Charge and Discharge Control Device

Abstract

Provided is a charge-discharge control device that suppresses deterioration of an in-vehicle battery. The charge-discharge control device disclosed herein controls a charge-discharge device that charges and discharges an in-vehicle battery mounted on an electric vehicle. The charge-discharge control device includes: a detection unit that detects connection of the electric vehicle to the charge-discharge device; an SOC acquisition unit that acquires the SOC of the in-vehicle battery of the electric vehicle connected to the charge-discharge device; a usage information acquisition unit that acquires the next usage time and the next driving distance of the electric vehicle connected to the charge-discharge device; and a setting unit that prepares a charge-discharge schedule for the in-vehicle battery of the electric vehicle in such a manner that charging is performed after maintaining the in-vehicle battery at a low SOC and the SOC required for the next driving distance remains at the next usage time.

Description

Technical Field

[0001] The present invention relates to a charge and discharge control device. Background Art

[0002] In Japanese Patent Application Laid-Open No. 2019-154167, a charging system for an electric vehicle that charges a secondary battery of the electric vehicle with an external charger is disclosed. The charging system for the electric vehicle includes: a charging completion time setting unit that sets a charging completion time for the electric vehicle by a user's operation; and a charging control unit that controls charging of the secondary battery. The charging control unit has a charging mode control unit that controls the following charging mode according to the temperature change and the SOC at the start time of charging control: shortening or eliminating the residence time in the SOC region and the temperature range in which the deterioration of the secondary battery is likely to progress during the period from the start time of charging control to the charging completion time. According to the charging system for the electric vehicle having the above structure, it is possible to suppress the deterioration of the secondary battery during the charge and discharge process using the external charger.

[0003] Prior Art Documents

[0004] Patent Document 1: Japanese Patent Application Laid-Open No. 2019-154167 Summary of the Invention

[0005] However, a technique for effectively using electric power using an in-vehicle battery mounted on an electric vehicle has been proposed. For example, so-called V2G (Vehicle-to-Grid, vehicle to grid) for supplying electric power from an electric vehicle to a power system and so-called V2H (Vehicle-to-Home, vehicle to home) for supplying electric power from an electric vehicle to a home have been proposed. However, the in-vehicle batteries of electric vehicles participating in V2G and V2H may be repeatedly charged and discharged in response to power demand. Depending on the charge and discharge state of the in-vehicle battery, it is possible to advance the deterioration of the in-vehicle battery.

[0006] The charge and discharge control device disclosed herein controls a charge and discharge device that charges and discharges an in-vehicle battery mounted on an electric vehicle. The charge and discharge control device includes: a detection unit that detects that an electric vehicle is connected to the charge and discharge device; an SOC acquisition unit that acquires the SOC of the in-vehicle battery of the electric vehicle connected to the charge and discharge device; a usage information acquisition unit that acquires the next usage time and the next driving distance of the electric vehicle connected to the charge and discharge device; and a setting unit that prepares a charge and discharge schedule for the in-vehicle battery of the electric vehicle so as to charge after maintaining the in-vehicle battery at a low SOC and leave the SOC required for the next driving distance at the next usage time. By configuring the charge and discharge control device as described above, the deterioration of the in-vehicle battery is reduced.

[0007] The low SOC can also be set to be below the SOC that suppresses deterioration of the in-vehicle battery. The low SOC can also be set to be above the SOC that enables traveling a predetermined distance.

[0008] The charge / discharge control device may further include: a history acquisition unit that acquires the usage history of the electric vehicle; a storage unit that stores the usage history; and a determination unit that determines at least one of the next usage time and the next traveling distance based on the stored usage history. The charge / discharge control device may further include: a reservation acquisition unit that acquires the reservation information of the electric vehicle; and a determination unit that determines at least one of the next usage time and the next traveling distance based on the reservation information.

[0009] The charge / discharge control device may further include a demand acquisition unit that acquires the variation in power demand in the power system. The setting unit may set the charge / discharge schedule in such a way that the in-vehicle battery discharges to the power system when the power demand in the power system is high. The setting unit may set the charge / discharge schedule in such a way that the in-vehicle battery is charged from the power system when the power demand in the power system is low.

[0010] The SOC after charging can also be adjusted to be able to supply predetermined power to predetermined electrical equipment from the in-vehicle battery. The setting unit may set the charge / discharge schedule in such a way that power is supplied to the electrical equipment at a predetermined timing. Description of the Drawings

[0011] Figure 1 is a conceptual diagram showing the connection relationship of the charge / discharge management system 100.

[0012] Figure 2 is a block diagram showing the charge / discharge management system 100.

[0013] Figure 3 is a flowchart showing the process of the processing implemented by the control device 50.

[0014] Figure 4 is a graph showing an example of the variation in the power amount of the in-vehicle battery 12. Detailed Description of the Embodiment

[0015] Hereinafter, with reference to the drawings, an embodiment of the charge / discharge control device disclosed herein will be described. The embodiment described here is clearly not intended to particularly limit the present invention. In the present invention, unless otherwise particularly mentioned, it is not limited to the embodiment described here. In addition, the same reference numerals are appropriately added to the components / parts that perform the same function, and the repeated description is appropriately omitted.

