CN105844432A

CN105844432A - VANET based electric automobile charge scheduling system and method

Info

Publication number: CN105844432A
Application number: CN201610285940.9A
Authority: CN
Inventors: 苏洲; 惠慧
Original assignee: University of Shanghai for Science and Technology
Current assignee: University of Shanghai for Science and Technology
Priority date: 2016-05-01
Filing date: 2016-05-01
Publication date: 2016-08-10

Abstract

The invention discloses a VANET-based electric vehicle charging scheduling system and method. The system includes an electric vehicle smart meter system, a roadside unit RSU, a server, and a charging station smart meter system; the electric vehicle smart meter system includes a smart meter, a vehicle-mounted GPS positioning device, application unit AU, vehicle-mounted unit OBU, the smart meter system of the charging station includes a smart meter and a charging station control management unit; the method includes that each charging station formulates a charging price according to the geographical location and the queuing situation; The real-time dynamic information of the car calculates the optimal charging station strategy; the user confirms whether to choose charging according to the received optimal strategy, and queues up under the interface of the target charging station through the application unit.

Description

Electric Vehicle Charging Scheduling System and Method Based on VANET

技术领域technical field

本发明属于电动汽车技术领域，更为具体地讲，涉及一种基于VANET(vehicular ad-hocnetwork，车辆自组织网络)的电动汽车充电调度系统及方法。The invention belongs to the technical field of electric vehicles, and more specifically, relates to a charging scheduling system and method for electric vehicles based on VANET (vehicular ad-hocnetwork, vehicle self-organizing network).

背景技术Background technique

随着化石燃料成本的上升以及人类环保意识的增强，电动汽车作为一种绿色交通工具有助于缓和温室气体排放。随着具有间歇性、不可预测性的新能源的大规模引入，带来很大的波动性，给电网的安全稳定运行带来影响，电动汽车的调度有助于缓和这个问题。此外，研究表明用电动汽车代替燃油汽车将带来很大的经济回报。故电动汽车已受到各方关注，并逐渐占据越来越大的市场份额。而大规模的电动汽车不加控制得并入电网也会对电网造成危害，且具有地理优势的充电站往往会吸引更多的充电需求，导致需求的不平衡，故对电动汽车的调度问题也是研究的热点。As the cost of fossil fuels rises and people's awareness of environmental protection increases, electric vehicles, as a green means of transportation, can help alleviate greenhouse gas emissions. With the large-scale introduction of intermittent and unpredictable new energy, it will bring great volatility and affect the safe and stable operation of the power grid. The dispatch of electric vehicles will help alleviate this problem. In addition, studies have shown that replacing gasoline-powered vehicles with electric vehicles will bring great financial rewards. Therefore, electric vehicles have attracted the attention of all parties, and gradually occupy an increasing market share. The uncontrolled integration of large-scale electric vehicles into the grid will also cause harm to the grid, and charging stations with geographical advantages will often attract more charging demand, resulting in unbalanced demand, so the scheduling of electric vehicles is also a problem research hotspot.

由于无线技术和汽车工业的进步以及人们出行习惯，VANET作为一种特殊的移动自组织网络应运而生。VANET可以提高交通安全系数，优化交通流量，减少交通堵塞，提供网络接入以及娱乐应用，数据共享等，给人们的生活带来很大的便利和益处。VANET用于电动汽车的调度可以带来很大的便利，有助于用户更快捷得掌握信息。Due to the advancement of wireless technology and the automobile industry, as well as people's travel habits, VANET emerged as a special mobile ad hoc network. VANET can improve traffic safety, optimize traffic flow, reduce traffic congestion, provide network access, entertainment applications, data sharing, etc., bringing great convenience and benefits to people's lives. The use of VANET in the dispatching of electric vehicles can bring great convenience and help users to grasp information more quickly.

发明内容Contents of the invention

针对以上问题，为了使用户更快捷便利得排队请求充电服务以及平衡充电需求，本发明的目的是提供一种基于VANET的电动汽车充电调度系统及方法，为用户节省时间的同时，提高了电网的稳定性。In view of the above problems, in order to enable users to queue up to request charging services and balance charging needs more quickly and conveniently, the purpose of the present invention is to provide a VANET-based electric vehicle charging scheduling system and method, which saves time for users and improves the efficiency of the power grid. stability.

本发明所采用的技术方案为：The technical scheme adopted in the present invention is:

一种基于VANET的电动汽车充电调度系统，包括电动汽车智能电表系统，路侧单元RSU(road-side unit，路测单元)，服务器，充电站智能电表系统；所述电动汽车智能电表系统包括智能电表SM(smart meter，智能电表)，车载GPS(global position system，全球定位系统)定位装置，应用单元AU(application unit，应用单元)，车载单元OBU(on board unit，车载单元)，所述充电站智能电表系统包括智能电表，充电站控制管理单元；所述电动汽车智能电表系统的智能电表，车载GPS定位装置分别与车载单元有线连接，所述应用单元与车载单元有线或无线连接，所述车载单元与车载单元之间，车载单元与路侧单元分别经V2V(vehicle-to-vehicle，车与车)，V2R(vehicle-to-RSU，车与基站)实现无线通信，所述路侧单元与路侧单元之间是有线连接，所述路侧单元，充电站控制管理单元分别与服务器有线连接，所述充电站智能电表系统的智能电表与充电站控制管理单元之间有线连接。A VANET-based electric vehicle charging dispatching system, comprising an electric vehicle smart meter system, a roadside unit RSU (road-side unit, road test unit), a server, and a charging station smart meter system; the electric vehicle smart meter system includes an intelligent Meter SM (smart meter, smart meter), vehicle-mounted GPS (global position system, Global Positioning System) positioning device, application unit AU (application unit, application unit), vehicle-mounted unit OBU (on board unit, vehicle-mounted unit), the charging The station smart meter system includes a smart meter and a charging station control management unit; the smart meter of the electric vehicle smart meter system, and the vehicle-mounted GPS positioning device are connected to the vehicle-mounted unit by wire, and the application unit is wired or wirelessly connected to the vehicle-mounted unit. Between the vehicle-mounted unit and the vehicle-mounted unit, the vehicle-to-vehicle unit and the roadside unit realize wireless communication through V2V (vehicle-to-vehicle, vehicle and vehicle), V2R (vehicle-to-RSU, vehicle and base station), and the roadside unit There is a wired connection with the roadside unit. The roadside unit and the charging station control management unit are respectively connected to the server by wire. The smart meter of the charging station smart meter system is wired to the charging station control management unit.

其中电动汽车智能电表系统的智能电表的功能是检测电池的电荷状态SoC(state ofcharge，电荷状态)，电动汽车的车速，充放电量以及根据电压和电流波形的相位差判断能量流动的方向，即电动汽车向电网馈送能量还是电网向电动汽车输送能量，根据历史数据与用户输入数据计算用户的充放电习惯，在满足一定电荷状态且符合用户充放电习惯时通过应用单元向用户推送充放电建议；所述车载GPS定位装置用于定位电动汽车所在位置以及提供至目标充电站的最短路径导航；所述应用单元是手机移动应用或是集成于车载单元的嵌入式单元，在电动汽车用户需要充电服务时，直接通过该应用单元排队取号，且具有推送服务，给用户节省了一定的时间；所述车载单元装载在电动汽车上，电动汽车信息在车载单元之间通过V2V无线通信中继转发；所述路侧单元被均匀部署在道路两旁，通过V2R无线通信收集由车载单元传送来的电动汽车信息；所述充电站智能电表系统中的智能电表的功能是采集电网的历史及实时电力价格信息，检测向电动汽车输送的充电量，计算实时排队情况，制定实时充电价格；所述充电站控制管理单元的功能是向服务器传送实时充电站信息，将在应用单元上排队的用户以及到达充电站的用户排入队列；所述服务器根据路侧单元以及充电站控制管理单元输送来的信息计算得到最优充电站策略；所述路侧单元在接收到服务器传送来的最优策略后，经R2V(RSU-to-vehicle，基站与车)和V2V无线通信传送给电动汽车用户。Among them, the function of the smart meter in the electric vehicle smart meter system is to detect the state of charge SoC (state of charge) of the battery, the speed of the electric vehicle, the amount of charge and discharge, and judge the direction of energy flow according to the phase difference between the voltage and current waveforms, that is, Whether the electric vehicle feeds energy to the grid or the grid transmits energy to the electric vehicle, calculate the user's charging and discharging habits based on historical data and user input data, and push charging and discharging suggestions to the user through the application unit when a certain charge state is met and the user's charging and discharging habits are met; The vehicle-mounted GPS positioning device is used to locate the location of the electric vehicle and provide the shortest path navigation to the target charging station; the application unit is a mobile application for a mobile phone or an embedded unit integrated in a vehicle-mounted unit, and when the electric vehicle user needs a charging service When using the application unit, the number is queued directly through the application unit, and it has a push service, which saves a certain amount of time for the user; the vehicle-mounted unit is loaded on the electric vehicle, and the information of the electric vehicle is relayed and forwarded between the vehicle-mounted units through V2V wireless communication; The roadside unit is evenly deployed on both sides of the road, and collects the electric vehicle information transmitted by the on-board unit through V2R wireless communication; the function of the smart meter in the smart meter system of the charging station is to collect the history and real-time power price information of the power grid , detect the amount of charging delivered to the electric vehicle, calculate the real-time queuing situation, and formulate the real-time charging price; the function of the charging station control management unit is to transmit real-time charging station information to the server, and the users who queue up on the application unit and the charging station when they arrive at the charging station The user queues up; the server calculates the optimal charging station strategy according to the information sent by the roadside unit and the charging station control management unit; after the roadside unit receives the optimal strategy sent by the server, the R2V (RSU-to-vehicle, base station and vehicle) and V2V wireless communication are transmitted to electric vehicle users.

