JP7572892B2 - Charging System - Google Patents

Description

The present invention relates to a charging system for charging an on-board battery.

For example, Patent Document 1 discloses an example of a technology for charging an on-board battery using power supplied to the vehicle from outside the vehicle.

Patent No. 5493510

Power supply areas where charging stations are installed can become congested with vehicles waiting to charge. Therefore, it is possible to predict waiting times based on the number of charging stations installed in a power supply area. However, there are two types of charging stations: AC stations that supply alternating current power to vehicles, and DC stations that supply direct current power to vehicles. In contrast, vehicles may be capable of using both AC and DC stations. For this reason, if congestion is predicted simply based on the number of charging stations, there is a risk that the actual waiting time will deviate from the predicted waiting time depending on which charging method is used.

Therefore, the present invention aims to provide a charging system that can grasp the potential demand for charging for each charging method.

In order to solve the above problem, the charging system of the present invention includes a charging execution unit capable of executing at least one of AC charging, which charges an on-board battery based on AC power supplied from outside the vehicle, and DC charging, which charges an on-board battery based on DC power supplied from outside the vehicle, an on-board memory unit that stores charging history data indicating the charging history of AC charging and DC charging, an expected value derivation unit that derives, for each vehicle within a specified power supply area, an AC charging execution expected value indicating the expected value at which AC charging will be performed and a DC charging execution expected value indicating the expected value at which DC charging will be performed based on the charging history data, and a charging time when the vehicle performs AC charging. The system includes a charging prediction time derivation unit that derives an AC charging prediction time indicating a predicted value between the start of AC charging and the start of charging when the vehicle performs DC charging based on the DC charging execution expected value, and a congestion prediction time derivation unit that derives an AC congestion prediction time indicating a predicted value of the waiting time until AC charging starts for a specific vehicle based on the AC charging prediction time for target vehicles other than the specific vehicle among candidate vehicles present in the power supply area, and derives a DC congestion prediction time indicating a predicted value of the waiting time until DC charging starts for the specific vehicle based on the DC charging prediction time for the target vehicles.

The charging history data is set in advance into a number of categories that divide the possible range of the battery remaining amount at the start of charging, and each of the categories is associated with a predetermined category corresponding to the battery remaining amount at the start of charging for each charge, an AC charging count indicating the number of times AC charging was started with the battery remaining amount within the predetermined category, and a DC charging count indicating the number of times DC charging was started with the battery remaining amount within the predetermined category. The expected value derivation unit may derive the AC charging execution expected value by dividing the AC charging count in the predetermined category corresponding to the current battery remaining amount by the total charging count which is the sum of the AC charging counts in all categories and the DC charging counts in all categories, and derive the DC charging execution expected value by dividing the DC charging count in the predetermined category corresponding to the current battery remaining amount by the total charging count.

The congestion prediction time derivation unit may also derive an AC congestion prediction time if the number of AC charges is greater than the number of DC charges in a specified section corresponding to the current remaining battery charge, and derive a DC congestion prediction time if the number of DC charges is greater than the number of AC charges.

The predicted charging time derivation unit may also derive the predicted AC charging time based on the amount of chargeable energy indicating the reduction in charging capacity from the full charge capacity of the vehicle battery, the total AC possible charging output indicating the total amount of power that can be supplied by AC stands used for AC charging within the power supply area, and the expected value for AC charging execution, and derive the predicted DC charging time based on the amount of chargeable energy, the total DC possible charging output indicating the total amount of power that can be supplied by DC stands used for DC charging within the power supply area, and the expected value for DC charging execution.

The present invention makes it possible to grasp the potential demand for charging for each charging method.

FIG. 1 is a schematic diagram showing the configuration of a charging system according to this embodiment. FIG. 2 is a diagram illustrating an example of the charging history data. 3A and 3B are diagrams showing examples of a management list, in which Fig. 3A shows an example of a station management list, and Fig. 3B shows an example of a vehicle management list. FIG. 4 is a flowchart illustrating the relationship between the operation flow of the power supply facility and the operation flow of the server device. FIG. 5 is a flowchart illustrating the relationship between the flow of periodic vehicle operations and the flow of server device operations. FIG. 6 is a flowchart illustrating the flow of operations of the congestion predicted time derivation unit. FIG. 7 is a flowchart illustrating a modified example of the operation of the congestion predicted time derivation unit.

The following describes in detail an embodiment of the present invention with reference to the attached drawings. The dimensions, materials, and other specific values shown in the embodiment are merely examples to facilitate understanding of the invention, and do not limit the present invention unless otherwise specified. In this specification and drawings, elements that have substantially the same function and configuration are given the same reference numerals to avoid duplicated explanations, and elements that are not directly related to the present invention are not illustrated.

Figure 1 is a schematic diagram showing the configuration of a charging system 1 according to this embodiment. The charging system 1 includes a plurality of vehicles 12 to which charging devices 10 are applied, a power supply facility 14, and a server device 16.

For ease of explanation, seven vehicles 12A, 12B, 12C, 12D, 12E, 12F, and 12G are shown in FIG. 1 as an example of vehicles 12. There may be any number of vehicles 12, and the number is not limited to seven, and may be any number.

The vehicle 12 is, for example, an electric vehicle or a hybrid vehicle. The vehicle 12 is provided with an on-board battery 20. The on-board battery 20 supplies power to a motor (not shown) that is the drive source of the vehicle 12. The charging device 10, which will be described in detail later, can be electrically connected to a power supply facility 14, and charges the on-board battery 20 with power supplied from the power supply facility 14. In other words, the charging device 10 can perform so-called plug-in charging.