[0016] <Charge / Discharge Management System 100>

[0017] Figure 1 is a conceptual diagram showing the connection relationship of the charge-discharge management system 100. Figure 2 is a block diagram showing the charge-discharge management system 100. As Figure 1 shown, the charge-discharge management system 100 includes a user terminal 15, a charge-discharge device 20, and a control device 50. Although not shown in the figure, the charge-discharge management system 100 includes a power storage device that stores electric power. The charge-discharge management system 100 manages: charging the in-vehicle battery 12 of the electric vehicle 10 with the electric power stored in the power storage device; and storing the electric power discharged from the in-vehicle battery 12 of the electric vehicle 10 in the power storage device. The electric power stored in the power storage device is sold to a specific operator such as an electric power company. The charge-discharge management system 100 can be a system used when buying and selling electric power, that is, selling electricity and purchasing electricity. The charge-discharge management system 100 is implemented, for example, by a client-server system. However, the charge-discharge management system 100 can also be implemented by cloud computing.

[0018] The charge-discharge management system 100 is managed by a system administrator. The system administrator is also called an aggregator. The system administrator adjusts the amount of electric power in a way that ensures the balance between the demand and supply of electric power. For example, the system administrator supplies electric power according to the requirements of a specific operator such as an electric power company and supplies electric power to the specific operator. Therefore, in order to ensure the required amount of electric power, the system administrator preferably signs more contracts with the users of the electric vehicle 10 and the administrators who manage the charge-discharge device 20 for using the charge-discharge management system 100. The electric vehicle 10, the users who use the electric vehicle 10, and the charge-discharge device 20 are registered in the charge-discharge management system 100. The charge-discharge management system 100 manages electric power by supplying electric power (here, charging) from the charge-discharge device 20 to the electric vehicle 10, or supplying electric power (here, discharging) from the electric vehicle 10 to the charge-discharge device 20.

[0019] <Electric vehicle 10>

[0020] The electric vehicle 10 is a vehicle equipped with an in-vehicle battery 12 that can be charged and discharged. The electric vehicle 10 runs using the electric power obtained from the in-vehicle battery 12 as an energy source. The electric vehicle 10 includes vehicles that use electric power as an energy source, such as battery electric vehicles (BEV: Battery Electric Vehicle), hybrid electric vehicles (HEV: Hybrid Electric Vehicle), and plug-in hybrid electric vehicles (PHEV: Plug-in Hybrid Electric Vehicle). The electric vehicle 10 can be either a four-wheeled vehicle or a two-wheeled vehicle. The electric vehicle 10 participates in V2G and V2H. That is, the electric vehicle 10 can supply electric power to the power system 30 and the home (residence) 40 via the charging and discharging device 20.

[0021] The user of the electric vehicle 10 uses the user terminal 15. The user terminal 15 can be used as a terminal for managing information related to the use, charging and discharging, etc. of the electric vehicle 10. The user terminal 15 can be, for example, a vehicle navigation system installed in the electric vehicle 10, or a smart phone, a tablet terminal, a desktop or portable personal computer used by the user. The user terminal 15 is provided with an input unit 17 and a terminal control device 18 (refer to Figure 2 ). The input unit 17 is, for example, a touch panel, a keyboard, or a mouse, etc., which is a unit for the user to perform operations and input. The terminal control device 18 is communicably connected to the input unit 17 (refer to Figure 2 ). The user terminal 15 also has a screen, etc., for the user to confirm the charging and discharging status, etc. of the in-vehicle battery 12.

[0022] However, the usage status of the battery and the charging and discharging status of the battery will affect the battery life of the in-vehicle battery 12. For example, due to maintaining for a long time in a state where the charging rate of the battery is high, that is, a so-called high SOC (States Of Charge), or repeatedly charging or discharging quickly, etc., the deterioration of the battery may progress. Based on the idea of the present inventor, for example, it is assumed that the electric vehicle 10 participating in V2G and V2H keeps the in-vehicle battery 12 at a high SOC for a longer time in order to meet the power demand. As a result, the deterioration of the in-vehicle battery 12 may progress.

[0023] <Charging and discharging device 20>

[0024] The charging and discharging device 20 is a device for charging and discharging (hereinafter also referred to as charging and discharging) the in-vehicle battery 12 mounted on the electric vehicle 10. The charging and discharging device 20 is, for example, installed at a charging spot set in a home, an office, a commercial facility, a hospital, a gas station, an automobile dealership, etc. The charging and discharging device 20 is provided with a connector 21 (refer toFigure 2 )。The in-vehicle battery 12 of the electric vehicle 10 is charged and discharged via the connector 21 of the charge and discharge device 20. As the connector 21, for example, a charge and discharge cable or the like can be used. The charge and discharge device 20 is configured to supply power to the power system 30 and the home 40 from the in-vehicle battery 12 via the connector 21.

