Does the whine increase with turbine RPM? If it does, then it is likely just the magnets passing the coils causing vibrations that are being transmitted through the tower, blades and other things.
If the whine stays at the same frequency, it is your controller making the turbine "sing" due to the PWM loading and unloading at it's operating frequency.
If your controller is just turning on and off (not PWM) the elements, the frequency should vary with RPM and that will be normal, but if it is excessive, I would look for several things.
Loose bolts, or weak (ie. lightweight) mountings. Heavier mountings for the stator and etc will be harder to vibrate and radiate noise. Lightweight ones will vibrate much easier and transmit that vibration through.
Hope you get it resolved. . .
Doug