Dear Mohamed,
Just a few comments:
- I would not expect that you’d use the generator-azimuth state when controlling rotor speed through collective pitch. It looks like you’ve zeroed out the effect in the nonlinear model, but not in the linear model.
- MBC and azimuth-averaging should eliminate the influence of the generator-azimuth state, which should then be removed from the linear model before use. This is discussed e.g. in the following forum topic: FAST linearization V7.
- The linear model represents perturbations about the operating point. So, I would not expect that you’d derive the pitch angle by adding 12pi/30K(2) to it.
- Minor comment, but the rated speed for the NREL 5-MW baseline wind turbine is 12.1 rpm, not 12 rpm.
I hope that helps.
Best regards,