Vehicle control device

Abstract

To restrain a battery from being deteriorated while reducing loss electric power quantity when charging and discharging.SOLUTION: A vehicle control device comprises: a specification unit which specifies traveling start schedule time at which an electric vehicle starts traveling, the electric vehicle including a battery capable of charging and discharging electric power via a control device between residence and a vehicle; a setting unit which sets, when the time from a present time to the traveling start schedule time is lower than a time threshold value, a value that is larger than a value when the time exceeds the time threshold value, as a first setting value for regulating a lower limit value of a charging rate of the battery when discharging the electric power to the control device; and a transmission unit which sends the first setting value to the control device.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a vehicle control device. [Background technology]

[0002] In recent years, V2H (Vehicle to Home) has been proposed, which allows electric vehicles to be used as a power source for homes. For example, if a home is equipped with a solar power generation system, in V2H, the power generated by the solar power generation system during the day is charged into the battery of the electric vehicle, and the stored power is discharged in the evening to supply it to the home.

[0003] Incidentally, electric vehicles run using electricity stored in a storage battery. Therefore, if the vehicle is scheduled to run the next day, the battery must be discharged in the evening and then recharged before the vehicle is driven. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2013-102608 A [Patent Document 2] JP 2014-239621 A Summary of the Invention [Problem to be solved by the invention]

[0005] When a storage battery is charged and discharged, a certain percentage of the power being charged and discharged is lost due to the resistance of various power conversion devices, wiring, and the storage battery. Repeated charging and discharging of a storage battery can increase the amount of power loss, which can lead to increased environmental and economic burdens. Excessive charging and discharging can also accelerate the deterioration of the storage battery.

[0006] An object of the present invention is to provide a vehicle control device that can suppress deterioration of a storage battery while reducing the amount of power loss during charging and discharging. [Means for solving the problem]

[0007] In order to achieve the above-mentioned object, the vehicle control device of the present invention includes an identification unit that identifies a scheduled start time at which an electric vehicle having a storage battery that can charge and discharge power between a house and a control device will begin traveling, a setting unit that, when the time from the current time to the scheduled start time is below a time threshold, sets a larger value than when the time exceeds the time threshold as a first setting value that specifies a lower limit of the charging rate of the storage battery when discharging power to the control device, and a transmission unit that transmits the first setting value to the control device.

[0008] According to this configuration, when the time from the current time to the scheduled start time of traveling falls below the time threshold, the first set value is set to a large value, so that the amount of discharge when discharging the storage battery is reduced. This also reduces the amount of charge when recharging before traveling, so that the amount of power loss during charging and discharging can be reduced. In addition, excessive charging and discharging is suppressed, so deterioration of the storage battery is suppressed.

[0009] In addition, the storage battery of the vehicle control device according to the present invention generates heat during discharging, and the storage battery of the electric vehicle includes a temperature sensor. When a temperature detection value by the temperature sensor is below a temperature threshold value, the setting unit sets a second setting value that defines an upper limit of a current value during discharging for the control device so that a period during which continuous discharging from the storage battery is possible is longer than when the temperature detection value exceeds the temperature threshold value, and the transmission unit transmits the second setting value to the control device.

[0010] According to this configuration, when the temperature detected by the temperature sensor falls below the temperature threshold value, the second setting value is set so that the discharge time of the storage battery is extended. If the discharge time of the storage battery is extended, the storage battery generates heat for a long period of time, so that when the storage battery is recharged before driving, charging starts in a warm state. This improves the charging efficiency of the storage battery.

[0011] In addition, according to the vehicle control device of the present invention, when the temperature detection value by the temperature sensor is below the temperature threshold value, the setting unit sets the second setting value to a value that is smaller than when the temperature detection value exceeds the temperature threshold value.

[0012] According to this configuration, when the temperature detected by the temperature sensor falls below the temperature threshold value, the second set value is set to a small value. When the current value during discharging becomes small, the time to reach the lower limit charge rate becomes longer, and the discharge time of the storage battery becomes longer. When the discharge time of the storage battery becomes longer, the storage battery generates heat for a long time, and therefore, when recharging before driving, charging begins while the storage battery is warm. This improves the charging efficiency of the storage battery. In addition, excessive charging and discharging is suppressed, and deterioration of the storage battery is suppressed.

