Design scheme for fast charging station for electric vehicles with distributed photovoltaic power generation

The demand for fast charging is increasing owing to the rapid expansion of the market for electric vehicles. In addition, the power generation technology for distributed photovoltaic has matured. This paper presents a design scheme for a fast charging station for electric vehicles equipped with distributed photovoltaic power generation system taking the area with certain conditions in Beijing as an example construction site. The technical indexes and equipment lectotype covering the general framework and subsystems of the charging station are determined by analyzing the charging service demand of fast charging stations. In this study, the layout of the station is developed and the operation benefits of the station is analyzed. The design scheme realizes the design objective of "rationalization, modularization and intelligentization" of the fast charging station and can be used as reference for the construction of a fast charging network in urban area.

Energy-storage configuration for EV fast charging stations considering characteristics of charging load and wind-power fluctuation

Fast charging stations play an important role in the use of electric vehicles(EV)and significantly affect the distribution network owing to the fluctuation of their power.For exploiting the rapid adjustment feature of the energy-storage system(ESS),a configuration method of the ESS for EV fast charging stations is proposed in this paper,which considers the fluctuation of the wind power as well as the characteristics of the charging load.The configuration of the ESS can not only mitigate the effects of fast charging stations on the connected distribution network but also improve its economic efficiency.First,the scenario method is adopted to model the wind power in the distribution network,and according to the characteristics of the EV and the driving probability,the charging demand of each station is calculated.Then,considering factors such as the investment cost,maintenance cost,discharging benefit,and wind curtailment cost,the ESS configuration model of the distribution network is set up,which takes the optimal total costs of the ESS for EV fast charging stations within its lifecycle as an objective.Finally,General Algebraic Modelling System(GAMS)is used to linearize and solve the proposed model.A simulation on an improved IEEE-69 bus system verifies the feasibility and economic efficiency of the proposed model.

考虑负荷空间均衡和充电站合作博弈的快速充电定价机制

为了平衡快速充电负荷空间分布,提高电动汽车用户充电满意度,提出考虑负荷空间均衡和充电站合作博弈的快速充电动态定价机制。首先,通过实际订单数据逆地理编码得到出行概率转移矩阵,结合路网模型和速度-流量模型建立电动汽车充电负荷时空分布模型;然后,考虑用户主观意愿,建立计及用户偏好的充电站选择决策模型,模拟用户对于充电站选择的理性决策行为;最后,以充电站节点负荷均衡性为目标,建立区域内快速充电站合作模式下的动态定价博弈模型,通过迭代算法求解均衡值,并利用Shapley值法对合作联盟所得剩余收益进行分配。仿真实例表明,所提快速充电站动态定价策略能有效降低充电站节点的负荷方差,提高充电桩利用率和充电站收益,并减小用户排队时间,提高用户满意度。

考虑快速充电站影响的前馈功率控制策略

当微电网应对大负荷快速投切时,直流母线容易产生大幅度电压波动,产生大量谐波电流。该问题导致系统效率大大降低,并且威胁系统稳定性。在微电网环境下,当充电功率变化速率过快时,容易导致上述问题。因此针对快速充电站接入微电网中所导致的直流母线电压波动的问题,提出一种含前馈功率的功率控制策略。当用户需要充电时,结合充电汽车的充电特性与用户充电需求,生成前馈功率曲线,再进行充电。通过MATLBAB/Simulink仿真进行对比分析,得出该控制策略控制方式相比于不含前馈功率的控制方式具有相应速度快,直流电压可以快速稳定,并且谐波含量少等优点,具有一定的参考价值。

Coordinated Planning for Fast Charging Stations and Distribution Networks Based on an Improved Flow Capture Location Model

The increasing penetration of plug-in electric vehi-cles(PEVs)should lead to a significant reduction in greenhouse gas emissions.Nevertheless,the development of PEVs is limited by the lack of charging facilities,which is constrained by the coupled transportation-distribution network.This paper presents a stochastic bi-level model for the optimal allocation of fast charging stations(FCSs)and distribution network expansion planning(DNEP).First,a sequential capacitated flow-capturing location-allocation model(SCFCLM)is proposed at the lower level to optimize the allocation of FCSs on the transportation network.Monte-Carlo simulation(MCS)is utilized to estimate daily charging load requirements.Then,we propose an economic model for DNEP at the upper level,and the chance constrained method is employed to relax power flow constraints to address the uncertainties of loads.Numerical experiments are conducted to illustrate the proposed planning method.The influences of the flow capturing sequence and relaxed confidence level on the PEV charging load,FCS planning strategies and DNEP schemes are analyzed.Index Terms-Coordinated planning,fast charging station,flow-capturing model,plug-in electric vehicle,stochastic bi-level model.

