Are you looking for a variable pitch depending on the wind speed? If so, you should research variable pitch propellers from the aviation industry. You would need a logic board to read the speed of the propeller and actuate the change in pitch to maintain the speed you want within a specified range.
The variable pitch for high wind periods is critical for survival reasons, but entertained the idea of opposing motor/generators coupled with planetary gear set as in hybrid vehicle (Prius) for wind power. Seems like it would offer some good control of available wind power to loads for rpm control on both ends. Good luck with project, small to medium wind power needs some development help.