The power supply facility 14 is provided with one or more charging stands 30. In the example of FIG. 1, the power supply facility 14 is provided with three charging stands 30. The number of charging stands 30 is not limited to three, and may be any number according to the size or location of the power supply facility 14. The charging stand 30 is connected to a power supply source (not shown). The power supply source is, for example, a commercial power system. A charging connector 32 is connected to the charging stand 30 via a cable. As will be described in detail later, the charging stand 30 converts the power of the power supply source and supplies it to the vehicle 12 via the charging connector 32.

There are two types of charging stands 30: AC stands 30A and DC stands 30D. In the example of FIG. 1, of the three charging stands 30, one is an AC stand 30A and the other two are DC stands 30D. The AC stand 30A supplies AC power to the vehicle 12. The DC stand 30D supplies DC power to the vehicle 12. The charging connector 32 of the AC stand 30A and the charging connector 32 of the DC stand 30D differ in the terminal arrangement or socket shape at the end.

The equipment control unit 34 is a computer composed of semiconductor integrated circuits including a central processing unit, a ROM in which programs and the like are stored, and a RAM as a work area. The equipment control unit 34 cooperates with the program to control the entire power supply equipment 14.

The equipment control unit 34 can communicate with the charging device 10 of the vehicle 12 through the charging connector 32. When instructed to start charging, the equipment control unit 34 causes the charging stand 30 to start supplying power to the vehicle 12, and when instructed to end charging, causes the charging stand 30 to end supplying power to the vehicle 12.

The equipment communication unit 36 is connected to a communication network such as the Internet. The equipment control unit 34 can communicate with the server device 16 through the equipment communication unit 36. The equipment control unit 34 transmits equipment information about the power supply equipment 14 to the server device 16 through the equipment communication unit 36.

The facility information includes a station identifier that uniquely identifies the charging station 30, the charging method of the charging station 30, and the possible charging output of the charging station 30. The charging method of the charging station 30 indicates whether it is an AC station 30A or a DC station 30D. The possible charging output of the charging station 30 indicates the amount of power that the charging station 30 can supply, in other words, the maximum output.

The equipment control unit 34 also periodically transmits a vehicle identifier that uniquely identifies the vehicle 12 being charged to the server device 16 via the equipment communication unit 36.

The charging device 10 includes a charging inlet 40, a charging unit 42, a vehicle memory unit 44, a vehicle communication unit 46, and a charging control unit 48. The charging inlet 40 is provided, for example, on the side of the body of the vehicle 12. The charging inlet 40 includes an inlet housing formed in a hollow box shape, and a charging lid that is provided so as to be able to open and close the opening on the front side of the inlet housing.

The inlet housing contains an AC charging port 50A and a DC charging port 50D. When the charging lid is opened, the AC charging port 50A and the DC charging port 50D are exposed to the outside of the vehicle. The AC charging port 50A can be connected to the charging connector 32 of the AC stand 30A. The DC charging port 50D can be connected to the charging connector 32 of the DC stand 30D. Hereinafter, the AC charging port 50A and the DC charging port 50D may be collectively referred to simply as the charging port.

The AC charging port 50A and the DC charging port 50D are electrically connected to the vehicle battery 20 through the charging unit 42. In other words, the same vehicle battery 20 can be charged using either the AC charging port 50A or the DC charging port 50D. The charging unit 42 includes a switch that turns on and off the electrical connection between the AC charging port 50A and the DC charging port 50D and the vehicle battery 20. The charging unit 42 also includes a current measuring unit that measures the charging current flowing through the vehicle battery 20. The charging unit 42 also includes a voltage measuring unit that measures the voltage of the vehicle battery 20. When the charging unit 42 receives AC power through the AC charging port 50A, it converts it into DC power and supplies it to the vehicle battery 20.

The charging device 10 can perform AC charging by connecting the charging connector 32 of the AC stand 30A to the AC charging port 50A and charging the vehicle battery 20 based on the AC power supplied from the AC stand 30A. The charging device 10 can also perform DC charging by connecting the charging connector 32 of the DC stand 30D to the DC charging port 50D and charging the vehicle battery 20 based on the DC power supplied from the DC stand 30D.

The charging device 10 is not limited to being capable of both AC charging and DC charging, but may be capable of at least one of AC charging and DC charging. In other words, the charging device 10 may be provided with at least one of the AC charging port 50A and the DC charging port 50D, and the other of the AC charging port 50A and the DC charging port 50D may be omitted.

In a vehicle 12 that is equipped with both an AC charging port 50A and a DC charging port 50D, the user of the vehicle 12 can choose whether to perform AC charging or DC charging.

The vehicle memory unit 44 is an on-board memory unit and is composed of a non-volatile memory element. The vehicle memory unit 44 stores charging history data 52. The charging history data 52 indicates the charging history of AC charging and DC charging that have been performed in the vehicle in the past. The charging history data 52 is updated each time charging is performed.

Figure 2 is a diagram showing an example of charging history data 52. Note that the values shown in Figure 2 are merely examples, and the specific values are not limited to those shown in Figure 2.

In the charging history data 52, a number of categories are set in advance, which are obtained by dividing the possible range of the remaining battery charge at the start of charging into a number of categories. The remaining battery charge is specifically the SOC (State Of Charge) of the in-vehicle battery 20. For example, category "1" corresponds to the case where the SOC at the start of charging is in the range of 0% or more and 10% or less. Category "2" corresponds to the case where the SOC at the start of charging is in the range of more than 10% and 20% or less. Category "3" corresponds to the case where the SOC at the start of charging is in the range of more than 20% and 30% or less. Although not described below, in the charging history data 52, categories are set in a similar manner every 10%, and 10 categories from category "1" to "10" are set. Note that the number of categories is not limited to 10 and may be set arbitrarily.

