Research On Local Wind Direction Fluctuation Behavior And Yaw System Optimization Of Wind Turbine

As traditional energy sources are increasingly exhausted,wind power,as a clean energy source,has been widely developed.Moreover,the increase in the capacity of a single wind turbine and the continuous improvement of advanced power generation technology have made the cost of wind power generation lower and lower,and the development prospect and economic benefits of wind power have become increasingly prominent.The randomness and volatility of the wind make it difficult to utilize wind energy.With the continuous change of wind direction,the yaw system needs rotate the cabin to the wind to obtain more wind energy and increase power generation.But when the wind fluctuates frequently and violently,the yaw actuator will work frequently,and this will result in serious mechanical wear on the yaw bearing et al.In the event of a failure,for the benefit of wind farms,the loss is huge.At present,there is no index to measure the wind direction fluctuation of wind farm,and the existing yaw system restart risk control strategy only pursues the maximum utilization rate and generation capacity of wind energy in theory,without considering the optimal economic benefits of the life cycle of wind turbine system componentsAiming at the above problems,this paper takes 2MW wind turbine as the research object.Firstly,the local wind direction fluctuation quantity of wind turbine is defined and the statistical method of wind direction fluctuation is introduced.A set of indexes to measure the fluctuation characteristics of wind direction are proposed.The method of subregional description of the fluctuation characteristics of wind direction can be used to describe the fluctuation of wind direction macroscopically.On this basis,by fitting the edge distribution probability density function of wind direction fluctuation quantity and using the copula function to connect,the joint distribution function of wind direction fluctuation quantity is obtained.A set of probability distribution indexes which can accurately quantify the local wind direction fluctuation characteristics of wind turbine is extracted,and a more detailed probability description of wind direction fluctuation is carried out,which plays an important role in guiding the individualized parameter optimization settings of yaw system of wind turbine and improving the generation efficiency of wind turbine.Based on the rule of rain flow count method and the Miner guidelines,the yaw bearing fatigue life loss is quantitatively analyzed,and yaw system restart control model is established.Taking the comprehensive economic benefits of wind farms as the optimization objective,the pso-ga hybrid optimization algorithm is adopted to optimize the balance between the power generation efficiency and the service life of the wind turbine equipment,so as to achieve the goal of optimal overall comprehensive economic benefits of wind farms.The research results show that the wind direction fluctuation characteristics described in this paper can accurately describe the local wind direction fluctuation characteristics of wind turbine sets.For wind turbine sets with stable wind direction,the yaw parameter setting value should be appropriately reduced to increase its sensitivity to stable changing wind direction,and more wind energy should be captured at the cost of fewer yaw times.For wind turbines with poor wind direction stability,the yaw parameter values should be increased appropriately to reduce the sensitivity to the frequent wind direction fluctuation.Under the premise of little reduction of power generation,the yaw times is greatly reduced,which will cut down the self-power consumption and yaw fatigue load of the wind turbine.Finally,the target of matching the control parameters of the yaw system with the local wind resources of the wind turbine is reached.