| The energy crisis and environmental deterioration bring dual pressure to traditional auto industry, therefore, electric vehicle (EV) has become the main development direction in the future. But the shorter driving range, the amount of the existing charging stations is small and many other reasons make users generate anxiety about the charging, which impedes the use and promotion of EV. In order to recommend a suitable charging station for EV to charge, we need to research on the effective EV charging mentoring program. Reasonable charging scheme is important for users of EV to reduce travel cost, improve operating efficiency of the charging stations, promote the construction of charging stations and the development of EV industry, thereby, making a great significance on the improvement of traffic environment.Currently research on EV charging problems is mainly account in the path planning of single EV, usually not fully consider the time, the fee, the distance that charging need to cost. And the research on charging service for multiple electric vehicles is less. In addition, there is almost no charging research on the perspective of charging station operators. But the efficiency improvement of operators could stimulate building of the charging stations and offer better service for EV. The paper establishes charging optimization models for EVs respectively from two perspectives of the users and operators, so as to provide a reasonable and practical solution for EV charging.Firstly, analyze charging demands from the perspective of EV users, determining the factors affecting the choice of charging station:the total distance, the total time and the charge cost. And use the relevant theory to quantify these factors to get the quantitative expression. Among them, we focus on the queue time, according to the vehicles’number in charging station, real-time charging schedule of charging piles and so on, queue time prediction theory and method is presented and the calculation expression is induced. It lays the foundation to the establishment of user-oriented charging optimization model.Secondly, analyze charging demands from the perspective of charging station operators, determining the effects on the operators of where EV to charge. Operators benefit from the balance of three aspects, including operating income, service level and charging distribution. In this paper, use relevant theory to quantify the three factors. It lays the foundation to the establishment of operator-oriented charging optimization model.Again, the user-oriented model is established according to the result of user-oriented charging quantization, the operator-oriented model is established according to the result of operator-oriented charging quantization. Use fuzzy programming method and genetic algorithm to solve the two models. Based on this, a comprehensive model of two angles of users and operators is constructed and solved.Finally, for the user-oriented model, operator-oriented model and the comprehensive model, the paper respectively make simulation verification and case verification. In the simulation verification, the realization process of the model is deduced in detail by setting the charging demand scene of three EVs and four charging stations. Results show that the models established in the paper could get correct and reasonable schemes for EVs. Case verification takes advantage of the three models to provide charging service according to the actual charging station data of Beijing and the EV charging demand data of large number. And draw the conclution that the user-oriented and operator-oriented model can provide optimal charging scheme from different angles. Compare the result of comprehensive model with the result of the shortest route model, it proves that comprehensive model could significantly reduce the charging cost of the users and improve the operational efficiency of the charging stations. |
PDF Full Text Request