As illustrated in FIG. 2, the charging history data 52 is associated with a predetermined category, the number of AC charges corresponding to the predetermined category, the number of DC charges corresponding to the predetermined category, and a subtotal obtained by adding up the number of AC charges and the number of DC charges for each of the multiple categories. The predetermined category here is a category corresponding to the remaining battery capacity at the start of charging for each charge. For example, category "3" corresponds to the case where charging is started in a state where the SOC is greater than 20% and is less than or equal to 30%. The number of AC charges corresponding to the predetermined category indicates the number of times AC charging was started with the remaining battery capacity of the predetermined category. For example, the number of AC charges corresponding to category "3" indicates the number of times AC charging was started with the SOC being greater than 20% and is less than or equal to 30%. The number of DC charges corresponding to the predetermined category indicates the number of times DC charging was started with the remaining battery capacity of the predetermined category. For example, the number of DC charges corresponding to category "3" indicates the number of times DC charging was started with the remaining battery capacity of the predetermined category. The subtotal indicates the number of times charging was started with a specified battery level regardless of whether AC or DC charging was used.

For example, in category "3," where the SOC is greater than 20% and is within the range of 30% or less, the number of AC charges is "18," and the number of DC charges is "40." This indicates that when charging is started in category "3," DC charging is selected more often than AC charging. In other words, charging history data 52 indicates, for each of multiple categories, whether AC charging or DC charging is more likely to be performed. Furthermore, charging history data 52 indicates the remaining battery charge level at which AC charging or DC charging is more likely to be performed.

The charging history data 52 also includes the total number of charges, which is the sum of the number of AC charges in all categories and the number of DC charges in all categories.

The charging history data 52 is not limited to being classified by the SOC of the in-vehicle battery 20, but may be classified by the amount of chargeable energy, which is another specific example of the remaining battery capacity. The amount of chargeable energy is the value obtained by subtracting the charging capacity corresponding to the SOC from the full charging capacity, and indicates the reduction in charging capacity from the full charging capacity.

Returning to FIG. 1, the vehicle communication unit 46 establishes communication with the server device 16, for example, by wireless communication. The vehicle communication unit 46 may also establish vehicle-to-vehicle communication with other vehicles.

The charging control unit 48 is a computer composed of semiconductor integrated circuits including a central processing unit, a ROM in which programs and the like are stored, and a RAM as a work area. The charging control unit 48 cooperates with the program to control the charging of the vehicle battery 20. By executing the program, the charging control unit 48 functions as a charging execution unit 60, an expected value derivation unit 62, a predicted charging time derivation unit 64, and a predicted congestion time derivation unit 66.

The charging execution unit 60 performs AC charging when the charging connector 32 is connected to the AC charging port 50A, and performs DC charging when the charging connector 32 is connected to the DC charging port 50D. For example, the charging execution unit 60 instructs the equipment control unit 34 via the charging connector 32 to start and end AC charging or DC charging.

Here, a specific area including the location where the power supply equipment 14 is installed is called a power supply area 70. The power supply area 70 is an area whose outer edge can be identified, such as a service area or a parking area. The power supply area 70 is divided for each power supply equipment 14, and may be provided in multiple locations. In the example of FIG. 1, one power supply area 70 is illustrated for ease of explanation.

In the example of FIG. 1, it is assumed that vehicle 12E is being charged at AC station 30A, and vehicles 12F and 12G are being charged at DC station 30D. It is also assumed that vehicles 12A, 12B, and 12C are within power supply area 70, and vehicle 12D is outside power supply area 70. Hereinafter, vehicles 12 (e.g., vehicles 12A, 12B, and 12C) that are within a specific power supply area 70 and are not being charged may be referred to as candidate vehicles. Candidate vehicles refer to vehicles that may be charging within power supply area 70. Note that candidate vehicles are not limited to vehicles waiting to be charged, and may include vehicles that are not being charged.

Since all charging stations 30 in the power supply area 70 are in use, vehicles 12A, 12B, and 12C may be waiting to be charged. In the charging system 1, it is possible to predict the waiting time until charging begins for the vehicles waiting to be charged. In this case, the charging system 1 predicts the waiting time for AC charging and the waiting time for DC charging separately. The function that realizes this is described below.

The expected value derivation unit 62 derives an AC charging execution expected value and a DC charging execution expected value for the vehicle based on the charging history data 52 for the vehicle within a specified power supply area 70. The AC charging execution expected value indicates the expected value at which AC charging will be performed. The DC charging execution expected value indicates the expected value at which DC charging will be performed.

If the host vehicle is configured to be capable of only AC charging, the expected value derivation unit 62 may derive the AC charging execution expected value and omit the derivation of the DC charging execution expected value. If the host vehicle is configured to be capable of only DC charging, the expected value derivation unit 62 may derive the DC charging execution expected value and omit the derivation of the AC charging execution expected value. The expected value derivation unit 62 will be described in detail later.

The predicted charging time derivation unit 64 derives a predicted AC charging time for the vehicle based on the expected value for AC charging execution for the vehicle. The predicted AC charging time indicates a predicted value of the charging time when the vehicle performs AC charging. The predicted charging time derivation unit 64 also derives a predicted DC charging time for the vehicle based on the expected value for DC charging execution for the vehicle. The predicted DC charging time indicates a predicted value of the charging time when the vehicle performs DC charging.

