Hi gww
Short reply, on my way out soon.
For 48v, a 36Pole 2X6C should work fine, but cut in may be a little high, it depends on your blades. See
http://www.thebackshed.com/windmill/FPRewire.asp for details. Then add a cap doubler to increase low wind power. At a guess, try 560uF 350V caps back to back. They can be expensive, so price around.
Or you could try a staggered stator, see
http://www.thebackshed.com/windmill/articles/StaggeredStators.asp. Say a 1X5C and a 1X7C, would give you a earlier cut in, but still good power once the wind picks up. It does mean a extra set of rectifiers though, as you need to rectify the two sides separately.
Yep the cap doubler circuits can be hard to follow, they were drawn by Gordon to use single phase rectifiers, and there are un-necessary connections shown. If you look at this thread of my cap doubler on a OEM windmill, it may make more sense. Basically its just a 3 phase voltage doubler, on a 48v system
http://www.thebackshed.com/forum/forum_posts.asp?TID=6812&PN=1. The cap doubler on that windmill can pass over 4 amps before the main rectifier reaches cut in speed. Low wind performance is good, and I see over 700 watts in high winds, furling holds it back above that.
Personally I would try the staggered stator first. Its cheaper and easy to undo if you later wanted to try the cap doubler.
Glenn