当电动汽车智能电表系统的智能电表检测到SoC低于某个预先设定的阈值或符合用户的充电习惯时，电动汽车将考虑充电服务；对应用单元的操作方式可以是按键模式，触屏模式或者声控模式；充电站控制管理单元向服务器发送的实时充电站信息包括位置信息，实时充电价格，附加费用以及排队情况，其中实时充电价格涉及地域差异以及需求调整；充电站控制管理单元功能还可包括向用户推送提醒信息，对推送消息的设置可按照用户的偏好和生活习惯来设定，包括提醒时间起点，提醒间隔时间。同样，当电动汽车智能电表系统的智能电表检测到SoC高于某个预先设定的阈值的同时符合用户向电网馈送能量的习惯时，电动汽车将考虑向电网放电。When the smart meter of the electric vehicle smart meter system detects that the SoC is lower than a preset threshold or meets the user's charging habits, the electric vehicle will consider the charging service; the operation mode of the application unit can be button mode, touch screen mode Or voice control mode; the real-time charging station information sent by the charging station control management unit to the server includes location information, real-time charging price, additional fees and queuing conditions, wherein the real-time charging price involves regional differences and demand adjustments; the charging station control management unit can also function It includes pushing reminder information to the user. The setting of the push message can be set according to the user's preference and living habits, including the starting point of the reminder time and the reminder interval. Similarly, when the smart meter of the electric vehicle smart meter system detects that the SoC is above a certain pre-set threshold while meeting the user's habit of feeding energy to the grid, the electric vehicle will consider discharging to the grid.

本发明就电动汽车充电情况作出讨论。考虑实际情况下不同用户的不同用户特性以及不同的生活习惯，有时用户急于给电动汽车充电，愿以较高的价格寻求优先充电服务，出于人性化考虑，引入优先级，使得寻求优先服务的用户可享受一种非强占式优先服务，但要额外付出一定费用，故将电动汽车用户分为两类：a.寻求优先服务的VIP(very important person，贵宾)用户；b.普通用户。The present invention discusses the electric vehicle charging situation. Considering the different user characteristics and different living habits of different users in the actual situation, sometimes users are eager to charge electric vehicles and are willing to seek priority charging services at a higher price. For the sake of humanization, priority is introduced so that those who seek priority services Users can enjoy a non-preemptive priority service, but they have to pay an extra fee, so electric vehicle users are divided into two categories: a. VIP (very important person, VIP) users who seek priority services; b. Ordinary users.

非强占式优先服务，即具有较高优先级的VIP用户到达充电站时(对于使用应用单元排队的用户即为确认充电选择时)，若充电桩均在提供充电服务，无论接受充电服务的是VIP用户还是普通用户，其都不能强占充电桩。Non-occupancy priority service, that is, when a VIP user with a higher priority arrives at the charging station (for users who use the application unit to queue up, it is when the charging choice is confirmed), if the charging piles are providing charging services, no matter who accepts the charging service VIP users or ordinary users, neither of them can seize the charging pile.

一种基于VANET的电动汽车充电调度方法，包括如下步骤：A method for dispatching electric vehicle charging based on VANET, comprising the steps of:

S100.各充电站的智能电表结合所处地段位置以及电力价格信息，根据当前排队情况，制定实时充电价格，并由充电站控制管理单元向服务器传送实时充电站信息；S100. The smart meters of each charging station combine the location of the location and the electricity price information to formulate a real-time charging price according to the current queuing situation, and the charging station control management unit transmits the real-time charging station information to the server;

S200.当电动汽车智能电表系统中的智能电表检测到SoC低于某阈值或符合用户的充电习惯时，车载单元向服务器发送充电服务需求以及电动汽车实时信息；S200. When the smart meter in the smart meter system of the electric vehicle detects that the SoC is lower than a certain threshold or conforms to the user's charging habit, the on-board unit sends the charging service demand and the real-time information of the electric vehicle to the server;

S300.服务器根据接收到的电动汽车和充电站的实时信息，计算得到电动汽车的最优充电站策略以及函数效用值；S300. The server calculates the optimal charging station strategy and function utility value of the electric vehicle according to the received real-time information of the electric vehicle and the charging station;

S400.车载单元将接收到的最优充电站策略，函数效用值以及该充电站信息通过应用单元推送给用户；S400. The on-board unit pushes the received optimal charging station strategy, function utility value and the charging station information to the user through the application unit;

S500.用户根据自身需求以及对函数效用值的判定选择是否充电，若确认充电选择，直接通过应用单元在目标充电站界面排队取号；S500. The user chooses whether to charge according to his own needs and the judgment of the utility value of the function. If he confirms the charging choice, he directly queues up at the target charging station interface through the application unit to get a number;

S600.目标充电站的充电站控制管理单元接收到由应用单元传送来的排队信息后，将用户排入充电队列；S600. After receiving the queuing information sent by the application unit, the charging station control management unit of the target charging station queues the user into the charging queue;

S700.用户要前往目标充电站时，通过应用单元向车载GPS定位装置发送决策，车载GPS定位装置将提供至目标充电站的最短路径导航。S700. When the user wants to go to the target charging station, the application unit sends a decision to the vehicle-mounted GPS positioning device, and the vehicle-mounted GPS positioning device will provide the shortest path navigation to the target charging station.

在步骤S600后还可以包括步骤S600A：判断用户是否需要推送提醒服务，是，则按用户设置，在特定时间向应用单元发送推送信息；否，则进行步骤S700。Step S600A may also be included after step S600: determine whether the user needs push reminder service, if yes, send push information to the application unit at a specific time according to user settings; if not, proceed to step S700.

所述步骤S100的具体步骤为：The specific steps of the step S100 are:

S110.计算平均排队等待时间，平均排队等待队长；S110. calculate the average queuing waiting time, the average queuing waiting captain;

S120.充电站j根据所处地段设置区域价格f_j ⁽¹⁾，根据排队情况计算需求调整价格f_j ⁽²⁾，加权求得充电价格f_j。S120. The charging station j sets the regional price f _j ⁽¹⁾ according to the location, calculates the demand-adjusted price f _j ⁽²⁾ according to the queuing situation, and obtains the charging price f _j by weighting.

S130.向服务器传送实时充电站信息，包括充电价格，附加费用，位置信息，排队情况。S130. Send real-time charging station information to the server, including charging price, additional fee, location information, and queuing situation.

所述步骤S200中，当SoC低于预定阈值或符合用户的充电习惯时，电动汽车考虑充电，该阈值的设定可由厂家设置，也可由用户自定义。一旦电动汽车智能电表系统中的智能电表检测到SoC低于设定值，则车载单元向服务器发送充电需求以及电动汽车实时信息。实时信息包括实时位置，需求电量，用户权值参数。In the step S200, when the SoC is lower than a predetermined threshold or meets the user's charging habits, the electric vehicle will consider charging. The threshold can be set by the manufacturer or customized by the user. Once the smart meter in the electric vehicle smart meter system detects that the SoC is lower than the set value, the on-board unit sends the charging demand and the real-time information of the electric vehicle to the server. Real-time information includes real-time location, power demand, and user weight parameters.

所述步骤S300的具体步骤为：The specific steps of the step S300 are:

S310.根据用户特性，确定效用函数各项权值以及用户参数取值；S310. According to the characteristics of the user, determine the weights of the utility function and the values of the user parameters;

S320.根据电动汽车以及充电站实时信息计算各充电站对用户的效用值，得到目标函数；S320. Calculate the utility value of each charging station to the user according to the real-time information of the electric vehicle and the charging station, and obtain an objective function;

S330.优化目标函数，得到最优充电站选择策略。S330. Optimizing the objective function to obtain an optimal charging station selection strategy.

本发明具有如下显著优点：The present invention has following remarkable advantage:

借助于VANET环境，允许用户在需要寻求充电服务时，可通过应用单元直接在目标充电站界面下排队取号，节省了一定量的时间。With the help of the VANET environment, when users need to seek charging services, they can directly queue up under the target charging station interface through the application unit, saving a certain amount of time.

