1-Reduce its sensitivity by adjusting drop at Governer setting and observe the responce.
2-Redue integral action, if PID incorporated.
3-Check MW feed back comming to control, complete loop
4-Service or replace linkage
5-Check total span movement of valve with signal range, calibrate if...
You can apply protection to your bus, for under/over voltage and frequency simply.
Only in condition of fault at one line your system load will shift to other line, the system should not trip in this case.
Tell your operational requirement to the protection engineer. or you can call me at...
Shuting down the mover is safe, to avoide damage in motoring case, like in breaker failure situation. The reverse power protection should have a dual action i.e trip breaker and shut down fuel and air intake to mover too.
Usually reverse power not frequently operates, if your operator is...