I got a stator and flywheel and my problem is that the stator has a 4 wires coming from the stator and I don't have a schematic. There is a green wire which is screwed to ground. The rest, a yellow, a white and a red with blue stripped that all appear to go to different coils.

I'm thinking these are three phases of an ac stator? My thought is to have the pedals spinning a shaft that the flywheel is tied to. Then I'd vary the votage going to each phase (dc voltage) which would produce a magnetic field and resistance to the pedaling.

On Tue, Mar 26, 2013 at 3:44 PM, Rob Butts <r DOT butts2 AT gmail DOT com> wrote:

I do understand how the magnetic field varies in the road bike trainer and kind of understand the eddy current braking theory. I did get an eight coil stator and flywheel that I thought I'd experiment with. In the see also section of the eddy current brake wiki page there is a link for Telma retarders and towards the bottom of that page a section describing an electric retarder which sounds exactly what I need and what I can use this $14 stator and flywheel for. I think I just have to gear the speed of the flywheel as high as I can which at this point is 5 to 1.

On Mon, Mar 25, 2013 at 10:13 AM, John Griessen <john AT ecosensory DOT com> wrote:

On 03/24/2013 03:58 PM, Rob Butts wrote:

One plastic disc is fixed and the opposing plastic disk is allowed to rotate 30 degrees providing the variable magnetic field and
variable resistance. I have not been able to simulate the resistance I believe because I'm not providing the same rotational
velocity of the aluminum disc.

Sounds like the out of alignment of the discs makes the field vary from weak to strong.
To have strong fields, each magnet needs to be straight across, (through the aluminum disc),
from another with same polarity direction. Then induced currents flowing in circles around the strong field area
counter subsequent motion by a force of their own. I've never quite grasped how that force stays local
to any place in the aluminum plate though...perhaps inertia of electrons? Else moving the path of the high
eddying current is more resistive than the eddy path? It's all so circular! I feel like researching
and reading about it instead of doing my taxes...

What do you mean by simulate? What velocity can you get?

Some decent velocity is needed for small inexpensive magnets. I've seen a demo
of eddy current braking done with a pendulum hung plate, then a slotted plate
for comparison, where the opposing magnets were very massive and with iron looping
around to make a complete magnetic circle path with two short gaps, ( where the aluminum
plate moved). It would slow the pendulum in one stroke by 4/5ths. It must have weighed
80 lbs.

An alternator will need velocity also. Bicycle gearing can get you velocity.