[0013] Furthermore, according to the vehicle control device of the present invention, the identification unit identifies a charging start time at which charging for the electric vehicle to run is to start, and when the temperature detection value by the temperature sensor is below a temperature threshold value, the setting unit sets the second setting value based on a value obtained by dividing the difference between the first setting value and the charging rate of the storage battery by the time from the current time to the charging start time.

[0014] With this configuration, when the temperature detected by the temperature sensor falls below the temperature threshold, the battery continues to discharge until just before the charging start time. Because the battery generates heat until just before the charging start time, when the battery is recharged before driving, charging begins while the battery is still warm. This improves the charging efficiency of the battery. Effect of the Invention

[0015] According to the present invention, it is possible to reduce the amount of power loss during charging and discharging and to suppress deterioration of the storage battery. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a block diagram showing a schematic configuration of a power supply system according to an embodiment. [Diagram 2]FIG. 2 is a block diagram showing a schematic configuration of a vehicle according to the embodiment. [Diagram 3] FIG. 3 is a block diagram illustrating an example of a functional configuration of the battery ECU according to the embodiment. [Figure 4] FIG. 4 is a flow diagram illustrating the charge / discharge limit information output process executed in the battery ECU of the embodiment. [Diagram 5] FIG. 5 is a time chart showing an example of the operation of the power supply process when the first setting operation of the embodiment is performed. [Figure 6] FIG. 6 is a time chart showing an example of the operation of the power supply process when the second setting operation of the embodiment is performed. [Figure 7] FIG. 7 is a flow diagram illustrating the operation of calculating the discharge permission current value in the charge / discharge limit information output process executed in the battery ECU of the modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] (Embodiment) Hereinafter, an embodiment of the present invention will be described with reference to Fig. 1 to Fig. 6. Fig. 1 is a block diagram showing a schematic configuration of a power supply system 1 according to an embodiment.

[0018] The power supply system 1 according to the embodiment is a system capable of supplying power stored in a vehicle 4 as power for a house 3. As shown in FIG.

[0019] The V2H system 2 is interposed between the house 3 and the vehicle 4, and controls the exchange of power between the house 3 and the vehicle 4. The V2H system 2 includes a plug 21, and is configured to be connectable to the house 3 and the vehicle 4. The plug 21 is connected to the V2H system 2 by, for example, a connection cable. The V2H system 2 is an example of a control device.

[0020] Specifically, the V2H system 2 acquires electric power from the house 3 and supplies the acquired electric power to the vehicle 4. The V2H system 2 also acquires electric power from the vehicle 4 and supplies the acquired electric power to the house 3. When acquiring electric power from the vehicle 4, the V2H system 2 refers to charge / discharge limit information received from the vehicle 4. The charge / discharge limit information will be described in detail later.

[0021] A house 3 is configured to be capable of receiving and sending electric power to and from a vehicle 4 via a V2H system 2. The house 3 is connected to a solar power generation system 5 and a power grid 6 of an electric company or the like.

[0022] Specifically, the house 3 supplies power generated by a solar power generation system 5 and power supplied from a grid power 6 to load equipment 31 such as electrical appliances, and to the vehicle 4 via the V2H system 2. The house 3 also receives power from the vehicle 4 via the V2H system 2, and supplies the received power to the load equipment 31.

[0023] The vehicle 4 is, for example, an electric vehicle. The vehicle 4 includes a storage battery 41 and a charge / discharge port 42. The vehicle 4 is an example of an electric vehicle.

[0024] The storage battery 41 is configured to be able to charge and discharge power between the house 3 via the V2H system 2. Specifically, the storage battery 41 receives power from the house 3 via the V2H system 2 and charges itself. The storage battery 41 also supplies power to the house 3 via the V2H system 2 by discharging the power. The storage battery 41 may also generate power and charge itself through regenerative operation of the vehicle 4. The power charged in the storage battery 41 is consumed for the vehicle 4 to travel.

[0025] The vehicle 4 is configured so as to be connectable to the plug 21 of the V2H system 2 at the charge / discharge port 42. By connecting the vehicle 4 and the V2H system 2, it becomes possible to exchange electric power between the house 3 and the vehicle 4. Hereinafter, such a process of exchanging electric power between the house 3 and the vehicle 4 may be referred to as a power supply process.

