Role of Turbulence Intensity (TI) in SCADA Data for North Calibration

[Emmaant]

Hello!

I'm calibrating my SCADA data using simulated data from FLORIS, specifically for north calibration. However, I noticed that my SCADA dataset doesn’t have a column named "ti", and I can’t find where this column is actually used in the calibration process, but in the class bias_estimation it gives an error when that column doesn't exist.

I do have "ti_000" to "ti_015" for each turbine in my SCADA data, but these don't seem to be used. In contrast, I can see that "ws" (wind speed) and "wd" (wind direction) are explicitly calculated using upstream turbines, but I can't find a similar process for "ti". Even though there might be a function for it in the repository, I haven’t found it being applied during calibration.

My question is: Is "ti" actually used in the calibration process, or does it just need to exist as a column? If it's required but not used, can I simply set it to a constant value?

[Bartdoekemeijer]

Hey Emma,

Indeed, it's not used in the northing calibration process. The northing calibration process just aligns the largest dips in the energy ratios from FLORIS with those in the SCADA data. A different ti will make those dips deeper/shallower, but it doesn't shift them to the left or right. Hence, ti has very little impact on the actual northing bias calibration, and that's why it is not used.

From the top of my mind, the reason for having a ti column in the SCADA is to use it to calculate the FLORIS predictions for every timestep. Setting it as a constant value in your df is totally fine, and something I do too!

[Emmaant]

Super! Thanks for a clear and fast reply!