分布式电动汽车充电桩信息安全防护技术研究与实现

论文对分布式电动汽车充电桩信息安全防护技术进行研究,分析充电桩信息安全防护技术应用,注重提高防护技术应用可行性与安全性。对分布式电动汽车充电桩通行特点进行分析,探究信息安全防护方案。     

城镇水价收费制度研究

基于调研数据,对影响城镇水价收费制度改革的诸多因素进行了order probit模型的计量分析。研究发现,居民水费支出、收入水平和住房面积等因素,对收费制度改革具有显著的影响关系,而环保宣传、地区因素和居民个体特征因素的影响关系不显著。在此基础上,提出了城镇水价收费制度改革的对策建议。     

锌银蓄电池智能充电机设计

介绍了一种基于单片机与专用集成PWM控制器SG3525的锌银蓄电池充电机。在分析锌银蓄电池特性基础上,采用模糊算法控制和单片机智能控制,对充电状态实时监控,并采用分段式充电方案,提高充电稳定性,克服了电压突变等带来的充电假结束或不饱和的缺点。通过在常规的BUCK充电电路中设计2只开关管轮流导通方式,使开关管工作在轮流导通状态,并通过实验进行验证,解决了驱动电路变压器驱动能力问题。     

含电动汽车的光/储/燃充电站最优容量配置及经济性分析

针对城市居民区充电难状况,建立一种包含光伏电池、燃料电池和储能蓄电池的电动汽车充电站容量配置模型。以成本最小化和负荷方差最小化为目标,采用NSGA-Ⅱ(二代非支配排序遗传算法)对模型进行求解。对于求得的可行解,首先使用净现值法对部分解进行经济性评估,然后采取峰谷负荷差率进行进一步评估,经过两轮筛选得出最优解。仿真算例验证了模型及评估方法的可行性。     

基于复杂网络理论的电动汽车充电设施布局合理性研究

提出了一种基于复杂网络理论构建电动汽车充电设施网络的模型,分别构建了上海、西安、合肥和大连的电动汽车充电设施网络,并分析了其电动汽车充电设施的运营情况以及布局的合理性。通过构建理想情况下的电动汽车充电设施网络,研究电动汽车充电设施网络的发展趋势。仿真结果显示:电动汽车充电设施网络的结构对电动汽车充电设施的利用率和稳定性有显著影响——该研究结果在实际网络中得到了验证。     

Network impacts of distance-based road user charging

Distance-based road user charging is being seen as one potential mechanism to implement national road charging schemes. This paper investigates the design aspects of universal distance-based charging schemes and incorporates procedures within a detailed network supply model to represent how a range of different permutations of distance-based charges across a given network (charging regimes) affect route-choice, travel characteristics and demand for road space. The results suggest that distance-based charging can reduce number and length of trips, congestion, accidents and pollution, and provide net economic benefits and revenues. However, these benefits are not found to be uniform throughout the network. Their magnitude largely depends on the charge level, the hierarchy of charges across the network, and the difference between the charge levels.     

Socially optimal replacement of conventional with electric vehicles for the US household fleet

In this study, a framework is proposed for minimizing the societal cost of replacing gas-powered household passenger cars with battery electric ones (BEVs). The societal cost consists of operational costs of heterogeneous driving patterns' cars, government investments for charging deployment, and monetized environmental externalities. The optimization framework determines the timeframe needed for conventional vehicles to be replaced with BEVs. It also determines the BEVs driving range during the planning timeframe, as well as the density of public chargers deployed on a linear transportation network over time. We leverage data sets that represent US household driving patterns, as well as the automobile and the energy markets, to apply the model. Results indicate that it takes 8 years for 80% of our conventional vehicle sample to be replaced with electric vehicles, under the base case scenario. The socially optimal all-electric driving range is 204 miles, with chargers placed every 172 miles on a linear corridor. All public chargers should be deployed at the beginning of the planning horizon to achieve greater savings over the years. Sensitivity analysis reveals that the timeframe for the socially optimal conversion of 80% of the sample varies from 6 to 12 years. The optimal decision variables are sensitive to battery pack and vehicle body cost, gasoline cost, the discount rate, and conventional vehicles' fuel economy. Faster conventional vehicle replacement is achieved when the gasoline cost increases, electricity cost decreases, and battery packs become cheaper over the years.     

Electrification of a city bus network—An optimization model for cost-effective placing of charging infrastructure and battery sizing of fast-charging electric bus systems

The deployment of battery-powered electric bus systems within the public transportation sector plays an important role in increasing energy efficiency and abating emissions. Rising attention is given to bus systems using fast charging technology. This concept requires a comprehensive infrastructure to equip bus routes with charging stations. The combination of charging infrastructure and bus batteries needs a reliable energy supply to maintain a stable bus operation even under demanding conditions. An efficient layout of the charging infrastructure and an appropriate dimensioning of battery capacity are crucial to minimize the total cost of ownership and to enable an energetically feasible bus operation. In this work, the central issue of jointly optimizing the charging infrastructure and battery capacity is described by a capacitated set covering problem. A mixed-integer linear optimization model is developed to determine the minimum number and location of required charging stations for a bus network as well as the adequate battery capacity for each bus line. The bus energy consumption for each route segment is determined based on individual route, bus type, traffic, and other information. Different scenarios are examined in order to assess the influence of charging power, climate, and changing operating conditions. The findings reveal significant differences in terms of required infrastructure. Moreover, the results highlight a trade-off between battery capacity and charging infrastructure under different operational and infrastructure conditions. This paper addresses upcoming challenges for transport authorities during the electrification process of the bus fleets and sharpens the focus on infrastructural issues related to the fast charging concept.     

Dually sustainable urban mobility option: Shared-taxi operations with electric vehicles

Electric vehicles (EVs) are energy efficient and often presented as a zero-emission transport mode to achieve long-term decarbonization visions in the transport sector. The implementation of a sustainable transportation environment through EV utilization, however, requires the addressing of certain cost and environmental concerns such as limited driving range and battery-charging issues before its full potential can be realized. Nevertheless, a specific type of use of EVs, namely in taxi services, may elicit positive public opinion, as it promises a commitment toward sustainability in urban life. In light of this, this study proposes an integrated approach that combines EV operation with a conceptual design for shared-ride taxi services. As some productivity loss may be naturally expected due to the time spent in charging, it is important to look at whether such performance loss from the passenger and system standpoints can be offset with ingenuity in operational design. In this study, an EV taxi charge-replenishing scheme that can be coupled with a real-time taxi-dispatch algorithm is designed. The proposed EV charging schemes for taxi services are studied via simulations and the effects of the limited driving range and battery-charging details are examined from a system performance viewpoint. The simulation study also reveals illustrative results on the impact of the EV taxi fleet's operation on the charging system. Next, a real-time shared-taxi operation scheme that allows ride sharing with other passengers is proposed to maximize the operational efficiency. The simulation results suggest that the shared-taxi concept can be a viable option to improve on the limitations caused by EV operation. In addition, the importance of projected charging demands and queue delays at different charging locations are also addressed. Some limitations and a future research agenda are also discussed.