Atmospheric conditions and yaw misalignment significantly impact wind turbine power production

The yaw drive in a wind turbine is typically used to keep the rotor facing into the wind. Intentional misalignment of the yaw for upwind turbines in a wind farm has proven to be useful for maximizing collective wind farm power generation. The potential to increase collective wind farm power depends on the relationship between yaw misalignment and the power of the yawed turbine.

Howland et al. proposed a model for power production of a wind turbine in yaw misalignment that includes effects of changes in wind speed and direction over the wind turbine face. They also performed field experiments to validate their model.

Previous studies have found a wide spread in the relationship between yaw misalignment and turbine power. The group developed a general physics-based model for wind turbine power based on wind conditions and yaw misalignment that can be readily applied at any wind farm.

The model was validated by comparison to field data from a wind farm in Northwest India that contained almost 100 turbines. Velocity profiles as a function of height were measured using a pulsed lidar system.

“Our model is able to capture the qualitative trends observed in the complex field data and reduced the quantitative prediction error compared to the standard model used,” said author Michael Howland.

Wind turbines are increasingly placed in new locations such as mountainous terrain or offshore, floating environments. These more complex conditions have critical impacts on wind turbine performance.

“As wind turbines continue to increase in rotor diameter and hub height, wind condition variations over the wind turbine face become more significant and improved models are needed for reliable energy estimates,” Howland said.

Source: “Influence of atmospheric conditions on the power production of utility-scale wind turbines in yaw misalignment,” by Michael F. Howland, Carlos Moral González, Juan José Pena Martinez, Jesús Bas Quesada, Felipe Palou Larrañaga, Neeraj K. Yadav, Jasvipul S. Chawla, and John O. Dabiri, Journal of Renewable and Sustainable Energy (2020) The article can be accessed at https://doi.org/10.1063/5.0023746 .

This paper is part of the Advances in Wind Plant Controls: Strategies, Implementation, and Validation Collection, learn more here .