A Yaw Optimization Control Strategy For Wind Turbines With Adaptive Wind Conditions

The yaw system is an important component of the WTGS(Wind Turbine Generator System)control system.Yaw control strategy directly determines the efficiency of the wind power utilization of the WTGS,meanwhile it affects the failure rate and the service life of the WTGS.For the current WTGS,the fixed yaw error angle,fixed wind direction and fixed yaw angle duration control strategy are commonly used,it leads to the phenomena of the "over-yaw" and "under-yaw".Based on the above engineering practical problems,this paper proposes a yaw optimization control strategy for wind turbines with adaptive wind conditions.Adaptive wind conditions,that is,the wind turbine group automatically adapts the control parameters to the different wind conditions by analyzing and calculating the historical wind data.The specific research contents are as follows:First,detailed introduction to the basic components of the wind turbine and the function and working principle of the yaw control system,and then,according to the aerodynamic theory of wind turbines,the wind speed characteristics and yaw error are analyzed to provide a theoretical basis for the optimization of yaw control strategy.And we can point out the necessity of adaptive wind yaw controlSecondly,screening wind turbine Supervisory Control And Data Acquisition(SCADA)historical data,then depicting wind power scatter plot,and applying Fourier series fitting to obtain the wind power curve of the unit under normal operating conditions.According to the effects of running characteristics of the wind turbine due to yaw error at different wind speeds and different running stages are different,and take into account the probability distribution of wind direction and its relation with wind speed,new yaw control method of subsection optimization strategy was proposed,dividing the working condition based on the operating state of the fan.In this paper,the power generation and the yaw process power consumption are taken as the objective function.By calculating the historical data of the unit under various working conditions,the wind characteristics such as wind direction change frequency and wind direction duration are calculated.Then we will analyze the corresponding wind direction change angle Aa when obtaining the maximum power generation and the most representative yaw delay time At is the condition for starting yaw after optimization.So we can establish an optimized yaw control strategy model.Finally,based on the optimized yaw control strategy model,it is determined that the yaw operation needs to be initiated to study the yaw operation angle of the wind.Firstly,the K-means algorithm is used to cluster the historical data to obtain cluster centroid points of different categories.And use the centroid point calculation method to classify the current real-time wind direction changes.Then BP neural network trained under different categories is called to predict the future wind direction,and applied to the optimized yaw control strategy as the yaw operation angle.The verification shows that the yaw optimization control strategy model improves the yaw wind accuracy and significantly increases the power generation.At the same time,it also reduces the yaw frequency and failure rate of the unit and prolongs the service life of the unit.