1. FUNCTIONS OF THE GOVERNING SYSTEM
To contain the speed rise within acceptable limits if the unit gets disconnected from load.
To regulate the steam control valve position and hence load generated.
To control the initial run up and synchronization of the machine
To assist in matching the power generated to that demanded by responding to the network frequency changes.

2. SALENT FEATURES OF 200 MW KWU TURBINE GOVERNING SYSTEM
KWU 200 mw turbine is a throttle governed machine.
Two governors, electro-hydraulic and hydraulic are incorporated. Both the governors are connected in parallel.
Only one governor can be selected at a time through the process of hydraulic minimum selection.
The control valve opening depends on secondary oil pressure and there is a definite relationship between the opening of HP control valve and IP control valve.
Between 40 to 200 mw the turbine load is varied by changing the HP control valve throttling alone.

3. HYDRAULIC GOVERNOR SALENT FEATURES
Hydraulic governor is having only one control loop called speed controller.
HG consists of mechanical arrangement of spring and bellow.
Machine speed is measured and indicated as primary oil pressure.
Range of speed control is rpm.
Speed regulation range (droop) of HG is 7% and can not be changed while the machine is running.
HG acts as a back-up to the EHG.
HG can not be isolated mechanically like EHG and HG is considered to be the primary governor of the KWU turbine

4. ELECTRO-HYDRAULIC GOVERNOR SALENT FEATURES
EHG consists of three control loops for speed, load and pressure.
EHG optimizes the turbine life by conservative operation with the aid of TSE.
Faster response and precise frequency control.
Actual speed of the turbine is measured by using hall probes
Range of speed control is wider (0-3210) rpm.
Speed regulation (Droop) can be changed from 2.5% to 8% in a step of 0.5% even when the machine runs on load.The usual setting of droop in EHG is 5%.
EHG can be mechanically isolated by closing the secondary oil line from the local.

5. DIFFERENT OILS USED IN KWU TURBINE
Control oil (source oil)
Signal oil (LP bypass operation)
Auxiliary start-up oil
Start-up oil
Auxiliary trip oil
Trip oil
Auxiliary secondary oil
secondary oil
Test oil
Primary oil
Lub oil
Jacking oil

6. GOVERNING SYSTEM DEVICES
Remote trip solenoids
Turbine trip gear (Main trip valve)
Starting and load limiting device
Speeder gear
Auxiliary follow-up piston
Follow-up piston
Hydraulic amplifier
Electro-hydraulic convertor
Sequence trimming device
Solenoid for load sheeding relay
Extaction valve relay

7. REMOTE TRIP SOLENOIDS

9. TURBINE TRIP GEAR

10. AUXILIARY TRIP
FLUID
DRAIN

11. MAIN TRIP VALVE DRAIN TRIP OIL CONTROL OIL AUXILIARY AUXILIARY
START-UP OIL
MAIN TRIP VALVE