Research And Application On Optimization Of Distribution Network Planning Based On Grid

Power distribution network planning is one of the important part in power grid planning and construction,and is the key to realize safe,reliable,high quality and economical power supply.The traditional power distribution network planning is based on the master network planning and is carried out in a "top-down" way.The drawbacks of the power distribution network planning constrained by the master network planning are constantly emerging,such as cross-supply areas,low inter-station contact rate,overlapping power supply ranges of power supply lines,indirect line routing and the long power supply radius.Therefore,how to scientifically and effectively carry out distribution network planning is an urgent research topic.This thesis puts forward an optimization method of power distribution network planning based on the idea of grid.The key of this planning method is the grid division of power distribution network.Based on the principle of grid division and the idea of grid layering,a new idea of grid division of power distribution network is proposed.Firstly,this thesis uses the improved K-means clustering algorithm based on density to divide the power supply grids in the planning area,and the load weight is used to make the load between the power supply grids keep relatively balanced;secondly,in order to ensure the reasonable power supply of power supply grids,this thesis uses particle swarm optimization algorithm to determine the location of power supply grids based on the results of regional load forecasting and power supply grid partition;thirdly,this thesis uses minimum weight matching algorithm to match several adjacent power supply grids to form a supply grid.The grid has independence and self-healing ability.At the same time,three kinds of connection modes of each power supply are determined,that is,matching between different power supply grids,matching between the same power supply grids and no matching between independent power supply grids.On the basis of power grid partition,this thesis establishes the path planning model of main supply line and tie-line in power distribution network,considers the factors of line channel and load center of power supply grid,uses the Dijkstra algorithm to solve the model,and takes a regional power grid as an example to analyze.The results show that the hierarchy of power distribution network structure planned by gridding method is clear.Meanwhile,the method effectively reduces the length of power supply lines and the investment costs of power distribution network planning and construction.The validity and practicability of the gridding method proposed in this thesis are illustrated,which can provide some theoretical reference for planners to carry out actual power distribution network planning.