Dynamic traffic congestion pricing and electric vehicle charging management system for the internet of vehicles in smart cities

The integration of the Internet of Vehicles(IoV)in future smart cities could help solve many traffic-related challenges,such as reducing traffic congestion and traffic accidents.Various congestion pricing and electric vehicle charging policies have been introduced in recent years.Nonetheless,the majority of these schemes emphasize penalizing the vehicles that opt to take the congested roads or charge in the crowded charging station and do not reward the vehicles that cooperate with the traffic management system.In this paper,we propose a novel dynamic traffic congestion pricing and electric vehicle charging management system for the internet of vehicles in an urban smart city environment.The proposed system rewards the drivers that opt to take alternative congested-free ways and congested-free charging stations.We propose a token management system that serves as a virtual currency,where the vehicles earn these tokens if they take alternative non-congested ways and charging stations and use the tokens to pay for the charging fees.The proposed system is designed for Vehicular Ad-hoc Networks(VANETs)in the context of a smart city environment without the need to set up any expensive toll collection stations.Through large-scale traffic simulation in different smart city scenarios,it is proved that the system can reduce the traffic congestion and the total charging time at the charging stations.

A modern congestion pricing policy for urban traffic:subsidy plus toll

Congestion pricing is seen as an effective policy to address traffic congestion. In such policies where money, people and authorities are involved, the success generally hinges upon two factors： equity （being fair） and accept- ability （to both people and authorities）. The primary con- cern is the equity, for which ＂tradable credit scheme （TCS）＂ has been introduced and extensively studied in the literature. Nevertheless, due to the com- plexity of the trading schemes, the TCS has yet to find any foot in the real world. To this end, a novel idea of rewarding has substituted the trading component to be known as toll-and-subsidy scheme （TSS）. The idea is to charge the drivers on some roads （toll） while rewarding them to use other alternative--and perhaps underutilized-- roads （subsidy）. The research of the TSS is in its infancy stage. The problem to be tackled in this study is as follows： Given a set of roads constituting a cordon line around the central business district （CBD） or across a screen line, how much toll or subsidy should be assigned to each road？ The problem is first transformed into a capacitated traffic assignment problem. We employ a solution method based on augmenting the travel time of roads up to the level at which the traffic volumes do not exceed some target rates. A real dataset from the city of Winnipeg, Canada, is used as a pilot study. We then discuss policy-related applications of the TSS. It is proved in the literature that one can obtainoptimal TSSs for various objectives and considerations. To this end, the non-negativity of the toll values is relaxed which results in a valid toll set. Nevertheless, the compu- tational time is found to be of highest significance. Our method differs in the fact that the traffic volumes are bounded from the above and it is quite affordable. The main contribution is first to highlight the concept of sub- sidy along with traditional thought of merely toll. Second is to interpret the Lagrangian values of the capacity con- straints as the values of the toll/subsidy.

Optimal Nonlinear Distance Toll for Cordon-Based Congestion Pricing Considering Equity Issue

In order to address the optimal distance toll design problem for cordon-based congestion pricing incorporating the issue of equity,this paper presents a toll user equilibrium( TUE) model based on a transformed network with elastic demand,to evaluate any given toll charge function. A bi-level programming model is developed for determining the optimal toll levels,with the TUE being represented at the lower level.The upper level optimizes the total equity level over the transport network,represented by the Gini coefficient,where a constraint is imposed to the total travel impedance of each OD pair after the levy. A genetic algorithm( GA) is implemented to solve the bi-level model,which is verified by a numerical example.

Congestion Pricing of Urban Street Segments along with MRT Route—The Case Study of Dhaka, Bangladesh

Dhaka, Bangladesh’s capital, already has a congestion problem to handle the ever-growing demand for traffic. The usage of private cars cannot be stopped by charging and the town is not encouraged by quality public transport. It is impossible to enforce congestion prices here in line with traditional cordon pricing systems since the region uses unusual land patterns. However, the current project Mass Rapid Transit (MRT) Line 6, which will be built by 2021, provides the prospect of congestion pricing. A price and optimum approach were established for this article. The congestion price is only payable for the segments and is accessible for private cars under this system. Two urban street segments along the MRT route were selected for the study and congestion toll for a private car is estimated for each segment separately. The sum of the toll in monetary terms is determined using certain associated parameters from the discrepancy from the actual Level of Service (LOS) travel time and traffic flow to the desired LOS. The outcome has shown that the price per passenger car is $0.3 - $0.44. The price is flexible, which means it will vary based on traffic volume. The findings for politicians to enforce congestion pricing are viewed as recommendations.

