Mostly Permanent Magnet Motor with minimal Input Power

[i_ron]

According to my calculation you gained 0.17J in potential energy and used 1.185J electrically so 6.9% efficiency in that case. But this test alone is not really good on its own due to joule heating and wasted inductive energy.

Thanks broli ! still that is better than 3%, lol


I didn't mention, that test was with steel end plates.


Ron

[gotoluc]

Hi everyone,

sorry for not getting back sooner but I have very limited internet access.
Thank you for all your input. I will try to reply to most and then will be back in another 2 days.

Luc

[gotoluc]

Interesting Stuff Luc, did you make those laminations yourself?

Yes, I took apart some UPS transformers, used the wire to make coils and the Laminations to make all this stuff you see.

Luc

[gotoluc]

Hi Luc.

I've stuck the maths in a spreadsheet for you.

Here is the Microsoft Excel version :

http://internut.webspace.virginmedia.com/Lucmotor%20Efficiency%20Test%20-%20Capacitor%20Version.xls

Here is the Open Office version :

http://internut.webspace.virginmedia.com/Lucmotor%20Efficiency%20Test%20-%20Capacitor%20Version.ods


All the best,

DC.

Thanks DC for taking the time to make this

Luc

[gotoluc]

Im not sure I agree with the first statement above.  The magnets applied to the top and bottom of the core are same poles facing the core. If you know how typical speaker technology, the magnets fields are not inline with the voice coil. They are "directed" to be from the inner side of the coil to the outer of the coils circumference.

So Lucs inner core with N facing in on top and on the bottom, those are repelling fields.
Those fields N will be directed outward from the central core. All along that center core are north fields outward, perpendicular to the core, looping back around to the south poles at the top and bottom.

Then you add the outer cores amd the path for thos outward N fields become more concentrated because the loop cannot expand outwards to get to the south. The outer cores help contain and direct the fields, very similar to a speaker voice coil and magnet structure.

So basically Luc, If you want to enhance your knowledge greatly with your project, study speaker design. Or more to the point, high power sub woofer design.

There are special speaker designs that will interest you also is a planar speaker design with a spiral coil on a diaphragm between 2 flat disc magnets with lots of tiny holes for the air pressure(sound wave) to pass through the front and the rear. Pioneer made a very nice set of headphones using the planar method years ago. And the disk magnets were same pole facing in, like your setup. The bass reproduction from those headphones was UnReal.

So dont think about the coil being attracted and repelled by the magnets at the top and bottom, but how the coil reacts to the fields escaping outward all along the central core.
The coils powered interaction to those fields lines perpendicular to the core is what is really going on. If you remove the core, or replace it with a non magnetic one, your output will not be better. It will be an inefficient speaker in comparison.

And, I dont believe there is any ring happening when Luc discharges the cap into the coil. It actually is taking a good amount of time for it to totally discharge from high to low then nadda.  Electrolytic caps dont provide a good oscillating environment anyways.
Try it, its not very good at all.

Luc,  look into the speaker and high power subwoofer design that can be found. There is not as much as you might think. Not for people like us anyways. There is a program out there that allows you to design speakers in a cad environment. You can design the cores, magnets and the rest any way you want. I have to look the name up as it was years ago that I have looked into the subject.   Google books has some good old stuff also. ;]

here is a sub woofer design I had made near 15 years ago. The key features were shallow depth with longer throw, elimination of the lower spider suspension by utilizing a second inverse rubber surround of which helps to keep the cone and coil on axis.

Earthquake audio company got it out before I did with the dual rubber surround suspension eliminating the spider and reducing depth. 

The magnets in the magnet housing are N facing inwards to the center and S outward to the outer core. Alumapro conquered that part of it soon after.

I just couldnt get the funding to break it out at the time. too little too late

Very interesting Mags

I'll let it soak in for a while.

Nice speaker design man

Thanks for sharing your work and experience

Luc