New Models And Differential Evolution Algorithms For Wind Farm Optimization

Wind power has been paid more and more attention in the world as an effective clean energy.In the design of wind farm,the reasonableness of facilities’ location,installation and layout of line directly affects the power output and profit of wind farm.Optimization of wind farm includes wind farm layout optimization problems and electrical system optimization problems.Among them,the wind farm layout optimization problem includes micro-sitting optimization problems and macro-sitting optimization problems.The optimization of electrical system mainly involves cable layout optimization and the optimal location problem of the offshore substation.The wind turbine is one of most important equipments in a wind farm,and its layout is the main research issue in the micro-sitting optimization problem.All the time,wind farm layout optimization and route optimization are difficult problems in engineering field due to the influence of wake effect and layout of equipment.Based on bilevel programming model,this thesis focuses on the micro-sitting optimization problem of onshore wind farm and joint optimization of both micro-sitting and electrical system of offshore wind farm,the main research results are as follows:In order to effectively deal with the micro-sitting optimization problem of onshore wind farm.Firstly,a new bilevel programming model is proposed in this thesis.In the proposed model,the upper-level problem aims to maximize the overall profit of the wind farm,while the lower-level problem aims to maximize the power output of the wind farm.Secondly,for lower-level problem,an improved differential evolution algorithm is developed by embedding better individual information into the mutation operator.Finally,when the wind farm area is fixed,the optimal layout of wind farm is given with the maximal profit under two wind conditions.At the same time,the proposed algorithm is compared with four other popular algorithms under the same wind conditions.The results show that the proposed algorithm is effective for solving this kind of problem.Different from onshore wind farm,there are much more expensive cables to connect wind turbine in the offshore wind farm.Therefore,it is very important to optimize cable connection layout for offshore wind farm.Firstly,for the joint optimization of both micro-sitting and electrical system of offshore wind farm,a new hierarchical optimization model is proposed,and further simplified into a bilevel programming model according to the characteristics of the problem.In this model,the upper-level problem is mainly to optimize the layout of wind turbine,the lower-level problem is mainly to optimize the layout of cable.Secondly,a new method for determining the location of offshore substation is presented.Finally,the Prim algorithm is modified according to the location requirements of submarine cable layout.When the wind turbine’s layout and the position of offshore substation are relatively determined,the algorithm can effectively obtain the optimal connection scheme of submarine cable.The effectiveness of the proposed technique is verified by simulation experiments under two common wind conditions.