Research On Distribution Network Planning Adaptable To Intergration Of Diversified Electric Sources And Loads

With the continuous transformation of energy structure and upgrading of consumption,in recent years,the rapid development and large-scale application of clean energy such as wind energy and solar energy effectively guarantee the energy security and clean application of resources.However,due to the unstable output of the distributed generation,the passive absorption and acceptance of the power system will bring a lot of impacts on power flow,power quality,grid reliability,peak load regulation and frequency modulation.At the same time,the penetration of distributed generation continues to increase,the rapid development of diversified loads such as electric vehicles,and the continuous application of energy storage technology.The traditional distribution network can no longer meet the current needs,so it is urgent to transform to the active distribution network.In view of this reason,this paper studies the active distribution network which adapts to the distributed generation and diversified load access,studies the network structure and optimal access capacity of the active distribution network,so as to increase the absorption capacity of the active distribution network to the distributed energy,and improve the power supply reliability,power quality and investment rationality of the active distribution network.First,research on the impact of intergration of diversified electric sources\loads storage on the active distribution network.Analyze the output characteristics of photovoltaic power generation and wind power generation,and the influence of various distributed power sources on distribution network;study the active distribution network load classification method,and the impact of diversity load on the distribution network,and based on the electric vehicle load,an analytical model is established to study the influence of diversity load on the operation characteristics of the distribution network.The load/output characteristics of energy storage are analyzed,and the influence of energy storage and discharge on the distribution network is studied.The simulation method of hybrid output characteristics with distributed power supply and diversity load is proposed,and the distributed power supply to the distribution network is proposed.The model is influenced and verified by simulation calculation.Secondly,Active distribution network grid structure planning for multi-source and source access.Based on the research of the distributed power supply and the natural characteristics of the diversity load and its interaction with the distribution network,the planning objectives,planning principles and planning process for adapting the development of the active distribution network are proposed.The two considerations of economy and penetration are proposed.Layer network network planning method,through the joint optimization of upper and lower layers,to obtain the optimal grid solution and improve investment accuracy.Finally,the evaluation and analysis of the grid structure to adapt to the flexible operation of the active distribution network.This paper analyzes the current gridstructure of 10kV distribution network in China,puts forward a typical grid structure which adapts to the flexible operation of active distribution network,and gives the transformation scheme and planning strategy of active distribution network structure;analyzes the impact of the access of distributed power to active distribution network under different permeability,compares the applicability of lOkV line to distributed power in different typical connection modes,and The planning case of Qingdao Innovation Zone is illustrated in practice,which provides reference for the planning and design of grid structure transformation and investment decision-making of active distribution network.