Charging system of electric vehicle

Abstract

To provide a charging system more promptly executing charging of a BEV in a charging system which can charge a plurality of electric vehicles concurrently.SOLUTION: In a charging system 1, when a battery type electric vehicle (BEV) and a plug-in hybrid vehicle (PHEV) are respectively connected to power transmission / reception means (voltage / current regulators 7a-7d, power lines 8a-8d, and a connection plug 9) which can charge / discharge power of the system, a system controller 10 controlling transmission of power in power transmission means 6 connected to each of a power system GP and the power transmission / reception means and transmitting power between them controls a state of the power transmission means so that power generated by making the PHEV execute power generation may be charged to the BEV through the power transmission means from the power transmission / reception means to which the PHEV is connected through the connected power transmission / reception means when a predetermined condition is satisfied.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a charging system for electric vehicles, and more particularly to a charging system capable of charging a plurality of electric vehicles at one time.

Background Art

[0002] With the popularization of electric vehicles, various configurations for equipment for charging electric vehicles have been proposed. For example, in Patent Document 1, in a charging control device capable of charging power storage devices mounted on a plurality of vehicles with an external power source, in order to suppress deterioration of the power storage devices of each vehicle, the charging state values of the respective power storage devices converge within an allowable range. It has been proposed to transfer power between a plurality of vehicles so that this occurs. In Patent Document 2, when a virtual power plant using a plurality of electric vehicles as energy resources is used for adjusting the power supply and demand balance, in order to be able to flexibly respond to unplanned adjustments, when a power adjustment request is received, based on the behavior of the electric vehicle predicted from the vehicle information, an electric vehicle charge / discharge plan created to meet the power adjustment request is instructed to the electric vehicle, and when an additional request regarding power adjustment is received after the instruction of the charge / discharge plan, a change charge / discharge plan including information regarding economic merits created to meet the additional request based on the predicted behavior of the electric vehicle is presented to the electric vehicle. Patent Document 3 proposes dividing electric vehicles into a plurality of groups according to predetermined characteristics based on the vehicle information of a plurality of electric vehicles connected to the power grid in order to optimize the sharing of power demand for electric vehicles, and adjusting the charge / discharge burden of electric vehicles for each group when adjusting the power demand of the power grid.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0004] With the spread of externally rechargeable electric vehicles (battery electric vehicles (BEVs), plug-in hybrid cars (PHEVs)), a charging system (such as a rapid charger) capable of charging multiple electric vehicles simultaneously has been put into practical use. However, on the other hand, with the increase in the number of BEVs and PHEVs, situations where multiple electric vehicles require charging simultaneously occur frequently, and there may be charging congestion where multiple electric vehicles wait to be charged at charging facilities. By the way, among externally rechargeable electric vehicles, in the case of PHEVs, since electricity can be generated by the engine, when a PHEV and a BEV are simultaneously connected to the charging system, depending on the conditions, if the PHEV can generate electricity and the electricity can be charged to the BEV via the charging system, the charging of the BEV will proceed more quickly and contribute to the elimination of charging congestion.

[0005] Thus, the main problem of the present invention is to enable the charging of a BEV to be executed more quickly in a charging system capable of charging multiple electric vehicles simultaneously.

Means for Solving the Problems

[0006] According to the present invention, the above problem is a charging system capable of charging multiple electric vehicles simultaneously, a plurality of power transmission and reception means, each including a power transmission and reception means connected to an electric vehicle and capable of charging and discharging power between the electric vehicle and the electric vehicle, a power transmission means connected to each of the power system and the power transmission and reception means and transmitting power between the power system and the power transmission and reception means and between the power transmission and reception means, and a power transmission control means for controlling the transmission of power in the power transmission means. When at least one BEV and at least one PHEV are connected to any of the power transmission and reception means, when a predetermined condition is satisfied, the power transmission control means causes any one of the at least one PHEV to generate power, and the power generated by the PHEV is transmitted from the power transmission and reception means to which the PHEV is connected through the power transmission means to any one of the at least one BEV. This is achieved by a charging system configured to control the state of the power transmission means so as to charge through the power transmission and reception means to which it is connected.