If the vehicle is configured to be capable of only AC charging, the predicted charging time derivation unit 64 may derive the predicted AC charging time and omit the derivation of the predicted DC charging time. If the vehicle is configured to be capable of only DC charging, the predicted charging time derivation unit 64 may derive the predicted DC charging time and omit the derivation of the predicted AC charging time.

The predicted charging time derivation unit 64 periodically derives the predicted AC charging time and predicted DC charging time within a specified power supply area 70, and transmits the derivation results to the server device 16 via the vehicle communication unit 46.

In the charging system 1, the predicted AC charging time and the predicted DC charging time are derived for each candidate vehicle (vehicle 12A, vehicle 12B, and vehicle 12C) within a specified power supply area 70. Then, in the charging system 1, the predicted AC charging time and the predicted DC charging time for each candidate vehicle are aggregated in the server device 16. The predicted charging time derivation unit 64 will be described in detail later.

Here, the vehicle for which congestion prediction is performed may be referred to as a specific vehicle. The specific vehicle congestion prediction time derivation unit 66 acquires from the server device 16 the AC charging prediction time and the DC charging prediction time of target vehicles excluding the specific vehicle (own vehicle) among the candidate vehicles in the specified power supply area 70. The congestion prediction time derivation unit 66 derives the AC congestion prediction time of the own vehicle based on the acquired AC charging prediction time of the target vehicle. The AC congestion prediction time indicates a predicted value of the waiting time until the start of AC charging. In addition, the congestion prediction time derivation unit 66 derives the DC congestion prediction time of the own vehicle based on the acquired DC charging prediction time of the target vehicle. The DC congestion prediction time indicates a predicted value of the waiting time until the start of DC charging.

For example, the congestion predicted time derivation unit 66 of vehicle 12A derives the AC congestion predicted time of vehicle 12A based on the AC charging predicted time of vehicle 12B and the AC charging predicted time of vehicle 12C. In addition, the congestion predicted time derivation unit 66 of vehicle 12A derives the DC congestion predicted time of vehicle 12A based on the DC charging predicted time of vehicle 12B and the DC congestion predicted time of vehicle 12C.

In addition, the charging system 1 can derive the predicted AC congestion time and predicted DC congestion time even for a vehicle 12D outside the power supply area 70, assuming that charging is performed in the power supply area 70. In this case, the power supply area 70 selected is the power supply area 70 closest to the driving route of the vehicle 12D.

For example, the congestion predicted time derivation unit 66 of vehicle 12D derives the AC congestion predicted time of vehicle 12D based on the AC charging predicted time of each of the target vehicles (vehicle 12A, vehicle 12B, and vehicle 12C) in the specified power supply area 70. In addition, the congestion predicted time derivation unit 66 of vehicle 12D derives the DC congestion predicted time of vehicle 12D based on the DC charging predicted time of each of the target vehicles (vehicle 12A, vehicle 12B, and vehicle 12C) in the specified power supply area 70. The congestion predicted time derivation unit 66 will be described in detail later.

The server device 16 includes a server communication unit 80, a server control unit 82, and a server storage unit 84. The server communication unit 80 establishes communication with the power supply equipment 14 and each vehicle 12.

The server control unit 82 is a computer composed of semiconductor integrated circuits including a central processing unit, a ROM in which programs and the like are stored, and a RAM as a work area. The server control unit 82 works in cooperation with the programs to control the entire server device 16.

The server control unit 82 can receive the equipment information and the vehicle identifier being charged transmitted from the power supply equipment 14 through the server communication unit 80. The server control unit 82 can also receive the AC charging predicted time and the DC charging predicted time transmitted from each vehicle 12 through the server communication unit 80.

The server memory unit 84 is composed of a non-volatile memory element. The server memory unit 84 stores a management list 86 that manages the entire charging system 1. The management list 86 includes a station management list that manages the charging station 30, and a vehicle management list that manages the vehicle 12 to which the charging device 10 is applied.

Figure 3 shows an example of a management list 86. Figure 3A shows an example of a station management list. Figure 3B shows an example of a vehicle management list. Note that the numerical values shown in Figures 3A and 3B are merely examples, and the specific numerical values are not limited to those shown in Figures 3A and 3B.

As shown in FIG. 3A, the station management list registers the station identifier, charging method, and available charging output amount obtained from the facility information in association with each other. The station identifier is also associated with an area identifier that uniquely identifies the power supply area 70 to which the charging station 30 belongs. The station management list is updated when any changes occur to the contents.

As shown in FIG. 3B, the vehicle management list registers the following items in association with each other: vehicle identifier, vehicle location, charging status, predicted AC charging time, and predicted DC charging time. The vehicle identifier is an identifier that uniquely identifies the vehicle 12. The vehicle location indicates whether the vehicle 12 is within the power supply area 70. The charging status indicates whether the vehicle is being charged. The vehicle management list is updated each time the predicted AC charging time and predicted DC charging time are obtained from each vehicle 12. The vehicle management list is also updated each time the identifier of a vehicle being charged is obtained from the power supply equipment 14.

The detailed operations of the power supply equipment 14, the server device 16, and the vehicle 12 will be described below with reference to Figures 4 to 6. Figure 4 is a flowchart that explains the relationship between the flow of operations of the power supply equipment 14 and the flow of operations of the server device 16.

When a predetermined interrupt timing occurs at a predetermined control cycle, the equipment control unit 34 of the power supply equipment 14 starts the following periodic equipment processing (S100). In the periodic equipment processing, the equipment control unit 34 first transmits equipment information of its own equipment to the server device 16 (S110). In other words, the equipment control unit 34 transmits the station identifier, charging method, and available charging output amount for all charging stations 30 of the power supply equipment 14 to the server device 16.

