can induce a voltage in the long collector coil which can be amplified to any desired level by shear oscillation frequency.
Currently the sim is using a 1:9 area and turn ratio.
Just performed experiment v0.1. Made two small coils, one has 2 times area of other but 2 times less windings. Test was done with moving magnet up and down. First each one alone in order to see voltage on scope, then hooked as shown here. EMF is canceled completely in latter case.
What I learned is that it's best to use as much windings as possible, but keeping the ratios the same of course. More windings means more precise fine tuning until you hit the exact amount of windings where both cancel. The added benefit of more windings is that you get higher voltages, since we're dealing with air coils for now that's an advantage.
Next up is experiment v0.2, bigger better faster.
While winding the different coils a new design hit me which could jack potential power generation much further up. Stay tuned. This is way too simple and is starting to scare for a potential build up of FAIL.
Edit: Attached the new design now. Same as before, V= N dɸ/dt however this time I leave it as is. Both coils have the same amount of changing flux penetrating them, and they both have the same amount of windings, hence their induced emf's cancel when hooked in series. However when energized in that configuration the smaller coil produces dominating field inside of the core which causes the green collector coil to generate current. Since our coils are oblivious to uniform flux change, which the green coil provides due to its long length, this current doesn't reduce the inductance of the coils.
Quote from: broli on January 27, 2011, 06:00:43 PM
While winding the different coils a new design hit me which could jack potential power generation much further up. Stay tuned. This is way too simple and is starting to scare for a potential build up of FAIL.
Edit: Attached the new design now. Same as before, V= N dɸ/dt however this time I leave it as is. Both coils have the same amount of changing flux penetrating them, and they both have the same amount of windings, hence their induced emf's cancel when hooked in series. However when energized in that configuration the smaller coil produces dominating field inside of the core which causes the green collector coil to generate current. Since our coils are oblivious to uniform flux change, which the green coil provides due to its long length, this current doesn't reduce the inductance of the coils.
What if you had multiple blue coils evenly spaced along the green coil so as to not interfere with each other but are in series or even parallel?
Quote from: jbignes5 on January 27, 2011, 11:16:31 PM
What if you had multiple blue coils evenly spaced along the green coil so as to not interfere with each other but are in series or even parallel?
That should increase output. But remember since this is using a core the output is limited to the saturation point of the core. What I also haven't mentioned so far is that this also works on a closed loop core like a toroid or some other type, in fact more flux is trapped that way.
Attached you see such toroid simulation. However this time the smaller coil is no longer dominating, it's the larger coil that is. Smaller coil has north pointing right, for large it's pointing left. Again collector coil should be wound uniformly around toroid.
EDIT: Just redid sim in FEMM and attached result. FEMM is showing that again the smaller coil is dominating opposed to vizimag's result.
EDIT2: I'm going to stay clear from close looped cores for now, the results are very mixed between FEMM and vizimag for the same setups, unlike the long solenoid setups.
Just finished doing a first experiment using the above design. I used a long stainless steel rod which is from an old printer, so it's properties as a core aren't the best but it should be enough to prove the point.
The long solenoid has probably 200+ turns and this is what gets energized. I included two scope shots, one when only one coil is connected and then one when both are in series. Both coils have 20 turns. As you see the voltage drops to zero in series.
Further, I used simple cell phone adapter as AC source, removed the rectifying bridge and filtering cap to get a 50Hz signal.
One scope shot might seem strange. That's because when I dumped the pictures to my usb stick on the scope the data came through but not the wave. So I just took a real picture and pasted it on it to give you an idea of how it looks.
For now the reverse, energizing the two coils in series, gives only a sine wave of 20mV amplitude in the long solenoid. This low number is to be expected and can be increased with a proper and bigger core, more windings and higher frequencies.
Wow, not much involvement is there.
Can someone with a large toroid core from a joule thief experiment or so perform this experiment and report the results? The coils can be driven with any kind of wave form.
Hi Broli,
http://www.youtube.com/user/ThaneCHeins#p/u/3/Ps5BqEiFK74
This was the video I was searching for.
Here you can clearly see four cores from MOTs.
The two HC coils closest to magnets then the two HV coils behind them.
Regards, Penno
@broli,
did you get a chance to watch that video ?
Penno
Quote from: broli on January 25, 2011, 02:36:50 PM
Wait a second, if all we need is an uniformly changing field density through both. What would happen if these two were put in the middle of a longer coil. According to the sim the average field density through the whole setup (thus flux) is again hugely in favor of the smaller coil. If these two were set to oscillate inside a bigger coil, this bigger coil would see a constant flux change. And thus induce its own emf which results in flux. But since the two oscillating coils are oblivious to outside uniformly changing flux they won't be affected at all. Thus the primaries so to speak remain completely inductive, while "unlimited" power can be tapped from the secondary.
I have no doubt that when tweaked both coils cancel a uniformly changing field, especially if the source is another coil which they are placed at the center of. What should be tested if indeed the simulation result is correct, and that they have a non zero net average flux when powered. But this is the natural next experiment after the green coil has been tweaked properly.
Hi Broli,
I like this idea and think I understand why the two primary coils cancel out induced bemf from the secondary. So I am willing to give it a try and will try to reproduce the effect by using your setup with the core rod (green secondary coil with two blue primary coils), should be easy to replicate.
What I am not so clear about is, your statement that Thus the primaries so to speak remain completely inductive, while "unlimited" power can be tapped from the secondary. As for my understanding the two primary coils would induce some amount of flux into the core which will induce some energy into the secondary coil. Depending on the geometry of the primary coils more or less flux can be induced but at least as much as one of the primary coils is able to. Wouldn't be the input power be always greater than the ouput power? Or do you mean by "Unlimited" power, that the secondary circuit could produce more power than what is induced by the primaries due to the bemf-independence of the primaries? I feel that I am not getting this right, but would you be so kind to explain that part a little bit further?
Best wishes,
Magnetizer
In a regular transformer the secondary drops the inductive impedance of the primary, in essence making it less inductive which causes a current rise. The concept of this was that there's no flux coupling, so the secondary would produce power while the primary gets to keep its inductiveness.