调度系统可以设置提醒服务，根据用户的设定向用户发送排队情况的推送消息，无需停留在充电站，在等待充电时间太长的问题上提供了有效方案。The dispatching system can set up a reminder service, and send push messages of the queuing situation to the user according to the user's settings, without having to stay at the charging station, providing an effective solution to the problem of waiting too long for charging.

允许用户在付出额外附加费用的条件下寻求优先服务，为用户提供一种人性化调度方法。Allow users to seek priority services under the condition of paying additional additional fees, providing users with a humanized scheduling method.

考虑地段差异以及需求调整，提出一种定价机制，使充电价格随着排队情况而动态变化，利于调整充电需求，提高电网稳定性。Considering location differences and demand adjustments, a pricing mechanism is proposed to make the charging price dynamically change with the queuing situation, which is conducive to adjusting the charging demand and improving the stability of the power grid.

附图说明Description of drawings

图1为本发明基于VANET的电动汽车充电调度系统的示意图。FIG. 1 is a schematic diagram of the VANET-based electric vehicle charging scheduling system of the present invention.

图2为本发明无推送功能的应用单元界面示意图。Fig. 2 is a schematic diagram of an interface of an application unit without a push function in the present invention.

图3为本发明具备推送功能的应用单元界面示意图。FIG. 3 is a schematic diagram of an interface of an application unit with a push function in the present invention.

图4为本发明无推送功能的基于VANET的电动汽车充电调度方法的流程图。Fig. 4 is a flow chart of the VANET-based electric vehicle charging scheduling method without push function in the present invention.

图5为本发明具备推送功能的基于VANET的电动汽车充电调度方法的流程图。Fig. 5 is a flow chart of the VANET-based electric vehicle charging scheduling method with push function in the present invention.

图6为图4或图5中步骤S100的具体流程图。FIG. 6 is a specific flowchart of step S100 in FIG. 4 or FIG. 5 .

图7为图4或图5中步骤S300的具体流程图。FIG. 7 is a specific flowchart of step S300 in FIG. 4 or FIG. 5 .

具体实施方式detailed description

下面结合附图，对本发明的具体实施例作进一步的详细说明。The specific embodiments of the present invention will be further described in detail below in conjunction with the accompanying drawings.

1、在本实施例中，如图1所示，一种基于VANET的电动汽车充电调度系统，包括电动汽车智能电表系统100，路侧单元200，服务器300，充电站智能电表系统400；所述电动汽车智能电表系统100包括智能电表110，车载GPS定位装置120，应用单元130，车载单元140，所述充电站智能电表系统400包括智能电表410，充电站控制管理单元420；所述智能电表110，车载GPS定位装置120分别与车载单元140有线连接，所述应用单元130与车载单元140有线或无线连接，所述车载单元140与车载单元140之间，车载单元140与路侧单元200分别经V2V，V2R实现无线通信，所述路侧单元200与路侧单元200之间有线连接，所述路侧单元200，充电站控制管理单元420分别与服务器300有线连接，所述智能电表410与充电站控制管理单元420之间有线连接。1. In this embodiment, as shown in FIG. 1 , a VANET-based electric vehicle charging scheduling system includes an electric vehicle smart meter system 100, a roadside unit 200, a server 300, and a charging station smart meter system 400; The electric vehicle smart meter system 100 includes a smart meter 110, a vehicle-mounted GPS positioning device 120, an application unit 130, and a vehicle-mounted unit 140. The charging station smart meter system 400 includes a smart meter 410 and a charging station control management unit 420; the smart meter 110 , the vehicle-mounted GPS positioning device 120 is respectively connected to the vehicle-mounted unit 140 by wire, and the application unit 130 is connected to the vehicle-mounted unit 140 by wire or wirelessly. V2V and V2R realize wireless communication. The roadside unit 200 is connected to the roadside unit 200 by wire. The roadside unit 200 and the charging station control management unit 420 are respectively connected to the server 300 by wire. The station control and management units 420 are connected by wire.

电动汽车智能电表系统100中的智能电表110用于检测电池的电荷状态，电动汽车的车速，充放电量以及根据电压和电流波形的相位差判断能量流动的方向，即电动汽车向电网馈送能量还是电网向电动汽车输送能量，根据历史数据与用户输入数据计算用户的充放电习惯，在满足一定电荷状态且符合用户充放电习惯时通过应用单元130向用户推送充放电建议；车载GPS定位装置120用于定位电动汽车所在位置以及在需要时提供至目标充电站的最短路径导航；车载单元140装载在电动汽车上，用于通过V2V无线通信技术中继转发电动汽车动态信息；路侧单元200被均匀部署在道路两旁，用于通过V2R无线通信技术收集由车载单元140传送来的电动汽车动态信息，并通过有线连接传输至服务器300；充电站智能电表系统400中的智能电表410用于采集电网的历史以及电力价格信息，检测向电动汽车输入的充电量，计算实时排队情况，制定实时充电价格；充电站控制管理单元420的功能包括向服务器300传送实时充电站信息，将在应用单元130上排队的用户以及到达充电站的用户排入队列；服务器300则根据路侧单元200以及充电站控制管理单元420输送来的实时信息计算得到最优充电站策略。路侧单元200在接收到服务器300传送来的最优策略后，经R2V和V2V无线通信技术传送给电动汽车用户。The smart meter 110 in the electric vehicle smart meter system 100 is used to detect the state of charge of the battery, the speed of the electric vehicle, the amount of charge and discharge, and judge the direction of energy flow according to the phase difference between the voltage and current waveforms, that is, whether the electric vehicle is feeding energy to the grid or not. The power grid transmits energy to the electric vehicle, calculates the user's charging and discharging habits based on historical data and user input data, and pushes charging and discharging suggestions to the user through the application unit 130 when a certain charge state is met and meets the user's charging and discharging habits; the vehicle-mounted GPS positioning device 120 uses It is used to locate the location of the electric vehicle and provide the shortest path navigation to the target charging station when needed; the vehicle-mounted unit 140 is loaded on the electric vehicle, and is used to relay and forward the dynamic information of the electric vehicle through V2V wireless communication technology; the roadside unit 200 is uniformly Deployed on both sides of the road, it is used to collect the dynamic information of the electric vehicle transmitted by the on-board unit 140 through V2R wireless communication technology, and transmit it to the server 300 through a wired connection; Historical and power price information, detection of charging amount input to electric vehicles, calculation of real-time queuing conditions, and formulation of real-time charging prices; the functions of the charging station control management unit 420 include sending real-time charging station information to the server 300, and queuing on the application unit 130 The users and the users arriving at the charging station are queued; the server 300 calculates the optimal charging station strategy according to the real-time information sent by the roadside unit 200 and the charging station control management unit 420 . After receiving the optimal strategy from the server 300, the roadside unit 200 transmits it to the electric vehicle user via R2V and V2V wireless communication technologies.

充电站控制管理单元420向服务器300发送的实时充电站信息包括位置信息，实时充电价格，寻求优先服务的附加费用以及排队情况，其中实时充电价格涉及地域差异以及需求调整。The real-time charging station information sent by the charging station control management unit 420 to the server 300 includes location information, real-time charging price, additional fees for seeking priority services, and queuing conditions, wherein the real-time charging price involves regional differences and demand adjustments.

当电动汽车智能电表系统100中的智能电表110检测到电池电荷状态低于某个预先设定的阈值或符合用户的充电习惯时，电动汽车将考虑充电服务，对阈值的设定可为固定值，也可根据用户的生活习惯和实际需求来设定。When the smart meter 110 in the electric vehicle smart meter system 100 detects that the state of charge of the battery is lower than a preset threshold or conforms to the charging habits of the user, the electric vehicle will consider the charging service, and the setting of the threshold can be a fixed value , and can also be set according to the user's living habits and actual needs.

图2为无推送功能的应用单元130界面示意图。FIG. 2 is a schematic diagram of an interface of the application unit 130 without a push function.

在本实施例中，如图2所示，应用单元130可以是手机移动app(application:应用程序)，也可以是集成于车载单元140的嵌入式单元，在电动汽车用户需要充电服务时，可直接通过该应用单元130排队取号，且具有推送服务，给用户节省了一定的时间；对应用单元130的操作方式可以是按键模式，触屏模式或者声控模式。In this embodiment, as shown in Figure 2, the application unit 130 can be a mobile phone app (application: application program), and can also be an embedded unit integrated in the vehicle unit 140. When the electric vehicle user needs a charging service, it can The application unit 130 queues up to get a number directly, and has a push service, which saves a certain amount of time for the user; the operation mode of the application unit 130 can be button mode, touch screen mode or voice control mode.

