Hello Everyone,

I am trying to integrate FAST with a DFIG generator as presented in [1]. As my first simulation I am very interested to duplicate the simulation of this report. I would really appreciate it if you could help me regarding the following two concerns of mine.

While FAST certification test 12 is used as the wind turbine model, MATLAB DFIG phasor model is used as the generator model in this report.

FAST certification test 12, represents WindPACT 1.5 MW wind turbine which uses a gear box with the ratio of 87.965. This gearbox speeds up the rotor speed of 20.463 rpm to the generator speed of 1800 rpm as described in [2].

MATLAB DFIG phasor model assumes a 3 pole-pair generator at 60HZ, while this WTG is normally operated between 30% slip (sub synchronous speed) and -30% slip (super synchronous speed) its maximum speed would be around 1200*1.3 = 1560 as described in [1].

The generator speed in the two subsystems are not compatible as one is 1800 and the other one at its maximum value is around 1560. I know the solution should be using a different gearbox with a different ratio. Hence, I am very interested to know more about the following questions in the simulation of [1].

My first question is what is the new redefined value for the gearbox ratio to solve the problem in [1]?

My second question is that if the gear box ratio is modified what are the (new) PI gains of the pitch control system for this simulation?

[1] Singh, Mohit, et al. Simulation for wind turbine generatorsâ€“with FAST and MATLAB-simulink modules. No. NREL/TP-5D00-59195. National Renewable Energy Lab.(NREL), Golden, CO (United States), 2014. (nrel.gov/docs/fy14osti/59195.pdf)

[2] Dykes, Katherine L., and Jennifer Rinker. Windpact reference wind turbines. No. NREL/TP-5000-67667. National Renewable Energy Lab.(NREL), Golden, CO (United States), 2018. (nrel.gov/docs/fy18osti/67667.pdf)

Thanks