The server control unit 82 of the server device 16 receives the equipment information transmitted from the power supply equipment 14 (S111). The server control unit 82 then stores the received equipment information in the server storage unit 84, thereby updating the station management list in the management list 86 (S112).

Next, the equipment control unit 34 of the power supply equipment 14 transmits the identifier of the vehicle currently being charged to the server device 16 (S120) and ends the equipment periodic processing (S130).

The server control unit 82 of the server device 16 receives the identifier of the vehicle being charged transmitted from the power supply equipment 14 (S121). The server control unit 82 then updates the vehicle management list of the management list 86 by storing the charging status corresponding to the received vehicle identifier as being in charging in the server storage unit 84 (S122).

Figure 5 is a flowchart that explains the relationship between the flow of periodic operations of vehicle 12 and the flow of operations of server device 16. In Figure 5, vehicle 12A is used as an example, but the same periodic operations as vehicle 12A are also performed for other vehicles 12B and 12C that are not being charged.

When a predetermined interrupt timing occurs at a predetermined control period, the charging control unit 48 of the vehicle 12A starts the following vehicle periodic processing. Note that the predetermined control period for the vehicle periodic processing is, for example, one minute, but may be set arbitrarily as long as it can be appropriately reflected in the management list 86.

In the vehicle periodic processing, the charging control unit 48 of the vehicle 12A first determines whether the vehicle is present within the power supply area 70 (S210). For example, the location information of the power supply area 70 is registered in advance in the vehicle memory unit 44. The charging control unit 48 acquires the location information of the vehicle based on the GPS of the navigation device. When the location information of the vehicle matches the location information of the power supply area 70 within the allowable error range, the charging control unit 48 determines that the vehicle is present within the power supply area 70.

If the vehicle is present within the power supply area 70 (YES in S210), the expected value derivation unit 62 of the vehicle 12A derives an AC charging execution expected value (S220). Specifically, the expected value derivation unit 62 reads the charging history data 52. The expected value derivation unit 62 also obtains the current SOC of the vehicle. The expected value derivation unit 62 applies the current SOC to the charging history data 52 to obtain the number of AC chargings and the total number of chargings in the category corresponding to the current SOC. The expected value derivation unit 62 then divides the obtained number of AC chargings by the obtained total number of chargings to derive an AC charging execution expected value (AC charging execution expected value = number of AC chargings / total number of chargings).

For example, referring to the example in FIG. 2, if the current SOC is 25%, this corresponds to category "3" where the SOC is greater than 20% and less than or equal to 30%. The expected value derivation unit 62 obtains the number of AC charges "18" and the total number of charges "360" in category "3". The expected value derivation unit 62 then divides the number of AC charges by the total number of charges (18/360) to derive an AC charging execution expected value of "0.05".

Next, the expected value derivation unit 62 of the vehicle 12A derives a DC charging execution expected value (S230). Specifically, the expected value derivation unit 62 applies the current SOC to the charging history data 52 to obtain the number of DC charging times and the total number of charging times corresponding to the current SOC. Then, the expected value derivation unit 62 divides the obtained number of DC charging times by the obtained total number of charging times to derive a DC charging execution expected value (DC charging execution expected value = number of DC charging times / total number of charging times).

For example, the expected value derivation unit 62 obtains the number of DC charges of "40" and the total number of charges of "360" in category "3." The expected value derivation unit 62 then divides the number of DC charges by the total number of charges (40/360) to derive the DC charging execution expected value of "0.11."

The expected value derivation unit 62 can derive the expected value for AC charging execution and the expected value for DC charging execution that take into account the possibility of whether or not charging will be performed, regardless of whether charging is AC charging or DC charging, by dividing by the total number of charging attempts.

Next, the estimated charging time derivation unit 64 of the vehicle 12A transmits an equipment information request to the server device 16 (S240). The equipment information request indicates a request to transmit the total AC possible charging output amount and the total DC possible charging output amount for the power supply equipment 14 in the power supply area 70 to which the vehicle belongs. The equipment information request may also include the vehicle identifier of the requesting vehicle and information on the vehicle position.

The total AC possible charging output amount indicates the sum of the possible charging output amounts of each AC stand 30A in the power supply area 70 for all AC stands 30A in the power supply area 70. In other words, the total AC possible charging output amount indicates the sum of the amount of power that can be supplied by the AC stands 30A in the power supply area 70. For example, referring to the example in FIG. 3A, the total AC possible charging output amount corresponds to the possible charging output amount of "20 kWh" of the stand identifier "Std1".

The total possible DC charging output amount indicates the sum of the possible charging output amount of each DC stand 30D in the power supply area 70 for all DC stands 30D in the power supply area 70. In other words, the total possible DC charging output amount indicates the sum of the amount of power that can be supplied by the DC stands 30D in the power supply area 70. For example, referring to the example in FIG. 3A, the total possible DC charging output amount corresponds to "300 kWh", which is the sum of the possible charging output amount of "150 kWh" of stand identifier "Std2" and the possible charging output amount of "150 kWh" of stand identifier "Std3".

When the server control unit 82 of the server device 16 receives a facility information request (S241), it interprets the contents of the facility information request and creates information to be sent to the vehicle 12A (S242). For example, the server control unit 82 identifies the power supply area 70 and the charging station 30 based on the vehicle position information of the vehicle 12A, and derives the total AC possible charging output amount and the total DC possible charging output amount of the identified charging station 30. The server control unit 82 then transmits the derived total AC possible charging output amount and total DC possible charging output amount as facility information to the requesting vehicle 12A (S243).

