I hat to be the bearer of bad news, but chances are that if any of the mosfets are blown, then the whole gate drive circuitry will likely be fried as well. Unless you happen to have some spare parts kicking around then it'll probably be cheaper to just replace the controller than to go blindly replacing parts without knowing a rough idea of what's wrong...
If, however, you can figure out for sure that a particular part is fried, then it should be fairly easy to replace one or two parts...
Good luck,
Pete
So true. Its getting to the point where I'd like to see the circuits deintergrated and each step of the controller built to a modular design with relevant fuses installed. So if you blow say the fet module you can replace it with a new board etc.
Just like the "old" PC.
Edit:
Just think you could upgrade to the latest digital phase angle V4000 board with phase angle advancing system for better torque and speed yada yada, lose the need for planetary gearing and lose the weight. LOL, that would be awesome.