Dear Jiaping.Cui,
My guess is you are receiving the error about position = (0,0,0) because the tower aerodynamic analysis nodes in the AeroDyn v15 input file for the MIT/NREL TLP model extend down to ground level. To solve this problem, extend the FAST.Farm domain lower (to ground level), increase the lowest-most tower node in the AeroDyn v15 input file, or disable tower aerodynamics altogether.
Regarding the expected values of the rotor speed and blade-pitch angles for the NREL 5-MW baseline wind turbine as a function of mean hub-height wind speed, please see the following forum topic: NREL 5-MW reference turbine - #7 by Jason.Jonkman.
Best regards,