Jeff, a 3-coil/4-magnet ratio will give you a 3-phase output. A 4-phase machine (whatever that would look like) would require 4 rectifiers instead of only 3, a 2-phase machine would have more ripple/flutter, so 3-phase is smoother.
Getting 200 RPM's from a 12 MPH wind seems to me to be a result of the blades, which you have stated is not your teams concern.
As you probably already know, Watts are the sum of Volts X Amps, so its very important what voltage you want to generate. I have to assume that your sponsor wants to end up with a product that can be sold to the public, so I will further assume that you will not want 12 volts.
If you want the power to pass through a smart charger into a battery pack, and then convert the stored power through an inverter into 110-120 VAC, I will assume for the sake of obtaining affordable and reliable off-the-shelf components that you will offer the sponsor a 24-volt and/or a 48-volt generator.
One-Kw would be:
A. 24V at 42 Amps
B. 48V at 21 Amps
Instead of Googling the site, I recommend scanning through the last two years of "wind" postings, and copy every paragraph that lists something like "I used X number of wraps of Y gauge wire and got 24/48-volts at Z RPM's". 10% more or fewer RPM's will usually result in 10% more or fewer volts, so you can pro-rate that coil (using math, for a graphchart) at near 200 RPM's.
You should be able to make a useable rough chart as a result. As the RPM's rise, the volts will also rise until it reaches the cut-in point when the volts are finally slightly higher than the battery voltage. Any further increase in RPM's will translate into rising amps. Too many amps and the stator will overheat, so the machine should furl away from the wind before that point.
The machines the Dans have made and documented are as good as anyone here knows how to produce. Find the specs from several different sizes, and copy the magnet rotors of the machine that is closest to your needs (6-coil/8-magnets per rotor, 9C/12M, etc).
If the design RPM is set, and you need to double the magnet speed to reach your voltage goals, you have to double the circumference and the number of poles. A bigger diameter PMA will need a bigger prop. Too big a prop and the RPM's drop, too small and there's not enough torque. If Flux says you need a 30', I believe him.
After you've made the rotors, you can make one test coil and set it between the rotors for a bench test. Since you want to make some Amps at 200 RPM, you will want to rise to your cut-in voltage at a lower RPM, I'll guess 160 RPM?
Research Star/Wye or Delta phase connection. I "think" Star is popular because it produces more volts at a lower RPM. I also "think" each coil only has to make 1/3rd of the final volts (yes?). IF this is true, your test coil should make either 8 or 16 volts at 160 RPM's (does that sound right?) for a 24 or 48 volt machine.
Sorry to be so fuzzy about the last part. I would have researched it more, but, when it comes time for me to build, I'm just going to copy a machine that fits my new site wind profile.
If your test coil voltage is too low at 160 RPM, wind a new coil with more wraps of thinner wire. If its too high, use fewer wraps of thicker wire.
