Muller Dynamo

[k4zep]

Ben,   Very nice work.   
I like the idea of "The driver is JUST a hall effect"
Very simple and easy pulse motor. 
Now you can focus on the generator part.
I am doing similar experiments. 

Bill

Thanks Bill,

Didn't feel so great today so rested a lot and tied up loose ends.  Glued in magnets, balanced wheel, turned down top collar of bearing
to keep it clear of rotor, attached small switching power supply from China, tested.  Arrrrrggggg.  Power supply has a static drain of around 11 ma, which is almost the same as the rotor draws!  but nice to have a small power supply on rotor mount.  Rotor turns about 1225 @ 8VDC,  1700+@ 12VDC and 2200+@ 15VDC.  All current drains about 15-20 ma.  As RPM goes up, current drain goes down.  So if I feel good tomorrow, will build adjustable mount for two coil forms sitting on top of rotor,  wind "special" coils, and start adjusting/tuning/playing around with the hard stuff.  Not in a race here, just slow plodding along as/when I feel up to it.....

Respectfully
Ben K4ZEP

[Rawbush]

Thought you guys might find this interesting.
There is a plastics shop in the Denver area called "Plasticare"
Their web site is: http://www.plasticareinc.com/

They laser cut three 7" diameter by 1/2" thick rotors complete with all the necessary holes for only $45 for all three.

They did a very nice job but I might have to work on the hub a little to get it perfectly square with my shaft.
Still a work in process. I think I am going to increase my shaft size from 1/4" to 3/8" and use stainless steel instead of plain steel.

That is all for now.

}:>

I use to buy fiberglass products from them ( Heath still work there?) I live in Loveland now and there is a plastic store in Ft collins that does the same stuff. May have to try to hook up some time, I get down to Denver about once a month or so.

[penno64]

@bolt,

How I wish you are right.

Can you please point out, in the first video of Romero's dynamo (the 12:19 one),
where the capacitor that converts vars to useable power is ?

http://www.youtube.com/overunitydotcom#p/u/19/8KVU3ZM14rw

Regards, Penno

[synchro1]

Lasersaber has confirmed my test results. He demonstrates dramaticly how magnets increase output in his latest video: 　

http://www.youtube.com/user/lasersaber#p/u/0/CVT5ZleK5rY

[Jdo300]

Hello Everyone,

I have been quietly watching the progression of this thread for several days now, and though I have been working mostly in the background to understand the basics of this stuff, I thought I would finally chime in and contribute something.

I think that you all should really pay more attention to the posts made by Bolt. He is very much a senior member on this forum and has contributed many, many insightful ideas that should not be overlooked. In particular, the post he made here was particularly instructive to my understanding:

http://www.overunity.com/index.php?topic=3842.msg290450#msg290450

The above post is simply a reiteration of what Bolt has been trying to speak to everyone since the beginning of this thread, and it took me a couple of read-throughs to really understand the essence of what he was trying to explain. But to help me really intuitively understand what was happening, I took some time and drew up a few quick simulations in the Java circuit simulator to observe the effects of tuning to series resonance on a simple 1 to 1 transformer. Recall that the primary "effect" of the coil acceleration is due to the 90-degree phase shift of voltage to current in the generator coils.

The first attached picture at the bottom of this post is a screenshot of the circuit that I ultimately ended up with.

As I continued to play with the idea, my thought was to model the circuit using the real inductance values of the pulse motor I have (which are 1.1 mH and 0.5 Ohms). So, I modeled the transformer as a 1:1 winding ratio with a inductive coupling coefficient of 0.3 (so basically the coils were loosely coupled magnetically). This was meant to simulate the magnets moving past the coil and electrically, the behavior is close enough to simulate with reasonable accuracy.

The 400 Hz input frequency was arrived at by calculating the speed of the motor to be 6000 RPMs. At this speed, the tuning capacitances would be low enough to realistically deal with. After setting these values, I calculated the necessary capacitance to put the generator coil into resonance (which was 143.9 uF). I also added the same value to the input side in a parallel resonance circuit to reduce the input power requirements as well (not required since the input represents a magnet rather than transformer).

The two 100uF capacitors may not necessarily need to be there but I found that the output current and voltage waveforms on the coil looked cleaner with them present. My assumption for the time being is that it somewhat decouples the output circuit from the resonant tank circuit of the coil. As for the DC Bridge rectifier portion of the circuit, I just arbitrarily choose a value for the DC smoothing cap and load resistor.

What I found was that when the output coil was properly tuned to resonance, the current waveform coming out of the coil did lag the voltage waveform by 90 degrees. But when the circuit got detuned, the voltage and current waveforms would be aligned with eachother. Factors that initially affected this were the resistance of the coil (represented by the 500mOhm resistance), and the load resistance on the bridge rectifier.

After playing with the model more, I finally found that the load resistance did not change the phasing of the coil as long as the 100uF caps were in place, Without them the waveform became heavily distorted which made it hard to make an accurate phase measurement.

However, the most wild thing about this particular circuit was the input and output values that were observed. I set the load resistance to 20Ohms with the input voltage being 300V (assumed to be the open-circuit output voltage of my pulse motor's coils at 6000 RPMs). With these settings, the input power was only about 20-30W peak while the output power across the 20 Ohm load was close to 1.7 kW. Of course, I was quite skeptical of these results and attempted to reproduce the schematic in Multisim to confirm the results that I was seeing. I took a screenshot of the setup (Attached below).

Using realistic circuit models for the bridge rectifier, I found that the output power was far lower than what the Java simulater predicted, however, I was very pleased to find that the phase behavior of the coil with and without resonance, and with light and heavy loads agreed 100% with the results I obtained in the Java simulator.

So now armed with these confirmations, the question to ask is why the coils would cause the generator to accelerate under load rather than decelerate. The simple answer is because the delay in current production also causes a delay in the magnetic field production. Since under normal circumstances, the induced voltage and current are in phase with eachother, the magnet experiences drag as soon as its movement induced an EMF in the coil. However in the resonant state, the magnetic field would be delayed by up to 90 degrees from the initial EMF.

For most coil geometries (particularly, a simple solenoid coil), the induced voltage positive and negative peaks occur when the magnet’s center is directly over the edge of the coil. This means that in the resonant state, the current would not even begin to rise until the magnet is almost under the coil or at top dead center (TDC). At this point, that means that any repulsion force generated by the coil would either have a reduced effect on the magnet or actually accelerate the magnet out from under the coil if the delay was far enough. This explains why high impedance coils naturally posses this quality â€" simply because the impedance of the coil added a sufficient delay to the generation of the magnetic field so as to give the moving magnet enough time to move under and away from the coil before experiencing significant drag.

- Jason O

EDIT: Also, forgot to mention this but for those who would like to get up to speed on the basics of AC rective power and VARS, check out this video here. The author does a pretty good job of explaining things and has a bunch of other nice videos on his YouTube channel explaining other topics with AC power:

http://www.youtube.com/watch?v=g0S-XV-BiUA&feature=related