How does electro hydraulic governor functions?

governor has 3 modes of operation

1.SPEED CONTROL MODE-before sychronisation the governor runs in speed control mode.guide vanes open up and the turbine runs in the rated speed.when the governor gets connected to the grid that is when it gets synchronised then the speed control mode terminates.

2.OPENING MODE-load is increased in this mode and teh machine runs in the rated speed only.

3.POWER CONTROL MODE-it has two modes.joint controller and indivisual controller mode.in joint controller mode all the machine works all together and in the indivisual controller one setup point is given to the governor and the guide vanes vary accordingly