Flux Gate Generator/simple design

[SkyWatcher]

Hi folks, i thought i would show a design ive been testing of a flux gate generator which unlike ecklins original uses the flux completion method as others have done. This design though is very simple and cheap to construct and has low magnetic drag and of course the anti-lentz behaviour associated with these flux switched designs and it seems to have very little counter effects to the generated voltage/current. I've been testing it with four bolts on the rotor but i am building a rotor with 16 bolts. the rotor uses steel bolts from the hardware store, 3-1/4" long 1/2" dia. and as shown in the cad pic i've posted has neo magnets in magenta color with the poles facing in attraction. initial results for the rotor with 4 bolts using just the one coil so far has given about 1Vac and when coil is shorted about 1Aac. coil is about .4ohms 18awg wire. those results arent too bad plus it has low natural ferromagnetic drag and would further decrease with bigger flywheel effect and higher speed. Any comments welcome.

peace love light

[gyula]

Hi SkyWatcher,

Thanks for this info, sounds very good.

While you still have only one coil with 4 bolts, I would suggest trying to close the magnetic path like I drew in your drawing.

This way you can test its effectivness in the induced power versus any drag increase (if any) with the yoke, with respect to your present unclosed magnetic path. By using the U shape yoke you simply increase the flux change via the coil core.

I do think that closing the flux of the magnets by such soft iron yokes in such setups, performance improves. Such modification should prove valuable even in Garry Stanley motor setup you are well aware of.

Regarding your bolts, they should be tested for eddy current losses because in most of the cases the different steel materials behave quite differently...

rgds, Gyula

[petersone]

I can't see how it gets round Mr Lenz,could you explain?

[Xenomorph]

@SkyWatcher:

Would it be possible for you to take a picture of your prototype?
Drawings are abstract sometimes.
Thanks and good luck with advancing the design!

[redeagle]

That's a great idea for using bolts. I do have a suggestion however. move the magnet on the neutral pole to the outside and put coils on that side as well.

What material is your mountings made out of?

[SkyWatcher]

Hi folks, thanks for the replies. Hi Gyula, Yes that could improve generation by providing a yoke and since i will have ultimately 8 coils it wouldnt be hard to do. Not sure if eddy currents will be much of an issue since no permanent magnet poles are alternating. Xenomorph, i will take a pic of it once the 16 bolt rotor is mounted because i took it apart, shouldnt take long. Hi Redeagle, yes i was thinking whats the cheapest and simplest and this is what i came up with, and i did try putting the neo on the right at the back of that bolt but less voltage generation although without a coil on that right bolt. But whats interesting is the neutral zone of the neo magnets falls around the left coils face which is why i think natural magnetic drag is lower, shifting of the bloch walls alone is worthy of study. the support structure and rotor are made of mdf tied together with threaded rod, the pic will help. As far as explaining why lentz law works for us in these flux switch designs theres plenty of information on the net that explains it better than i could but my take on it is that since its a passive ferromagnetic material in motion, the lentz repulsion that would exist on approach to a coil using a magnet or a coil does not apply to this design, in this case on approach lentz effect enhances attraction due to lentz law and enhances the departure attraction back which zeros out whereas with a rotating magnet or coil, lets say a rotating magnet approaches a coil we then have enhanced repulsion not attraction and therefore we have a non zero negative loss requiring more torque under generator load. Hope that helps your understanding.

peace love light

[SkyWatcher]

Hi folks, just finished the rotor, those nylon nuts are just used as spacers. still have to make new coil locations on stator structure. heres a pic.

peace love light