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/* Wind Turbine Control Systems */
| A method of controlling the speed of a wind turbine by varying the orientation, or pitch, of the blades, and thereby altering its aerodynamics and efficiency.
[[Image:pitch.jpg|thumb|center|175px|Fig 16(a) [http://zone.ni.com/devzone/cda/tut/p/id/8189 Pitch control]]]
Source:[http://www.moog.com/markets/energy/wind-turbines/blade-pitch-control/ sourceBlade Pitch Control]
| The rotation of horizontal axis wind turbine around its tower to orient the turbine in upwind or down wind direction.
[[Image:Yaw.jpg|thumb|center|175px||Fig 16(b) [http://zone.ni.com/devzone/cda/tut/p/id/8189 Yaw control]]]
Source:[http://zone.ni.com/devzone/cda/tut/p/id/8189 sourceWind Turbine Control Methods]
|Stall control works by increasing the angle at which the relative wind strikes the blades (angle of attack). As the wind speed increases drag force on the blade increase and lift force gets reduces, thus finally reduces the speed of turbine.A fully stalled turbine blade, when stopped, has the flat side of the blade facing directly into the wind. Compare with furling.
Source:[http://www.windmeup.org/2008/03/stall-control-basics.html sourceStall-control basics]
|As the aerodynamic torque control changes, rotor speed changes. it changes the output power frequency. A frequency converter is connected in between generator and the network to maintain generator power constant.
Source[[Media:windenergycontrol.pdf|sourceWind Energy Control]]
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