[0026] 2 is a block diagram showing a schematic configuration of a vehicle 4 according to an embodiment. The vehicle 4 includes a battery 43 including a storage battery 41, a drive motor 45, an inverter 46, a vehicle ECU (Electronic Control Unit) 47, a charge management ECU 48, and a communication ECU 49.

[0027] The drive motor 45 is, for example, a three-phase AC motor. The drive motor 45 is driven by power stored in the storage battery 41. That is, the DC power output from the storage battery 41 is boosted by a converter (not shown), and the boosted DC power is converted to AC power by an inverter 46, and the AC power is supplied to the drive motor 45. This causes the drive motor 45 to perform power running. The drive force of the drive motor 45 is transmitted to the wheels via a reduction gear (not shown), causing the vehicle 4 to travel.

[0028] Also, for example, when the vehicle 4 decelerates, and the drive motor 45 is rotated by the wheels, that is, when regenerative operation is performed, the drive motor 45 functions as a generator, converting the generated electricity in the opposite direction to that during driving, and charging the storage battery 41.

[0029] In this embodiment, the vehicle 4 is described as an electric vehicle, but the vehicle 4 may be a hybrid vehicle that uses both an internal combustion engine and a drive motor 45 as drive sources, or selectively uses either of them to run.

[0030] The vehicle ECU 47 is an ECU that performs control related to the body of the vehicle 4. The vehicle ECU 47 acquires detection information from various sensors equipped in the vehicle 4, and controls each part of the vehicle 4 based on the detection information. For example, the vehicle ECU 47 is connected to a temperature sensor 471 equipped in the vehicle 4. The vehicle ECU 47 acquires, for example, an outside air temperature from the temperature sensor 471.

[0031] The charging management ECU 48 is an ECU that manages various settings of the vehicle 4. Specifically, for example, the charging management ECU 48 manages, as reservation information, the air conditioner operation start time input by the driver, the charging start time of the storage battery 41, and the like.

[0032] The communication ECU 49 is an ECU that controls communication within the vehicle 4 and communication outside the vehicle 4. The communication ECU 49 is configured to be able to communicate with an external server 60. The external server 60 provides various information such as map information and weather information, analyzes the driving pattern of the vehicle 4, and provides the analysis results based on the positioning data and driving data of the vehicle 4 acquired from the communication ECU 49.

[0033] Specifically, the communication ECU 49 transmits the positioning data and the driving data to the external server 60 via an in-vehicle transmitter (not shown) and a smartphone or the like carried by the driver. The communication ECU 49 acquires from the external server 60 the current location information of the vehicle 4, weather information of the current location, and information regarding the pattern of the time when the vehicle 4 starts driving.

[0034] The battery 43 includes a storage battery 41 and a battery ECU 44 .

[0035] The storage battery 41 is, for example, a lithium ion battery capable of charging and discharging power. The storage battery 41 is configured as a battery pack in which a plurality of storage batteries 41 (single cells) are connected in series inside. The storage battery 41 generates heat when discharging due to the influence of internal resistance. Furthermore, the charging efficiency of the storage battery 41 decreases when the temperature of the storage battery 41 is low (particularly, when the temperature is lower than 0° C.). In order to increase the charging efficiency, the storage battery 41 may have a heater (not shown) capable of heating the storage battery 41.

[0036] The storage battery 41 also has a current sensor, a voltage sensor, and a temperature sensor, which are not shown. The temperature sensor acquires, for example, the temperature of the storage battery 41 and the outside air temperature as a temperature detection value. The storage battery 41 outputs battery information including the current value, voltage value, and temperature detection value acquired from the various sensors to the battery ECU 44.

[0037] The battery ECU 44 is an ECU that manages the charging and discharging of the storage battery 41. Specifically, the battery ECU 44 generates charge / discharge limit information capable of controlling the charging and discharging of the storage battery 41, based on information acquired from each ECU and battery information acquired from the storage battery 41. The charge / discharge limit information includes information indicating the lower limit charging rate, the permitted discharge current value, and the current charging rate of the storage battery 41. The battery ECU 44 is an example of a vehicle control device.

