OC3 Phase IV - LC 5.1 Controller Question

Wind & Water Controls
1

Hello all!

I’m probably misreading something here, so I’ll ask before beating my head against the wall. In LC 5.1 of Phase IV of the OC3 the NREL-FAST simulation results present the pitch of blade 1 (BldPitch1) as a constant 0 degrees. Is that correct? Wasn’t the blade pitch controller turned on for this simulation?

Thanks!
Sean Quallen

2

Dear Sean,

Yes, the pitch controller was turned on for LC 5.1 of OC3 Phase IV, but this LC involves steady hub-height winds of 8 m/s, which is well below rated wind speed. The operational pitch controller only commands angles different from zero when operating at rated power.

Best regards,

3

Jason,

As always, thanks!

Sean Quallen

4

Apologies if this question is either in an inappropriate section or has been asked before but remains unfound by myself.

I note from the OC3 phase IV hywind spar section of the ‘IEA Wind Task 23’ report, that in Table 17, Load 5.3 was for turbulent winds with a mean speed of 18m/s.

Would anyone know if the results for this test are available anywhere, preferably as raw simulation results as is the case for OC4 semi, but if not within a paper showing platform motion responses?

5

Dear Dawn,

All of the OC3 results (from the final revision of each Phase) are available here: drive.google.com/drive/folders/ … 3RkZ3FHVlE.

Best regards,