# Tip Speed Ratio

Dear All
Hi
While controlling a wind turbine, individuals consider a control strategy according to which they can achieve maximum power captured by
that, so-called Maximum Power Point Tracking at optimum point for TSR and, in turn, Cp, but my purpose is to study the response
of the system in all region of TSR: for example 3 < land < 15. The problem is that, as I control the system through generator torque I could not
reach the area where landa > 8. Actually, I mean under any circumstances, even if I do not want to reach optimum point of TSR it stops at this
point while not increasing, but there is no problem to reach the landa < 8.

You kind answer would be highly appreciated.
Sincerely

Dear Amirhossein,

I’m not sure I fully understand your issue, but could your problem be related to what is discussed in the following forum topic: http://forums.nrel.gov/t/linearisation-trim/628/2?

Best regards,

Dear Dr Jonkman
I am using 5MW WT model embedded in FASTV8 and I have not found the term “Trimcase”; On the other hand,
my aim is not to make linearization. I provide generator and controller using simulink, and the only problem
is that I cannot reach TSR > TSR_opt (7.5-8). I need to have system response while TSR is changing from
3 to 15.

Yours sincerely

Dear Amirhossein,

I wasn’t assuming you want to perform a linearization analysis, but was simply referring you to the discussion of the physics. I.e. a simple proportional-only controller aiming to regulate rotor speed based on speed error will become unstable if the desired speed is less than the TSR that results in maximum aerodynamic torque coefficient.

Again, I’m not sure if this discussion applies to your case on not, but perhaps?

Best regards,

Dear Dr Jonkamn
Thanks
Since you discussed linearization, I confused that it relates to that, but now I understand.
Anyway. the issue is that I need to have a simulation while TSR is sweeping the interval [3:15] rather than
only regulating to its optimum point; I considered constant wind to simplify. On the other hand, I changed
desired speed and TSR intentionally.
For the interval 1 < TSR < 8, there is no problem, but for TSR > 8 , it does not work.

Best Regards

Dear Amirhossein,

OK, I’m not sure then. Hopefully someone else can comment.

Best regards,