'Rose-Tinted Lenz' Generator...

[tinman]

Hi Gyula,
  I have some experimental results. I tested two cases, using the same magnet & (shop-bought) ferrite-core coil. Diagrams attached below.
Results measured on oscilloscope. All values are Peak-to-Peak voltages.

Case #1: Standard generator configuration - with magnet passing over the coil.
I put a lino tile (1mm) over the coil, so the magnet wouldn't stick too hard. Then just moved it back & forth as fast as I could.
Max Volts: 2.6v

Case #2: Magnet and coil stuck between two 5mm mild steel plates. A third plate is used to simulate the rotor.
I put the lino tile over the 'rotor' plate, and moved it towards & away as fast as poss...
Max Volts: 1.6v
With 2 identical coils in series between the plates, Max Volts: 2.8v

So - it's possible to get a reasonable voltage out using this arrangement. It is less than the standard config, but not by too much.

'Bucking' coils...

I got this duelling / bucking coils' business totally wrong like a muppet, lol. The two coils act just like one bigger one, and there's no positive feedback. Maybe there could be if they were in separate circuits, at different phase angles or something, I'm not sure. Maybe there is an arrangement where you can get loads to drive themselves. This isn't it though.

Cogging...

Cogging isn't too hard to overcome, and my understanding is that in theory it doesn't add much friction - as sum attraction is zero. I thought I'd mention it though. I quite like the Muller/Romero idea of simply having one extra rotor piece - but I guess it means you need a separate rectifier on each pair of coils.

I think the key to making this generator OU is to
a) minimise the flux from the coils that's 'visible' to the rotor.
b) Make use of the coil's flux to (help) drive the rotor - via a separate mechanism.

Will post more in this in a bit...

Hi Tim
Unfortunatly the net attraction wont be zero,and lenz law will still apply.
When your steel (or ferrite)core on the rotor starts to leave the magnet/core arangment,the coil will induce a like field within the core to that of the magnet's.This will increase the strength of each magnet pole,and pull harder back on your rotor segment as it leave's the magnet.
So once you load the coil,lenz law will once again show up.

[tim123]

Hi Tinman, yes, I know - I said that in the first post:
"... in fact - there is a mechanism for a reaction against the rotor:
- As the rotor approaches the stator, the coils cancel out the PM's field - thus no attraction on approach
- As the rotor leaves the stator, the coils reinforce the PM's field - thus extra attraction on exit."

The point is: I think the part of the core near the PM will have a relatively constant flux - due to the (partial) saturation of the iron by the PM, whereas the part of the core away from the PM, the 'extension', will have the full variation of flux. As shown in the diagrams RTL-5.gif, and RTL-7.gif...

[tinman]

Hi Tinman, yes, I know - I said that in the first post:
"... in fact - there is a mechanism for a reaction against the rotor:
- As the rotor approaches the stator, the coils cancel out the PM's field - thus no attraction on approach
- As the rotor leaves the stator, the coils reinforce the PM's field - thus extra attraction on exit."

The point is: I think the part of the core near the PM will have a relatively constant flux - due to the (partial) saturation of the iron by the PM, whereas the part of the core away from the PM, the 'extension', will have the full variation of flux. As shown in the diagrams RTL-5.gif, and RTL-7.gif...

Well as i have found,the best way to find out is to build it and try it. Only then will you have the answers you seek.
You have many great idea's,and they deserve to be put into working devices. I know for one,that i will be trying that other design you came up with.

Brad

[tim123]

Thanks Brad, I hope to come up with a few more too, hopefully at least one of them will be OU.

[tinman]

Maybe use one of them design's as a pulse motor insted,and join in on the pulse motor build off.