Allocation of congestion relief cost based on flow change on the congested facilities

Congestion management in an electricity market is introduced in this paper and a new method of allocating congestion cost to transactions is proposed. The proposed method is a two-step process, in which the total congestion cost is firstly allocated to congested facilities and then to each transaction involved. The cost of relieving a congested facility allocated to each transaction is proportional to the power flow change on the congested facility caused by the transaction. The more the power flow change is on the congested facility caused by the transaction, the deeper the degree of involvement by the transaction. Therefore, cutting down the magnitudes of such transactions contributes to relieving congestion. Test results on a 5-bus system indicate that the proposed method can reflect reasonably the degree of involvement by each transaction in the congestion and provide correct price signals contributing to relieving congestion.

Reliability-based congestion pricing model under endogenous equilibrated market penetration and compliance rate of ATIS

A reliability-based stochastic system optimum congestion pricing(SSOCP) model with endogenous market penetration and compliance rate in an advanced traveler information systems(ATIS) environment was proposed. All travelers were divided into two classes. The first guided travelers were referred to as the equipped travelers who follow ATIS advice, while the second unguided travelers were referred to as the unequipped travelers and the equipped travelers who do not follow the ATIS advice(also referred to as non-complied travelers). Travelers were assumed to take travel time, congestion pricing, and travel time reliability into account when making travel route choice decisions. In order to arrive at on time, travelers needed to allow for a safety margin to their trip.The market penetration of ATIS was determined by a continuous increasing function of the information benefit, and the ATIS compliance rate of equipped travelers was given as the probability of the actually experienced travel costs of guided travelers less than or equal to those of unguided travelers. The analysis results could enhance our understanding of the effect of travel demand level and travel time reliability confidence level on the ATIS market penetration and compliance rate; and the effect of travel time perception variation of guided and unguided travelers on the mean travel cost savings(MTCS) of the equipped travelers, the ATIS market penetration, compliance rate, and the total network effective travel time(TNETT).

电力现货市场阻塞费用结算机制分析

节点边际电价价格机制下,试点省份阻塞费用结算机制存在差异,需进行系统的分析。为此,首先从问题的本质出发,梳理了阻塞相关术语的内涵;然后,基于统一的内涵,对比分析了典型现货试点省份阻塞费用结算机制关键异同点;最后,对用户统一结算点电价计算、中长期合约阻塞费收取、阻塞盈余分摊等问题进行分析,提出了相关建议。

Analysis of a joint entry-and distance-based cordon pricing scheme: a dynamic modeling approach

Transportation demand management(TDM)covers strategies for reducing traffic congestion within the affected urban areas. Congestion pricing includes a branch of TDM strategies; among them, the entry-based cordon pricing, i.e., applying charge on entry, is the most popular because of practicality and social acceptance. Many researchers have investigated different second-best approaches for evaluations of cordon pricing plans, mostly by applying static traffic assignment methods. In this paper,a joint entry-and distance-based scheme is proposed to circumvent the deficiencies intrinsic to each. The optimal joint design is considered as the solution to an optimization problem, in which an equilibrium dynamic traffic assignment model is used to take account of flow variations and represent congestion effects more realistically. The problem is solved for the network of Sioux Falls by using an enumeration algorithm, and the solution is compared with those obtained for distinct entry-and distance-based schemes. Based on the results, the joint tolling has the best performance in reducing the total travel time of the travelers and in alleviating the congestion level inside the cordoned area, while generating a higher level of revenue from tolls. Furthermore, the numerical experiments show the unreliability of the results by static against dynamic modeling approach.

Review of Methods to Calculate Congestion Cost Allocation in Deregulated Electricity Market

With maturing deregulated environment for electricity market, cost of transmission congestion becomes a major issue for power system operation. Uniform Marginal Price and Locational Marginal Price (LMP) are the two practical pricing schemes on energy pricing and congestion cost allocation, which are based on different mechanisms. In this paper, these two pricing schemes are introduced in detail respectively. Also, the modified IEEE-14-bus system is used as a test system to calculate the allocated congestion cost by using these two pricing schemes.

