The Research On County Mid-Low Voltage Distribution Network Plan

In recent years,the load of our country is growing rapidly as well as the national economy,forced power cut is seen everywhere.Especially for some mid-small cities and most county towns, forced power cut is prominent in power utilization peak.Because of the lag of construction,out of date facilities,irrational network structure and low reliability existed in most of the distribution networks.The distribution network,especially the mid-voltage distribution network,can not meet the needs of load increase. Distribution network,as the connection between the generation and transmission system and consumers,has gained more and more attention on their design and planning in recent years,but for most county towns,the electric distribution network still needs to be strengthened.According to the characteristics of the electric distribution network of Jinxian county,this paper specifies the whole planning idea form,i.e. the analysis of current status,to the drawing out the new scheme of network planning applying new optimized methords.Especially the two important links,i.e. the load forecast and power balance calculation are emphasized.Firstly,the status of Jinxian electric distribution network is analyzed to find out the main problems of the network.Secondly,a variety of load forecasting algorithm is used to forecast the load increasing,and the new substation locating is planed combining with the results of load forecasting.Thirdly,the county mid-voltage distribution network is optimized according to the main requirements aiming at county distribution network proposed by National Grid.After discussion with experts and seasoned technicians,the planning principles for Jinxian county distribution network are established ,and the basis for future grid construction,modification and optimization is provided to ensure the distribution network has high power supply reliability and economic running modern electric network to satisfy the needs of city construction and economic development.Fourthly,the network planning investment has been estimated,and the economic benefits produced by it is analyzed.