fatal error in OC3 hywind

Please help me, thank you. I was going to decrese the Additional linear stiffness of yaw motion (98340000) in OC3 hywind certtest, in order to match and reproduce the yaw motion measured in the model test(larger than 6 degrees). The matter is when I did this , the fatal error always occurred as shown in following picture. I wonder why it didn’t work, when the yaw motion is too high? And what should I do? Thank you for your attention.

Baoxuan. Wang.
Aborting FAST.txt (4.61 KB)

Dear Baoxuan Wang,

We have experienced platform-yaw instability issues for models with too little yaw stiffness, e.g., as discussed in the following forum topic: http://forums.nrel.gov/t/floating-platform-motions/995/2.

Best regards,