Research On Wind Farm Power Optimitization Method Based On Active Wake Control

With the large-scale development and utilization of offshore wind power,the arrangement density and unit capacity of offshore wind farms continue to increase,which makes the wind speed attenuation more obviously after the incoming wind speed passes through the upstream wind turbines,decreasing the output power of the downstream generators and increasing the fatigue load of the unit,thereby increasing the operation and maintenance cost.In order to reduce the wake effect of offshore wind farms,this topic focuses on wind farm power optimization methods based on active wake control,and mainly completed the following research work:(1)Aiming at the problem of wind farm wake calculation,the FLORIS wake model is used to carry out research,and simulate and summarise of the overlap of wake and wind wheel,the calculation method is proposed for the special overlap caused by the FLORIS wake model.For the problem of wake velocity caused by the limitation of the wake model,the equivalent model of energy conservation is proposed.to improve the calculation method.(2)Aiming at the problem of non-yaw crew load calculation,the leaf element momentum theory is used to establish a load model.Aiming at the load calculation problem of the yaw unit,adopt the leaf element momentum theory and the wind speed decomposition method,and the influence of the wind speed on the leaf element tangential velocity,the composite velocity and the angle of attack is discussed and analyzed by decomposing the incoming.flow wind vector of the yaw state.The calculation method was improved,the load calculation model under the yaw situation was established and the validity was verified.(3)Aiming at the significant problem of the wake effect of offshore wind farms,the active wake control strategy is adopted to study the relationship between the size and direction of the wake and the output power of the unit.The research shows that this strategy can effectively weaken the wake,which is validated by simulation.(4)On the basis of research(3),an active wake optimization control method is proposed,and the particle swarm algorithm is used to optimize the axial induction coefficient and yaw angle of the unit to adjust the size and direction of the wake.Through simulation verification,it is proved that the method can effectively weaken the wake effect,increase the output power of the wind farm,and reduce the load of the wind farm.