There are lots of ways to do this given enough time to experiment. The way I would try is with 3 relays. These would be 3 Pole, Single throw "ice cube" relay in the appropriate amperage These are easy to get, thats why I would chose them. Also a centrifugal switch that you could get out of a 120 VAC motor that is not working. The spring tension will need adjusted so that it operates at the correct time. This switch needs to be an normally open switch (NO). Along with the switch you will also need the slip rings to make all the necessary connections at the location of the switch. If a slip ring is not installed the wires to the switch on the rotor of the generator will be twisted off.
I have never wired anything up like this, but "on paper" this is how I see to make it work. Look at the pic's for more information.
I have included a DWG (2010) file with these same drawings. DWG is an Autocad file, but Draftsight also uses these files. If you don't have Autocad download Draftsight, it is free. http://www.3ds.com/products/draftsight/download-draftsight/?xtor=SEC-6-GOO--[old]-S-[draftsight]&gclid=CKShq-DXibcCFZBcMgodZncAnQ
Some of you may wonder why I used 3 relays, this is because you need to completely isolate the Y wiring from the Delta wiring. If you do not then there will be a "dead short" condition and you will not get any usable energy to the rectifier bridge. This is the simplest, or easiest way I can come up with to make the switch between Y and Delta without more components and more expense.
Depending where you mount this control will make some difference in cost of the project. Wire is expensive, so my suggestion would be to build this in an outdoor weather tight enclosure and mount it as close to the wind powered generator as possible, or reasonable. I say this because you need to run all 6 coil wires down the pole to the controls, plus the 2 wires from the centrifugal switch, making 8 wires. The ideal place would be right under the generator, this uses the least amount of wire. In reality I would mount the box about head high on the support structure. It will use more wire from the generator to the box, but if there is a problem I would not have to get to the top of the structure, or take it down to work on it. There will only be the 2 DC wires to run to your setup. 2 wires are a lot cheaper to run then 8 all the way back to your charging station.