Wind turbine initial conditions

[Abhinay.Goga]

Dear Jason and all,

Please correct me, if I'm wrong. According to my understanding, for every DLC the user assigns initial conditions (here mainly, Blade pitch and RPM ) to reduce the transient period of the simulations and to help the the controller find the stability earlier as possible.

For the same DLC (assume power production with wind gust) with different wind speeds, is it reasonable to assign different initial conditions, even though I'm assigning sufficient transient time? (lets say 100s) The simulation starts with considerable vibrations and in-time, around 90s, reaches reasonably stable position. But once the gust starts, the simulations behaves not as expected. Changing the initial conditions, changes this behavior.

Does the initial conditions have effect on the simulation, even after settling?
Any guidance is much appreciated.

Thanks and regards

[Jason.Jonkman]

Dear Abhinay,

The initial transients should eventually die out and not have an effect on the future simulation outcome. But depending on the control system you are using, from my experience, if proper initial conditions are not set, the controller may be initialized improperly and not be able to recover. To avoid such problems with initialization of the controller, and to minimize the start-up transient, I would always recommend initializing the rotor speed and blade pitch to their expected values for the given mean hub-height wind speed.

Best regards,

[Abhinay.Goga]

Dear Jason,

Once again thankful for your time and valuable insights.