I have somewhat of a problem, and I need some help. I'm an electrical engineer, but I don't deal with high power applications. I'm designing an electromagnetic stirrer to go on a cold plate for an anodization system. No one seems to sell anything like it with the cooling power I need, so I'm looking at doing it myself. The cooling unit is thermoelectric, and I'd like to have the specimen (a beaker with chemicals). I'd like to design a nice low-voltage 3phase induction motor, and use the magnetic stirring bar as the rotor inside the beaker. I was in doubt that this would work, since there's no shaft to keep the bar magnet in place, but since then I've found out that cole-parmer and a few others manurfacture these things and brag that there are no moving parts.
My problem is that I need to design either a single-phase induction motor, using a capacitor design much like you mentioned above to get the phase separation, or I could buy a converter from 1PH/DC/3PH to power the windings. Since the load is nothing more than 100-500mL of solution, the torque requirements are negligible. I'd like to make it variable speed also. Does anyone sell a drive like this? Does anyone have any good ideas on how I might convert the power?