[0025] The charge and discharge device 20 further includes a communication unit 22, a setting unit 23, an execution unit 24, and an acquisition unit 25 (see Figure 2 ). Each of the units 22 to 25 constitutes a control device of the charge and discharge device 20. Each of the units 22 to 25 can be implemented by one or more processors or incorporated into a circuit.

[0026] In the setting unit 23, a charge and discharge condition database DB1 is registered. In the charge and discharge condition database DB1, the charge and discharge conditions when charging and discharging the in-vehicle battery 12 are registered. As the charge and discharge conditions, the current, voltage, charge and discharge time, etc. during charge and discharge are associated with the charge and discharge amount of the in-vehicle battery 12 and registered. In addition, in the charge and discharge condition database DB1, the charge and discharge conditions for obtaining the SOC for calculating the SOC of the in-vehicle battery 12 are also registered.

[0027] In this embodiment, the charge and discharge device 20 includes a charge and discharge device 20a owned by the user. The charge and discharge device 20a is installed in the parking lot of the user's residence in a manner that facilitates charging and discharging the in-vehicle battery 12 of the electric vehicle 10 owned by the user himself / herself. The charge and discharge device 20a is connected to the electrical equipment of the user's home 40. The charge and discharge device 20a is configured to be able to supply the power of the in-vehicle battery 12 to the home 40 as well.

[0028] <Power system 30>

[0029] The power system 30 is a system composed of electrical equipment for power generation, transmission, transformation, distribution, etc. The demand side is connected to the power system 30 via a transmission line or the like. The power system 30 supplies power to the electrical equipment of the demand side according to the power demand.

[0030] <Home 40>

[0031] The home 40 is the residence of the user who owns the electric vehicle 10. In this embodiment, the home 40 is equipped with a solar power generation device 42. The home 40 is connected to the electric vehicle 10 and the power system 30 via the charge and discharge device 20a. The power generated by the solar power generation device 42 is used within the home 40. The remaining power is configured to be able to be supplied (i.e., sold) to the power system 30 or charge the in-vehicle battery 12 of the electric vehicle 10 via the charge and discharge device 20a.

[0032] <Charge and discharge control device 50>

[0033] The charge-discharge control device 50 (hereinafter also simply referred to as the control device 50) controls the charge and discharge of the in-vehicle battery 12 of the electric vehicle 10 by the charge-discharge device 20. The structure of the control device 50 is not particularly limited. Here, the control device 50 is, for example, a microcomputer. The control device 50 includes, for example, an I / F, a CPU, a ROM, and a RAM. The control device 50 may be constituted by a single computer or by a plurality of computers.

[0034] As Figure 2 shown, the control device 50 includes a first communication unit 51 and a second communication unit 52. The control device 50 further includes a storage unit 60, a detection unit 61, a calculation unit 62, an SOC acquisition unit 63, a usage information acquisition unit 64, a history acquisition unit 65, a determination unit 66, a schedule acquisition unit 67, a setting unit 68, a demand acquisition unit 69, and a prediction unit 70. Each of the units 51 to 70 included in the control device 50 may be implemented by one or more processors or incorporated into a circuit.

[0035] The first communication unit 51 is configured to be able to communicate with the charge-discharge device 20. Here, the first communication unit 51 is communicably connected to the communication unit 22 of the charge-discharge device 20. The second communication unit 52 is configured to be able to communicate with the user terminal 15 of the user who uses the electric vehicle 10. Here, the second communication unit 52 is communicably connected to the terminal control device 18 of the user terminal 15. The storage unit 60 pre-stores an SOC database DB2, an action information database DB3, and a power demand database DB4.

[0036] Figure 3 is a flowchart showing the process of the processing implemented by the control device 50. The control device 50 is configured to implement the following processes A to D: Process A, detecting that the electric vehicle 10 is connected to the charge-discharge device 20; Process B, acquiring the SOC of the in-vehicle battery 12 of the electric vehicle 10 connected to the charge-discharge device 20; Process C, acquiring the next use time and the next driving distance of the electric vehicle 10 connected to the charge-discharge device 20; Process D, preparing a charge-discharge schedule for the electric vehicle 10 in such a way that, at least based on the next use time and the next driving distance, after maintaining the in-vehicle battery 12 at a predetermined low SOC, charging is performed and the SOC required for the next driving distance remains at the next use time. For example, by connecting the electric vehicle 10 to the connector 21 of the charge-discharge device 20, these processes are started. Hereinafter, each process will be specifically described.

[0037] <Process A of detecting the connection of the electric vehicle 10>

[0038] When the electric vehicle 10 is connected to the connector 21 of the charging / discharging device 20, the charging / discharging device 20 sends a connection signal to the control device 50 via the communication unit 22. The control device 50 receives the connection signal through the first communication unit 51. The detection unit 61 detects that the electric vehicle 10 is connected to the charging / discharging device 20( Figure 3 in S101).