[0038] The discharge lower limit charging rate is a value that specifies the lower limit of the charging rate of the storage battery 41 during discharging. For example, if the fully charged state of the storage battery 41 is 100% and the completely discharged state is 0%, a discharge lower limit charging rate of 10% means that the storage battery 41 can be discharged until its charging rate reaches 10% of the fully charged state. Therefore, the higher the discharge lower limit charging rate, the less power can be discharged. The discharge lower limit charging rate is an example of a first set value.

[0039] The discharge permitted current value is a value that specifies the upper limit of the current value during discharging. For example, a discharge permitted current value of 0.1 A means that the storage battery 41 can discharge within a range not exceeding 0.1 A. Therefore, the smaller the discharge permitted current value is, the smaller the amount of power discharged per unit time becomes. The discharge permitted current value is an example of a second set value.

[0040] The battery ECU 44 transmits the generated charge / discharge limit information to the V2H system 2. The V2H system 2 obtains power from the storage battery 41 based on the received charge / discharge limit information.

[0041] The schematic configuration of the vehicle 4 shown in Fig. 2 is an example, and does not need to include all of the components shown in Fig. 2, or may include other components. Specifically, for example, the vehicle ECU 47 may have some of the functions of the battery ECU 44, and the battery ECU 44 may have some of the above-mentioned functions of the vehicle ECU 47. Alternatively, the battery ECU 44 and the vehicle ECU 47 may be integrated into one computer.

[0042] Each of the ECUs, such as the battery ECU 44, the vehicle ECU 47, the charge management ECU 48, and the communication ECU 49 described above, includes an arithmetic unit, such as a CPU (Central Processing Unit), and a storage unit, such as a ROM (Read Only Memory). The CPU of each ECU reads and executes a program stored in the ROM to realize various functions.

[0043] Fig. 3 is a block diagram showing an example of a functional configuration of the battery ECU 44 according to the embodiment. As shown in Fig. 3, the battery ECU 44 includes a detection unit 431, a specification unit 432, a setting unit 433, and a transmission unit 434 as functional components.

[0044] The detection unit 431 detects the connection to the V2H system 2. When the detection unit 431 detects the connection to the V2H system 2, the power supply process is started.

[0045] The identifying unit 432 identifies the scheduled start time of the vehicle 4 when the vehicle 4 starts traveling. Specifically, the identifying unit 432 acquires reservation information from the charging management ECU 48. The identifying unit 432 identifies the scheduled start time of the vehicle 4 based on the reservation information. For example, when the air conditioner operation start time is set as "January 1, 12:00" as the reservation information, the identifying unit 432 identifies "January 1, 12:00" as the scheduled start time of the vehicle 4.

[0046] The determination unit 432 also determines a time threshold value and a temperature threshold value. The time threshold value is used in a first setting operation for setting a discharge lower limit charge rate. The temperature threshold value is used in a second setting operation for setting a discharge permitted current value.

[0047] Specifically, for example, the time threshold value and the temperature threshold value are set in advance in a storage unit inside the battery ECU 44 or outside the battery ECU 44. The identification unit 432 identifies the time threshold value and the temperature threshold value by reading the storage unit. The first setting operation and the second setting operation will be described later in detail.

[0048] The setting unit 433 executes a first setting operation and a second setting operation.

[0049] In the first setting operation, the setting unit 433 compares the time from the current time to the scheduled start time with a time threshold value. If the time from the current time to the scheduled start time exceeds the time threshold value, the setting unit 433 sets the first value S1 as the discharge lower limit charging rate. If the time from the current time to the scheduled start time is below the time threshold value, the setting unit 433 sets the second value S2 as the discharge lower limit charging rate. However, the second value S2 is greater than the first value S1.

[0050] However, when the storage battery 41 is charged or discharged, a certain percentage of the charged or discharged power is lost due to various power conversion devices, wiring, and resistance of the storage battery 41 in the power supply system 1. Therefore, repeated charging and discharging of the storage battery 41 may increase the amount of power loss, which may increase the environmental load and the economic load. In addition, excessive charging and discharging may accelerate the deterioration of the storage battery 41.

