Methods and systems for thrust-based turbine wake control
A method, system, and apparatus for improving wind harvest efficiency comprises: a wind turbine, a processor, and a computer-usable medium embodying computer code, said computer-usable medium being coupled to said processor, said computer code comprising non-transitory instruction media executable by said processor configured for: setting a desired location range of a wind wake with a controller, determining an error signal indicative of a difference between a currently measured cross-stream thrust component of wind and an optimal cross-stream thrust component of wind, adjusting a speed of a rotor associated with the wind turbine according to the error signal, and confining a real-time position of the wind wake to the desired location range of the wind wake.
1 . A system for wind turbine optimization comprising:
a processor; and
a computer-usable medium embodying computer code, said computer-usable medium being coupled to said processor, said computer code comprising non-transitory instruction media executable by said processor configured for:
calibrating a controller wherein calibrating the controller comprises directly measuring wake trajectory deviations by measuring velocity time-series signal spectral energy amplitude changes at periods equivalent to one or more rotations obtained from experiments on models in wind tunnels;
setting a desired location range of a wind wake with the controller;
determining an error signal;
adjusting a speed of a rotor associated with a wind turbine according to the error signal in order to minimize the error signal; and
confining a real-time position of the wind wake to the desired location range of the wind wake by minimizing the error signal.
2 . The system of claim 1 further comprising:
generating a look up table of a yaw misalignment angle, a rotor speed, and cross-stream thrust.
3 . The system of claim 2 wherein calibrating the controller further comprises:
calibrating the controller with the look up table.
4 . The system of claim 3 wherein the look up table is associated with a specific turbine design.
5 . The system of claim 4 further comprising prescribing controller variables wherein the controller variables comprise at least one of:
pitch;
yaw; and
speed.
6 . The system of claim 1 wherein the error signal comprises:
a difference between a currently measured cross-stream thrust component of wind and an optimal cross-stream thrust component of wind.
7 . The system of claim 6 further comprising:
readjusting the rotor speed, to minimize the difference between the currently measured cross-stream thrust component of wind and the optimal cross-stream thrust component of wind.
8 . The system of claim 1 wherein setting the desired location range of a wind wake with a controller further comprises:
selecting the desired location range to maximize efficiency of a wind farm comprising a plurality of wind turbines.
9 . A wind turbine optimization method comprising:
calibrating a controller wherein calibrating the controller comprises directly measuring wake trajectory deviations by measuring velocity time-series signal spectral energy amplitude changes at periods equivalent to one or more rotations obtained from experiments on models in wind tunnels;
setting a desired location range of a wind wake with a controller;
determining an error signal in order to minimize the error signal;
adjusting a speed of a rotor associated with a wind turbine according to the error signal; and
confining a real-time position of the wind wake to the desired location range of the wind wake by minimizing the error signal.
10 . The method of claim 9 further comprising:
generating a look up table of a yaw misalignment angle, a rotor speed, and cross-stream thrust.
11 . The method of claim 10 wherein calibrating the controller further comprises:
calibrating the controller with the look up table.
12 . The method of claim 10 further comprising:
prescribing controller variables in response to changes in cross-stream thrust using unsupervised machine learning, wherein the controller variables comprise at least one of:
pitch;
yaw; and
speed.
13 . The method of claim 9 wherein the error signal comprises:
a difference between a currently measured cross-stream thrust component of wind and an optimal cross-stream thrust component of wind.
14 . The method of claim 13 further comprising:
readjusting rotor speed to minimize the difference between the currently measured cross-stream thrust component of wind and the optimal cross-stream thrust component of wind.
15 . The method of claim 14 further comprising:
mitigating wake meander from a set trajectory, the wake meander resulting from instantaneous changes in inflow wind conditions.
16 . The method of claim 14 further comprising:
mitigating adverse loads on the wind turbine due to instantaneous yaw misalignments caused by changes in inflow wind conditions, the inflow wind conditions comprising at least one of:
wind direction;
speed; and
atmospheric stratification.
17 . An apparatus for wind turbine optimization comprising:
a wind turbine;
a processor; and
a computer-usable medium embodying computer code, said computer-usable medium being coupled to said processor, said computer code comprising non-transitory instruction media executable by said processor configured for:
calibrating a controller with data obtained from experiments on models in wind tunnels the data comprising directly measured wake trajectory deviations collected by measuring velocity time-series signal spectral energy amplitude changes at periods equivalent to one or more rotations;
setting a desired location range of a wind wake with the controller;
determining an error signal;
adjusting a speed of a rotor associated with the wind turbine according to the error signal in order to minimize the error signal; and
confining a real-time position of the wind wake to the desired location range of the wind wake by minimizing the error signal.