Dear Dr.Jonkman
Yes, in order to know how the Generator torque affects edgewise bending of the blades, I enabled their respective DOF in the elastodyn file , which resulted in the addition of 6 states. The rows 13 and 14 show First time derivative of Variable speed generator and First time derivative of Drivetrain rotational-flexibility, respectively.
Row/ Rotating Frame? Description
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1 F ED 1st tower fore-aft bending mode DOF (internal DOF index = DOF_TFA1), m
2 F ED 1st tower side-to-side bending mode DOF (internal DOF index = DOF_TSS1), m
3 F ED Variable speed generator DOF (internal DOF index = DOF_GeAz), rad
4 F ED Drivetrain rotational-flexibility DOF (internal DOF index = DOF_DrTr), rad
5 T ED 1st flapwise bending-mode DOF of blade 1 (internal DOF index = DOF_BF(1,1)), m
6 T ED 1st flapwise bending-mode DOF of blade 2 (internal DOF index = DOF_BF(2,1)), m
7 T ED 1st flapwise bending-mode DOF of blade 3 (internal DOF index = DOF_BF(3,1)), m
8 T ED 1st edgewise bending-mode DOF of blade 1 (internal DOF index = DOF_BE(1,1)), m
9 T ED 1st edgewise bending-mode DOF of blade 2 (internal DOF index = DOF_BE(2,1)), m
10 T ED 1st edgewise bending-mode DOF of blade 3 (internal DOF index = DOF_BE(3,1)), m
11 F ED First time derivative of 1st tower fore-aft bending mode DOF (internal DOF index = DOF_TFA1), m/s
12 F ED First time derivative of 1st tower side-to-side bending mode DOF (internal DOF index = DOF_TSS1), m/s
13 F ED First time derivative of Variable speed generator DOF (internal DOF index = DOF_GeAz), rad/s
14 F ED First time derivative of Drivetrain rotational-flexibility DOF (internal DOF index = DOF_DrTr), rad/s
15 T ED First time derivative of 1st flapwise bending-mode DOF of blade 1 (internal DOF index = DOF_BF(1,1)), m/s
16 T ED First time derivative of 1st flapwise bending-mode DOF of blade 2 (internal DOF index = DOF_BF(2,1)), m/s
17 T ED First time derivative of 1st flapwise bending-mode DOF of blade 3 (internal DOF index = DOF_BF(3,1)), m/s
18 T ED First time derivative of 1st edgewise bending-mode DOF of blade 1 (internal DOF index = DOF_BE(1,1)), m/s
19 T ED First time derivative of 1st edgewise bending-mode DOF of blade 2 (internal DOF index = DOF_BE(2,1)), m/s
20 T ED First time derivative of 1st edgewise bending-mode DOF of blade 3 (internal DOF index = DOF_BE(3,1)), m/s
It is true that generator torque has more control sensitivity over these two states with respect to other state variables. However, its order of magnitude is e-4 , which is negligible compared to other control inputs such as 9th column (commulative blade pitch). Also, it has not any considerable effect on the edgewise bending of the blades(rows 18 to 20) and side-side bending of the tower(row 12).
So why is still reasonable to consider it as one of the control inputs?
Sincerely,
Hooman Asgari