IEA15MW reference turbine spinning faster than max rotor speed

Hi Jason/NREL,

I downloaded the OpenFAST model for IEA 15MW turbine… GitHub - IEAWindTask37/IEA-15-240-RWT: 15MW reference wind turbine repository developed in conjunction with IEA Wind (Latest release v1.1.3 link).

I am using OpenFAST Version 3.3.0 binaries… Releases · OpenFAST/openfast · GitHub.

I only made some minor adjustments to the template model:

  • Platform DOFs set to false in Elastodyn file
  • HWindSpeed set to 15m/s in InflowWind file
  • TMax set to 250s in the main FST file

Steady state rotor speed is 11.3rpm. I was expecting it to be about 7.55rpm.

Any idea on what could be happening in the OpenFAST model?

Best regards,

Quick follow up to yesterday’s question. I downloaded other versions of OpenFAST and found that OpenFAST 2.5.0 binaries are compatible with the IEA 15MW turbine Version 1.0 files.

The older version correctly predicts steady-state rotor speed of 7.5rpm as expected. There is some fluctuation at the start, perhaps due to the initial rotor speed of 0.5rpm, which I deliberately set to a low value in order to test the robustness of the control system.

My conclusion is that there is some issue with the OpenFAST 3.3.0 binaries, or perhaps the controller which is shipped with this version.

I have not tried the latest version, OpenFAST 3.4.1, because the latest IEA 15MW turbine files don’t seem to be compatible with this version.

I can work with OpenFAST 2.5.0 for the moment. But I would be interested to hear if anyone has any comments on my questions/conclusions.

Hello Aengus,
thanks for using the forum.
I couldn’t replicate your error, but I’ve verified that the model of the IEA15 in the develop branch runs correctly in openfast 3.4.1 + ROSCO v2.6.0 .
Please access the IEA15 model here GitHub - IEAWindTask37/IEA-15-240-RWT at develop and compile/download the ROSCO controller here GitHub - NREL/ROSCO: A Reference Open Source Controller for Wind Turbines
Please let me know if this helps.
Best regards,

Hello Pietro,

Many thanks for your reply.

I am still having difficulty, even with OpenFAST 3.4.1, the develop IEA turbine model, and ROSCO 2.6.0.

I suspect there may be some pilot error on my part, particularly given that you have been unable to replicate the behaviour which I described. I will ask a colleague to review/QA my model.

Kind regards,