The charging control unit 48 of the vehicle 12A receives the facility information transmitted from the server device after the facility information request is transmitted (S250). This allows the charging control unit 48 to obtain the total AC possible charging output amount and the total DC possible charging output amount within the power supply area 70 in which the vehicle is located.

The server control unit 82 may transmit the possible charging output amount of each AC stand 30A in the power supply area 70 instead of the total possible AC charging output amount, and transmit the possible charging output amount of each DC stand 30D in the power supply area 70 instead of the total possible DC charging output amount. In this case, the charging control unit 48 derives the total possible AC charging output amount from the possible charging output amount of each AC stand 30A received, and derives the total possible DC charging output amount from the possible charging output amount of each DC stand 30D received.

Next, the charging control unit 48 of the vehicle 12A derives an AC charging predicted time of the vehicle (S260). Specifically, the charging control unit 48 derives a current charging capacity corresponding to the current SOC based on the current SOC of the vehicle. The charging control unit 48 subtracts the current charging capacity from the full charging capacity to derive a current chargeable energy amount of the vehicle. In other words, the chargeable energy amount indicates a reduction in the charging capacity from the full charging capacity. Then, the charging control unit 48 derives an AC charging predicted time by the following formula (1) based on the current chargeable energy amount of the vehicle, the total AC possible charging output amount in the power supply area 70, and the AC charging execution expected value of the vehicle.
AC charging predicted time=(chargeable energy amount/total possible AC charging output amount)
× AC charging execution expected value ... (1)

For example, assume that the current chargeable energy amount of vehicle 12A is "10 kWh." Also assume that the total AC possible charging output amount is "20 kWh" and the expected AC charging execution value is "0.05." In this case, the predicted AC charging time is "(10 kWh/20 kWh) x 0.05 = 0.02 hours."

Next, the charging control unit 48 of the vehicle 12A derives a DC charging predicted time of the vehicle (S270). Specifically, the charging control unit 48 derives the DC charging predicted time based on the current chargeable energy amount of the vehicle, the total DC possible charging output amount within the power supply area 70, and the DC charging execution expected value of the vehicle, using the following formula (2).
DC charging predicted time=(chargeable energy amount/total possible DC charging output amount)
× DC charging execution expected value ... (1)

For example, assume that the current chargeable energy amount of vehicle 12A is "10 kWh." Also assume that the total possible DC charging output amount is "150 kWh x 2 = 300 kWh," and the expected DC charging execution value is "0.11." In this case, the predicted DC charging time is "(10 kWh/300 kWh) x 0.11 = 0.003 h."

Next, the charging control unit 48 of the vehicle 12A transmits the vehicle information of the vehicle to the server device 16 (S280) and ends the vehicle periodic processing (S290). The transmitted vehicle information includes the vehicle identifier of the vehicle, the predicted AC charging time of the vehicle derived in step S260, and the predicted DC charging time derived in step S270.

When the server control unit 82 of the server device 16 receives vehicle information from the vehicle 12A (S281), the server control unit 82 updates the vehicle management list of the management list 86 by storing the received information in the server storage unit 84 (S282). As a result, the latest predicted AC charging time and predicted DC charging time for the vehicle 12A are reflected in the management list 86.

Also, in step S210, if the vehicle is outside the power supply area 70 (NO in S120), the charging control unit 48 ends the vehicle regular processing (S290).

Figure 6 is a flowchart explaining the operation flow of the congestion prediction time derivation unit. The congestion prediction process is a process for deriving either or both of the AC congestion prediction time and the DC congestion prediction time. In Figure 6, vehicle 12A is used as an example, but the same congestion prediction process as vehicle 12A can also be performed for other vehicles 12B, 12C, and 12D that are not charging.

The congestion prediction time derivation unit 66 of vehicle 12A starts the congestion prediction process in response to a user operation that instructs the start of congestion prediction (S300).

The congestion prediction time derivation unit 66 first transmits a target vehicle information request to the server device 16, requesting information on the target vehicle that is the subject of the calculation (S310). The target vehicle is a vehicle that is not being charged and is present within the power supply area 70, excluding the vehicle itself. The target vehicle information request may include the vehicle identifier of the requesting vehicle and information on the vehicle position.

When the server control unit 82 of the server device 16 receives a target vehicle information request (S311), it determines the target vehicle (S312). For example, the server control unit 82 identifies the power supply area 70 based on the requester's vehicle position information, and identifies candidate vehicles within the power supply area 70. If the requester's vehicle 12 is included in the candidate vehicles within the identified power supply area 70, the server control unit 82 excludes the requester's vehicle 12. In this manner, the target vehicle is determined. For example, if vehicle 12A is the requester of the target vehicle information request, vehicles 12B and 12C, excluding the requester's vehicle 12A, among the candidate vehicles present within the power supply area 70, are determined as the target vehicles.

After determining the target vehicle, the server control unit 82 transmits target vehicle information, which is vehicle information of the determined target vehicle, to the requesting vehicle 12 (S313). The target vehicle information includes the predicted AC charging time and predicted DC charging time of the target vehicle. In other words, the server control unit 82 obtains the predicted AC charging time and predicted DC charging time of each of vehicles 12B and 12C determined as the target vehicles from the management list 86 and transmits them to vehicle 12A.

The congestion prediction time derivation unit 66 of the vehicle 12A receives the target vehicle information transmitted from the server device after the target vehicle information request is transmitted (S320). This allows the congestion prediction time derivation unit 66 to obtain the AC charging prediction time and the DC charging prediction time of the target vehicle.

