Research On Dynamic Equivalence For Wind Farm Considering Correlation Of Wind Speed

When studying the impact of wind farms on grid stability,due to the complexity of the wind turbine model,if a detailed model of the wind farm is established,the amount of calculation will increase.Therefore,finding a suitable wind farm dynamic clustering method to simplify the model has become a research hotspot.In this paper,the wind farm system is taken as the research object,and the dynamic equivalence modeling method of wind farm considering wind speed correlation is studied.The main work is as follows:Firstly,based on the Correlation theory,the wind speed correlation is analyzed in depth,especially the correlation between the input wind speeds of wind turbines inside the wind farm under complex terrain.Modeling wind speed,including combined wind speed model and turbulent wind speed model,and analyze wind speed,including tail characteristic analysis and rank correlation coefficient.Next,the wind resource analysis software WAsP is used to model the steady state of large wind farms under complex terrain.The Weibull distribution and the wind direction rose diagram of the wind speed are fitted.According to the historical data,the shape parameters of the wind speed Weibull distribution are calculated.Scale parameters,etc.The wind power curve,speed curve,thrust curve and noise curve of the wind turbine were simulated,and the input wind speed was simulated under different heights,surface roughness and turbulence intensity.Then,the traditional wind farm equivalent method does not consider the topographical factors,which will cause the modeling accuracy to decrease.This paper considers the influence of terrain factors(including surface roughness,wake effect,irregular distribution of collector cables,etc.)on the unit.A dynamic grouping method for wind farms.For the irregularly arranged units in complex terrain,the characteristics of the doubly-fed unit are obtained according to the principle of coherence determination,and the wind farm is grouped based on the rotor current disturbance curve.Finally,according to the results of coherent dynamic grouping,the equivalent parameters of the wind farm are solved.For a large wind farm,due to changes in the topology of the in-situ collector network,there is a certain difference between the dynamic characteristics of each unit in a large wind farm.In this case,special consideration should be given to the impact of the collector network on the clustering of the in-field component groups,and then the appropriate wind farm equivalent method can be found.In this paper,the equivalent calculation method for the doubly-fed wind turbines in the same cluster is proposed,and the specific analysis is given with examples.The final simulation verifies the effectiveness of the dynamic equivalent method of wind farm considering wind speed correlation.