Ferrite Design

I've been using Neomags to build turbines based on Huge Piggots original recipe with good results.

The last 3m used (24) 2"x1"x.5" N42 magnets ($17.50 each), with a total cost (here in Canada) of $420, just for magnets. That's a lot of change and certainly impacts the total cost of the project.

Ferrite magnets on the other hand are cheap, $1 for the same size as the neo. With less magnetic flux I'll need to use more magnets, but even going to 96 magnets (each magnet will be 2"x2"x.5" or 2"x2"x1" depending on testing) will cost $300 less.

Some of the criteria is that it must use the standard 3m frame, have a narrow stator (in order to close the air gap), be 300mm or less in diameter, and operate at 24v.

The first test uses 80 turns of 14awg, triangular shape, with pin centres of 40mm. This should allow me to keep the diameter of the mag rotors to 300mm. The smaller diameter will allow me to close the air gap without fears of contact between the mag rotors and the stator.


Ferrite project coil. 80 turns, 14AWG wire, 40mm pin centers

 The pic below shows the coils mounted to a soldering board. The board is easy to make, and takes less time then trying to keep the coils in position while soldering. Now when the soldering is done and the coils removed they're in perfect position.

Coils mounted to a soldering board. Makes soldering so much easier.

 Below is a pic of the ferrite dimensions compared to a neo stator. As well as being smaller in diameter it's thinner as well. Thickness of the ferrite is 15.3mm, and the neo version is 16.1mm. Again, this will help me to close the air gap, helping push power up. The added bonus is that the new stator will also use less epoxy in the casting process, again helping to lower costs.

Comparison of the ferrite stator to the 800w neo stator.

 Resistance for the ferrite stator is .8ohms per phase. Intending to be operated at 24v, this should give me approx 30amps, and 720w. IF I exceed 500w I'll be happy.

Nine coils set out prior to soldering.

A ferrite design putting out 500w is perfect for turbines in the remote areas of Mexico. Plenty of power with a good site, and a lower cost of materials.
As I continue with this build I'll update the posts with numbers from testing.