ROSCO Controller for NREL 5MW Turbine

[SKMechatronicEngineering]

Hi,

I am using the ROSCO controller with the 5MW NREL turbine.
I want to add individual pitch control, thus I am looking to the rosco controller.

So far I am simply used the DISCON.In found at Examples/Test_Cases/NREL-5MW in the ROSCO github.
Is that a good starting points? Does anyone knows how the controller gains and gain scheduling tables found here have been established?

As IPC is not part of the DISCON.in found in the examples, I have manually tuned the Ki and Kp gains of the IPC. The remaining values I did not change.

!------- INDIVIDUAL PITCH CONTROL -----------------------------------------
9.120000  11.400000  ! IPC_Vramp		- Start and end wind speeds for cut-in ramp function. First entry: IPC inactive, second entry: IPC fully active. [m/s]
2                    ! IPC_SatMode		- IPC Saturation method (0 - no saturation (except by PC_MinPit), 1 - saturate by PS_BldPitchMin, 2 - saturate sotfly (full IPC cycle) by PC_MinPit, 3 - saturate softly by PS_BldPitchMin)
0.3                  ! IPC_IntSat		- Integrator saturation (maximum signal amplitude contribution to pitch from IPC), [rad]
2e-10 0.000e+00 ! IPC_KP			- Proportional gain for the individual pitch controller: first parameter for 1P reductions, second for 2P reductions, [-]
5e-10 0.000e+00 ! IPC_KI			- Integral gain for the individual pitch controller: first parameter for 1P reductions, second for 2P reductions, [-]
0.000000  0.000000  ! IPC_aziOffset		- Phase offset added to the azimuth angle for the individual pitch controller, [rad]. 
0.0                 ! IPC_CornerFreqAct - Corner frequency of the first-order actuators model, to induce a phase lag in the IPC signal {0: Disable}, [rad/s]

Simulations are running smoothly, and IPC is working so to speak.

However, the goal of my simulations is too establish some reasonable pitch loads, i.e. both pitch rate and moments.
Naturally the tuning of the controller is important in that regards.

I wonder if anybody else tried to use the rosco controller with IPC in combination with the 5MW NREL?
How did you tune your controller gains especially for the IPC part?

Basically I just want to know if my tuning is completely off.

Best regards
Søren

[dzalkind]

Hi Søren,

Your gains seem reasonable. My process is to sweep the gains with the goal of reducing blade root loads. If the gains become too high, the IPC will be unstable, so it's good to have a safe margin from that point.

I hope this helps.

Best, Dan

[SKMechatronicEngineering]

Thanks.

Seems like a good strategy 👍