[0039] <Process B for obtaining the SOC of the in-vehicle battery 12>

[0040] When the detection unit 61 detects in Process A that the electric vehicle 10 is connected to the charging / discharging device 20, the control device 50 sends an SOC acquisition signal to the charging / discharging device 20 via the first communication unit 51( Figure 3 in S103). The charging / discharging device 20 receives the SOC acquisition signal via the communication unit 22. When the SOC acquisition signal is received, the setting unit 23 sets the charging / discharging conditions according to the SOC acquisition charging / discharging conditions registered in the charging / discharging condition database DB1. The execution unit 24 performs charging / discharging on the in-vehicle battery 12 of the electric vehicle 10 under the SOC acquisition charging / discharging conditions set by the setting unit 23. During charging / discharging, the acquisition unit 25 acquires SOC calculation information. The SOC calculation information can be, for example, the charging / discharging current and the charging / discharging voltage. The SOC calculation information acquired by the acquisition unit 25 is sent to the control device 50 via the communication unit 22.

[0041] In addition, in this embodiment, the charging / discharging condition database DB1 is registered in the setting unit 23, but it is not limited to the above method. For example, the charging / discharging condition database DB1 may be stored in the storage unit 60 of the control device 50, and the charging / discharging conditions are sent together when the SOC acquisition signal is sent.

[0042] The control device 50 receives the SOC calculation information via the first communication unit 51( Figure 3 in S105). The calculation unit 62 of the control device 50 calculates the SOC based on the received SOC calculation information. In this embodiment, the SOC is calculated according to the SOC calculation data registered in the SOC database DB2. The SOC calculation data is registered, for example, as data representing the relationship between the charging / discharging current-charging / discharging voltage curve and the SOC. For example, the SOC is calculated by comparing the charging / discharging current and the charging / discharging voltage as the SOC calculation information with the SOC calculation data. The SOC acquisition unit 63 acquires the calculated SOC of the in-vehicle battery 12( Figure 3 in S107). The acquired SOC is used when preparing the schedule in the subsequent Process D. In addition, it is stored in the acquired SOC database DB2. The stored SOC information can be used, for example, for the calculation of the SOC in the future and the deterioration progress information of the in-vehicle battery 12.

[0043] <Process C for obtaining the next usage time and next driving distance of the electric vehicle 10>

[0044] In Process C, the usage information acquisition unit 64 acquires the next usage time and next driving distance of the electric vehicle 10. For example, the usage information acquisition unit 64 can also acquire information related to the next usage time and next driving distance input by the user to the user terminal 15 via the second communication unit 52. For example, the usage information acquisition unit 64 can also acquire the next usage time and next driving distance that match the user's action pattern from the usage history of the electric vehicle 10. The usage history can be, for example, information such as the driving distance, location information, and usage purpose of the electric vehicle 10 associated with time. The usage history can include information such as the usage start time, the usage time period, the driving distance, the usage end time, the usage frequency, and the charge / discharge history. The usage history is stored in the action information database DB3.

[0045] In this embodiment, Process C for obtaining the next usage time and next driving distance includes: a process of acquiring and storing the usage history of the electric vehicle 10 ( Figure 3 S109); and a process of determining at least one of the usage start time and the predetermined driving distance based on the stored usage history ( Figure 3 S111).

[0046] <Process of acquiring and storing the usage history>

[0047] The history acquisition unit 65 acquires the usage history ( Figure 3 S109). For example, the usage history is acquired through a communication control device (not shown) of the electric vehicle 10. The communication control device sends the acquired usage history to the user terminal 15. The user terminal 15 sends the usage history to the control device 50 via the terminal control device 18. The history acquisition unit 65 acquires the received usage history. The storage unit 60 stores the usage history acquired by the history acquisition unit 65 in the action information database DB3. The frequency and method of sending the usage history acquired by the electric vehicle 10 to the control device 50 are not particularly limited. For example, the usage history can also be automatically sent from the user terminal 15 to the control device 50 at a predetermined interval such as once a day. The usage history can also be sent from the user terminal 15 to the control device 50 at a timing specified by the user. In addition, the usage history can also be sent to the control device 50 via the charge / discharge device 20. For example, when the electric vehicle 10 is equipped with the user terminal 15, the usage history can be acquired by the charge / discharge device 20 when the electric vehicle 10 is connected to the connector 21 and sent to the control device 50 via the communication unit 22.

[0048] <Process of determining the next usage time and next driving distance>

[0049] The determination unit 66 determines at least one of the next use time and the next driving distance ( Figure 3 in S111). In this embodiment, the determination unit 66 performs processing to determine both the next use time and the next driving distance based on the usage history.