考虑实际情况下不同用户的不同用户特性以及不同的生活习惯，有时用户急于给电动汽车充电，愿以较高的价格寻求优先充电服务，出于人性化考虑，引入优先级，使得寻求优先服务的用户可享受一种非强占式优先服务，但要额外付出一定费用，故将电动汽车用户分为两类：a.寻求优先服务的VIP用户；b.普通用户。不排除有的用户出于习惯或就近原则考虑，选择直接到充电站排队取号，但本发明涉及的是对使用应用单元130排队取号用户的调度，而只将直接到充电站排队取号的用户作为一种影响因子。Considering the different user characteristics and different living habits of different users in the actual situation, sometimes users are eager to charge electric vehicles and are willing to seek priority charging services at a higher price. For the sake of humanization, priority is introduced so that those who seek priority services Users can enjoy a non-preemptive priority service, but they have to pay a certain fee, so electric vehicle users are divided into two categories: a. VIP users seeking priority services; b. Ordinary users. It is not ruled out that some users choose to go directly to the charging station to queue up to get a number out of habit or the principle of proximity, but the present invention relates to the scheduling of users who use the application unit 130 to queue up to get a number, and only directly go to the charging station to queue up to get a number users as an impact factor.

非强占式优先服务，即具有较高优先级的VIP用户到达充电站时(对于使用应用单元130排队的用户即为确认充电选择时)，若充电桩均在提供充电服务，无论接受充电服务的是VIP用户还是普通用户，其都不能强占充电桩。VIP用户的平均排队等待时间是两部分时间之和：排在前面的VIP用户的平均充电时间总和以及有充电桩空闲下来的平均等待时间；普通用户的平均排队等待时间是三部分之和：排在前面的VIP用户和普通用户的平均充电时间总和、有充电桩空闲下来的平均等待时间以及在等待期间到达的VIP用户的优先服务造成平均耽误时间总和。Non-occupancy priority service, that is, when a VIP user with a higher priority arrives at the charging station (for users who use the application unit 130 to queue up, it is when the charging choice is confirmed), if the charging piles are providing charging services, no matter who accepts the charging service Whether it is a VIP user or an ordinary user, it cannot occupy the charging pile. The average queuing time of VIP users is the sum of two parts: the sum of the average charging time of VIP users in the front and the average waiting time when charging piles are idle; the average queuing time of ordinary users is the sum of three parts: The sum of the average charging time of VIP users and ordinary users in the front, the average waiting time when charging piles are idle, and the sum of the average delay time caused by the priority service of VIP users who arrive during the waiting period.

假定VIP用户和普通用户分别以相互独立的泊松流到达充电站j，则充电站j的用户到达率为：Assuming that VIP users and ordinary users arrive at charging station j with independent Poisson flows, the user arrival rate of charging station j is:

λ_j＝λ_v,j+λ_u,j，λ _j = λ _v,j + λ _u,j ,

式中，λ_j为所有用户到达充电站j的到达率；λ_v,j为VIP用户到达充电站j的到达率；λ_u,j为普通用户到达充电站j的到达率。In the formula, λj is the arrival rate of all users to charging station _j ; λv _,j is the arrival rate of VIP users to charging station j; λu _,j is the arrival rate of ordinary users to charging station j.

则任何时刻，到达充电站j的用户是VIP用户和普通用户的概率分别为λ_v,j/λ_j和λ_u,j/λ_j。Then at any moment, the probabilities of the users arriving at charging station j being VIP users and ordinary users are λ _v,j /λ _j and λ _u,j /λ _j respectively.

又假定充电站j的各充电桩充电是相互独立的，服务时间均服从负指数分布，假定VIP用户和普通用户的平均充电时间相等，则充电站j中所有用户的平均充电时间为：It is also assumed that the charging of each charging pile of charging station j is independent of each other, and the service time is subject to a negative exponential distribution. Assuming that the average charging time of VIP users and ordinary users is equal, the average charging time of all users in charging station j is:

$\overset{&OverBar; &OverBar;}{{ct ct}_{j j}} = = E E. (({ct ct}_{j j})) = = (({λ λ}_{v v,, j j} / / {λ λ}_{j j})) * * ((11 / / {μ μ}_{j j})) + + (({λ λ}_{u u,, j j} / / {λ λ}_{j j})) * * ((11 / / {μ μ}_{j j})) = = 11 / / {μ μ}_{j j},,$

式中，为充电站j中所有用户的平均充电时间；ct_j为充电站j中所有用户的充电时间；μ_j为充电站j的单个充电桩的平均服务率。In the formula, is the average charging time of all users in charging station j; ct _j is the charging time of all users in charging station j; μ _j is the average service rate of a single charging pile in charging station j.

图3为具备推送功能的应用单元130界面示意图。FIG. 3 is a schematic diagram of an interface of the application unit 130 with a push function.

在本实施例中，如图3所示，充电站控制管理单元420功能还可包括向用户推送提醒信息，其中对推送消息的设置可按照用户的偏好和生活习惯来设定，包括提醒时间起点，提醒间隔时间。In this embodiment, as shown in FIG. 3 , the function of the charging station control management unit 420 may also include pushing reminder information to the user, wherein the setting of the push message can be set according to the user's preference and living habits, including the starting point of the reminder time , the reminder interval.

图4，5分别为本发明无推送功能以及具备推送功能的基于VANET的电动汽车充电调度方法的流程图。4 and 5 are flow charts of VANET-based electric vehicle charging scheduling methods without push function and with push function in the present invention, respectively.

在本实施例中，如图4，5所示，基于VANET的电动汽车充电调度方法，包括如下步骤：In this embodiment, as shown in Figures 4 and 5, the VANET-based electric vehicle charging scheduling method includes the following steps:

S100.各充电站的智能电表410结合所处地段位置以及电力价格信息，根据当前排队情况，制定实时充电价格，并由充电站控制管理单元420向服务器300传送实时充电站信息；S100. The smart meter 410 of each charging station combines the location of the location and the electricity price information to formulate a real-time charging price according to the current queuing situation, and the charging station control management unit 420 transmits the real-time charging station information to the server 300;

S200.当电动汽车智能电表系统100中的智能电表110检测到SoC低于某阈值或符合用户的充电习惯时，车载单元140向服务器300发送充电服务需求以及电动汽车实时信息；S200. When the smart meter 110 in the electric vehicle smart meter system 100 detects that the SoC is lower than a certain threshold or conforms to the user's charging habit, the on-board unit 140 sends the charging service demand and the real-time information of the electric vehicle to the server 300;

S300.服务器300根据接收到的电动汽车和充电站的实时信息，计算得到电动汽车的最优充电站策略以及函数效用值；S300. The server 300 calculates the optimal charging station strategy and function utility value of the electric vehicle according to the received real-time information of the electric vehicle and the charging station;

S400.车载单元140将接收到的最优充电站策略，函数效用值以及该充电站信息通过应用单元130推送给用户；S400. The onboard unit 140 pushes the received optimal charging station strategy, function utility value and the charging station information to the user through the application unit 130;

S500.用户根据自身需求以及对函数效用值的判定选择是否充电，若确认充电选择，直接通过应用单元130在目标充电站界面排队取号；S500. The user chooses whether to charge according to his own needs and the judgment of the utility value of the function. If the charging choice is confirmed, the user directly queues up at the target charging station interface through the application unit 130 to get a number;

S600.目标充电站的充电站控制管理单元420接收到由应用单元130传送来的排队信息后，将用户排入充电队列；S600. After receiving the queuing information sent by the application unit 130, the charging station control management unit 420 of the target charging station queues the user into the charging queue;

S700.用户要前往目标充电站时，通过应用单元130向车载GPS定位装置120发送决策，车载GPS定位装置120将提供至目标充电站的最短路径导航。S700. When the user wants to go to the target charging station, the application unit 130 sends a decision to the vehicle-mounted GPS positioning device 120, and the vehicle-mounted GPS positioning device 120 will provide the shortest path navigation to the target charging station.

在步骤S600后还可以包括步骤S600A：判断用户是否需要提醒服务，是，则按用户设置，在特定时间向应用单元130发送推送提醒信息；否，则进行步骤S700。Step S600A may also be included after step S600: determine whether the user needs a reminder service, if yes, send push reminder information to the application unit 130 at a specific time according to user settings; otherwise, proceed to step S700.

在本实施例中，如图6所示，所述步骤S100的具体步骤为：In this embodiment, as shown in FIG. 6, the specific steps of the step S100 are:

S110.计算平均排队等待时间，平均排队等待队长：S110. Calculate the average queuing waiting time, the average queuing waiting captain:

当所有充电桩都在提供服务时，无论到达充电站的是VIP用户还是普通用户，都需要等待充电桩空闲下来。充电桩的占用无关用户类别，故等待有充电桩空闲下来的平均时间应根据充电站服务时间分布来计算，而VIP用户和普通用户的平均充电时间相等，故在计算充电桩空闲下来的平均等待时间时，与用户的排队顺序无关，也无需考虑用户类别。When all the charging piles are providing services, no matter whether it is a VIP user or an ordinary user who arrives at the charging station, they need to wait for the charging pile to be free. The occupancy of charging piles has nothing to do with user categories, so the average waiting time for charging piles to be idle should be calculated according to the service time distribution of charging stations, and the average charging time for VIP users and ordinary users is equal, so when calculating the average waiting time for charging piles to be idle Time, it has nothing to do with the user's queuing order, and there is no need to consider the user category.

