Dear Jason.

I have two questions about the unit.

First, I am calculating the gain value in blade pitch control using below equation.

Kp=(2*(Drivetrain Inertia)*(rated low-speed shaft rotational speed)*(damping ration)*(natural frequency))/(Gearbox ratio*-Sensitivity Power to Pitch)

Could you let me know the exact unit of rated low-speed shaft rotational speed in the above equation? (either rpm or rad/sec)

Second, I got the power sensitivity to blade pitch as below from FAST linearization.

I got the sensitivity -7.485E+03 from D-Trnsmt Matrix. Then what is the exact unit for the sensitivity? (either kw/deg or kw/rad)

Order of Control Inputs in Linearized State Matrices:

Column 1 = rotor collective blade pitch (rad) 4.62861E-02 op

Order of Input Wind Disturbances in Linearized State Matrices:

None selected

Order of Output Measurements in Linearized State Matrices:

Row 1 = WindVxi (m/sec)

Row 2 = RotPwr (kW)

Row 3 = GenPwr (kW)

Row 4 = BldPitch1 (deg)

Row 5 = RotSpeed (rpm)

Row 6 = GenSpeed (rpm)

Row 7 = GenTq (kN-m)

Linearized State Matrices:

--------- Azimuth = 0.00 deg (with respect to AzimB1Up = 0.00 deg) ---------

op State | op | A - State | B - Input

Derivativs | States | Matrix | Matrix

0.000E+00 | 0.000E+00 | 0.000E+00 1.000E+00 | 0.000E+00

0.000E+00 | 0.000E+00 | -1.093E+03 -3.832E+00 | -9.485E-02

##
op Output | This colmn | C - Output | D - Trnsmt

Measurmnts | is blank | Matrix | Matrix

1.200E+01 | | 0.000E+00 0.000E+00 | 0.000E+00

3.335E+03 | | -1.892E+06 -6.723E+03 | -7.485E+03

0.000E+00 | | 0.000E+00 0.000E+00 | 0.000E+00

2.652E+00 | | 0.000E+00 0.000E+00 | 5.730E+01

1.700E+01 | | 0.000E+00 0.000E+00 | 0.000E+00

1.530E+03 | | 0.000E+00 0.000E+00 | 0.000E+00

0.000E+00 | | 0.000E+00 0.000E+00 | 0.000E+00

Thank you.

HyoungChul Kim.