[0051] As described above, in the first setting operation, when the time from the current time to the scheduled travel start time is below the time threshold value, the setting unit 433 sets the lower limit charge rate of discharge to the second value S2 that is greater than the first value S1. This reduces the amount of power that can be discharged from the storage battery 41. When the amount of discharge is reduced, the amount of charge before the vehicle 4 starts traveling is also reduced, so that the amount of power loss that occurs in the storage battery 41 can be reduced. Furthermore, because the amount of charge and discharge of the storage battery 41 is reduced in this way, deterioration of the storage battery 41 can be suppressed.

[0052] When the time from the current time to the scheduled start time of traveling is equal to the time threshold, the setting unit 433 may set either the first value S1 or the second value S2 as the discharge lower limit charge rate. As an example, when the time from the current time to the scheduled start time of traveling is equal to the time threshold, the setting unit 433 sets the first value S1 as the discharge lower limit charge rate.

[0053] In the second setting operation, the setting unit 433 compares the temperature detection value included in the battery information output from the storage battery 41 with the second threshold value. When the temperature detection value is below the temperature threshold value, the setting unit 433 sets the discharge permission current value so that the time during which continuous discharge from the storage battery 41 is possible is longer than when the temperature detection value is above the temperature threshold value.

[0054] Specifically, when the temperature detection value is above the temperature threshold value, the setting unit 433 sets the first value A1 as the discharge permitted current value. When the temperature detection value is below the temperature threshold value, the setting unit 433 sets the second value A2 as the discharge permitted current value. However, the second value A2 is smaller than the first value A1. In this embodiment, the temperature threshold value is, for example, 0°C. For example, when the outside air temperature is below 0°C, the setting unit 433 sets the discharge permitted current value to the second value A2, which is smaller than the first value A1.

[0055] As described above, the charging efficiency of the storage battery 41 decreases when the temperature is low. In order to increase the charging efficiency, it is desirable to start charging the storage battery 41 when the storage battery 41 is warmed. Furthermore, the storage battery 41 generates heat when it is discharged.

[0056] In the second setting operation, when the temperature detection value is below the temperature threshold value, the setting unit 433 sets the discharge permission current value to a second value A2 smaller than the first value A1. This reduces the amount of power discharged per unit time, and the time during which the storage battery 41 can be continuously discharged becomes longer. When the discharge time becomes longer, the storage battery 41 generates heat for a long time, and therefore charging can be started in a warm state. This improves the charging efficiency of the storage battery 41.

[0057] When the temperature detection value is equal to the temperature threshold value, the setting unit 433 may set either the first value A1 or the second value A2 as the discharge permitted current value. As an example, when the temperature detection value is equal to the temperature threshold value, the setting unit 433 sets the first value A1 as the discharge permitted current value.

[0058] The transmission unit 434 transmits to the V2H system 2 the charge / discharge limit information including the discharge lower limit charge rate and the discharge permitted current value set by the setting unit 433.

[0059] Such charge / discharge limit information is output to the V2H system 2 to control charging / discharging of the storage battery 41. Hereinafter, the process of outputting charge / discharge limit information executed in the battery ECU 44 may be referred to as a charge / discharge limit information output process.

[0060] Fig. 4 is a flow diagram illustrating the charge / discharge limit information output process executed in the battery ECU 44 according to the embodiment. The charge / discharge limit information output process in Fig. 4 is performed as part of the power supply process.

[0061] The detection unit 431 detects a connection to the V2H system 2 (S101). This starts the discharge limit information output process.

[0062] Next, the identifying unit 432 identifies the scheduled travel start time of the vehicle 4 (S102).

[0063] Next, the identification unit 432 identifies a time threshold value and a temperature threshold value (S103).

[0064] Next, the setting unit 433 determines whether the time from the current time to the scheduled start time of traveling is below the time threshold value (S104). If the time from the current time to the scheduled start time of traveling is not below the time threshold value (S104: No), that is, if the time is equal to or greater than the time threshold value, the setting unit 433 sets the first value S1 as the discharge lower limit charging rate (S105). If the time from the current time to the scheduled start time of traveling is below the time threshold value (S104: Yes), the setting unit 433 sets the second value S2 (where S2>S1) as the discharge lower limit charging rate (S106). The processes of S104 to S106 correspond to a first setting operation.