[0050] The determination unit 66 learns the user's action pattern and the usage pattern of the electric vehicle 10 based on the usage history, and thus can determine the next use time and the next driving distance. For example, on the user's workday, the next use time and the next driving distance can be determined based on the tendency of the use start time and the driving distance included in the usage history of the previous workday. On a rest day, the next use time and the next driving distance different from those on the workday can be determined. If the user hardly drives on a rest day, the next use time can be set to be later and the next driving distance can be set to be shorter on the rest day. If the user drives long distances on a rest day in many cases, the next use time can be set to be earlier and the next driving distance can be set to be longer. In addition, the next driving distance can also be different from the driving distance of one day. The next driving distance can be the driving distance until the connection to the charging and discharging device 20 after the start of use. For example, when there is a charging and discharging device 20 at the user's workplace and the electric vehicle 10 can be charged until the end of work, the next driving distance on the workday can be the one-way distance to the workplace.

[0051] In addition, the process C of obtaining the next use time and the next driving distance may also include: the process of obtaining the scheduled information of the electric vehicle 10 ( Figure 3 in S115); and the process of determining at least one of the next use time and the next driving distance based on the scheduled information ( Figure 3 in S117). In this embodiment, the process C further includes a process of determining whether scheduled information is registered in the user terminal 15 ( Figure 3 in S113). When it is determined that scheduled information is registered in the user terminal 15, the process of obtaining the scheduled information (S115) is then executed. Then, the process of determining at least one of the next use time and the next driving distance (S117) is executed. Thereby, the next use time and the next driving distance are newly determined and updated.

[0052] <Process of determining whether scheduled information is registered>

[0053] The reservation acquisition unit 67 determines whether there is scheduled information for using the electric vehicle 10 within a certain period (for example, within 24 hours) registered in the user terminal 15 ( Figure 3 in S113). When scheduled information is registered in the user terminal 15, the determination becomes "Yes", and the process proceeds to the process of obtaining the scheduled information of the electric vehicle 10Figure 3 If the predetermined information is not registered in the user terminal 15, the determination is made to be "No", and the process proceeds to setting the charging and discharging schedule of the electric vehicle 10 ( Figure 3 S119).

[0054] <Processing of Acquiring Predetermined Information of Electric Vehicle 10>

[0055] The schedule acquisition unit 67 acquires the schedule information ( Figure 3 S115). The user terminal 15 sends the registered reservation information to the control device 50 via the terminal control device 18. The reservation acquisition unit 67 acquires the received reservation information. The reservation information may be, for example, a usage reservation registered in the software that manages the electric vehicle 10. The reservation information may be, for example, a schedule registered in the software that manages the schedule of the user terminal 15. The transmission of the reservation information may be performed automatically from the user terminal 15, or may be performed by the user inputting it using the input unit 17 of the user terminal 15.

[0056] <Processing for determining the next use time and next travel distance>

[0057] The determination unit 66 determines at least one of the next use time and the next travel distance ( Figure 3 In this embodiment, the decision unit 66 performs the following processing: based on the scheduled information obtained by the scheduled acquisition unit 67, the next use time and the next travel distance are determined. Figure 3 The next use time and the next driving distance determined in S111.

[0058] For example, when a destination is registered as scheduled information, the next travel distance may be determined based on the distance to the destination. When there is a charging and discharging device 20 near the destination, the next travel distance may be set shorter. The next use time may also be determined based on the distance to the destination and the time required to reach the expected destination.

[0059] <Processing D of Creating a Charging and Discharging Schedule for Electric Vehicle 10>

[0060] Next, the control device 50 executes a process D for preparing a charge and discharge schedule for the electric vehicle 10. In the process D, the setting unit 68 sets the charge and discharge schedule for the electric vehicle 10 ( Figure 3Of S119). According to the SOC obtained in process B and the next use time and the next driving distance determined in process C, process D is executed. The charge-discharge schedule is determined to be a schedule in which the in-vehicle battery 12 is charged after being maintained at a low SOC and the SOC required for the next driving distance remains at the next use time.

[0061] In addition, in this embodiment, the SOC after charging is adjusted so that the in-vehicle battery 12 can supply predetermined electric power to a predetermined electric device (here, the home 40 (refer to Figure 1 ). In the process D of preparing the schedule, the charge-discharge schedule is set so as to supply electric power to the electric device (here, the home 40) at a predetermined timing. That is, the charge amount and the charging timing are adjusted so that the electric vehicle 10 after supplying power to the home 40 remains at the SOC required for driving the next driving distance.

[0062] In addition, in this specification, the low SOC refers to at least one of the SOC that satisfies being lower than the remaining amount of the SOC of the in-vehicle battery 12 after using the electric vehicle 10 and the SOC that suppresses the deterioration of the in-vehicle battery 12 described later. That is, "maintaining at a low SOC" may mean maintaining the SOC without charging the in-vehicle battery 12 after using the electric vehicle 10, or may mean discharging the in-vehicle battery 12 after using the electric vehicle 10 and maintaining the SOC in a state where the SOC has decreased. In addition, "maintaining at a low SOC" may also mean maintaining the SOC after charging within a range below the SOC that suppresses the deterioration of the in-vehicle battery 12 described later.

