Three-dimensional wake flow wind speed distribution calculation method suitable for various terrains

Abstract

The invention relates to a three-dimensional wake flow wind speed distribution calculation method suitable for various terrains. According to the method, the influence of the coupling effect of the terrain acceleration effect and the wind shear effect on the fan inflow wind speed and the influence of the leeward slope terrain change on the wake flow center settlement height are considered; the wind speed and turbulent flow data measured by the foundation laser radar are combined to correct an inlet wind profile model, a turbulent flow intensity model and a wake flow sinking theoretical model, the precision of the models is ensured, and finally the wake flow wind speed distribution calculation method suitable for various terrains is established. And a precision guarantee is provided for power prediction, layout optimization and micro-siting of the wind power plant in the complex terrain.

Description

technical field [0001] The invention relates to the technical field of wind power generation, in particular to a three-dimensional wake wind speed distribution calculation method applicable to various terrains. Background technique [0002] The wake effect of the wind turbine is an important factor affecting the flow of the internal flow field of the wind farm. The reason for this is that the upstream wind turbine absorbs energy from the wind. According to the principle of energy conservation, the energy obtained by the downstream wind turbine decreases. Under the influence of the wake effect, the power generation of the downwind wind turbine decreases, and the load of the wind turbine increases exponentially with the increase of the turbulence intensity inside the wake. With the completion of the development of wind farms with flat landforms, areas with complex terrain rich in wind energy resources are gradually becoming the target of wind farm site selection. Wind farms w...

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Problems solved by technology

Wind farms with complex terrain are affected by factors such as wind shear effect (the phenomenon that the inflow wind speed in front of the wind turbine changes with altitude) and terrain fluctuations, which make the internal wake field of the wind farm complex, which seriously affects the power prediction and microscopic selection of wind farms. address precision

[0003] The existing advanced wake wind speed calculation method is mainly a three-dimensional wake model, which assumes that the inflow wind speed is a constant value, the wake expands linearly, and the wind speed distribution in the wake area is a Gaussian distribution. According to the mass / energy conservation law, the wake flow is established Regional wind speed distribution model, this type of method can accurately predict the wake distribution characteristics of flat terrain or offshore wind farms, but for complex terrain wind farms, there are uneven distribution of inflow wind profiles affected by terrain, wake sinking on leeward slopes, and wake The expansion is greatly affected by the distribution of turbulence intensity and other phenomena, all of which have a great impact on the wake wind speed distribution curve

None of the existing technologies apply the distribution characteristics of inflow wind speed under the coupling influence of wind shear and terrain acceleration effect, and the influence of terrain on wake sinking to the calculation of wake distribution method, and the correction model of turbulence intensity in the wake area adopts empirical values. The accuracy of the existing wake wind speed calculation method in predicting the wake distribution of complex terrain wind farms is questionable due to the lack of data source acquisition and correction combined with advanced lidar

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