DEAR ALL,

PLEASE FIND ENCLOSED THE "U" COIL I MADE TODAY (Yesterday now! -JM).

I WAS ABLE TO GET 10 W OUT OF THE HC COILS w/ ACCELERATION.
10 W - HC COILS ONLY - STOPS THE SYSTEM.

TOMORROW I PLAN ON MAKING ANOTHER VERSION AND LOOKING TO INCREASE MY 10 W TO 20 W WITH AN ADDITIONAL COIL.

ALSO HERE IS A PHOTO OF A NEW GRINDER MOTOR w/ SPEED CONTROL BUILT IN - IT IS A DELTA GR 275.

CHEERS
Thane

Quote from: CRANKYpants on June 04, 2008, 07:10:31 PM

WE DON'T WANT TO CONVINCE YOU - WE MAY END UP (GASP) RESPECTING YOU OR SOMETHING EQUALLY HIDEOUS LIKE HAVING TO BE NICE TO YOU ETC.

I think you guys might have hit the theoretical ceiling with Larry's 'semi agree'...



PS The Pittsburg Penguins looked fantastic with mascara and snot running down their crushed faces.  Thus ends the 2007/2008 season, and my hockey trash talk.  Sigh.

I have just got my new rotor up and running, I am using customwood disks to hold the magnets, i have a few more to make so I can try different magnet configs but now I have the first one as a pattern it's all very easy.

I tried it with my old stators and the results are slightly worse maybe? than with the rotor Thane sent but that's the difference between 6 magnets and 18, I will soon try Thanes 3 stack.

I have 3 other MOT's so I should be set there, however I don't have a ton of suited wire so I may not split and rewind more than one or 2 coils at most initially and try the other as is.

Quote from: OUman on June 04, 2008, 07:38:41 AM
Do you think that writing bold-caps "obvious" next to your statements somehow gives them greater scientific merit?

All the acceleration and deceleration stuff is, of course, obvious - it's easy to see and to measure and it's great Youtube material. But the issue is that it's not the acceleration/deceleration itself that matters. It's the power flows. I know it sounds like a broken record but that's the point that you're persistently ignoring.

There is a way, though, to do it by the acceleration/deceleration method and still be measuring power reliably. A few posts up I referred to a method that can actually use deceleration as a defensible means of measuring the power flow in the generator. The reason it works is that the prime mover is completely disconnected during the measurement phase and so cannot be responsible for any of the power flows, nor for any of the changes in speed - so whatever happens is necessarily done by the generator. It was originally A22's idea and it's bullet-proof as far as I can see. If you can demonstrate OU with that method you'll certainly have me convinced.

I tried a deceleration experiment again with the new rotor, the result is still inconclusive.
The decelerations seem a bit slowed maybe (just did 1 test each with and without coils shorted, though the variation from test to test may be greater than the difference), but a few % but not much.
And the cogging torque is a lot reduced so it seems entirely that by reducing that is the cause for another 8% or so revolutions in the most recent test with the new rotor. (yes, I really should do more than one of each)

IMO and based on the best evidence the acceleration comes from the motor.

addition:

Ok, I did a few more tests.

rpm 2870-2875 (sometimes it goes right to 2875 other time it won't budge above 2870)

open   shorted (in later tests only shorted while rotor is at decent speed)
1103   1196
1042   1052
1054   1110
1052   1134
1069   1099

I ran more open circuit tests than shorted, I removed a string of open circuit tests in a row where it was under 1,000 (as low as 977) revolutions since they are outside the normal results for open circuit and were all in a row.

Since in the later tests I disconnected the HV coil at lower rpm's to reduce the higher cogging torque effect, maybe the fact that the results aren't lower for the shorted means it worked because more energy should seemingly be lost, but even at higher speeds cogging torque creates vibration that is reduced by shorting, also hysteresis and eddy current losses in the stator and rotor are reduced by shorting.

To me those results seem too small to account for the acceleration noted when the motor is running, that can turn a deceleration into a relatively robust acceleration but I feel unconvinced either way by these results.

Quote from: aether22 on June 05, 2008, 04:44:33 AM
IMO and based on the best evidence the acceleration comes from the motor.

best evidence ? 

Hmmm, you might be right, since most motors are built to accelerate from stop to go !   

Cheers and KneeDeep