Study On Distribution Network Planning Of Electric Vehicle Replacement Power Station Based On Partition

"With the rapid development of economy, the problems of the shortage of energy and pollution are getting more and more seriously. Due to advantages of the lower energy consuming and little pollution, the electric vehicle(EV) has already became the tendency of the automobile industry. There will be a huge effect on the grid as the large-scale application of EV. Reasonable layout of the charging stations could help on promoting the EV, also the storing energy property of the EVs’ batteries make the charging station plays a beneficial role in distribution network. Therefore, it is necessary to do research on the layout of the EV charging stations and the planning distribution network which contains charging stations.This paper studies the layout of the EV charging stations, division of service scope and the optimal switch configuration scheme of considering the charging station as the backup power supply based on the idea of partition. As shown follows are the main work:This paper states a distribution network partitioning method on the basis of self-adapting weighted Voronoi graph, according to the uneven distribution of the load. The substation load capacity, power distance, geographical barriers, grid attribution and other factors were considered in this method. In this paper, the expanding speed of the generating element in different directions is dynamically adjusted. Also, a concept of virtual element to solve the problem about the status quo of no power point in the partition is proposed. As the practical example shows, this method is effective and reasonable.In order to calculate the charging demands of EVs, this paper fully considers the tidal distribution of EVs in different partitions and the behaviors of different types of EVs. And the EVs charging load demand model on the basis of Monte Carlo simulation method is established. The example calculates the charging demand of EVs in each partition and the total charging demand of EVs in the area.This paper plans the EV charging station combined with the improved adaptive weighted Voronoi graph and center of gravity method based on the result of partition. The partition of EV charging station service scope is realized by using the improved adaptive weighted Voronoi graph, and the automatic searching in service scope of charging station is realized by using center of gravity method. An example indicates the method is effective and reasonable.This paper proposes the plan of taking the EV charging station in the partition as the stand-by power of the important load. The optimal switch configuration model is established with the object that the cost is minimum, through synthetically considering the reliability requirements of partition power supply, investment & maintenance cost and the system power failure cost. Finally, through the results of the example, it proves that it can reduce the loss of power failure of distribution network and improve the reliability of power supply.