It's hard to really explain how boats do it using only text and no good way to draw force diagrams.
I blasted through this video pretty quickly, but it appears to explain things well, including how it's possible for a sailboat to exceed wind speed: https://www.youtube.com/watch?v=jJtvGF8vZbE
The cart adds some moving parts, but I am pretty sure that all they're doing is ensuring that the blades' angle of attack is about the same as it would be for a sailboat's sail when it's sailing into the wind, by turning the propeller at an appropriate speed.
I blasted through this video pretty quickly, but it appears to explain things well, including how it's possible for a sailboat to exceed wind speed: https://www.youtube.com/watch?v=jJtvGF8vZbE
The cart adds some moving parts, but I am pretty sure that all they're doing is ensuring that the blades' angle of attack is about the same as it would be for a sailboat's sail when it's sailing into the wind, by turning the propeller at an appropriate speed.