Numerical study and analytical modeling of yaw error effects on wind farm power performance

Given the inevitability of yaw error in wind turbine operation, this study effectively integrates computational fluid dynamics (CFD) simulations with analytical models to investigate its impact on wind farm performance. The CFD results demonstrate the necessity of accounting for yaw error effects in wind engineering practice, as it can significantly alter wake interference and thereby affect wind farm power output. In a neutral boundary layer, a 15° yaw error angle can lead to a change in wind farm efficiency exceeding 20%. To address the need for rapid and accurate power prediction for wind farms affected by yaw error in engineering practice, a novel analytical model is proposed, which incorporates the transverse velocity effects critical to wake interference among yawed turbines. Comparisons with CFD data from simulations involving 35 National Renewable Energy Laboratory 5 MW wind turbines under various yaw angle configurations reveal that the mean absolute percentage error (MAPE) calculated using the new model remains consistently below 5%, substantially lower than the conventional model's MAPE of up to 20.82%. Parametric studies based on the newly proposed model further indicate that the impact of yaw error on wind farm efficiency is highly sensitive to changes in turbine orientation and can be mitigated by increasing incoming turbulence intensity or expanding the wind farm size.