Next, the congestion predicted time derivation unit 66 of vehicle 12A adds up the acquired AC charging predicted times of the target vehicles to derive the AC congestion predicted time (S330). For example, vehicles 12B and 12C are the target vehicles, and referring to the example of FIG. 3B, the AC charging predicted time of vehicle 12B is "0.07 h" and the AC charging predicted time of vehicle 12C is "0.05 h". In this case, the AC congestion predicted time of vehicle 12A is "0.07 h + 0.05 h = 0.12 h", which is the sum of the AC charging predicted time of vehicle 12B "0.07 h" and the AC charging predicted time of vehicle 12C "0.05 h".

Next, the congestion predicted time derivation unit 66 of vehicle 12A adds up the acquired DC charging predicted times of the target vehicles to derive the DC congestion predicted time (S340). For example, vehicles 12B and 12C are the target vehicles, and referring to the example of FIG. 3B, the DC charging predicted time of vehicle 12B is "0.006h" and the DC charging predicted time of vehicle 12C is "0.002h". In this case, the DC congestion predicted time of vehicle 12A is "0.006h + 0.002h = 0.008h", which is the sum of the DC charging predicted time of vehicle 12B "0.006h" and the DC charging predicted time of vehicle 12C "0.002h".

Next, the congestion prediction time derivation unit 66 of the vehicle 12A notifies a predetermined notification unit of the derivation results of the AC congestion prediction time and the DC congestion prediction time (S350), and ends the congestion prediction process (S360). For example, the congestion prediction time derivation unit 66 displays the derivation results on a display of a navigation device, etc.

This allows the user to distinguish between the degree of congestion of AC charging and the degree of congestion of DC charging. As a result, the user can make plans such as whether to perform AC charging or DC charging.

The congestion prediction process can also be performed for vehicle 12D outside the power supply area. In this case, the server control unit 82 determines vehicle 12A, vehicle 12B, and vehicle 12C, which are candidate vehicles within the power supply area 70, as target vehicles. Then, the server control unit 82 obtains the AC charging predicted time and DC charging predicted time for each of vehicle 12A, vehicle 12B, and vehicle 12C from the management list 86 and transmits them to vehicle 12D.

The congestion predicted time derivation unit 66 of the vehicle 12D derives the AC congestion predicted time by adding up the AC charging predicted times of the vehicles 12A, 12B, and 12C. For example, in the example of FIG. 3, the AC congestion predicted time of the vehicle 12D is "0.02h + 0.07h + 0.05h = 0.14h". The congestion predicted time derivation unit 66 of the vehicle 12D derives the DC congestion predicted time by adding up the DC charging predicted times of the vehicles 12A, 12B, and 12C. For example, in the example of FIG. 3, the DC congestion predicted time of the vehicle 12D is "0.003h + 0.006h + 0.002h = 0.011h". The congestion predicted time derivation unit 66 of the vehicle 12D then displays the derived result on a display or the like.

This allows the user of vehicle 12D outside power supply area 70 to distinguish between the degree of congestion for AC charging and the degree of congestion for DC charging when charging in power supply area 70. As a result, the user of vehicle 12D can decide before entering power supply area 70 whether to stop by this power supply area 70 and use AC charging or DC charging, or to postpone charging until a power supply area 70 is further ahead.

As described above, in the charging system 1 of this embodiment, the predicted AC congestion time for a specific vehicle is derived based on the predicted AC charging time for target vehicles other than the specific vehicle among the candidate vehicles present in the power supply area. Also, in the charging system 1 of this embodiment, the predicted DC congestion time for a specific vehicle is derived based on the predicted DC charging time for target vehicles other than the specific vehicle among the candidate vehicles present in the power supply area.

Therefore, with the charging system 1 of this embodiment, it is possible to distinguish and grasp the degree of congestion of AC charging and the degree of congestion of DC charging, and it is possible to grasp the potential demand for charging for each charging method. Furthermore, with the charging system 1 of this embodiment, it is possible to more accurately predict the degree of congestion for each charging method.

Figure 7 is a flowchart that explains a modified example of the operation of the congestion predicted time derivation unit 66. In the example of Figure 6 above, both the AC congestion predicted time and the DC congestion predicted time were derived. In contrast, in the example of Figure 7, either the AC congestion predicted time or the DC congestion predicted time is derived, and derivation of the other is allowed to be omitted.

As shown in FIG. 7, the congestion predicted time derivation unit 66 of vehicle 12A is similar to that in FIG. 6 up to the point that it acquires the AC charging predicted time and the DC charging predicted time of the target vehicle as target vehicle information (S320). In FIG. 7, the explanation of the points in common with FIG. 6 is omitted, and the points different from FIG. 6 are described in detail.

After step S320, the congestion prediction time derivation unit 66 of the vehicle 12A acquires the current SOC (S400). Next, the congestion prediction time derivation unit 66 reads the charging history data and acquires the current battery remaining capacity, i.e., the number of AC charges and the number of DC charges for a specified category that corresponds to the current SOC (S410).

When the battery remaining capacity is classified according to the amount of chargeable energy in the charging history data 52, the congestion prediction time derivation unit 66 derives the current amount of chargeable energy based on the current SOC. Then, the congestion prediction time derivation unit 66 obtains the number of AC charges and the number of DC charges for a specified category that corresponds to the current amount of chargeable energy.

