Cut-Out Wind Speed / Control in Fast v8

Wind & Water Computer-Aided Engineering Software Tools
1

Dear Jason,

I am running FAST v8 (w/ AeroDyn v15) to simulate a P-v-curve, with pitch-controlled blades.
My goal is as follows: If the rated windspeed is reached, the power should remain constant (through blade-pitching) until the windspeed reaches the cut-out speed.
The plot should look like the blue curve (as shown in the ServoDyn Workshop PDF):

P-V-curve Reference.png

My question is:
Does the controller in FAST v8 “shut down” the turbine automatically if the cut-out wind speed is reached, so that the power drops down to 0 as in the plot?
I tried the bladed-style DLL (“DISCON_win32.dll”) in ServoDyn and left the input file as default, but the turbine still continues to run after the cut-out speed, which should be 25 m/s. I am using a slighlty modified “Test19” 5MW NREL model from the CertTest folder (with every DOF off, except Generator, Drivetrain and Yaw , no tower influences and a hubheight windfile).

Here is the plot of my P-t-curve, where I increased the wind from 0-100s until it reached 11.4 m/s, then left the windspeed constant until 200 s, then increased it again. The curve gets very weird at the end.

P-t-curve Matlab.png
P-t-curve Matlab.png576×512 27.5 KB

Thank you in advance for any help!

Best Regards,
Randi

2

Dear Randi,

The baseline controller of the NREL 5-MW turbine supplied with Test19 applies only to normal operation; it does not include control logic for start-up and shut-down scenarios. The NREL 5-MW specifications report explains the functionality of the baseline controller in detail: nrel.gov/docs/fy09osti/38060.pdf. You’ll have to modify the controller or manually impose the shut-down.

Best regards,

3

Dear Jason,

Thank you for the clarification!

Best regards,
Randi