I was thinking about the source motor or generator needed to do this.
Thinking the best approach would be an alternator.
Unless you can start with a good 3 phase you will not have an effective system meaning it will be an inefficient generator motor and thats like a waste of power.
Here's an interesting link that tells a little.
It would be nice to find some more helpfull links and information, but that seems real hard to come by.
http://www.nojolt.com/how-to-build-a-rotary-phase-converter.shtml