I've found the gens trip if the RPM surges. I'm not sure if there is an over-speed disconnect or not.
I encountered some mild turbulence where the engine RPM surged, and then icing conditions. A bit later I noticed the gen had tripped, though there was no reason for it to have done (that I saw).
While the engine audibly surged, the engine instruments didn't really support this (prop RPM did fluctuate slightly but remained in the green).
I did get popping from the turbine (intake icing?). I powered back, switched on all the de-ice systems, and held on.
I had deliberately flown into icing to see what happens. I've never had a situation like that in the sim where I was actually wondering if I'd make it out the other side.
I also lost the gen once sometime around landing or shortly afterwards. Again, not sure why, and didn't see anything that indicated it should trip.
I now keep an eye on the voltages and the gen bus during icing and other engine events to check it is still connected.