Tuning ROSCO controller with DISCON.IN

Dear all,

I have a question regarding the “floating feedback” control strategy. I’m generating some customized DISCON.IN files using the ROSCO toolbox, with each file featuring different closed-loop frequencies and damping values for the pitch controller (zeta_pc and omega_pc).

My question is:

If I set Fl_Mode: 0, zeta_pc: 1.0, and omega_pc: 0.2 in the turbine’s YAML file, I will generate a DISCON.IN file where the gains of the pitch controller are calculated to ensure the dynamic performance is as specified (zeta_pc = 1.0, omega_pc = 0.2).

However, if I set Fl_Mode: 1 while keeping the same zeta_pc and omega_pc values, will I achieve different dynamic performance? If the answer is yes, how can I calculate the new closed loop frequency and damping?

I hope my question is clear.

Best regards,
Marco