The congestion predicted time derivation unit 66 determines whether the acquired number of AC charges is greater than the acquired number of DC charges (S420). If the number of AC charges is greater than the number of DC charges (YES in S420), the congestion predicted time derivation unit 66 derives the AC congestion predicted time for the vehicle (S430) and notifies the notification unit of the derivation result (S350). In other words, in this case, since there is a higher possibility of AC charging than DC charging at the current SOC, the AC congestion predicted time is derived, but the derivation of the DC congestion predicted time is allowed to be omitted.

If the number of AC charges is equal to or less than the number of DC charges (NO in S420), the congestion prediction time derivation unit 66 determines whether the acquired number of DC charges is greater than the acquired number of AC charges (S440). If the number of DC charges is greater than the number of AC charges (YES in S440), the congestion prediction time derivation unit 66 derives a DC congestion prediction time for the vehicle (S450) and notifies the notification unit of the derivation result (S350). In other words, in this case, since there is a higher possibility of DC charging than AC charging at the current SOC, the DC congestion prediction time is derived, but the derivation of the AC congestion prediction time is allowed to be omitted.

If the number of DC charges is less than or equal to the number of AC charges (NO in S440), the congestion prediction time derivation unit 66 derives the AC congestion prediction time (S460), derives the DC congestion prediction time (S470), and notifies the notification unit of the derivation result (S350). In other words, in this case, the possibility of performing AC charging and the possibility of performing DC charging are equal, so both the AC congestion prediction time and the DC congestion prediction time are derived.

In this embodiment, notification of the predicted congestion time for AC charging or DC charging, whichever is less likely to be performed, is omitted. This makes it possible to reduce the burden on the user, who would otherwise have to consider excessive information when deciding whether to perform charging.

In addition, the congestion prediction time derivation unit 66 of a vehicle 12 that is equipped with only one of the AC charging port 50A and the DC charging port 50D may omit deriving the congestion prediction time for an infeasible charging method without comparing the number of AC charges and the number of DC charges.

Although an embodiment of the present invention has been described above with reference to the attached drawings, it goes without saying that the present invention is not limited to such an embodiment. It is clear that a person skilled in the art can come up with various modified or revised examples within the scope of the claims, and it is understood that these also naturally fall within the technical scope of the present invention.

REFERENCE SIGNS LIST 1 Charging system 12, 12A, 12B, 12C, 12D, 12E, 12F, 12G Vehicle 20 Vehicle-mounted battery 30 Charging stand 30A AC stand 30D DC stand 44 Vehicle storage unit 52 Charging history data 60 Charging execution unit 62 Expected value derivation unit 64 Estimated charging time derivation unit 66 Estimated congestion time derivation unit 70 Power supply area

Claims (4)

a charging execution unit capable of executing at least one of AC charging for charging the vehicle-mounted battery based on AC power supplied from outside the vehicle and DC charging for charging the vehicle-mounted battery based on DC power supplied from outside the vehicle;
a storage unit mounted on the vehicle that stores charging history data indicating a charging history of the AC charging and the DC charging;
an expected value derivation unit that derives, for each vehicle within a predetermined power supply area, an AC charging execution expected value indicating an expected value at which the AC charging will be performed and a DC charging execution expected value indicating an expected value at which the DC charging will be performed, based on the charging history data;
a charging predicted time derivation unit that derives an AC charging predicted time indicating a predicted value of a charging time when the vehicle performs the AC charging based on the AC charging execution expected value, and derives a DC charging predicted time indicating a predicted value of a charging time when the vehicle performs the DC charging based on the DC charging execution expected value;
a congestion predicted time derivation unit that derives an AC congestion predicted time indicating a predicted value of a waiting time until execution of the AC charging for a specific vehicle starts based on the AC charging predicted time for a target vehicle other than the specific vehicle among candidate vehicles present in the power supply area, and derives a DC congestion predicted time indicating a predicted value of a waiting time until execution of the DC charging for the specific vehicle starts based on the DC charging predicted time for the target vehicle;
A charging system comprising: The charging history data is
A plurality of divisions into which the possible range of the remaining battery capacity at the start of charging is divided are preset,
each of the plurality of categories is associated with a predetermined category corresponding to a remaining battery amount at the start of each charge, an AC charging count indicating the number of times the AC charging was started with a remaining battery amount within the predetermined category, and a DC charging count indicating the number of times the DC charging was started with a remaining battery amount within the predetermined category;
The expected value derivation unit
deriving the AC charging execution expected value by dividing the number of AC charging times in the predetermined section corresponding to the current battery remaining amount by a total number of charging times obtained by adding up the number of AC charging times in all sections and the number of DC charging times in all sections;
The charging system according to claim 1 , wherein the DC charging execution expected value is derived by dividing the number of DC charging times in the predetermined section corresponding to a current battery remaining amount by the total number of charging times. The charging system according to claim 2, wherein the congestion prediction time derivation unit derives the AC congestion prediction time if the number of AC charges is greater than the number of DC charges in the predetermined section corresponding to the current battery remaining amount, and derives the DC congestion prediction time if the number of DC charges is greater than the number of AC charges. The charging prediction time derivation unit is
deriving the AC charging predicted time based on a chargeable energy amount indicating a reduction in charging capacity from a full charge capacity of an on-board battery, a total AC possible charging output amount indicating a sum of the amount of power that can be supplied by AC stands used for the AC charging within the power supply area, and the AC charging execution expected value;
4. The charging system according to claim 1, wherein the predicted DC charging time is derived based on the amount of chargeable energy, a total possible DC charging output amount indicating the sum of the amount of power that can be supplied by DC stations used for the DC charging within the power supply area, and the expected value of DC charging execution.

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