Why is generator power an input into the SFunc.mex?

Dear OpenFAST team,

Is the generator power fed into the Simulink-FAST interface a part of some of the turbine dynamics?



Dear Bartosz,

Really only for output purposes. The various torque control and generator models in FAST / OpenFAST return as output both the generator torque (needed for the dynamics calculations in the FAST / OpenFAST) and the electrical power, the latter of which is only for reference and can be written to the output file. This same purpose of the torque control and generator models was transferred to the Simulink interface.

Best regards,

Thank you!

Dear Everyone,

I am confused by the same question. I am trying to implement a torque controller on Simulink, but I don’t know what to put at the power input since the power should be calculated through OpenFAST using the controlled torque. When I place 5MW as a reference at the power input, the GenPwr resulted is the same fixed value, as if the torque controller is not taken into consideration. Is it possible to avoid giving it a power input and compute the GenPwr through OpenFAST thanks to the generator torque? If yes, how to do it?

Sorry for the inconvinience

Kindest regards


Dear Younes,

If you specify that torque control is implemented in Simulink (VSContrl = 4), then OpenFAST will not compute the generator power internally, because it is assumed that if the user needs it as an output, the user will calculate it within the Simulink model. If you want to model the generator power very simply (as it would have been implemented in OpenFAST), you can implement it in the Simulink model by multiplying the generator torque by the generator speed and a generator efficiency.

Best regards,

Dear Jason,

Thank you so much for the help and clarifications.

Kindest regards