You failed to tell us what model wind turbine you are talking about. I know from personal eperience that Air Marine
types can generate vibrations even with good blades. The source is that the sockets in the hub allow a good deal of angular slop, and it is common to not have the blades equally spaced, and thus a dynamic unbalance is generated.
I was able to cure this by starting with one blade, centering it as best I could in the socket. Then, using a tape measure, I checked the distance between blade tips very carefully, and with a lot of trial and error, got them perfectly even before locking the screws down hard. Made a huge difference. The sanding
helps too, but more with noise
than vibration IME.
Of course, you may have a different design, and all that was a waste of words... it is good to be pretty specific about equipment