Homopolar generator idea

[seaad]

An AC variant.

[seaad]

A new suggestion.

[F6FLT]

A new suggestion.

It will work, 100% sure (I presume the magnets present opposite poles).
A probably more efficient method is to remove the central wheel and use two counter-rotating disk-magnets touching each other by their rims and having same poles. I wrote "probably" because their weak point is that they repel each other.

[seaad]

Yes this was my first thought also but the magnets polarity [your way] makes it near impossible to make them touch each other, because they repeal themselves extremely strongly sideways and radially.
If we force them to touch each other, I presume that the braking action in the axis bearings will be  greater than as in my suggestion above.
I wanted to avoid a build with these hateful brushes at the rim.

Regards Arne

[F6FLT]

Hi Arne,

The repulsion will not result in a slowdown, because it is not a torque that is applied against rotation. We have a linear force in the plane of the magnets, and if it is not perfectly balanced, which will certainly happen, there will be also a torque tending to rotate the plane of the discs. A solid mechanical system can solve the problem. An easy way would be to fix the magnets in front of rotating conductive discs and only the discs rotate.
The possible demagnetization of opposing magnets may remain a problem.
With intermediate wheels, we increase mechanical losses, and electrical losses since we increase the number of contacts, so not sure if the method is better. I don't think so.