Muller Dynamo

[e2matrix]

Hi, someone mentioned rotor height adjustment earlier, heres what i did.
http://img860.imageshack.us/img860/9404/rrotorheightadj01.jpg
http://img829.imageshack.us/img829/8135/rassembled02.jpg
http://img848.imageshack.us/img848/6374/rassembled01.jpg
A s/steel bolt with the top machined to move the rotor shaft up and down.

Awesome work you guys, some amazing constructing/testing your doing

Hi electr0n,  welcome to OU.  Very nice build there.  May I ask what diameter are your plastic bolts and where you might get those?  I've considered plastic bolts or the other option is to have larger top and bottom plates so the steel bolts can be further out but that might lead to flexing without also increasing the thickness of them. 

[electr0n]

@chrisC & maw2432, the bearing size is OD 18.92, ID 6.77 and height 5.86mm. They were raided from a stepper motor which i thought looked similar to romeroUK`s, a standard sealed bearing.
Im not an engineer... and have trouble sawing wood straight, so i wont comment on the best solution for bearings.
@K4zep The last lot of photos you posted with your workshop & replication, inspire alot of people, including me.
@toranarod nice job

Jim

[i_ron]

I've still got about 10 more pages to read before I'm caught up again but there's something nagging me that I haven't seen discussed here yet. Did anyone notice that the Gen II version of the Muller motor alternates rotor magnet polarity? I've got a feeling that by doing this there will be a speed or frequency at which the generator coils become self resonant, ESPECIALLY if they are bifilar wound. Should that occur, power outputs should fly off the map! 

Just an observation.

Z

zero,

the all one polarity magnets in R's machine are necessary because  alternating polarity would require an H bridge to switch the two power coils.

also the polarity of the helper magnets would only be correct 50% of the time, so scratch that one...

Ron

[electr0n]

@e2matrix, Thanks:), the threaded rod, bolts and washers wore bought from
http://www.hiq.co.nz/datapagesplastic/web10p-screws-nuts.pdf
threaded rod M12 X 1M 08-PNS12-100 (12mm)
nylon nuts M12 09-PNN12C.
Jim

[e2matrix]

Yes in a single coil pair (consisting of one coil at the top and one coil at the bottom) the two coils are in series (the induced voltages add) and there is no or negligible phase difference between such two coils so that they can be connected in series without any phase loss. 
BUT there are 7 coil pairs (i.e. 14 generator coils) and they 'see' the approaching and leaving rotor magnets at different times: this is what makes the individual output voltage of any randomly chosen coil pair differ in phase with respect to any other coil pair.
You can see how the coils and the magnets are positioned in a given moment with respect to each other either in Page 9 or in Page 17 of the PDF file Stefan collected from members contributions:
http://www.overunity.com/index.php?action=downloads;sa=downfile&id=471

So there is the need for using individual diode bridges for any one coil pair as Romero had and join the DC outputs of the diode bridges into a common positive and common negative point to charge a common puffer capacitor.

To reduce power loss due to the bridges, perhaps the output voltage levels induced could be increased so that the relative loss gets less or find diodes with smaller forward voltage losses like power Germanium types from the past (Schottky types were found bad performers! as Romero noticed) and ultimately MOSFETs as syncronous rectifiers could be used. HOWEVER, working on all such fine details to improve the setup should come AFTER a succesfull replication, this is what I think.

Gyula

OH NO - regarding the Schottky diodes!  I've read every page since page 1.  There was mention by a couple members that Schottky diodes would likely produce a lower voltage drop.  I guess I missed or forgot? Romero saying they didn't work well.  Or maybe this was higher power Schottky bridges? (which seem rare).  Anyway I was planning on using a bunch of small Schottky diodes to make bridges and even parallel a bunch to get a higher current rating.  I was thinking 16 or 20 per coil.  This would actually cost less than buying higher current Schottky diodes.  Can you think of a reason why the Schottky's would not work as well? 
   
  I think it may be good to build this device in a modular way so things can be easily swapped out to try all variables eventually for maximum output.