Hello everyone,
I am currently attempting to reproduce a derating control strategy for a wind turbine, as outlined in Younes Oudich’s article titled “Wind Turbine Fatigue Load Analysis for Derating Control Strategies Aimed at Grid Balancing.” The control feedback for this strategy (specifically when the turbine is operating in zone 2) is presented in the following figure
I have implemented the model in Simulink, using the FAST function to simulate the wind turbine. However, the rotor speed and the power extracted in my simulation seem to closely mirror the fluctuations of the wind, following each dynamic change. This contrasts with the much smoother curves depicted in the article.
These are my curves :
Here is the ones from the article :
I feel that the turbine’s inertia may not be adequately represented in my model. I would appreciate any guidance on how to properly account for this or suggestions on what aspects of my Simulink model could be improved.
Thank you in advance for your insights.
Best regards,
Sarah Gilles
Hi Sarah,
The inertia will affect the generator speed signal response. Based on your plots, it looks reasonable to me. You could try starting with the NREL-5MW model inertia and scaling that to your model.
The other component of the power signal is the torque command (GenTq). Showing that would help. Based on the generator speed signal, I’m guessing it follows the wind speed signal very closely.
From the block diagram you showed, I’m guessing that the V_eff is your wind speed signal, and that gets translated into a torque command that follows the wind speed signal. In a real controller, V_eff would be a wind speed estimate; that would mirror the fluctuations of the wind, but at a lower frequency.
I hope this helps. Please let us know if you have any further questions.
Best, Dan
Hi @Daniel.Zalkind,
Thank you for your answer. This figure shows the wind speed, the generator speed, the generator torque as well as the generator power. You can see that the generator torque follows the wind speed signal dynamics.
On the second figure, here is my Simulink control model :
Indeed, for the V_eff, I take the signal directly from the wind speed signal. Should I add a low-pass filter to my model ?
(2) I also have an other question. By comparing the GenSpeed signal direclty coming from OpenFast and the generator speed calculated from the RotSpeed signal (multiplied by the gearbox ratio to have the gen speed), I observerd some differences as seen in this figure :
What are the reasons for these differences?
Kind regards,
Sarah Gilles