由爱尔兰延迟公式得，当用户到达充电站j后，该充电站的各充电桩均在提供充电服务的概率为：According to the Irish delay formula, when the user arrives at the charging station j, the probability that all the charging piles of the charging station are providing charging services is:

${Σ Σ}_{{n no}_{j j} = = {N N}_{j j}}^{∞ ∞} {p p}_{{n no}_{j j}} = = \frac{{p p}_{{N N}_{j j}}}{11 - - {ρ ρ}_{j j}},,$

其中， in,

ρ_j＝λ_j/(μ_j*N_j)＝ρ_1j/N_j，ρ_1j＝ρ_v,j+ρ_u,j＝λ_v,j/μ_j+λ_u,j/μ_j＝λ_j/μ_j，ρ _j =λ _j /(μ _j *N _j )=ρ _1j /N _j , ρ _1j =ρ _v,j +ρ _u,j =λ _v,j /μ _j +λ _u,j /μ _j =λ _j / μ _j ,

ρ_v,j＝λ_v,j/μ_j，ρ_u,j＝λ_u,j/μ_j，ρ _v,j = λ _v,j /μ _j , ρ _u,j = λ _u,j /μ _j ,

式中，n_j为充电站j中所有用户的个数；N_j为充电站j的充电桩数量；p_nj为充电站j中所有用户个数为n_j的概率；为充电站j的所有用户个数为N_j的概率；ρ_j为充电站j的服务强度；p_0j为充电站j中所有用户个数为0的概率；ρ_1j为充电站j中单个充电桩对所有用户的充电服务强度；ρ_v,j为充电站j中单个充电桩对VIP用户的充电服务强度；ρ_u,j为充电站j中单个充电桩对普通用户的充电服务强度。In the formula, n _j is the number of all users in charging station j; N _j is the number of charging piles in charging station j; p _nj is the probability that the number of all users in charging station j is n _j ; is the probability that the number of all users of charging station j is N _j ; ρ _j is the service intensity of charging station j; p _0j is the probability that the number of all users in charging station j is 0; ρ _1j is the single charging ρv _,j is the charging service intensity of a single charging pile in charging station j for VIP users; ρu _,j is the charging service intensity of a single charging pile in charging station j for ordinary users.

则任一用户等待有充电桩空闲下来的平均时间为：Then the average time for any user to wait for a charging pile to be idle is:

${Σ Σ}_{{n no}_{j j} = = {N N}_{j j}}^{∞ ∞} {p p}_{{n no}_{j j}} * * E E. (({et et}_{j j})) = = {Σ Σ}_{{n no}_{j j} = = {N N}_{j j}}^{∞ ∞} {p p}_{{n no}_{j j}} * * \overset{&OverBar; &OverBar;}{{et et}_{j j}} = = \frac{{p p}_{{N N}_{j j}}}{11 - - {ρ ρ}_{j j}} * * \overset{&OverBar; &OverBar;}{{et et}_{j j}},,$

式中，et_j为充电站j的剩余服务时间，即当用户到达充电站j时，若N_j个充电桩均被占用，则还要经历et_j才能空出一个充电桩来为下一个用户提供充电服务；为充电站j的平均剩余服务时间。In the formula, et _j is the remaining service time of charging station j, that is, when the user arrives at charging station j, if N _j charging piles are all occupied, it will take et _j to free a charging pile for the next user provide charging services; is the average remaining service time of charging station j.

由于在计算充电桩空闲下来的平均等待时间时，不区分用户类别，则用户排队等待时间是两部分时间之和：排在前面的用户平均充电时间总和以及有充电桩空闲下来的平均等待时间：Since the average waiting time for charging piles to be idle is not distinguished by user category, the waiting time for users in line is the sum of two parts: the sum of the average charging time of users in the front and the average waiting time for charging piles that are idle:

排在前面的用户平均充电时间总和为：The sum of the average charging time of the top users is:

$\overset{&OverBar; &OverBar;}{{ct ct}_{j j}} * * {lq lq}_{j j} = = {lq lq}_{j j} / / {μ μ}_{j j} = = {ρ ρ}_{11 j j} * * {wq w}_{j j},,$

其中，lq_j＝λ_j*wq_j，Among them, lq _j =λ _j *wq _j ,

式中，lq_j为充电站j中排队等待充电服务的所有用户的平均个数。In the formula, lq _j is the average number of all users waiting in line for charging service in charging station j.

有充电桩空闲下来的平均等待时间为 The average waiting time for charging piles to be idle is

得，have to,

${wq w}_{j j} = = \frac{{p p}_{{N N}_{j j}}}{11 - - {ρ ρ}_{j j}} * * \overset{&OverBar; &OverBar;}{{et et}_{j j}} + + {ρ ρ}_{11 j j} * * {wq w}_{j j},,$

得，have to,

$\overset{&OverBar; &OverBar;}{{et et}_{j j}} = = \frac{((11 - - {ρ ρ}_{j j})) * * ((11 - - {ρ ρ}_{11 j j}))}{{p p}_{{N N}_{j j}}} * * {wq w}_{j j},,$

式中，wq_j为充电站j中所有用户的平均排队等待时间。In the formula, wq _j is the average queuing waiting time of all users in charging station j.

由M/M/N_j等待制排队模型的推导结论得：From the derivation conclusion of the M/M/N _j waiting system queuing model:

${wq w}_{j j} = = \frac{{(({ρ ρ}_{j j} * * {N N}_{j j}))}^{{N N}_{j j}} * * {p p}_{00 j j}}{{μ μ}_{j j} * * {N N}_{j j} * * {N N}_{j j}!! * * {((11 - - {ρ ρ}_{j j}))}^{22}},,$

得，have to,

$\overset{&OverBar; &OverBar;}{{et et}_{j j}} = = \frac{((11 - - {ρ ρ}_{j j})) * * ((11 - - {ρ ρ}_{11 j j}))}{{p p}_{{N N}_{j j}}} * * \frac{{(({ρ ρ}_{j j} * * {N N}_{j j}))}^{{N N}_{j j}} * * {p p}_{00 j j}}{{μ μ}_{j j} * * {N N}_{j j} * * {N N}_{j j}!! * * {((11 - - {ρ ρ}_{j j}))}^{22}} = = \frac{11 - - {N N}_{j j} * * {ρ ρ}_{j j}}{{μ μ}_{j j} * * {N N}_{j j} * * ((11 - - {ρ ρ}_{j j}))},,$

则有充电桩空闲下来的平均等待时间为：Then the average waiting time for charging piles to be idle is:

$\frac{{p p}_{{N N}_{j j}}}{11 - - {ρ ρ}_{j j}} * * \overset{&OverBar; &OverBar;}{{et et}_{j j}} = = \frac{{p p}_{{N N}_{j j}}}{11 - - {ρ ρ}_{j j}} * * \frac{11 - - {N N}_{j j} * * {ρ ρ}_{j j}}{{μ μ}_{j j} * * {N N}_{j j} * * ((11 - - {ρ ρ}_{j j}))},,$

A.计算当VIP用户排入充电站j的队列时平均排队等待时间，平均排队等待队长：A. Calculate the average queuing time and the average queuing team leader when VIP users enter the queue of charging station j:

VIP用户不能强占正在提供充电服务的充电桩，只能排在普通用户前面，其平均排队等待时间由两部分构成：VIP users cannot forcibly occupy the charging piles that are providing charging services, and can only be ranked in front of ordinary users. The average queuing time consists of two parts:

1)排在前面的VIP用户平均充电时间总和：1) The sum of the average charging time of the top VIP users:

$\overset{&OverBar; &OverBar;}{{ct ct}_{v v,, j j}} * * {lq lq}_{v v,, j j} = = \overset{&OverBar; &OverBar;}{{ct ct}_{j j}} * * {lq lq}_{v v,, j j} = = {lq lq}_{v v,, j j} / / {μ μ}_{j j} = = {ρ ρ}_{v v,, j j} * * {wq w}_{v v,, j j},,$

其中，lq_v,j＝λ_v,j*wq_v,j，Among them, lq _v,j =λ _v,j *wq _v,j ,

式中，为充电站j中VIP用户的平均充电时间；lq_v,j为充电站j中VIP用户平均排队等待队长；wq_v,j为充电站j中VIP用户的平均排队等待时间。In the formula, is the average charging time of VIP users in charging station j; lq _v,j is the average queue length of VIP users in charging station j; wq _v,j is the average queuing time of VIP users in charging station j.