[0063] From the viewpoint of suppressing the deterioration of the battery, it is preferable to make the SOC of the in-vehicle battery 12 of the electric vehicle 10 as low as possible. The influence of the SOC on the deterioration of the battery varies depending on the type of the in-vehicle battery 12 and the like, and thus is not particularly limited, but it is preferable to set the low SOC to be below the SOC that suppresses the deterioration of the in-vehicle battery 12. Based on the idea of the present inventor, in order to suppress the deterioration of the in-vehicle battery 12, the SOC of the in-vehicle battery 12 when the electric vehicle 10 is not in use is preferably 70% or less, more preferably 60% or less, and further preferably 50% or less.

[0064] In addition, it is advisable that the SOC of the in-vehicle battery 12 be maintained at a level that can cope with unexpected use or the like even when the electric vehicle 10 is not in use. The low SOC can also be set to be equal to or higher than the SOC that can travel a predetermined distance. Although it also varies depending on lifestyle, residential area, etc., the SOC of the in-vehicle battery 12 when the electric vehicle 10 is not in use can also be set to be able to travel a distance preset by the user or the like, and can also be set based on the usage history according to the user's action pattern for the amount required for driving. The SOC of the in-vehicle battery 12 when the electric vehicle 10 is not in use can be, for example, 10% or more, 15% or more, or 20% or more.

[0065] <Processing E for obtaining the change in power demand in the power system 30>

[0066] In this embodiment, it is configured to perform, in addition to the above-mentioned Processing A to Processing D, Processing E for obtaining the change in power demand in the power system 30. In Processing E, the demand acquisition unit 69 acquires the change in the power demand of the power system ( Figure 3 at S121). The power demand varies, for example, according to time period, climate, day of the week, season, etc. In this embodiment, the past power demand is stored in the power demand database DB4. The prediction unit 70 predicts the change in the power demand during charging / discharging and use of the electric vehicle 10 based on the change in the past power demand stored in the power demand database DB4. The demand acquisition unit 69 acquires the change in the power demand predicted by the prediction unit 70.

[0067] The setting unit 68 adjusts the charge / discharge schedule and the charge / discharge amount ( Figure 3 at S123) in accordance with the change in the power demand acquired by the demand acquisition unit 69. It is also possible to set the timing of discharging in such a way that the in-vehicle battery 12 discharges to the power system 30 when the power demand in the power system 30 is high. In addition, it is also possible to set the timing of charging in such a way that the power system 30 charges the in-vehicle battery 12 when the power demand in the power system 30 is low. It is also possible to adjust the SOC after charging in such a way that a large amount of power can be supplied to the power system 30 when the power demand is high.

[0068] Hereinafter, the days when the electric vehicle 10 is used and the days when the electric vehicle 10 is not used are listed to explain the charge / discharge schedule set according to the usage schedule of the electric vehicle 10 and the change in the power demand. Figure 4 is a graph showing an example of the change in the power amount of the in-vehicle battery 12. In Figure 4 it shows the change in the power amount of the in-vehicle battery 12 for both the days when the electric vehicle 10 is used and the days when the electric vehicle 10 is not used.

[0069] Here, regarding the in-vehicle battery 12 of the electric vehicle 10, the full charge (SOC 100%) capacity is 62 kWh. The power of the charge / discharge device 20 is 4.5 kW (7% / h in terms of SOC). In addition, the household 40 is equipped with a solar power generation device 42. The average daily power generation of the solar power generation device 42 is 20 kWh (about 32% in terms of SOC), and this amount of power can be used in the electric vehicle 10 and the household 40. In the household 40, 9.3 kWh (about 15% in terms of SOC) is consumed during the period from 6 to 8 o'clock, and 4.7 kWh (about 8% in terms of SOC) is consumed during the period from 18 to 20 o'clock, with a total consumption of 14 kWh (about 23% in terms of SOC).

[0070] The power generated by the solar power generation device 42 is preferentially used in the household 40. The power obtained by subtracting the power used in the household 40 from the power generated by the solar power generation device 42 is used for the running of the electric vehicle 10. When the power generated by the solar power generation device 42 is insufficient for the power used in the household 40 and the power used for the running of the electric vehicle 10, charging is performed during a period of low power demand. When the power generated by the solar power generation device 42 is surplus compared to the power used in the household 40 and the power used for the running of the electric vehicle 10, discharging to the power system 30 is performed during a period of high power demand. In addition, in this embodiment, regardless of whether it is a day when the electric vehicle 10 is used or a day when the electric vehicle 10 is not used, the charge / discharge amount is adjusted so that the total charge amount and the total discharge amount are equal.