[0007] In the above configuration, the "electric vehicle" includes BEVs and PHEVs that can be charged from the outside. The "charging system" targeted by the present invention is a system that can charge a plurality of electric vehicles simultaneously as described above, and has a plurality of power transmission and reception means that may be power lines and power supply plugs connected to the electric vehicle and performing power transmission and reception with the electric vehicle, and a power transmission means for transmitting power between the power transmission and reception means and the power grid and between the power transmission and reception means is provided. It is a system configured such that power transmission between the power transmission and reception means and the power grid and between the power transmission and reception means in the power transmission means can be appropriately controlled. Specifically, it may be a rapid charger having a plurality of power supply plugs.

[0008] In such a configuration, in the case of the present invention, as described above, when at least one BEV and at least one PHEV are connected to the charging system, when a predetermined condition set as appropriate is satisfied, the state of the power transmission means is controlled so that at least one PHEV generates power and the power is charged to at least one BEV. According to such a configuration, it is expected that the charging of the BEV is executed more quickly and the charging cycle in the system becomes shorter.

[0009] In the above configuration of the present invention, the process of causing the PHEV to generate power and charging the power to the BEV may be executed, for example, when any of the following conditions is satisfied. (1) When the state of charge (SOC) of the battery of a PHEV reaches the required SOC and the user of the PHEV permits the transfer of power to a BEV (charging the BEV). - The required SOC may be determined by any method based on the driving history of the PHEV or the input content to the navigation device, etc. (2) When the user of the BEV requests the transfer of power from the PHEV to the BEV and the user of the PHEV permits the transfer of power. Therefore, the power transmission control means of the charging system of the present invention has means for detecting the SOC of the PHEV and BEV connected to the system, means for determining or calculating the required SOC by any method based on the driving history of the PHEV and BEV or the input content to the navigation device, etc., and means for obtaining and processing the requests and permissions from the PHEV and BEV. According to the processing of these means, it may be configured to appropriately execute the process of generating power in the PHEV and charging the BEV with that power.

[0010] Also, in the configuration of the present invention described above, as reference information for the user to determine whether to permit or execute the transfer of power from the PHEV to the BEV, information providing means may be provided to provide the user with comparison information between the price of fuel (gasoline, light oil) at a fuel supply stand near the charging system and the price of the transfer of power to the BEV (selling electricity price). More specifically, the selling electricity price for an arbitrary amount of power from the PHEV to the BEV and the amount obtained by multiplying the amount of fuel required to generate that amount of power in the PHEV by the price per unit amount of fuel are presented to the user. The user refers to these amounts to determine whether to permit or request the transfer of power from the PHEV to the BEV, and the system may be provided with the necessary means so that the determination is input to the system. Note that the selling electricity price for an arbitrary amount of power from the PHEV to the BEV may be determined in any manner, and may be appropriately determined based on the selling electricity price per unit amount of power when charging from the power grid, the actual cost required to generate a unit amount of power in the PHEV, etc.

[0011] In the charging system according to the present invention described above, when a plurality of electric vehicles are connected to the power transmission and reception means and are in a chargeable state, based on the future action plan data and SOC information of each electric vehicle, the degree of necessity of charging for each vehicle is determined, and means for preferentially increasing the power transmission amount in descending order of the degree of necessity may be provided.

Effect of the Invention

[0012] Thus, according to the configuration of the present invention, as described above, in a charging system capable of simultaneously charging a plurality of electric vehicles, when at least one PHEV and at least one BEV are connected, under predetermined conditions, the power generated by the PHEV is configured to be charged to the BEV. According to such a configuration, the charging of the BEV can be executed more quickly, and the charging cycle in the system becomes shorter. Therefore, this configuration is expected to help solve the charging congestion.

[0013] Other objects and advantages of the present invention will become apparent from the following description of the preferred embodiments of the present invention.

