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HAWCStab2 changelog
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Under development/Still to be tested in full
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- Dynamic inflow.
- More flexible handling of external systems.
- N-bladed wind turbine stability analysis.
- Adaptive trailing edge flaps.
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Version 2.9 (rev. 1048) - 19/MAY/2016 - LARH,LEOB
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- Computation of operating point for "storm-control"/de-rating operation
- CT and CP output added at radial computational points (.ind output).
- Bug fix for saving open loop matrices with quasi steady aero-dyna-
  mics enabled.
- Dynamic inflow implemented (in BETA!): Frozen wake (default), quasi-steady and
  dynamic inflow.
- Automatically adding extra element in body before first node to have
  a node close root of body.
- Possibility to calculate optimal operation points for fixed
  pitch. This can e.g. be used in run-away flutter analysis.
- Input forces can now be applied to external systems.
- Added new controller "basic_dtu_we_controller" for full wind speed
  range closed-loop stability analysis.
- Output sensors 'momentvec' and 'forcevec' now have units in kNm and
  kN, respectively, to match HAWC2.
- Output sensor for rotor speed has reversed sign in C-matrix to match
  HAWC2.
- Added 'steady_state_convergence_limits' option to change convergence settings.
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Version 2.8 (rev. 863) - 13/DEC/2013 - LARH
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- Improved aero-servo-elastic modal analysis and sorting.
- Fixed bug for HS2pid with rotation speed conversion between rpm and
  and rad/s.
- Fixed bug for calculation of input matrix (B). This affects transfer
  functions, state space matrices and closed-loop analysis.
- Changed video codec from xvid to cvid. Now Creation of videos should
  be possible on all computers.
- Fixed forward whirling being animated as backward whirling and vice
  versa.
- Minor bug fix for quasi-steady dynamic stall stability analysis.
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Version 2.7 (rev. 734) - 21/OCT/2013 - LARH
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- Fixed bug introduced in version 2.5 that gave minor steady state
  errors.
- Fixed bug introduced in version 2.3 that gave wrong low frequency 
  Bode plots and controller tuning due to wrong aerodynamic gradients.
- Fixed bug introduced in version 2.3 that divided B-matrix w.r.t 
  pitch with 3. 
- Added 'constant_power' line in 'controller_tuning' block: 
  0 = constant torque and 1 = constant power.
- Changed calculation of inflow angle written to result files. Now it 
  the same as the one used by the internal calculations.
- Fixed bug with ct that was not fixed in V.2.6.
- When a new controller tuning is calculated, this will be used by the
  closed-loop analysis instead of the values given by the command line
  'pi_pitch_controller'
- Steady state values for N-bladed wind turbines can now be calcu-
  lated. Controller tuning for N-bladed collective pitch controllers
  is also possible now.
- Write-out of closed-loop matrices is now possible from the menu.
- Added new criteria for sorting modes.
- Added new controller gain scheduling method
- Changed dialog box when performing aeroelastic and aero-servo-
  elastic modal analysis.
- Minor tweak in implementation of damping_posdef routine.
- Added HAWC2S commands:
  'compute_structural_modal_analysis', 
  'compute_steady_states': it is the same as 'steady_state' but it 
    doesn't save anything.
  'compute_stability_analysis', 'compute_aeroservoelastic', 
  'compute_controller_input', 'save_ol_matrices', 
  'save_ol_matrices_all', 'save_beam_data', 'save_blade_geometry', 
  'save_aero_point_data', 'save_profile_coeffs', 'save_power', 
  'save_induction'
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Version 2.6 (rev. 569) - 23/AUG/2013 - LARH
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- Changed write-out of "Save modal amplitudes" for blade only. Now a 
  phase angle close to 0 deg. is ensured and the sign of the amplitude
  is corrected accordingly. I.e. amplitudes can now be negative.
- Fixed bug where torsional mode shape was not written correctly to
  text file
- Fixed bug where gear ratio was not read in the htc file.
- Started development of code to handle 2,3,4,... bladed turbines.
- [N.B. See V.2.7] Fixed bug with ct in BEM calculations, this should
  only have minor implications at above rated wind speeds. 
- Added support for external systems. So far they are attached to the
  bottom node of the tower. This can be used for e.g. jackets modeled
  as super elements.
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Version 2.5 (rev. 512) - 08/AUG/2013 - LARH
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- Critical bug fix. Previous release version removed from website and
  replaced by current one.
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Version 2.5 (rev. 499) - 07/AUG/2013 - LARH
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- Added new save open-loop matrices options. Also added steady state 
  output values of selected sensors.
- In  the operational_data block the prvs_turbine option has reversed 
  logics, e.g. 0 = stall regulated, 1 = pitch regulated. This is 
  opposite of previous version, but more logical.
- Changed calcalation of inflow angle written to result files.
- Various bug fixes.
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Version 2.4 (rev. 380) - 10/JUN/2013 - LARH
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- Added 64 bit version of HS2 to enable memory expensive calculations.
- Added Rayleigh damping model similar to HAWC2 with mass and stiff-
  ness proportional damping terms 'mx my mz kx ky kz'. N.B. 'damp' 
  and 'damp_pos' might be disagreeing on the order of 'kx' and 'ky' 
  in HAWC2. HAWCStab2 uses the 'damp' convention.
- Added command line program H2Spid.exe which is a command line 
  version of HAWCStab2.exe with reduced functionality only able to 
  calculate PI controller gains assuming rigid blades.
- Log files are now saved as 'filename'.htc
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Version 2.3 (rev. 203) - 29/JAN/2013 - MHHA
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- Added command line program HAWC2S.exe which is a command line 
  version of HAWCStab2.exe.
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Version 2.2 (rev. 181) -  6/JUL/2012 - MHHA
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- ...
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Version 2.1 (rev. 131) -  2/FEB/2012 - MHHA
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- ...