Research On Wind Farm Distributed Active Power Allocation Strategy Considering Fatigue Optimization

With the continuous development of wind power industry,effective power control to improve grid friendliness has gradually become a consensus in the industry.Wind farms usually have a relatively simple flow direction.Under the current proportional power distribution method commonly used in engineering,the wind turbine located in the upwind has higher output,so the fatigue damage is often heavier,leading to the inconsistency of fatigue degree among wind farm units.The fatigue degree of wind turbine is different,and the maintenance cycle is not uniform,which increases the operation and maintenance cost of wind farm,and also increases the wear of wind turbine itself.Therefore,this paper mainly focuses on the research on the active power dispatching strategy of wind farm,aiming to balance the fatigue distribution of wind farm and reduce maintenance costs.The main research contents are as follows:(1)In order to allocate active power commands more accurately,the real-time effective wind speed of wind turbines is needed because the measured wind speed in wind turbine nacelle is easily disturbed and fluctuates greatly.In this paper,the effective wind speed prediction in front of wind turbine is divided into two steps:effective wind speed estimation and effective wind speed prediction.First,based on the support vector regression(SVR)algorithm,this paper establishes a wind speed SVR regression model,and fits the real-time measured wind speed of the nacelle with the lidar wind speed to obtain the effective wind speed.Then use the nonlinear autoregressive(NAR)model to predict the effective wind speed obtained in the previous step.The simulation experiment results show that the prediction results have high accuracy.(2)An optimized active power distribution strategy considering the fatigue degree of wind turbine was proposed.The strategy balances the fatigue distribution of wind farm by dispatching the active power of wind turbines.Wind farms are generally located in remote regions with large footprint,and at the same time,the number of wind turbines is increasing.Moreover,the centralized dispatching control has a large number of loads and a large amount of calculation.Thus,intelligent distributed dispatching will become a practical solution.This paper proposes an improved multi-agent consensus algorithm based on a distributed scheduling strategy.Through the information interaction between wind turbines,the active power commands are independently coordinated and distributed,which greatly reduces the amount of calculation in the wind farm control center.The simulation experiment results show that the optimized dispatching strategy proposed in this paper can significantly reduce the fatigue coefficient deviation between wind turbines on the basis of accurately tracking the power command of the grid,and the fatigue distribution gradually tends to be uniform,which can effectively reduce the maintenance frequency of the generators and reduce maintenance cost.