Brief Description of the Drawings

[0014]

Figure 1

Description of the Reference Numerals

[0015] 1... Charging system (rapid charger), 2a, 2b, 2c... Vehicles, 3a, 3b, 3c... On-vehicle communication devices, 4... Power line, 5... Voltage and current regulator, 6... Power line, 7a, 7b, 7c, 7d... Voltage and current regulators, 8a, 8b, 8c, 8d... Power lines, 9... Connection plug, 10... System controller, GP... Power grid

Best Mode for Carrying Out the Invention

[0016] The present invention will be described in detail below with reference to the accompanying drawings in several preferred embodiments. In the drawings, the same reference numerals indicate the same parts.

[0017] Configuration of Charging System Referring to FIG. 1, the charging system 1 according to the present embodiment may basically be a system such as a so-called "rapid charger" that can simultaneously supply power from the power grid GP to a plurality of electric vehicles 2a to 2c. The electric vehicles 2a to 2c may be BEVs, PHEVs, etc. that can be charged from the outside. In such a charging system 1, more specifically, the power drawn from the power grid GP by the power line 4 is transmitted to the power line 6 while the voltage or current is adjusted by the voltage / current regulator 5, and from there, it is distributed to the power lines 8a to 8d connected to each of the plurality of electric vehicles 2a to 2c via the connection plugs 9. Here, the power distributed to the power lines 8a to 8d for distributing power to each electric vehicle has its voltage and current controlled by the voltage / current regulators 7a, 7b, 7c, 7d provided in each of the power lines 8a to 8d. Also, the operations of the voltage / current regulator 5, the voltage / current regulators 7a, 7b, 7c, and 7d are controlled by the system controller 10 in various modes to be described later. At this time, in the present embodiment, the system controller 10 communicates with the electric vehicles 2a to 2c by communication means that may be in a wireless format, acquires various information (SOC, past driving history, planned future driving distance, user's will, etc.) from the electric vehicles 2a to 2c, and further communicates with an external network NW to acquire information from surrounding fuel stations. Based on this information, the power and the amount of power supplied to each electric vehicle are adjusted, or power generation is performed on the PHEV, and the power obtained there is transmitted to another electric vehicle. The operations of the voltage / current regulators 7a, 7b, 7c, and 7d are configured to be controlled.

[0018] Operation of Charging System (1) Charging of Electric Vehicles with Power from the Power Grid GP In the charging system 1 according to this embodiment, basically, the charging and discharging port of the electric vehicle is connected to any one of the connection plugs 9 of the power lines 8a to 8d, and in a normal mode, the power from the power grid GP is adjusted in terms of voltage and current, and charging of the electric vehicle may be executed. In such a system, in the conventional case, the power from the power grid GP is evenly distributed and transmitted to the electric vehicles connected to the system (that is, when the number of connected electric vehicles is two, the power temporarily supplied from the system is distributed to each electric vehicle by 50% and transmitted). However, in this regard, among a plurality of electric vehicles connected to the system, the degree of necessity for quickly charging the power may be different from each other. In that case, for the electric vehicle with a higher degree, it is advantageous that the supply power is relatively increased compared to others and charging can be preferentially executed. Therefore, in this embodiment, as one aspect, the system controller 10 acquires information such as the SOC, past driving history, and planned future driving distance of each electric vehicle connected to the system, and based on the acquired information, determines the degree of necessity for charging each electric vehicle, and controls the states of the voltage / current regulators 7a, 7b, 7c... so that the supply power increases as the determined degree of necessity for charging each electric vehicle is higher.

[0019] The degree of necessity for charging each electric vehicle may be determined as follows. (a) For an electric vehicle in which the amount of power sufficient to travel the planned future driving distance (determined from the input state of the navigation device) is charged, the degree of necessity for charging is reduced. (b) For an electric vehicle in which the SOC has reached the necessary SOC appropriately determined from information such as the past driving history and the planned future driving distance, the degree of necessity for charging is reduced. - The necessary SOC may be the SOC that can achieve the driving of the distance planned in the future from information such as the past driving history and the planned future driving distance, rather than a full charge. (c) Since the PFEV can travel by an engine, when the SOC has reached the necessary SOC, the degree of necessity for charging is reduced compared to the BEV. Note that the degree of charging necessity may be calculated by any method or calculation formula as a priority with a higher value as the degree increases. Corresponding to the ratio of priorities, the ratio of the power supplied to the electric vehicle in the total power supplied from the system may be determined. For example, when the priority of a certain vehicle i is Ai, the power Pi supplied to the vehicle may be Pi = PT × Ai / ΣAi determined by this formula. Here, PT is the total power supplied from the system, and ΣAi is the sum of the priorities of the electric vehicles connected to the system.