Novel Planning Approach for Fast-charging Station in Integrated System

A promising way to boost popularity of electric vehicles(EVs)is to properly layout fast charging stations(FCSs)by jointly considering interactions among EV drivers,power systems and traffic network constraints.This paper proposes a novel sensitivity analysis-based FCS planning approach,which considers the voltage sensitivity of each sub-network in the distribution network and charging service availability for EV drivers in the transportation network.In addition,energy storage systems are optimally installed to provide voltage regulation service and enhance charging capacity.Simulation tests conducted on two distribution network and transportation network coupled systems validate the efficacy of the proposed approach.Moreover,comparison studies demonstrate the proposed approach outperforms a Voronoi graph and particle swarm optimization combined planning approach in terms of much higher computation efficiency.

光伏储能系统在直流快速充电站中的应用

光伏储能系统是一种将太阳能转化为电能并存储起来的技术,在直流快速充电站中有着广阔的应用前景。主要论述光伏储能系统工作原理和光伏储能系统在直流快速充电站中的实践应用,探讨光伏储能系统在直流快速充电站中的挑战,分析光伏储能系统在直流快速充电站中的发展前景。研究表明,光伏储能系统可以减轻电网负荷压力,提高电能利用率,减少对化石燃料的依赖,而系统效率、储能成本和环境适应性是目前急需解决的问题,需要进一步研究和技术革新。

基于stm32f407的直流快速充电桩控制系统的研发

充电桩是新能源汽车行业发展的重要基础设施,随着电动车续航里程的不断提升,对充电容量、快速充电的需求日益攀升。在综合调研国内外充电桩发展的需求后,根据国家对充电桩的现行标准,研发以stm32F407为核心的电动车快速充电桩控制系统。该系统实现桩车信息的互联互通、快速充电,提高充电设施的通用性和开放性,同时设计了直流快速充电桩控制系统检测方案,通过Chroma 8000测量系统测试验证了充电桩控制系统设计方案的可行性。

基于交通-电力均衡耦合的电动汽车快充站与配电网联合规划

针对现有充电站规划大多忽略配电网容量上限,且交通网、快充网以及配电网耦合关系考虑单一导致电动汽车大量接入产生配网负载不均的问题,提出一种基于交通-电力均衡耦合的电动汽车快充站与配电网双层联合规划模型。首先,基于海量网约车订单数据进行数据挖掘和出行特征融合,得到快充负荷时空分布。然后,基于交通网-快充网-配电网之间的信息交互与能量流动关系提出均衡分区耦合模型,并在此基础上建立电动汽车快充站与配电网双层联合规划模型,采用遗传算法与混合整数线性规划相结合的方法求解。最后,基于成都市主城区路网,以54节点配电网为例开展仿真分析,结果表明,提出的双层联合规划模型对于电动汽车快充站规划具有一定的可行性,且均衡耦合模型可以优化配网分区结果,在一定程度上提高了配电网的安全性和稳定性。

基于加油站改造的油电混合能量站多阶段规划策略

随着油改电趋势的持续发展和电动汽车渗透率的提高,传统加油服务商将部分加油站改造为集成加油与快速充电的油电混合能量站是一种颇具前景的战略。针对此趋势,研究城市内油电混合能量站的多阶段规划策略。考虑到长期内电动汽车对传统燃油车的替代和用户补能目的地决策理性,基于用户均衡模型建立栅格化区域中充电或加油需求分布的预测方法。协同考虑快速充电设施的逐步建设和加油设施的拆除,提出含站内储能系统的油电混合能量站的多阶段规划优化模型,并基于布劳威尔不动点定理将其转化为不动点问题形式,进一步通过将充电和加油设施规划解耦,设计一种迭代算法以有效求解规划问题。算例仿真给出的仿真结果表明,所提策略能有效协调充电设施与加油设施建设,适应交通电气化趋势,所采用的均衡需求分配相比传统的社会成本最优的需求分配方法更符合用户理性决策的实际情况,能够获得更加合理的规划方案。