[0071] <Charge / discharge schedule for a day when the electric vehicle 10 is used>

[0072] In Figure 4 An example of the charge / discharge schedule of the in-vehicle battery 12 on a day when the electric vehicle 10 is used is shown by a solid line. On a day when the electric vehicle 10 is used, the amount of power consumed for the running of the electric vehicle 10 calculated based on the next driving distance (i.e., the round-trip distance to the destination) is 7 kWh (about 11% in terms of SOC). A charge / discharge device 20 is provided at the destination. The next use time (i.e., the start time of use) of the electric vehicle 10 is 8 am. In addition, the lower limit of the power amount is set to the sum of the power amount of 12.4 kWh (about 20% in terms of SOC) for coping with unexpected use and the power amount of 3.5 kWh consumed when driving to the destination. That is, the lower limit of the charge amount is set to 15.9 kWh. When the charge amount is lower than this lower limit charge amount when connected to the charge / discharge device 20, charging is performed until the lower limit charge amount is reached, and then the lower limit charge amount is maintained.

[0073] The amount of power generated by the solar power generation device 42 is 20 kWh, the amount of power consumed in the household 40 is 14 kWh, and the amount of power used for driving the electric vehicle 10 is 7 kWh. Therefore, it is assumed that there will be a shortage of 1 kWh of power. The setting unit 68 sets a charge-discharge schedule in such a way that the shortage of 1 kWh is charged during the period from night to morning when the power demand is low. Thereby, the cost of purchasing electricity can be reduced. As Figure 4 shown, here, during the period from 5:45 am to 6:00 am just before supplying power to the household 40 in the morning, the in-vehicle battery 12 is charged. The charge-discharge schedule is set in such a way that the charging is performed just before use to make the time maintained at a low SOC longer.

[0074] From 6:00 am to 8:00 am, power is supplied from the in-vehicle battery 12 to the household 40. From 8:00 am to 8:30 am, the power of the in-vehicle battery 12 is consumed during the driving of the electric vehicle 10. Even when the destination is reached and the electric vehicle 10 is connected to the charge-discharge device 20, charging is not immediately performed, but the SOC is maintained at a low level. Then, charging starts at 1:00 pm in such a way that charging is completed at 5:30 pm as the next use time. Regarding the charging here, it can also be performed simultaneously with supplying the power generated by the solar power generation device 42 to the power system 30, and thus charging is performed remotely from the solar power generation device 42.

[0075] From 5:30 pm to 6:00 pm, the power of the in-vehicle battery 12 is consumed during the driving of the electric vehicle 10. At 6:00 pm, the electric vehicle 10 is connected to the charge-discharge device 20a. From 6:00 pm to 8:00 pm, power is supplied from the in-vehicle battery 12 to the household 40. Charging is not performed from 8:00 pm, and the low SOC is maintained. At this time, a small amount of the power stored in the in-vehicle battery 12 can be consumed in the household 40. During the period from 5:45 am to 6:00 am on the next day just before supplying power to the household 40, charging is performed to the in-vehicle battery 12.

[0076] <Charge-discharge schedule for days when the electric vehicle 10 is not used>

[0077] In Figure 4 it, a dashed line is used to show an example of the charge-discharge schedule of the in-vehicle battery 12 for days when the electric vehicle 10 is not used. On days when the electric vehicle 10 is not used, the amount of power generated by the solar power generation device 42 is 20 kWh, and the amount of power consumed in the household 40 is 14 kWh. Therefore, it is assumed that there will be a surplus of 6 kWh of power. The setting unit 68 sets a charge-discharge schedule in such a way that the surplus power is supplied to the power system 30 during the period when the power demand is high.

[0078] Similarly to the days when the electric vehicle 10 is used, from 6:00 am to 8:00 am, power is supplied from the in-vehicle battery 12 to the household 40. From 8:00 am to 5:30 pm, the power generated by the solar power generation device 42 is charged into the in-vehicle battery 12. From 6:00 pm to 8:00 pm, the in-vehicle battery 12 discharges. Since the amount of power generated is surplus compared to the power consumption in the household 40, in addition to supplying power to the household 40, power is also supplied to the power system 30, that is, sold. During this evening period, the power demand is generally high. When the power demand is high, by supplying power to the power system 30, the revenue from selling electricity can be increased. From 8:00 pm, charging is not performed and a low SOC is maintained. At this time, a small amount of the power stored in the in-vehicle battery 12 can be consumed in the household 40.

[0079] Here, the charge-discharge schedule has been described by dividing into the days when the electric vehicle 10 is used and the days when the electric vehicle 10 is not used, but it is not necessary to perform charge and discharge according to the set charge-discharge schedule. For example, the set charge-discharge schedule can also be sent to the user terminal 15 via the second communication unit 52. The user can confirm the sent charge-discharge schedule, and the user can adjust the charge-discharge schedule through the input unit 17. For example, on the days when the electric vehicle 10 is not used, when the user wishes to prioritize the suppression of the deterioration of the in-vehicle battery 12 over selling electricity, it can be set to the charge-discharge schedule indicated by the dotted line in Figure 4 That is, it can also be adjusted to the following charge-discharge schedule: starting from 8:00 am when the power consumption in the household 40 ends, neither charging nor discharging is performed, and charging is started from 4:00 am the next day in such a way as to be able to supply power to the household 40 at 6:00 am the next day. In this case, the power generated by the solar power generation device 42 can be consumed in the household 40 and in selling electricity. Although the in-vehicle battery 12 does not participate in the power supply to the power system 30 and the household 40, the period during which the SOC of the in-vehicle battery 12 is low can be further extended. Thereby, the deterioration of the in-vehicle battery 12 can be further suppressed. In addition, during the period from late at night to dawn (for example, from 0:00 am to 6:00 am), the power demand may be relatively low. Therefore, by charging from 4:00 am to 6:00 am, the purchase price of electricity can be suppressed. In this way, various changes can also be made to the set charge-discharge schedule in accordance with the user's needs.

