Is it advisable to preselect Frame 9E Gas Turbine at 100MW ?

Is it advisable to preselect Frame 9E Gas Turbine at 100MW ?
We dont know about plant/facility /loads configuration

Is that unit is connected to large infinite grid ...or other kind of utility/facility/process

According to my experience the best way to operate Frame9E is suitable with National grid code /dispatching mode..

For a facility it will be different operationg /loads mode such ...

Again we wait to have more datas for give a advise...
 
The Frame 9E Gas Turbine is connected to the National Grid. The Station has two gas turbines and one steam turbine. The gas turbines are 110MW Base Load rated. At certain times of the day the grid operator (system control centre) request the units loads to be reduced due to excess generation in the system. This is how come the unit at times is preselected at 100MW.
 
The Frame 9E Gas Turbine is connected to the National Grid. The Station has two gas turbines and one steam turbine. The gas turbines are 110MW Base Load rated. At certain times of the day the grid operator (system control centre) request the units loads to be reduced due to excess generation in the system. This is how come the unit at times is preselected at 100MW.
Okay
Well I see no bad reason to operate this unit in kind configuration.. As much as the Plant Operators know how to react on transients phase...
What about droop mode scheme.. In this station..
 
Pre-Selected Load Control is NOT a good way to operate GE-design heavy duty gas turbines.

If the unit is being operated at Base Load (the BASE LOAD target/button on the "main" Start-up Display is usually orange to signify BASE LOAD is active), all the operator need do is start clicking on the LOWER SPEED/LOAD target/button to start reducing load. At first (if BASE LOAD is active) it will seem like nothing is happening, but it is, and after several clicks the load will actually start decreasing (the BASE LOAD active indication will be extinguished as soon as LOWER SPEED/LOAD is clicked on the first time). As the load approaches 100 MW, slow down the rate of clicking and when it's approximately 100 MW (+/- 1 MW or so) stop clicking on LOWER SPEED/LOAD.

While it's impossible to believe for most people, the load won't change. It will still have that little "bounce" (up and down)--but it will probably be less of a "bounce" than if Pre-Selected Load Control is enabled and active! Try it--if you dare. Most operators and operations supervisors are 100% ABSOLUTELY CERTAIN that if Pre-Selected Load Control is NOT enabled and active the unit will simply drift willy-nilly to just any and every load between 0 MW and Base Load--which is simply NOT TRUE.

Now, why is Pre-Selected Load Control a bad choice for operating a GE-design heavy duty gas turbine (yes--EVERY GE-design heavy duty gas turbine)? Well, unless the Mark* is equipped with PFR (Primary Frequency Response) (which ALSO has to be manually enabled! when Pre-Selected Load Control is manually enabled!) if the grid frequency starts to change or become unstable the Mark* will FIGHT the tendency of Droop Speed Control to try to help support grid stability by changing load--because Pre-Selected Load Control (without PFR) will try to maintain a constant load, AND it will do so by jerking the load around, up and down, which only makes the grid frequency/stability worse!!! Pre-Selected Load Control IS NOT a way of maintaining a stable, steady load during grid frequency disturbances, and, it only makes the grid stability worse--for everyone. During a grid frequency disturbance it is normal AND DESIRABLE to have the load fluctuate as grid frequency fluctuates to try to help stabilize (yes--stabilize) the grid and get it back to normal quicker.

It is becoming MORE and MORE and MORE common for grid operators and regulators to ban the use of things like Pre-Selected Load Control. The term they like to use is "Free Governor Mode"--which is the same thing as Droop Speed Control. PFR (Primary Frequency Response)--an option that GE likes to get paid to include or add to their Mark* to correct a "small" oversight with Pre-Selected Load Control (the one that makes it FIGHT frequency excursions) is one way--albeit expensive--of being able to operate a GE-design heavy duty gas turbine in Pre-Selected Load Control AND allow it to, more or less, respond to grid frequency disturbances as gensets should. But, most grid operators/regulators have to have this explained to them.

To simply answer the question of whether or not it's okay to use Pre-Selected Load Control to set a load reference (setpoint) and have it automatically maintain that reference--yes; it's acceptable, as long as the grid operators/regulators allow it. If the National Grid in your part of the world is prone to grid frequency disturbances, it's really NOT a good way to operate the unit.

Finally, it's very common for the deadband/hysteresis adjustment of Pre-Selected Load Control to be incorrect. How do you know if this is the case? When operating with Pre-Selected Load Control active you will see the load continually go above and below the reference/setpoint, and you will see constant flashing of the RAISE- and LOWER SPEED/LOAD target/buttons to try to get the load back to the reference, but it will just keep overshooting. As noted above, simply operating in Droop Speed Control without Pre-Selected Load Control active is just about the best way to maintain a setpoint, and the unit WILL NOT drift wantonly just anywhere. Try it--you'll like it!!!
 
I have seen units like Frame 9e operating well on preselected load when it's good tuned & grid stability OK..
But now you saying that Dispatching is asking to reduce to 100MW...So how one can achieve that.. By using preselected load.. Function
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