电力网络阻塞市场管理机制研究综述

电力市场交易由于电网物理特性,存在着电力网络阻塞的特殊问题。电网阻塞管理措施包括升级设备、优化算法、主动干预与市场价格机制等,通过对国外基于市场体系的电网阻塞管理机制进行梳理,阐述了主要的电价形成机制、输电权定价机制及其对电网阻塞的调节方式,并分析和比较了各自的特点、适用范围与作用机理,从而为完善我国电力市场体系和加强电力资源市场化配置提供理论指引与技术参考。

动态电价机制下电动汽车竞争性充电的阻塞管理模型

针对动态电价机制下大规模电动汽车竞争性充电行为引发的电网安全问题,提出了考虑电网安全约束的电动汽车聚合商阻塞管理模型。首先,分别建立了配电网的无损线性化模型和电动汽车聚合商的集群模型;其次,在动态电价机制下,建立了考虑电网安全约束的电动汽车聚合商竞争性博弈模型;然后,基于变分不等式理论,证明了博弈模型均衡解的存在性和变分解的唯一性;最后,利用梯度下降算法和近端分解算法对博弈模型进行了分布式求解。算例结果表明,该模型可以有效地保障大规模电动汽车竞争性充电时的电网安全。

考虑风电不确定性的主动配电网阻塞管理策略

随着需求侧灵活性资源和风电等分布式资源的快速发展,灵活性资源用电行为的随机性以及风电出力预测的误差,使配网系统潮流发生改变,增加配电网潮流阻塞风险。为了解决风电不确定性造成的配网阻塞问题,研究考虑风电不确定性的主动配电网阻塞管理策略。首先基于Copula函数抽样生成表征风电不确定性的典型出力场景,将不确定变量转化为确定性场景进行优化计算,进而考虑主动配电网元件的运行特性,建立主动配电网双层阻塞管理优化模型。上层模型中,负荷聚合商预测日前电价,基于收集的风电、微型燃气轮机出力信息以用户用电成本最低为目标制定用电需求计划,并上报至配电网系统运营商;下层模型中,配电网系统运营商以总社会利益最大为目标对日前电价进行迭代,以线路功率和节点电压安全为前提求解最优潮流,得到节点边际电价并发布至负荷聚合商,指导其调整日前用电计划;通过上下双层的迭代交互,实现阻塞管理和社会利益最优。最后,通过IEEE 33节点算例进行仿真验证。结果表明:所提阻塞管理策略能保证线路功率和节点电压满足安全约束,有效解决主动配电网的阻塞问题。

基于拥挤定价理论的城际高速铁路浮动定价策略

针对城际高速铁路旅客出行特征较为明显、出行时间较为集中,造成了客流高峰期车厢拥挤、平峰期运量虚靡等问题,提出浮动定价策略.首先,分析拥挤定价理论对于城际高速铁路定价的适用性.其次,给定客流平峰期和高峰期的划分依据,针对高峰期考虑拥挤区段出行的惩罚费用,构建以铁路部门收入最大和旅客出行阻抗效用最小的多目标优化模型;针对客流平峰期考虑旅客对不同运输属性的偏好权重,构建以铁路客票收益最大和广义出行费用最小的双层规划模型.最后,以沪宁城际高速铁路为例进行实证研究.研究结果表明:基于拥挤定价理论的城际高速铁路浮动定价模型能够将原拥挤区段列车满载率由1.02~1.12波动区间降至0.91~0.99波动区间,为均衡优化客流结构提供了可靠保障.

基于金融储能权的市场风险规避方法

随着可再生能源在配电网中的渗透率日益提高,其发电的不确定性和波动性日渐加剧,进而引发线路阻塞等一系列问题。由于线路阻塞引起的电力市场节点边际电价波动,为市场参与者带来了额外的不确定性风险。为此,针对我国电力市场的特点,提出了一种基于金融储能权的阻塞风险规避机制。该机制允许市场参与者通过金融储能权交易来获取以节点边际电价结算的储能使用权,从而有效规避因节点边际电价波动而产生的阻塞风险。然后,设计了基于金融储能权的阻塞风险规避模型,该模型结合节点边际电价和阻塞价格来优化储能的充放电策略及金融储能权的交易策略,旨在实现金融储能权利润的最大化,帮助市场参与者有效规避因线路阻塞引起的风险。以扩展的IEEE 33节点配电网作为仿真案例,仿真结果展示了所提出的阻塞风险规避机制和模型的有效性。

How does trip frequency distort time value to impact congestion charging schemes?

