The Mobile Charging Vehicle Routing Problem

Due to the environmentally friendly nature of Battery Electric Vehicles(BEVs)with no exhaust emission and low noise,it is receiving more attention.Governments have implemented welfare policies,such as free parking,for BEVs to promote the popularization and promotion of BEVs.Because BEVs have shorter running distances than Fuel Vehicles(FVs),drivers have greater range anxiety.In the short term,it is unrealistic to improve BEV's battery technology so that its operating range is close to FVs.At present,there are three types of charging methods,such as plug-in chargers,charging lanes,and battery swapping stations,which can only replenish electricity for BEVs in fixed positions,which cannot solve the charging problem of BEVs better.However,based on charging requests sent by BEV drivers,Mobile Charging Vehicles(MCVs)arrive at requested locations and provide charging services within service time windows.During charging services,BEV's drivers can leave their cars.Therefore,MCVs can better solve the charging problem of BEVs.Currently,mobile charging services are operated by Eyuechongdian and Nio Power.However,there are certain differences in the MCVs operated by these two companies.Fuel MCVs(FMCVs)are used by the Eyuechongdian company.The batteries carried by FMCVs are only used to replenish the BEVs at customer nodes.When the battery charge is low,it will arrive at charging stations for replenishment.Nio Power uses Electric MCVs(EMCVs).The batteries carried by EMCVs are not only used for their own operation between nodes,but also for charging BEVs at customer nodes.When the battery charge is low,it will also reach charging stations to charge batteries.However,these two types of MCVs only charge BEVs through electricity transfer,which is simple.Therefore,based on difference between the electricity consumption mode and the charging method of these two types of MCVs,this paper first study the Vehicle Routing Problem(VRP)of these two types of MCVs.The mixed integer linear VRP models are respectively established.Moreover,based on the VRP research of EMCVs,this paper further studies the Location-Routing Problem(LRP)of EMCVs.This paper assumes there are three types of charging stations with different costs and different charging rates.At the strategic level,EMCV's operators need to determine the location,the number of charging stations,and the charging rate of charging devices under budget.Subsequently,at the tactical level,operators need to optimize the service routes of EMCVs.Finally,through the linearization process and the proof of model equivalence,this paper establishes a linear LRP model of multiple types of charging facilities with different charging rate for EMCVs.In this paper,for the three models,36 test instances are respectively generated based on famous Solomon instances,and numerical analysis is performed.In the basic numerical results,there are fewer arranged MCVs and shorter total traveled distances for instances with wider time windows.Subsequently,we conduct sensitivity analyses on factors such as battery capacity,charging rate,and service rate of MCVs that may affect the MCV's service routes.In sensitivity analysis results,large battery capacity,fast charging rate,high service efficiency can improve the service flexibility of MCVs,thereby reducing the total number of MCVs requested and the total running distances.Finally,we summarize the contribution and results of the article,and further briefly explain the possible research directions.