Mostly Permanent Magnet Motor with minimal Input Power

[tinman]

Here is the video on winding the first coil and what it looks like when finished.

I checked the DC resistance of each bifilar stands and they are 1.3 Ohm each. The coil winding program had calculated 2.7 Ohms as a single coil, so we are right on track. I don't have my Inductance meter with me but will have it on Thursday.

Link to video: https://www.youtube.com/watch?v=ULds78-fDoQ

Luc

Fantastic job on the coil Luc,and i can wait to see what kind of pull force this will give. Those are some nice magnets you have there as well.

[gotoluc]

@gotoluc

Great job - why no center taps?

wattsup

I think the combinations of 2 bifilar coils will be enough to test.

Luc

[gotoluc]

Thanks for the positive comments guys

I also can't wait to see what kind of pulling force an 8 times wider coil will do.
Even more, what will the extra tandem coil do?...  could it come to 16 times the pull force of my single 1" coil (500g @ 0.4 watt)?
Could be a world record for most pull force per watt?  if there is such a thing!

We shall see

Luc

[Khwartz]

Didier
It's a prony brake(dynamometer),not pony brake,and i never used one in my video. A prony brake is used to messure power and torque to get the horse power. Like i  said,i was getting the static torque force of the rotor in the motor,as Luc was getting from his MMM.

Yes, sorry, I am not English tongue, it is indeed of DYNAMOMETER meter I was talking about, and DYNAMOMETER is all about your PRONY BRAKE!

Your PRONY BRAKE is indeed a DYNAMOMETER which measures the TANGENTIAL FORCE at the SPECIFIC RADIUS you set the hook and screw on the disc.

Then, all what I have noticed remains: YOU STILL HAVE TO TAKE CARE OF THE RADIUS LENGH, to multiply the TANGENTIAL FORCE you read by it.

Torque [N.m] = F [N] × L [m].

I indeed didn't know about the prony brake system (even if it was a French citizen mate who invented it ^_^) but I pretty know now about this physics. Just go in the article of Wikipedia about prony brake and you will read this, brad:

"The difference between the two readings multiplied by the radius of the driven drum is equal to the torque."

http://en.wikipedia.org/wiki/De_Prony_brake

So, unless you have a system in your electronic PRONY BRAKE which permits to enterTHE VALUE OF THE RADIUS you set, it won't give you any TORQUE, even "STATIC", but only the FORCE [N]. But yes, if you care about the RADIUS LENGH and multiply it by the FORCE, you'll get indeed the "STATIC TORQUE".

As for the 1:1 comparison, would only work if you were taking the exact same radius than luc had used while testing on rotor disc, but surly not for example in his test of lienar force (without rotor system); but you probably know this already.

Regards.

[tinman]

Yes, sorry, I am not English tongue, it is indeed of DYNAMOMETER meter I was talking about, and DYNAMOMETER is all about your PRONY BRAKE!

Your PRONY BRAKE is indeed a DYNAMOMETER which measures the TANGENTIAL FORCE at the SPECIFIC RADIUS you set the hook and screw on the disc.

Then, all what I have noticed remains: YOU STILL HAVE TO TAKE CARE OF THE RADIUS LENGH, to multiply the TANGENTIAL FORCE you read by it.

Torque [N.m] = F [N] × L [m].

I indeed didn't know about the prony brake system (even if it was a French citizen mate who invented it ^_^) but I pretty know now about this physics. Just go in the article of Wikipedia about prony brake and you will read this, brad:

"The difference between the two readings multiplied by the radius of the driven drum is equal to the torque."

http://en.wikipedia.org/wiki/De_Prony_brake

So, unless you have a system in your electronic PRONY BRAKE which permits to enterTHE VALUE OF THE RADIUS you set, it won't give you any TORQUE, even "STATIC", but only the FORCE [N]. But yes, if you care about the RADIUS LENGH and multiply it by the FORCE, you'll get indeed the "STATIC TORQUE".

As for the 1:1 comparison, would only work if you were taking the exact same radius than luc had used while testing on rotor disc, but surly not for example in his test of lienar force (without rotor system); but you probably know this already.

Regards.

Hi Didier

Here is an efficiency test i carried out when UFO polotics decided he had an OU motor.This is an old school prony brake test. You are correct with the statements you made-no argument there.

https://www.youtube.com/watch?v=rkwRA28Y0dM&list=UUsLiBC2cL5GsZGLcj2rm-4w