A notable feature of a city or region with close economic and social connections with its neighbours is its highly mixed local and external traffic,and in some cases the external traffic volume is almost as high as that of local traffic.Whilst local traffic volume may be largely made up of the same regular local commuters making frequent trips,external traffic from outside of the city(region)may not be the same people making regular trips to/from the city.However,from a large pool of people making infrequent trips to/from the city,the existence of external traffic is proven by data from the licence plate recognition system of road vehicles in Changde,China.The function of value of time correlated with the income/wage rate and trip frequency is exploited and verified statistically.The time value distorted by trip frequency is defined as perceived time value(PTV),which also influences the way travellers perceive any travel impedance such as congestion delay and toll charges.This paper analyses the price of anarchy(POA)when explicitly considering the travel frequency of the trip-makers and their PTV,and compares with previous analysis without considering travel frequency.We show that when travel frequency is considered,the optimal toll of congested road pricing schemes which converts road traffic flow from user equilibrium into system optimization is much lower than that without considering travel frequency.The cost of licence plate auction cannot be treated as a congestion toll,which is only a threshold of vehicle ownership.That travellers choose routes by PTV rather than TV(time value)is proven by an example of Heishipu Bridge in Changsha,Hunan Province,China.

电力市场阻塞管理综述

在电力市场环境下,为了确保电力系统安全经济运行,需要对输电系统进行有效的管理。阻塞管理是其核心问题。随着电力市场研究的深入,阻塞管理及其定价已成为研究的热点,并发表出版了大量论文和专著。文中对阻塞管理这一领域的研究进行了简要的分类综述,并力图涵盖这一研究领域的各个方面。

关于输电阻塞及其管理的评述

阻塞及阻塞管理是输电可靠性及其控制概念在电力市场环境下的延伸。文中从阻塞管理问题的描述、数学模型、目标函数、约束条件、控制变量和控制策略诸要素出发,诠释阻塞管理的本质,归纳不同类型与不同时间尺度的阻塞管理、阻塞定价和阻塞成本的分摊。讨论阻塞与发电、输电可靠性的关系,评述研究现状和发展方向。指出阻塞管理必须与安全稳定控制(预防、紧急、校正措施)、阻塞调度目标、风险分摊、博弈、市场监管等相结合。

双侧输电阻塞管理与拟Aumann-Shapley定价

该文提出了1种电力联营体模式下输电阻塞管理定价的新方法,首先从总发电成本最低为目标的经济调度结果得到阻塞成本,然后利用阻塞边际成本的概念将阻塞成本分给发电侧和用户侧共同承担,消除了阻塞带来的销售盈余。对用户侧采用了1种类似于Aumann-Shapley法的新方法来进行阻塞定价,保证了按各用户对阻塞的影响大小来分摊阻塞成本。理论分析和示例计算结果表明:与其它仅在用户侧分摊阻塞成本的方法相比,该方法克服了公平性差、对发电侧没有激励信息的缺点,具有较好的经济信息和合理性。

基于统一边际电价结算的电力市场下考虑消除阻塞费用最小的竞价算法

按照统一的边际电价结算,采用排队法进行机组组合,在对组合进去的机组进行负荷分配时考虑了网损的影响。为了消除支路过载,采取调整费用增量最小的方法,即根据各机组灵敏度的大小以及相应的报价曲线使得增加出力的各机组按照相同电价来决定所应增加的出力。它既保证了消除过载又保持了电网的购电费用最小。在灵敏度计算中,使用了直流潮流公式和快速分解法计算潮流的B’矩阵的因子表,简化了计算且能方便地与潮流配合。算例证明了所提算法的正确性。

一种基于市场模型的网络带宽分配方法

价格手段最近被用来控制网络拥塞和管理网络资源的分配，而价格手段的一个重要特点是可以促进资源的合理分配和利用．本文提出一种基于市场模型的网络带宽分配方法．该方法根据用户的带宽需求和网络系统带宽的使用状况，计算出网络带宽的市场价格，并通过用户的价格参数进行带宽资源的协商与分配．分析表明，该方法可以达到优化系统效率和提高用户满意度的目标．