i have looked in to this before ( not too deep) but enough to say that the coils he is using are wound in a particular order if some one had time to look it up and post it here.
i know this as there was some videos posted somewhere where he described this.
the coils from what i understand are wound from one end to the other then jump back and start winding again. this will be the best way to get the most out of the coil in this system. and everything is precisely wound as wire placement must make a huge deference... just my 2 cents...
~Russ
Interesting. Thanks for the tip Russ.
It would seem to me with an air core, this winding pattern would be relatively easy to do--use a bobbin with slits cut on each end, make a complete wind starting from the left slit, then exit the slit on the right, wrap through the bobbin air center, enter again on left and repeat. Can't be any more difficult than winding toroids. I'm not certain how this winding pattern would be beneficial, but given it's ease, it is worth a try. I'll see if can put together an air core winding like this, this weekend and a simple rotor with only two magnets. Shouldn't be too difficult to experiment with gating/timing to see if I can charge and dump caps without noticeable back EMF on the rotor. What I'm not sure of is do I select capacitors of such value they completely charge in a single pass or would I want to select large capacitors and have multiple passes charge them--step charging? I can't imagine I would get enough of an impulse from a single peak to do much of anything, but maybe I can. Doug mentions something about "coil shorting" which I really don't understand at the moment. Regardless, it would seem the rotor RPM, coil and capacitor all must be in some ballpark area in order to get the electronics to be of much help. I'll give it a shot and see what it does--the clock is ticking...
Another thought that just occurred to me... If the voltage generated by the coil (consider number of turns, RPM and magnet size/placement) is just slightly higher than typical diode biasing (0.7V or 1.4V for a bridge), I could directly rectify and store to the cap without any gating since the diodes would only grab the peak voltage anyway, albeit the capacitor wouldn't charge to very high voltage, but it would charge only on the peak, without any additional gating circuitry. I'll have to think about the practicality of this some more, since I'm interested in the effect yes, but I really want something to charge common 12V batteries that can then run bigger applications. Then again, the individual coils wouldn't be coupled, so with multiple coils all charging in independently (in parallel), I could just dump them all together in series--charge individually, dump together. This may well work and use very few electronic components.
This may or may not be the video you were thinking of Russ:
https://www.youtube.com/watch?v=Q1SNYAoEak0