2)有充电桩空闲下来的平均等待时间为 2) The average waiting time for charging piles to be idle is

得：have to:

${wq w}_{v v,, j j} = = {ρ ρ}_{v v,, j j} * * {wq w}_{v v,, j j} + + \frac{{p p}_{{N N}_{j j}}}{11 - - {ρ ρ}_{j j}} * * \overset{&OverBar; &OverBar;}{{et et}_{j j}} = = {ρ ρ}_{v v,, j j} * * {wq w}_{v v,, j j} + + \frac{{p p}_{{N N}_{j j}}}{11 - - {ρ ρ}_{j j}} * * \frac{11 - - {N N}_{j j} * * {ρ ρ}_{j j}}{{μ μ}_{j j} * * {N N}_{j j} * * ((11 - - {ρ ρ}_{j j}))},,$

则VIP用户在充电站j的平均排队等待时间以及平均排队等待队长分别为：Then the average queuing time and the average queuing team leader of VIP users at charging station j are:

${wq w}_{v v,, j j} = = \frac{{p p}_{{N N}_{j j}}}{11 - - {ρ ρ}_{v v,, j j}} * * \frac{11 - - {N N}_{j j} * * {ρ ρ}_{j j}}{{μ μ}_{j j} * * {N N}_{j j} * * {((11 - - {ρ ρ}_{j j}))}^{22}},,$

${lq lq}_{v v,, j j} = = {λ λ}_{v v,, j j} * * {wq w}_{v v,, j j} = = {λ λ}_{v v,, j j} * * \frac{{p p}_{{N N}_{j j}}}{11 - - {ρ ρ}_{v v,, j j}} * * \frac{11 - - {N N}_{j j} * * {ρ ρ}_{j j}}{{μ μ}_{j j} * * {N N}_{j j} * * {((11 - - {ρ ρ}_{j j}))}^{22}},,$

其中： in:

ρ_j＝λ_j/(μ_j*N_j)，ρ_v,j＝λ_v,j/μ_j，λ_j＝λ_v,j+λ_u,j，ρ _j =λ _j /(μ _j *N _j ), ρ _v,j =λ _v,j /μ _j , λ _j =λ _v,j +λ _u,j ,

B.计算当普通用户排入充电站j的队列时平均排队等待时间，平均排队等待队长：B. Calculate the average queuing time when ordinary users enter the queue of charging station j, and the average queuing team leader:

普通用户的平均排队等待时间由三部分构成：The average queuing waiting time of ordinary users consists of three parts:

1)排在前面的VIP用户和普通用户的平均充电时间总和分别为：1) The sum of the average charging time of the top VIP users and ordinary users is respectively:

$\overset{&OverBar; &OverBar;}{{ct ct}_{u u,, j j}} * * {lq lq}_{u u,, j j} = = \overset{&OverBar; &OverBar;}{{ct ct}_{j j}} * * {lq lq}_{u u,, j j} = = {lq lq}_{u u,, j j} / / {μ μ}_{j j} = = {ρ ρ}_{u u,, j j} * * {wq w}_{u u,, j j},,$

其中，lq_v,j＝λ_v,j*wq_v,j，lq_u,j＝λ_u,j*wq_u,j，Among them, lq _v,j =λ _v,j *wq _v,j , lq _u,j =λ _u,j *wq _u,j ,

式中，为充电站j中普通用户的平均充电时间；lq_u,j为充电站j中普通用户平均排队等待队长；wq_u,j为充电站j中普通用户的平均排队等待时间。In the formula, is the average charging time of ordinary users in charging station j; lq _u,j is the average queuing queue length of ordinary users in charging station j; wq _u,j is the average queuing waiting time of ordinary users in charging station j.

3)在等待期间到达的VIP用户的优先服务造成的平均耽误时间总和：3) The sum of the average delay time caused by the priority service of VIP users arriving during the waiting period:

VIP用户具有优先服务特权，在普通用户被排入队列至其接受充电服务期间，若有VIP用户到达充电站j，则VIP用户将被优先排在该普通用户前面。由于在普通用户所需排队等待时间wq_u,j期间，VIP用户到达的平均人数为wq_u,j*λ_v,j，则其需要的平均充电时间总和为：VIP users have priority service privileges. During the period from ordinary users being queued to receiving charging services, if a VIP user arrives at charging station j, the VIP user will be prioritized in front of the ordinary user. Since the average number of VIP users arriving during the queuing time wq _u,j required by ordinary users is wq _u,j *λ _v,j , the sum of the average charging time required is:

${wq w}_{u u,, j j} * * {λ λ}_{v v,, j j} * * \overset{&OverBar; &OverBar;}{{ct ct}_{v v,, j j}} = = {wq w}_{u u,, j j} * * {ρ ρ}_{v v,, j j},,$

得，have to,

${wq w}_{u u,, j j} = = {ρ ρ}_{v v,, j j} * * {wq w}_{v v,, j j} + + {ρ ρ}_{u u,, j j} * * {wq w}_{u u,, j j} + + \frac{{p p}_{{N N}_{j j}}}{11 - - {ρ ρ}_{j j}} * * \frac{11 - - {N N}_{j j} * * {ρ ρ}_{j j}}{{μ μ}_{j j} * * {N N}_{j j} * * ((11 - - {ρ ρ}_{j j}))} + + {wq w}_{u u,, j j} * * {ρ ρ}_{v v,, j j},,$

则普通用户在充电站j的平均排队等待时间以及平均排队等待队长分别为：Then the average queuing time and the average queuing team leader of ordinary users at charging station j are:

$\begin{matrix} {wq w}_{u u,, j j} = = \frac{{p p}_{{N N}_{j j}}}{11 - - {ρ ρ}_{j j}} * * \frac{11 - - {N N}_{j j} * * {ρ ρ}_{j j}}{{μ μ}_{j j} * * {N N}_{j j} * * ((11 - - {ρ ρ}_{j j}))} * * \frac{11}{11 - - {ρ ρ}_{u u,, j j} - - {ρ ρ}_{v v,, j j}} + + \frac{{ρ ρ}_{v v,, j j}}{11 - - {ρ ρ}_{u u,, j j} - - {ρ ρ}_{v v,, j j}} * * {wq w}_{v v,, j j} \\ = = \frac{{p p}_{{N N}_{j j}}}{11 - - {ρ ρ}_{j j}} * * \frac{11}{{μ μ}_{j j} * * {N N}_{j j} * * ((11 - - {ρ ρ}_{j j}))} + + \frac{{p p}_{{N N}_{j j}}}{11 - - {ρ ρ}_{v v,, j j}} * * \frac{{ρ ρ}_{v v,, j j}}{{μ μ}_{j j} * * {N N}_{j j} * * {((11 - - {ρ ρ}_{j j}))}^{22}} \end{matrix},,$

${lq lq}_{u u,, j j} = = {λ λ}_{u u,, j j} * * {wq w}_{u u,, j j} = = {λ λ}_{u u,, j j} * * ((\frac{{p p}_{{N N}_{j j}}}{11 - - {ρ ρ}_{j j}} * * \frac{11}{{μ μ}_{j j} * * {N N}_{j j} * * ((11 - - {ρ ρ}_{j j}))} + + \frac{{p p}_{{N N}_{j j}}}{11 - - {ρ ρ}_{v v,, j j}} * * \frac{{ρ ρ}_{v v,, j j}}{{μ μ}_{j j} * * {N N}_{j j} * * {((11 - - {ρ ρ}_{j j}))}^{22}})),,$

其中， in,

ρ_j＝λ_j/(μ_j*N_j)，ρ_u,j＝λ_u,j/μ_j，ρ_v,j＝λ_v,j/μ_j，λ_j＝λ_v,j+λ_u,j，ρ _j =λ _j /(μ _j *N _j ), ρ _u,j =λ _u,j /μ _j , ρ _v,j =λ _v,j /μ _j ,λ _j =λ _v,j +λ _{u , j} ,

由以上计算过程，可得充电站j中排队等待充电服务的所有用户的平均个数为：From the above calculation process, it can be obtained that the average number of all users queuing up for charging service in charging station j is:

$\begin{matrix} {lq lq}_{j j} = = {lq lq}_{v v,, j j} + + {lq lq}_{u u,, j j} = = {λ λ}_{v v,, j j} * * {wq w}_{v v,, j j} + + {λ λ}_{u u,, j j} * * {wq wxya}_{u u,, j j} \\ = = {λ λ}_{v v,, j j} * * \frac{{p p}_{{N N}_{j j}}}{11 - - {ρ ρ}_{v v,, j j}} * * \frac{11 - - {N N}_{j j} * * {ρ ρ}_{j j}}{{μ μ}_{j j} * * {N N}_{j j} * * {((11 - - {ρ ρ}_{j j}))}^{22}} + + {λ λ}_{u u,, j j} * * ((\frac{{p p}_{{N N}_{j j}}}{11 - - {ρ ρ}_{j j}} * * \frac{11}{{μ μ}_{j j} * * {N N}_{j j} * * ((11 - - {ρ ρ}_{j j}))} + + \frac{{p p}_{{N N}_{j j}}}{11 - - {ρ ρ}_{v v,, j j}} * * \frac{{ρ ρ}_{v v,, j j}}{{μ μ}_{j j} * * {N N}_{j j} * * {((11 - - {ρ ρ}_{j j}))}^{22}})) \end{matrix} . .$

S120.充电站j根据所处地段设置区域价格f_j ⁽¹⁾，根据排队情况计算需求调整价格f_j ⁽²⁾，加权求得充电价格f_j：S120. Charging station j sets the regional price f _j ⁽¹⁾ according to the location, calculates the demand-adjusted price f _j ⁽²⁾ according to the queuing situation, and obtains the charging price f _j by weighting:

地处有利位置的充电站往往可以吸引更多的顾客，也就可以设置更高的充电价格，基于此，本发明将地区按照某种准则划分为z个区域，且同一区域内充电站的区域价格f_j ⁽¹⁾相等。划分的准则比如客流量，离市中心的距离，是否为住宅区，商业区或工业区等。A charging station in a favorable location can often attract more customers, and thus can set a higher charging price. Based on this, the present invention divides the region into z regions according to a certain criterion, and the charging stations in the same region The prices f _j ⁽¹⁾ are equal. Criteria for division such as passenger flow, distance from the city center, whether it is a residential area, commercial area or industrial area, etc.

