Calculating the turning moments for a passive wind turbine under yaw

[james6008]

Hi

I have been looking for some simple equations that describe the turning moments on the rotor as wind direction changes. I know this can be relatively complex but I am looking for simplified equations. Has anyone got any information where I can find these? The wind turbine is a small horizontal axis passive turbine with a tail vane. Focus here is on the rotor.

 

[UltrafastPED]

Try "Analysis of the passive yaw mechanism of small horizontal-axis wind turbines"

http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=5335837&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D5335837

This article goes over the controls systems, but leaves out the equations:
http://mragheb.com/NPRE 475 Wind Power Systems/Control of Wind Turbines.pdf

Also see http://www.hindawi.com/journals/tswj/2014/516394/

 

[james6008]

Thanks for the links :)

The second article mentions
"The typical form of such systems consists of a roller bearing connecting the tower and the nacelle, along with a tail fin mounted on the nacelle which aims to apply an apt torque to the nacelle so as to turn the turbine rotor to the direction of wind."

I have searched everywhere but I can not find an equation that let's me calculate this torque in simplistic terms. If someone has come across it before please let me know.