Muller Dynamo for experimentalists

[LtBolo]

Yes. I'm sure the 1N4007s are faster than a high current bridge. Several folks have suggested a lower forward bias voltage, but that isn't necessarily true. Faster, I'm sure of.

[nul-points]

 
apologies guys, i've been out having a life this evening!

(well, band practice, anyway - almost a life) 

Ron, i guess i didn't take a trace of the waveform when the coil pair was opposed ,thinking it was incorrect - hah!  that'll teach me

and my PC scope is in use for a few days now on a logging task - don't think i'll be able to setup the test rig again til later next week 

so - from memory, i'm pretty sure that it had a similar look both to Romero's and woopy's first traces showing one coil reversal

i was getting reasonable output with a 10 ohm load - it could have been 50% or more of the pk-pk with the coils in 'addition' - i seem to remember that the w/f was locked solid, but that could be because i had the two coils mounted on a hand held yoke so that i could move them along a radial to determine what was the best o/p i could get


i've just cut out my stator plates and now need to drill for core positions and rotor shaft access, and then somehow get them and the DC motor fixed securely on my baseplate (a bread board!)

when i have a stable platform i can repeat my handheld coil tests, but i reckon someone else will have been able to give us all more info by then

nice teamwork guys - i was just about to give up posting after my experience on the MD thread

keep it flowing
np


http://docsfreelunch.blogspot.com

[EMdevices]

Update:


I managed to digitize and extract data points from RomeroUK's output waveform (just the first cycle) and than I corrected for the small negative slope seen across all his waveform (perhaps due to 60 Hz interference), and also centered the waveform, so that the begining coincides with the end, so it's exactly one cycle period.   I extracted 71 data points.   

Now it's time for curve fitting, and FFTs and than integration,  time to fire up Matlab.


EM

[i_ron]

Ron,


I'm assuming that you all have the same dimentions for your coils, magnets and rotor, etc.., just like Romero's dynamo.     Also we don't know the SPEED at which his waveform was taken.

EM

EM,

1104 RPM (approx) different core material, somaloy, different coil size, different  wire, but still my grandfathers ax

Ron

[nul-points]

 
...just seen that EM asked if my tests were done with bias mag - they were - all details of my test setup are posted above, near where i first suggested that Romero's trace indicated that coil pair was in opposition

thanks
np


http://docsfreelunch.blogspot.com