Optimal Control Of Active Power Output Of Wind Farm Considering Wake Effect And Load Loss

In recent years,with the rapid development of the wind power industry,the capacity and arrangement density of wind turbines in wind farms have continued to increase,and the impact of wake effects between wind turbines is becoming more and more difficult to ignore.The wake effect will not only cause the loss of wind speed in the downstream of wind turbine,but also increase the intensity of wind turbulence,which will reduce the output power of the downstream wind turbine of the wind farm and increase the load loss.However,the traditional maximum power point tracking strategy does not consider the impact of aerodynamic coupling between wind turbines,it is difficult to solve the problems caused by the wake effect.Therefore,analyzing the relationship between the wind turbine operating state parameters and the wake distribution,power output and load loss,adopting the method of control wind turbine operating state to reduce the impact of the wake,increasing the wind farms power output and reducing the load of the wind turbine has become one of a solution to the current situation.Focusing on this topic,the main research contents of the thesis are as follows:Based on the momentum theory of wind turbines,explained the energy conversion process of wind turbines,and the relationship between the axial induction factor and thrust coefficient of wind turbines,wind energy utilization coefficient and active power output is studied.Then established the Jensen wake model,the wind farm wake superimposed wind speed calculation model,and the wind farm wake wind speed calculation model when the wind direction changes.In order to reduce the impact of wake effects on the power output and load of wind turbines in wind farm,based on the relationship between the wake wind speed distribution of the wind turbines in the wind farm and the operating state parameters,power output,and load loss,the relationship between the distribution of wind farm wake wind speed and the operating state parameters,power output,and load loss of wind turbines.The maximum of whole power output of the wind farm And the minimum load loss as the objective function,proposed a wind farm power output optimization control model considering wake effect and load loss.For wind farm optimization control models that consider wake effects and load losses are high-dimensional,nonlinear,and multi-parameter couplings and traditional optimization algorithms are difficult to meet the control requirements.The thesis introduces a Whale Optimization Algorithm that is suitable for solving large-scale and complex problems.For the problem of slow convergence in the later iteration of the algorithm and local aggregation of optimal individuals,a nonlinear convergence factor and nonlinear weight formula are proposed to coordinate the global and local search capabilities of the algorithm,and then the hybrid frog leaping algorithm is introduced to change the worst frog position.The strategy improves the ability of the algorithm to jump out of the local optimum,and finally verifies the accuracy of the proposed Improved Whale Optimization Algorithm(IWOA)through the test function.Finally,introduced the basic idea and framework of wind farm optimization control method considering wake effect and load loss.Aiming at the proposed optimization control model,use MATLAB software to take the Horns Rev1 wind farm in Denmark as a case,the axial induction factor is the control variable,and the IWOA algorithm is the optimization algorithm for simulation analysis.It is verified that the proposed optimization control method can effectively increase the output power of the wind farm and reduce load loss of wind turbines.