Study On Active Distribution Network Planning Based On Bi-level Planning Theory

With the shortage of traditional energy sources and the enhancement of people's consciousness of environmental protection,distributed generation(DG)has attracted worldwide application due to its flexible power generation and environmental friendliness.In order to adapt to an increasing number of intermittent distributed generations accessing systems,the traditional distribution network is actively developing into the active distribution network with active management ability.Active distribution network planning needs to consider the active management measures,the uncertainty of DG and load,and combine the planning with the operation and control on the basis of the traditional distribution network planning.In order to make the active distribution network planning more comprehensive,active distribution network planning needs to be studied.Firstly,this paper considers the uncertainty of intermittent DG and load.Secondly,this paper studies the planning of intermittent DG with the objective of regional energy supplier profit based on bi-level planning theory.Then,this paper studies the active distribution network reactive power compensation planning method considering the active management measures.Finally,on this basis,an integrated optimization method for intermittent DG and reactive power compensation of active distribution network is proposed.The main work of this paper is as follows:(1)Considering the uncertainty of intermittent DG and load,the K-means clustering algorithm is used to reduce the scene data of the wind speed,light intensity and load of 8760 hours to improve the computational efficiency of model solution and the reduction accuracy.(2)The regional energy supplier is the main body of DG investment under the electric power market environment,and the model of intermittent DG optimization is proposed which considers the uncertainties of DG output and load,as well as three active management measures including regulating reactive power compensation capacity,curtailing the output power of DG,and regulating the on-load tap changer.A hybrid strategy combining harmony search strategy and particle swarm optimization is proposed to solve the model.A simulation example is given to validate that the proposed model and the solution method can effectively increase the accessing capacity of intermittent DG and increase the comprehensive income of regional energy suppliers.(3)This paper studies the active distribution network reactive power compensation planning method considering the intermittent DG based on the active management measures,and proposes reactive compensation optimal allocation model in active distribution network.The bi-level programming model is solved by the harmony search algorithm and particle swarm optimization algorithm.The theory and example verify the planning model and solving algorithm can effectively reduce the comprehensive cost and network loss,and improve the overall voltage level of the system.(4)From the perspective of comprehensive planning for active power-reactive power,and considering the interests of regional energy suppliers and distribution companies,this paper takes economic index,voltage improvement index and reduction of system power loss as sub-objective functions,and Analytic Hierarchy Process(AHP)is used to allocate the weight of each sub-objective function.This paper proposes a comprehensive planning model of intermittent DG and reactive power compensation capacitor in active distribution network,and the harmony search algorithm and particle swarm optimization are used to solve the model.A concrete example is given to validate the proposed comprehensive planning method can reduce the network loss,improve the system voltage improvement index,optimize the operation mode of the system,and increase the income of the regional energy supplier.In this paper,active distribution network planning based on bi-level programming theory is studied,which can improve the penetration rate of DG and play the advantage of active distribution network actively,and has certain theoretical value and the project application value.