[0080] In the above embodiment, the charge-discharge schedule of the in-vehicle battery 12 of the electric vehicle 10 is prepared in such a way that after maintaining the in-vehicle battery 12 at a low SOC, charging is performed and the SOC required for the next driving distance is left at the next use time. That is, the charge-discharge schedule is set in such a way that the time during which the in-vehicle battery 12 is maintained at a low SOC becomes longer. Thereby, the deterioration of the in-vehicle battery 12 can be reduced.

[0081] In the above-described embodiment, the process C of obtaining the next use time and the next driving distance includes: a process of obtaining and storing the usage history of the electric vehicle 10; and a process of determining at least one of the next use time and the next driving distance based on the stored usage history. By performing the above processes, it becomes easier to determine the charge-discharge schedule, and the burden on the user can be reduced.

[0082] In addition, the process C of obtaining the next use time and the next driving distance includes: a process of obtaining the reservation information of the electric vehicle 10; and a process of determining at least one of the next use time and the next driving distance based on the reservation information. By performing the above processes, for example, even when a reservation different from the daily routine or an emergency reservation is added, the charge-discharge schedule can be appropriately corrected.

[0083] In the above-described embodiment, the SOC after charging is adjusted so that the in-vehicle battery 12 can supply predetermined power to predetermined electrical equipment. In the process D of preparing the schedule, the charge-discharge schedule is set so as to supply power to the electrical equipment at a predetermined timing. Thereby, while suppressing the deterioration of the in-vehicle battery 12, the power demand of the electrical equipment can also be met.

[0084] As described above, various explanations have been given regarding the charge-discharge control device disclosed herein. Unless otherwise specified, the embodiments and the like listed herein do not limit the present invention. In addition, the charge-discharge control device disclosed herein can be variously modified, and as long as no particular problem occurs, each component and each process mentioned herein can be appropriately omitted or appropriately combined.

Claims

1. A charge and discharge control device controls the charge and discharge of a charge and discharge device that charges and discharges an in-vehicle battery mounted on an electric vehicle. Among them, the charge and discharge device is configured to be able to supply power to a power system and predetermined electrical equipment, the charge and discharge control device includes: a detection unit that detects that the electric vehicle is connected to the charge and discharge device; an SOC acquisition unit that acquires the SOC of the in-vehicle battery of the electric vehicle connected to the charge and discharge device; a usage information acquisition unit that acquires the next usage time and the next driving distance of the electric vehicle connected to the charge and discharge device; a prediction unit that predicts changes in power demand in the power system; and a setting unit that prepares a charge and discharge schedule for the in-vehicle battery of the electric vehicle in such a way that after maintaining the in-vehicle battery at a low SOC, charging is performed, and after supplying predetermined power to the electrical equipment, the SOC required for the next driving distance remains at the next usage time, the SOC after charging is adjusted so that the SOC required for the next driving distance remains after supplying the predetermined power from the in-vehicle battery to the electrical equipment, the setting unit sets the charge and discharge schedule in such a way that the power is supplied to the electrical equipment at a predetermined timing according to the predicted changes in power demand in the power system.

2. The charge and discharge control device according to claim 1, wherein, the low SOC is set to be below the SOC that suppresses deterioration of the in-vehicle battery.

3. The charge and discharge control device according to claim 1 or 2, wherein, the low SOC is set to be above the SOC that can travel a predetermined distance.

4. The charge and discharge control device according to claim 1 or 2, wherein, the charge and discharge control device further includes: a history acquisition unit that acquires the usage history of the electric vehicle; a storage unit that stores the usage history; and a determination unit that determines at least one of the next usage time and the next driving distance according to the stored usage history.

5. The charge and discharge control device according to claim 1 or 2, wherein, the charge and discharge control device further includes: a reservation acquisition unit that acquires the reservation information of the electric vehicle; and a determination unit that determines at least one of the next usage time and the next driving distance according to the reservation information.

6. The charge and discharge control device according to claim 1 or 2, wherein, the charge and discharge control device further includes a demand acquisition unit that acquires changes in power demand in the power system, the setting unit sets the charge and discharge schedule in such a way that when the power demand in the power system is high, the in-vehicle battery discharges to the power system.

7. The charge and discharge control device according to claim 1 or 2, wherein, the charge and discharge control device further includes a demand acquisition unit that acquires changes in power demand in the power system, the setting unit sets the charge and discharge schedule in such a way that when the power demand in the power system is low, the in-vehicle battery is charged from the power system.

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