Electric Vehicle Routing Problem With Time Windows And Multi-type Vehicle Considering Partial Recharging Strategy

Electric vehicles(EV)with characteristics of low energy consumption and low pollution,Urban logistics distribution prefers electric logistics vehicles,which is of great significance to alleviating urban environmental pollution problems and improving social public benefits.At present,charging stations is insufficient,irrational location,and misgovern.It has become one of the main obstacles for the promotion and application of electric logistics vehicles.The problem of “difficult charging”of electric vehicles is still serious.In addition,logistics companies lack a scientific and rational planning method,leading to the performance of electric logistics in practical applications unsatisfactory.In order to improve logistics efficiency and reduce costs,electric vehicle routing problem has attracted scholars and enterprises Increasingly.Considering that most logistics companies have multiple types of electric logistics vehicles,it is material to study vehicle routing problem considering multiple type and partial charging strategies.Vehicle routing problem belongs to NP-hard problem.So the constraints of multi-type and partial charging are added,putting problem more complicated and more difficult solved.Therefore,it is of great theoretical and practical significance to conduct deeply research on electric vehicle routing problem with time windows and multi-type vehicle considering partial recharging strategy,and to design efficient algorithm to succor enterprises reduce operating costs and improve efficiency.This study first summarizes the classification elements and related algorithms of vehicle routing problem;then establishes a mathmatical model to electric vehicle routing problem with time windows and multi-type vehicle considering partial recharging strategy,which carrying cost and vehicles use cost are reduced;finally improved branch and price algorithm and an adaptive large neighborhood search algorithm with enhanced local search(ALNS-LS)are designed to solve this problem.In third chapter,impove branch and price algorithm and modify Solomon instances which are used as experimental data.The effectiveness and accuracy of the improved branch and price algorithm are analyzed and the sensitivity analysis of the variable cost of the vehicle is performed.The results show that the improved algorithm can solve Small-scale problems in a reasonable time and have certain use value.In fourth chapter,ALNS-LS heuristic algorithm is designed.Combining the problem characteristics,ALNS-LS designs the customer neighbor insertion algorithm to construct the initial solution and builds the local enhanced search algorithm by grouped multiple intra-path and inter-path operators to improve the algorithm’s optimization ability.The effectiveness and convergence of ALNS-LS are verified in modified Solomon instances.The simulation study of the instance is carried out to compare difference which is solved under partial recharging strategy and full charging strategy.The experiment shows that the ALNS-LS algorithm can obtain a better solution in a reasonable time and has practical application value.