按照所定义的准则，充电站的区域价格f_j ⁽¹⁾为：According to the defined criterion, the regional price f _j ⁽¹⁾ of the charging station is:

f_j ⁽¹⁾＝f_z f _j ⁽¹⁾ = f _z

式中，f_z为区域z中充电站的区域价格。where f _z is the regional price of charging stations in area z.

为了调整充电需求，使各充电站的用户到达率接近最优值，充电价格随着排队情况而动态变化，即实际排队等待队长大于最优值下对应的排队等待队长，则抬高充电价格；实际排队等待队长小于最优值下对应的排队等待队长，则降低充电价格。最优到达率可根据充电站的充电桩个数，服务强度，电网负荷等来设定。In order to adjust the charging demand, so that the user arrival rate of each charging station is close to the optimal value, the charging price changes dynamically with the queuing situation, that is, the actual queuing length is greater than the corresponding queuing length under the optimal value, and the charging price is raised; If the actual queuing length is less than the corresponding queuing length under the optimal value, the charging price will be reduced. The optimal arrival rate can be set according to the number of charging piles in the charging station, service intensity, grid load, etc.

根据排队情况计算的需求调整价格f_j ⁽²⁾为：The demand-adjusted price f _j ⁽²⁾ calculated according to the queuing situation is:

${f f}_{j j}^{((22))} = = {f f}_{j j}^{((22))} \frac{{lq lq}_{j j} (({λ λ}_{v v,, j j},, {λ λ}_{u u,, j j})) - - {lq lq}_{j j}^{* *} (({λ λ}_{v v,, j j}^{* *},, {λ λ}_{u u,, j j}^{* *}))}{{lq lq}_{j j}^{* *} (({λ λ}_{v v,, j j}^{* *},, {λ λ}_{u u,, j j}^{* *}))},,$

式中，lq_j(λ_v,j,λ_u,j)为实际的平均排队等待队长；lq_j ^*(λ_v,j ^*,λ_u,j ^*)为最优到达率下平均排队等待队长。In the formula, lq _j (λ _v,j ,λ _u,j ) is the actual average queue length; lq _j ^* (λ _v,j ^* ,λ _u,j ^* ) is the average queue length under the optimal arrival rate .

其中，需求调整价格函数应满足：Among them, the demand-adjusted price function should satisfy:

1)函数值随着lq_j(λ_v,j,λ_u,j)的增大而增大；1) The function value increases with the increase of lq _j (λ _v,j ,λ _u,j );

2) 2)

举例说明，for example,

${f f}_{j j}^{((22))} = = {k k}_{j j} * * \frac{{lq lq}_{j j} (({λ λ}_{v v,, j j},, {λ λ}_{u u,, j j})) - - {lq lq}_{j j}^{* *} (({λ λ}_{v v,, j j}^{* *},, {λ λ}_{u u,, j j}^{* *}))}{{lq lq}_{j j}^{* *} (({λ λ}_{v v,, j j}^{* *},, {λ λ}_{u u,, j j}^{* *}))},,$

式中，k_j为需求调整价格函数的斜率。In the formula, k _j is the slope of the demand-adjusted price function.

则充电价格函数为：Then the charging price function is:

${f f}_{j j} = = {β β}_{j j}^{((11))} * * {f f}_{z z} + + {β β}_{j j}^{((22))} * * {f f}_{j j}^{((22))} ((\frac{{lq lq}_{j j} (({λ λ}_{v v,, j j},, {λ λ}_{u u,, j j})) - - {lq lq}_{j j}^{* *} (({λ λ}_{v v,, j j}^{* *},, {λ λ}_{u u,, j j}^{* *}))}{{lq lq}_{j j}^{* *} (({λ λ}_{v v,, j j}^{* *},, {λ λ}_{u u,, j j}^{* *}))})) . .$

其中，满足β_j ⁽¹⁾+β_j ⁽²⁾＝1，β_j ⁽¹⁾≥0，β_j ⁽²⁾≥0，Among them, satisfy β _j ⁽¹⁾ + β _j ⁽²⁾ = 1, β _j ⁽¹⁾ ≥ 0, β _j ⁽²⁾ ≥ 0,

式中，β_j ⁽¹⁾，β_j ⁽²⁾为充电站j权值系数。In the formula, β _j ⁽¹⁾ and β _j ⁽²⁾ are the weight coefficients of charging station j.

S130.向服务器300传送实时充电站信息，包括充电价格，附加费用，位置信息，排队情况。S130. Send real-time charging station information to the server 300, including charging price, additional fee, location information, and queuing situation.

在本实施例中，如图7所示，所述步骤S300的具体步骤为：In this embodiment, as shown in FIG. 7, the specific steps of step S300 are:

S310.根据用户特性，确定效用函数各项权值以及用户参数取值：S310. According to the characteristics of the user, determine the weights of the utility function and the values of the user parameters:

用户i选择充电站j的效用函数为：The utility function for user i to choose charging station j is:

U_i,j＝z_i-α_i ⁽¹⁾*l_i,j-α_i ⁽²⁾*(b_i,j*wq_v,j+(1-b_i,j)*wq_u,j)-α_i ⁽³⁾*(f_j+b_i,j*c_j)，U _i,j ＝z _i -α _i ⁽¹⁾ *l _i,j -α _i ⁽²⁾ *(b _i,j *wq _v,j +(1-b _i,j )*wq _u,j ) -α _i ⁽³⁾ *(f _j +b _i,j *c _j ),

其中，满足z_i≥0，α_i ⁽¹⁾+α_i ⁽²⁾+α_i ⁽³⁾＝1，α_i ⁽¹⁾≥0，α_i ⁽²⁾≥0，α_i ⁽³⁾≥0，b_i,j∈{0,1}，Where z _i ≥ 0, α _i ⁽¹⁾ + α _i ⁽²⁾ + α _i ⁽³⁾ = 1, α _i ⁽¹⁾ ≥ 0, α _i ⁽²⁾ ≥ 0, α _i ⁽³⁾ ≥ 0, b _i,j ∈ {0,1},

式中，z_i为用户i的充电意愿参数；α_i ⁽¹⁾，α_i ⁽²⁾，α_i ⁽³⁾为用户i的权值参数；l_i,j为用户i所在位置到充电站j的距离；b_i,j为用户i是否选择寻求优先服务，即是否选择成为VIP用户，b_i,j＝1则为VIP用户，b_i,j＝0则为普通用户；wq_v,j为VIP用户平均排队等待时间；wq_u,j为普通用户平均排队等待时间；f_j为充电站j的充电价格；c_j为在充电站j寻求优先服务需要额外付出的费用。In the formula, z _i is the charging willingness parameter of user _i ; α _i ⁽¹⁾ , α _i ⁽²⁾ and α _i ⁽³⁾ are the weight parameters of user i; j distance; b _{i, j} is whether user i chooses to seek priority service, that is, whether to choose to become a VIP user, b _{i, j} = 1 means VIP user, b _{i, j} = 0 means ordinary user; wq _{v, j} is the average queuing time of VIP users; wq _u,j is the average queuing time of ordinary users; f _j is the charging price of charging station j; c _j is the additional cost for seeking priority service at charging station j.

其中，z_i，α_i ⁽¹⁾，α_i ⁽²⁾，α_i ⁽³⁾可以由用户在应用单元130界面上设定，也可以根据用户历史数据估计；c_j由充电站来设定；b_i,j由优化计算得到。Among them, _zi , α _i ⁽¹⁾ , α _i ⁽²⁾ , α _i ⁽³⁾ can be set by the user on the interface of the application unit 130, or can be estimated according to the user's historical data; c _j is set by the charging station ; b _{i, j} are obtained by optimization calculation.