[0020] (2) Charging from PHEV to BEV In the charging system 1 according to this embodiment, when at least one PHEV and at least one BEV are simultaneously connected to the system 1, when a predetermined condition as exemplified below is satisfied, the system controller 10 may be configured to control the voltage / current regulators 7a to 7d so as to cause the PHEV to execute power generation and transmit the power to the BEV using the power lines 8a to 8d and the power line 6. Specifically, power transmission from the PHEV to the BEV may be executed when any of the following conditions is satisfied. (a) When the SOC of the battery of the PHEV reaches the required SOC (b) When the user of the BEV requests earlier completion of charging In any case, charging of the power generated by the PHEV to the BEV may be limited only when the user of the PHEV permits the transfer of power to the BEV (charging the BEV).

[0021] Regarding this point, in order to facilitate the determination of whether a PHEV user permits charging of a BEV or whether a BEV user requests earlier completion of charging, information regarding the cost required for charging a BEV with the electric power generated by a PHEV may be provided to the users of electric vehicles. Specifically, by referring to the prices of fuels (gasoline, light oil) at a fuel supply stand near the charging system, the amount obtained by multiplying the amount of fuel required to generate an arbitrary amount of electric power in a PHEV by the price per unit amount of fuel and the selling electricity price when transmitting that arbitrary amount of electric power from the PHEV to the BEV are presented. As a result, it is expected that each user can easily determine whether to permit or request charging of a BEV with the electric power generated by a PHEV by referring to these amounts and prices. The system controller 10 may be provided with facilities such as communication devices required to obtain the above series of information. Also, the will of each user may be transmitted to the system controller 10 using the communication devices provided in each vehicle or using each user's portable terminal (smartphone, tablet, etc.), and facilities for that purpose may be prepared in each vehicle. The selling electricity price for the electric power from the PHEV to the BEV may be arbitrarily determined, and may be appropriately set based on the fuel price, the amount permitted by the PHEV user, and the price (premium price) permitted by the BEV user so that the PHEV user does not suffer losses. According to such a configuration, if the cost required to generate a certain amount of electric power using fuel in a PHEV is lower than the cost when transferring that amount of electric power to a BEV, it is expected that it will be easier for the PHEV user to decide to generate electric power using fuel in the PHEV and transfer the electric power there to the BEV.

[0022] Thus, according to this embodiment, when a PHEV and a BEV are connected to the charging system 1, when the above-described predetermined conditions are satisfied, the PHEV is made to execute power generation, and the electric power generated there is used to charge the BEV, or the priority indicating the degree of necessity of charging is determined for each of a plurality of electric vehicles connected to the charging system 1, and by increasing the magnitude of the supplied power in correspondence with the increase in that priority, the time required for charging each vehicle is made efficient, and an attempt is made to eliminate charging congestion.

[0023] The above description has been made in relation to embodiments of the present invention, but many modifications and changes are easily possible for those skilled in the art, and it is obvious that the present invention is not limited only to the embodiments illustrated above and can be applied to various devices without departing from the concept of the present invention.

Claims

【Claim 1】 A charging system capable of simultaneously charging a plurality of electric vehicles, comprising a plurality of power transmission and reception means, each of which is connected to an electric vehicle and capable of charging and discharging power between the electric vehicle; power transmission means connected to each of the power grid and the power transmission and reception means for transmitting power between the power grid and the power transmission and reception means and between the power transmission and reception means; and power transmission control means for controlling the power transmission in the power transmission means. When at least one BEV and at least one PHEV are connected to any of the power transmission and reception means, the power transmission control means causes any one of the at least one PHEV to generate power when a predetermined condition is satisfied, and charges the power generated by the PHEV from the power transmission and reception means to which the PHEV is connected through the power transmission means to any one of the at least one BEV through the power transmission and reception means to which it is connected. A charging system configured to control the state of the power transmission means.

Images