Optimization Of Capacity Allocation Of Expressway Independent Microgrid With Charging Pile Siting And Capacity Setting

With the growth of energy demand in traffic energy scenarios represented by expressways,traffic energy systems need to make full use of their natural resource endowments to form an independent microgrid system with independent energy supply in weak grid areas where traffic is accessible,thereby ensuring the normal operation of traffic energy systems.This thesis takes the expressway microgrid as the research object,and studies the problems related to the location and capacity of the expressway charging pile and the capacity configuration of the expressway independent microgrid.In view of the increasing demand for electric vehicle charging in weak power grid areas on expressways,this thesis proposes a strategy for site selection and capacity determination of expressway charging piles.Firstly,combined with the highway mileage information and the electric vehicle mileage information,the heuristic algorithm is used to determine the initial candidate site of the charging station in the road network.Secondly,on the basis of fully considering the traffic flow information of expressway sections and the initial state of charge of electric vehicles,a dynamic programming method for the optimal location of expressway charging stations is proposed with the goal of minimizing the comprehensive cost of charging stations composed of construction cost and operation cost.The model is solved by taking the expressway network designed in this thesis as an example to verify the effectiveness of the method.Based on this,the Monte Carlo method is used to establish the probabilistic charging model of electric vehicles in the service area,which provides data support for the subsequent optimal configuration of the capacity of the expressway independent microgrid.Aiming at the problem of energy supply shortage in weak grid areas on expressways at this stage,this thesis proposes a bi-level programming model of expressway independent microgrid,which can effectively ensure the stability of dynamic operation of microgrid system while realizing capacity planning.By analyzing the sequential operation process of the independent microgrid system of the expressway,a bi-level optimization model of microgrid capacity configuration and operation is constructed with the minimum annual cost of the whole life cycle of the microgrid system as the goal in the upper level,and the minimum daily operation cost and environmental governance cost as the goal in the lower level.The dual carbon target,the local consumption rate of renewable energy,and the power shortage rate of abandoning wind and light are taken as constraints.Taking an expressway service area in Xinjiang as the research object,the combined output of power generation units in the windsolar-diesel-storage microgrid of the expressway and the sequential access state of electric vehicles are considered.A capacity configuration planning method for power generation units in independent microgrid during expressway planning period is proposed,and the effectiveness of the method is verified.The research results of this thesis theoretically enrich the planning theory and method system of charging stations and independent microgrids on expressways,and broaden the application scope of Monte Carlo simulation,mixed integer programming model and heuristic algorithm.It provides a useful reference for the optimal configuration of independent microgrid capacity in expressway network,and has certain theoretical research and practical guiding significance.