电动汽车充电站有序接入配电网谐波特性分析

针对电动汽车快速充电站接入配电网引起的谐波/间谐波含量偏高的问题,对其谐波/间谐波特性进行了分析。首先对含有电动汽车快速充电站的配电网进行建模,提出了基于粒子群优化算法的电动汽车有序接入配电网优化策略。该策略以降低电动汽车接入配电网谐波含量为目的,对电动汽车接入配电网数目进行智能控制。理论分析了单台及多台电动汽车接入配电网产生的谐波影响,以及多台电动车采用分布式接入与有序接入配电网产生的谐波影响。使用基于粒子群优化算法的电动汽车有序接入配电网的优化策略来控制电动汽车接入电网数目可以有效地降低谐波含量。通过仿真分析验证了其有效性。

Multi-objective simultaneous optimal planning of electric vehiclefast charging stations and DGs in distribution system

The large-scale construction of fast charging stations(FCSs)for electric vehicles(EVs)is helpful inpromoting the EV.It creates a significant challenge for the distribution system operator to determine the optimal planning,especially the siting and sizing of FCSs in the electrical distribution system.Inappropriate planning of fast EV charging stations(EVCSs)cause a negative impact on the distribution system.This paper presented a multiobjective optimization problem to obtain the simultaneous placement and sizing of FCSs and distributed generations(DGs)with the constraints such as the number of EVs in all zones and possible number of FCSs based on the road and electrical network in the proposed system.The problem is formulated as a mixed integer non-linear problem(MINLP)to optimize the loss of EV user,network power loss(NPL),FCS development cost and improve the voltage profile of the electrical distribution system.Non-dominated sorting genetic algorithmⅡ(NSGA-Ⅱ)is used for solving the MINLP.The performance of the proposed technique is evaluated by the 118-bus electrical distribution system.

A Smart Charging Algorithm Based on a Fast Charging Station Without Energy Storage System

With the growing popularity of electric vehicles(EV),there is an urgent demand to solve the stress placed on grids caused by the irregular and frequent access of EVs.The traditional direct current(DC)fast charging station(FCS)based on a photovoltaic(PV)system can effectively alleviate the stress of the grid and carbon emission,but the high cost of the energy storage system(ESS)and the under utilization of the grid-connected interlinking converters(GIC)are not very well addressed.In this paper,the DC FCS architecture based on a PV system and ESS-free is first proposed and employed to reduce the cost.Moreover,the proposed smart charging algorithm(SCA)can fully coordinate the source/load properties of the grid and EVs to achieve the maximum power output of the PV system and high utilization rate of GICs in the absence of ESS support for FCS.SCA contains a self-regulated algorithm(SRA)for EVs and a grid-regulated algorithm(GRA)for GICs.While the DC bus voltage change caused by power fluctuations does not exceed the set threshold,SRA readjusts the charging power of each EV through the status of the charging(SOC)feedback of the EV,which can ensure the power rebalancing of the FCS.The GRA would participate in the adjustment process once the DC bus voltage is beyond the set threshold range.Under the condition of ensuring the charging power of all EVs,a GRA based on adaptive droop control can improve the utilization rate of GICs.At last,the simulation and experimental results are provided to verify the effectiveness of the proposed SCA.

考虑不同类型充电需求的城市内电动汽车充电设施综合规划

电动汽车在城市内的行驶是其主要应用场景,合理规划市内充电设施具有重要的现实意义。私有充电桩慢速充电、公共充电桩的常规充电以及充电站的快速充电是城市内电动汽车的主要充电方式。首先基于电动汽车保有量和行驶统计数据得到电动汽车总充电需求;其次,根据电动汽车用户的充电行为将充电需求分类,对应由不同充电设施满足;随后,抽象出道路网的结构,考虑不同充电设施间的相互影响,基于改进的P中心定位模型建立了一个以总投资成本、运维成本、电量成本和充电站用户成本最小为目标的整数线性规划模型,优化得到各类充电设施的规划方案。算例分析表明,所提方法可以合理满足城市电动汽车充电需求,对私人充电设施配建比例对总成本影响的分析可以更好地指导充电设施的规划。

电动汽车快速充电站需求分析与设备优化方法

电动汽车快速充电站是城市未来重要的基础设施,其规划建设是否合理直接影响到城市交通体系的运行和电动汽车产业的发展.以城市电动汽车日充电量为基础对快速充电站总量进行了预测,通过分析电动汽车快速充电站车辆到达及充电时间的特征,引入了随机服务系统,建立了排队系统模型,计算了平均逗留时间和充电机空闲时间的比例等指标.采用愿望模型分析方法,优化确定充电站的设备数量,既减少顾客的等待时间、解决排队拥挤现象,又有效减少充电站的投资.最后通过MATLAB实例仿真验证了该方法的有效性.

