| Distributed energy system has the characteristics of reasonable utilization of energy,economy,flexible operation,environmental protection and energy conservation,and has significant development potential and broad prospects.In the planning of regional distributed energy system(RDES)under the background of energy Internet,energy production and energy utilization are closely linked and cannot be separated from the energy stations and energy supply networks.Their design and planning determine whether the system is reasonable or not.On the premise of ensuring reasonable,how to save cost and improve system performance,through optimizing configuration,optimizing station and networks layout and improving system comprehensive energy efficiency is the key to RDES planning.From the perspective of graph theory,this paper constructs a P-median model for site selection and proposes a method of station-network cooperative optimization,which provides some new ideas for the optimization layout of RDES station and networks.Firstly,the P-median station and networks layout model based on cost is established.The economics of station and networks layout are considered from four aspects:initial investment of networks,energy loss of networks,operation cost,depreciation and maintenance cost.Through the establishment of a mathematical model,the station-network cooperative optimization algorithm is used to realize the optimization of two different value scales,which unifies the optimization of regional energy station and pipeline networks layout.The minimum spanning tree corresponding to the minimum cost parameter is found through the cost models of the cooling networks,the heat networks,the electric networks and the energy station,so as to determine the most cost-effective optimal layout.Secondly,taking the energy system in the western district of a high-tech industrial development zone as an example,the calculation example is analyzed.According to the load situation in the western region,the shortest distance matrix and the shortest path matrix are obtained,thus determining the energy station sites and the pipeline networks layout.Compared with other schemes,the scheme determined by the algorithm in this paper is more economical,and the minimum annual cost is2.009×10~8 yuan.Finally,the layout planning of regional networks is compared and evaluated.This paper analyzes and compares the scheme and the comparison scheme from five aspects of networks connectivity,pipeline efficiency,networks density,networks adaptability and networks uniformity.The results show that the optimization algorithm in this paper is not only economical,but also has better networks characteristics.The station-network cooperative optimization method provides a new basis for the optimization of the networks layout of the distributed energy system,and also improves the integrity of RDES planning. |
