Is it possible to scale down NREL 5MW Reference Wind Turbine to a 3MW machine only adjusting torque?
I assume that the aerodynamic project limits the tip speed to a certain magnitude, so that parameter would stay the same.
Would the dynamic behavior of the new wind turbine be unrealistic? What would be the main concerns regarding this change?
The torque fell from 43093.7 to 25856.6 kN.m.
I would not call what your proposing to do “scaling”, rather I’d call it “de-rating” the turbine or reducing the specific rating of the turbine. You could certainly change the controller to limit the power to 3-MW, but this would lead to a turbine that is overdesigned for the application (i.e. the structural components would be larger than they would need to be to carry the loads endured).
To properly “scale” the NREL 5-MW turbine to 3-MW, would require not only a change to the controller, but also a change to the turbine geometry and structural properties.
If I plan on having a same diameter wind turbine, what steps would you recommend to me to adjust its geometry?
I’m mainly worried about chordwise and twistwise changes, that would affect the production setup, as I’m not going to proceed to the use of structural information.
Thank you in advance.
I’m not sure I know enough about what you intend to do with this model to be able to comment. If you’re not concerned with the structural properties, then you are probably not concerned with aerodynamic optimization either. It is probably fine for your purposes then simply to limit the power to 3 MW only by changing the control parameters (leaving the aerodynamic and structural parameters unchanged).
I would use it as it is, but the parameters present an erratic behaviour, when compared to the default functioning.
As the specific power rating goes down, the nominal power is achieved a lot faster, what makes the rotor speed behaves in a strange manner, as you can see below.
I was hoping to find a relationship between power and chord/twist so I can reduce/change them accordingly to maintain a normal functioning.
You shouldn’t need to change the chord/twist to achieve a smoother Region 2 to Region 3 transition.
I’m not sure what it may be, but my guess is you have an improper setting in the control system that is causing the erratic behavior. What does “spcurve” mean?