电动汽车快速充电站的储能缓冲系统控制策略

利用储能缓冲系统补偿电动汽车快速充电的脉冲功率,能够减小快速充电站接入对配电网的不利影响。研究含储能缓冲系统的快速充电站结构、不同类型蓄电池的快速充电功率特性,提出计及配电网有功变化率限值的储能缓冲系统运行方式和电流控制策略。结合快速充电站配置,推导储能缓冲系统的运行参数,进而设计储能系统元件参数。利用Matlab/Simulink搭建含储能缓冲系统的快速充电站模型,分析不同电动汽车脉冲充电功率下储能缓冲系统动态特性,验证了所提出控制策略的正确性和有效性。

配置梯次电池储能系统的快速充电站经济性评估

由于电动汽车快速充电站大功率快速充电的特性会对电网的稳定造成冲击,因此考虑在电动车快速充电站中配置电池储能系统(BESS),对充电站负荷进行削峰填谷,从而减少充电站变压器配置容量、缓解大功率快速充电对电网的不利影响。考虑到目前我国大量退役动力电池亟待回收利用的现状,结合梯次利用电池储能系统,建立了基于电动汽车快速充电站整体成本与收益的经济性评估模型,以快速充电站年净收益最大为目标函数,采用改进的遗传算法对模型优化求解。结合算例对快速充电站不配置储能、配置常规电池储能和配置梯次电池储能等不同情况进行了经济性评估,并综合考虑经济性与储能削减负荷的效果,确定了梯次电池储能系统最优容量配置方案。

基于双层优化的电动公交车有序充电策略

随着城市公交车电动化率越来越高,对电网安全稳定运行造成的影响也越来越大,因此对电动公交车的运营规律进行分析并制定合理的充电计划具有十分重要的意义。通过对电动公交车快速充电站运营规律的研究,提出了一种双层优化有序充电控制策略模型,并采用离散二进制粒子群算法进行优化求解。上层模型基于分时电价,从运营商的角度出发,以电动公交车的充电成本最低为目标;下层模型考虑到仅依赖分时电价可能会造成新的负荷高峰,因此从配电网的角度出发,基于上层模型的优化结果并以充电负荷方差最小为目标。最后,通过算例验证了所提模型能够有效减少电动公交车的充电成本,降低车辆充电对配电网所造成的影响。

考虑配网潮流约束的高速公路快速充电站校正规划方法

提出了一种考虑配网潮流约束的高速公路快速充电站校正规划方法。利用电动汽车充电需求预测模型得到高速公路上电动汽车充电需求点的时空分布信息;在此基础上,基于共享型最近邻居聚类算法构建高速公路快速充电站的选址模型,以确定快速充电站的站址方案;进而基于排队论理论和充电需求的时空分布构建快速充电站定容模型,以确定快速充电站的容量配置。对该规划方案下配网潮流约束进行判断,若不满足,则利用所提出的校正原则对规划方案进行修正,直到满足配网的潮流约束为止,以得到最终的快速充电站规划方案。通过典型算例验证了所提规划方法的有效性。

直流配电网中含光伏的电动汽车快速充电站优化配置方案

为在提高直流配电网运行效率的同时降低充电站的投资与运营成本,文中提出了一种含光伏的电动汽车快速充电站的优化配置方法。首先,描述充电站内充电桩、光伏电池、储能系统的能量交换策略,然后,分析DC-DC变流器的电能转换效率-负载率特性,并以系统平均运行效率最高和充电站投资运行成本最低为目标函数建立优化模型,对充电站的接入位置以及各单元的安装容量进行优化。利用改进非支配排序遗传算法(NSGA-Ⅱ)求解该多目标优化的Pareto最优解,得出优化配置方案。最后,以采用双单环结构的中低压直流配电网实际工程为算例,将所提出的优化配置方法与充电站进行扩容的原有扩展规划方案进行对比,验证了所提优化配置方法的有效性和可行性。