O W O Flashcards
Name parts of a simple governor
Flyballs, oul pressure system, servomotor, pulot valve, distributing valve, relay valve
If a governor is regulating a single turbine does it require speed droop
No
Definition of a governor
An automatic attachment for controlling speed to a turnine
What is the function of the pilot valve in a hydraulic governor
Provides hydraulic force to the relay valve to open or close
What is sensing the change in speed
Flyballs/ball head
If we didn’t have a dashpot what would happen to
Overcorrecting/hunting, less stability
5% vs 2% speed droop, which would be more sensitive to the load on the grid. Would 5% sense it
2% more sensitive but 5% also senses it
Function of the auxiliary valve
Manually operating the gates in the event of emergency or for maintenance
4 safety devices
Overspeed, low oil pressure switch, float valve, nozzle deflector, auxiliary nozzles,
What do vibrating discs do
Improves sensitivity, keeps parts from sticking
Function of the restoring mechanisms in hydraulic governor
Recenter the pilot and relay valves
What kind of signal does PMG send to the motor
Electrical
Where is the speeder spring located
Next to flyballs
……… is used to control unit during startup, controlling the opening of the gates until the unit is up to normal speed
Gate limit mechanism
If needle calve and dashpot have been adjusted correctly, will it allow the small plunger yo recenter as the speed drifts back to normal?
Yes
What’s the relay valve positioned by
Pilot valve
Principle parts of governor oil pressure system
Pump, pressure tank, sump tank, piping
Sudden load increase will cause flyballs to go
Down
Sudden load increase causes upper floating level to go
Up
As pilot valve restoring linkage moves down, it moves the ……. down until the ports are closed
Pilot valve bushing
4 visual indications of oil deterioration
Sludge, varnish, dark cloudy color, dirty filter
Qualities of good governor oil
Lubricating, not break down, dissipates air, doesn’t precipitate solids
What would energize your shutdown solenoid
Any of the safety mechanisms
Overspeed, nozzle deflector, low oil pressure, erc
Dashpot provides
Delay to gates opening - hesitation
