| With the large-scale development and utilization of wind energy,the construction of offshore wind farm has become a hot spot in the development,utilization and research of global wind energy.As the wake effect makes the incoming wind speed pass through the upstream unit,the wind speed decreases,the turbulence intensity increases,and the output power of the downstream unit decreases.In order to reduce wake effects,simply increasing the spacing between units will lead to reduced land utilization,increased submarine cable costs and increased cable losses.This paper focuses on wind farm layout optimization,which considers reducing wake impact and reducing comprehensive cost.The main research contents of this paper are as follows:First,based on Jensen’s wake model,single-unit and multi-unit wake models and 5×5 rule wind farm wake models are established.The influence of wake effect on wind turbine and wind farm wind speed is analyzed and studied.The results show that wind direction and unit spacing affect wake wind speed between units.The wind farm wake superposition model,wind farm output power model and wind turbine investment cost model based on coordinate transformation are established,and the wind farm output power considering the wake effect is simulated.Based on the superimposed wake model and wind turbine cost model,the wind farm comprehensive cost model was established.The grid method was used to optimize the layout machine,and the information degree sc reening mechanism was introduced to remove the 3D grid spacing constraint.The results show that the adaptive genetic algorithm can effectively reduce the impact of wake.Aiming at the optimization problem of wind farm with row and row constraints,the boundary of wind farm was represented by linear function,and several feasible solution intervals were obtained according to row and row constraints.A dynamic coding genetic algorithm based on information degree screening mechanism was proposed.Simulation results show that this algorithm provides a feasible optimization scheme for wind farm layout in irregular areas.The constitution and cable selection of the collecting system of offshore wind farm are analyzed,the comprehensive cost model of the collecting system is established by adopting the tree topology structure,and the optimization strategy of dynamic Dijkstra algorithm is proposed.The fuzzy C-means clustering algorithm based on Angle classification is adopted to solve the constraint of the number limit of line mounted fans.The Delaunay triangulation algorithm was used to ensure that the cables could not be crossed.Dijkstra algorithm was used for many times to gradually connect the units to form a topology structure.The simulation results verify that the proposed planning method of wind farm gathering system reduces the cost of sea cable by adjusting the proportion of sea cable of different specifications.Aiming at the interaction between the comprehensive cost of laying machine and cable and generating income caused by wake effect.A two-layer joint optimization strategy of wind farm laying machine and cable is proposed,which takes into account the installed capacity of wind farm,installation position of wind turbine and topology structure of power collection system.The outer layer of the scheme takes the KWH cost of wind farm and the investment cost of power collection system as optimization objectives.The optimization scheme was solved by Non-dominated Sorting Genetic Algorithms(NSGA-Ⅱ).The two inner models take the comprehensive cost of the submarine cable and the production cost of the wind farm as the optimization objective respectively,and adopt the optimization algorithm of the dynamic Dijkstra algorithm and the adaptive genetic algorithm to solve the problem respectively.The simulation results verify the applicability and effectiveness of the double-layer joint optimization strategy of wind farm laying machine and cable laying,and provide a feasible scheme for wind farm planning. |