S320.根据电动汽车以及充电站实时信息计算各充电站对用户的效用值，得到目标函数：S320. Calculate the utility value of each charging station to the user according to the real-time information of the electric vehicle and the charging station, and obtain the objective function:

目标函数为：The objective function is:

$max max {U u}_{i i} = = m m a a x x {Σ Σ}_{j j = = 11}^{J J} {U u}_{i i,, j j} * * {x x}_{i i,, j j},,$

其中，满足 Among them, satisfy

式中，J为充电站个数；x_i,j为二进制选择变量，x_i,j＝1则用户i选择充电站j，x_i,j＝0则用户i不选择充电站j。In the formula, J is the number of charging stations; _xi,j is a binary selection variable, if _xi,j = 1, user i chooses charging station j, and if _xi,j = 0, user i does not choose charging station j.

S330.优化目标函数，得到最优充电站选择策略：S330. Optimizing the objective function to obtain the optimal charging station selection strategy:

通过优化算法，求得最优解，包括用户对充电站的选择以及是否要寻求优先服务，即x_i,j和b_i,j的取值。若则最优策略是不选择任何充电站。Through the optimization algorithm, the optimal solution is obtained, including the user's choice of charging station and whether to seek priority service, that is, the values of x _i,j and b _i,j . like Then the optimal strategy is not to choose any charging station.

可见，本发明具有以下优点：Visible, the present invention has the following advantages:

1)借助于VANET环境，允许用户通过应用单元130排队取号，节省一定量的时间，即抵达充电站期间内所到达用户的充电时间。在本实施例中，对于VIP用户，节省的时间为对于普通用户，节省的时间为 1) With the help of the VANET environment, users are allowed to queue up to get a number through the application unit 130, saving a certain amount of time, that is, the charging time of the arriving users during the period of arriving at the charging station. In this embodiment, for VIP users, the time saved is For the average user, the time savings is

式中，v_i为电动汽车i的平均车速。In the formula, v _i is the average speed of electric vehicle i.

2)推送提醒服务的设置，使用户无需停留在充电站，对等待充电时间太长的问题上给出了一种有效方案。2) The setting of the push reminder service makes the user not need to stay at the charging station, and provides an effective solution to the problem of waiting too long for charging.

3)允许用户在付出额外附加费用的条件下寻求优先服务。3) Allow users to seek priority services under the condition of paying additional additional fees.

4)考虑地段差异以及需求调整，提出的定价机制使充电价格随着排队情况动态变化，利于调整充电需求，提高电网稳定性。4) Considering location differences and demand adjustments, the proposed pricing mechanism makes the charging price dynamically change with the queuing situation, which is conducive to adjusting the charging demand and improving the stability of the power grid.

Claims

1. The electric vehicle charging scheduling system based on the VANET is characterized by comprising an electric vehicle intelligent electric meter system (100), a road side unit (200), a server (300) and a charging station intelligent electric meter system (400); the electric vehicle intelligent electric meter system (100) comprises an intelligent electric meter (110), a vehicle-mounted GPS positioning device (120), an application unit (130) and a vehicle-mounted unit (140), wherein the charging station intelligent electric meter system (400) comprises an intelligent electric meter (410) and a charging station control management unit (420); the intelligent electric meter (110) and the vehicle-mounted GPS positioning device (120) are respectively in wired connection with the vehicle-mounted unit (140), the application unit (130) is in wired or wireless connection with the vehicle-mounted unit (140), the vehicle-mounted unit (140) and the road side unit (200) are in wireless communication through V2V and V2R respectively, the road side unit (200) is in wired connection with the road side unit (200), the road side unit (200) and the charging station control management unit (420) are respectively in wired connection with the server (300), and the intelligent electric meter (410) is in wired connection with the charging station control management unit (420).

2. The VANET-based electric vehicle charging scheduling system of claim 1, wherein the smart meter (110) in the electric vehicle smart meter system (100) is used for detecting the charge state of a battery, the speed and the charge and discharge amount of an electric vehicle, judging the energy flowing direction according to the phase difference of voltage and current waveforms, calculating the charge and discharge habits of a user according to historical data and user input data, and pushing a charge and discharge suggestion to the user through the application unit (130) when a certain charge state is met and the charge and discharge habits of the user are met; the vehicle-mounted GPS positioning device (120) is used for positioning the position of the electric automobile and providing shortest path navigation to a target charging station; the application unit (130) is a mobile application of a mobile phone or an embedded unit integrated in the vehicle-mounted unit (140), and when an electric vehicle user needs a charging service, the electric vehicle user can directly queue for number fetching through the application unit (130) and has a push service, so that a certain time is saved for the user; the vehicle-mounted unit (140) is mounted on an electric vehicle, and electric vehicle information is relayed and forwarded between the vehicle-mounted units (140) through V2V wireless communication; the roadside units (200) are uniformly deployed at two sides of a road, and electric vehicle information transmitted by the vehicle-mounted unit (140) is collected through V2R wireless communication; the intelligent electric meter (410) in the charging station intelligent electric meter system (400) has the functions of collecting electric power price information of a power grid, detecting the charging amount input to the electric automobile, calculating the real-time queuing condition and formulating the real-time charging price; the function of the charging station control management unit (420) is to transmit real-time charging station information to the server (300), queuing users queued on the application unit (130) and users arriving at the charging station; the server (300) calculates an optimal charging station strategy according to the information transmitted by the road side unit (200) and the charging station control management unit (420); and after receiving the optimal strategy transmitted by the server (300), the road side unit (200) transmits the optimal strategy to the electric automobile user through R2V and V2V wireless communication.

3. The VANET-based electric vehicle charging scheduling system of claim 1 or 2, characterized in that V2V wireless relay forwarding between the vehicle-mounted unit (140) and the vehicle-mounted unit (140) is single hop or multi-hop.

4. The VANET-based electric vehicle charging scheduling system of claim 1 or 2, wherein the real-time charging station information transmitted by the charging station control management unit (420) to the server (300) comprises position information, real-time charging price, queuing condition; the system is also used for pushing reminding information to the user, and comprises a reminding time starting point and a reminding interval time according to the preference and the living habit setting of the user.

5. The VANET-based electric vehicle charging scheduling system of claim 4, wherein the real-time charging price established by the smart meters (410) in the charging station smart meter system (400) relates to the district difference and the demand adjustment.

6. A VANET-based electric vehicle charging scheduling method is characterized by comprising the following steps:

s100, the intelligent electric meters (410) of all charging stations are combined with the positions of the places where the intelligent electric meters are located and the electric power price information, real-time charging prices are formulated according to the current queuing conditions, and the charging station control management unit (420) transmits the real-time charging station information to the server (300);

s200, when the intelligent electric meter (110) in the electric automobile intelligent electric meter system (100) detects that the charge state of a battery is lower than a certain threshold value or accords with the charging habit of a user, the vehicle-mounted unit (140) sends a charging service demand and electric automobile real-time information to the server (300);

s300, calculating by the server (300) according to the received real-time information of the electric automobile and the charging station to obtain an optimal charging station strategy and a function utility value of the electric automobile;

s400, the vehicle-mounted unit (140) pushes the received optimal charging station strategy, the function utility value and the charging station information to a user through the application unit (130);

s500, selecting whether to charge or not by a user according to the self requirement and the judgment on the function utility value, and directly queuing and taking a number on a target charging station interface through an application unit (130) if the charging selection is confirmed;

s600, after receiving queuing information transmitted by the application unit (130), a charging station control management unit (420) of the target charging station arranges a user into a charging queue;

s700, when a user wants to go to a target charging station, the application unit (130) sends a decision to the vehicle-mounted GPS positioning device (120), and the vehicle-mounted GPS positioning device (120) provides shortest path navigation to the target charging station.

7. The VANET-based electric vehicle charging scheduling method according to claim 6, characterized in that after the step S600, the method further comprises the step S600A: judging whether the user needs to push the reminding service, if so, sending push information to the application unit (130) at a specific time according to the user setting; otherwise, step S700 is performed.

8. The VANET-based electric vehicle charging scheduling method according to claim 6, wherein the specific steps of the step S100 are as follows:

s110, calculating average queuing waiting time, and averaging the queuing waiting length;

s120, setting the regional price f by the charging station j according to the district_j ^（1 ^）Adjusting the price f according to the demand calculated by the queuing condition_j ^（2 ^）Weighted to obtain the charge price f_j；

S130, transmitting real-time charging station information including charging price, additional cost, position information and queuing condition to the server (300).

9. The VANET-based electric vehicle charging scheduling method according to claim 6, wherein the specific steps of the step S300 are as follows:

s310, determining each weight of the utility function and a user parameter value according to the user characteristics;

s320, calculating utility values of the charging stations to users according to the electric vehicles and the real-time information of the charging stations to obtain a target function;

and S330, optimizing the objective function to obtain an optimal charging station selection strategy.