[0065] Next, the transmitter 434 transmits the discharge lower limit charge rate to the V2H system 2 (S107).

[0066] Next, the setting unit 433 determines whether or not the temperature detection value is below the temperature threshold value (S108). If the temperature detection value is not below the temperature threshold value (S108: No), that is, if the temperature detection value is equal to or greater than the temperature threshold value, the setting unit 433 sets the first value A1 as the discharge permitted current value (S109). If the temperature detection value is below the temperature threshold value (S108: Yes), the setting unit 433 sets the second value A2 (where A1>A2) as the discharge permitted current value (S110). The processes of S108 to S110 correspond to a second setting operation.

[0067] Next, the transmission unit 434 transmits the discharge permission current value to the V2H system 2 (S111). In addition, the transmission unit 434 transmits the current charging rate of the storage battery 41 to the V2H system 2 (S112).

[0068] The operation of transmitting the charging rate in step S112 may be executed only when connected to the V2H system 2 as illustrated in Fig. 4. Alternatively, the operation of transmitting the charging rate may be executed repeatedly and updated over time by the repeated execution.

[0069] The charge / discharge limit information output process is completed by the above process. The V2H system 2 obtains power from the storage battery 41 based on the charge / discharge limit information so that the charge rate of the storage battery 41 does not fall below the lower limit charge rate and so that the discharge current value during discharge of the storage battery 41 does not exceed the permitted discharge current value.

[0070] Next, an example of the power supply process when the first setting operation and the second setting operation are performed will be described with reference to FIGS.

[0071] FIG. 5 is a time chart showing an example of the operation of the power supply process when the first setting operation of the embodiment is performed.

[0072] The horizontal axis of Fig. 5 represents time. The vertical axis (left) of Fig. 5 represents the charging rate (%) of the storage battery 41, and the vertical axis (right) represents the discharge current value (A). Note that Fig. 5 is a simplified depiction of the main points of the time changes of each quantity, and there may be some parts that differ from the actual time changes.

[0073] 5, the lower limit charging rate of the storage battery 41 is set to a first value S1 as an initial state at time t0. The charging rate of the storage battery 41 in a fully charged state is set to a third value S3, and the storage battery 41 is charged to the fully charged state at the scheduled start time of the vehicle 4. The scheduled start time of the vehicle 4 is time t5. The permitted discharge current of the storage battery 41 is fixed to a first value A1.

[0074] At time t0, a connection between the V2H system 2 and the vehicle 4 is detected, and the power supply process starts.

[0075] At time t1, if the time from time t1 to time t5 is less than the time threshold value, the setting unit 433 changes the discharge lower limit charge rate from a first value S1 to a second value S2 (where S2>S1). When the charge / discharge limit information including the discharge lower limit charge rate is transmitted to the V2H system 2, the V2H system 2 starts obtaining power and the storage battery 41 starts discharging.

[0076] At time t2, when the charging rate of the storage battery 41 reaches the second value S2 from the third value S3, discharging of the storage battery 41 ends. The discharge amount at this time is the difference between the third value S3 and the second value S2. The discharge time is the difference between time t2 and time t1.

[0077] At time t3, charging of the storage battery 41 starts. Time t3 is a time after discharging of the storage battery 41 ends at time t2 and before the scheduled travel start time. Time t3 may be determined based on the scheduled travel start time, for example, or may be determined in advance by the charge management ECU 48.

[0078] At time t4, when the charging rate of the storage battery 41 reaches the third value S3 from the second value S2, charging of the storage battery 41 is completed. The charging amount is the difference between the third value S3 and the second value S2.

[0079] At time t5, the vehicle 4 starts traveling. This is the end of the power supply process.

[0080] FIG. 6 is a time chart showing an example of the operation of the power supply process when the second setting operation of the embodiment is performed.

[0081] The horizontal axis of Fig. 6 represents time. The vertical axis (left) of Fig. 6 represents the charging rate (%) of the storage battery 41, and the vertical axis (right) represents the discharge current value (A). Note that Fig. 6 is a simplified depiction of the gist of the time changes of each quantity, and there may be some parts that differ from the actual time changes. Also, explanations of parts common to Fig. 5 will be omitted as appropriate.

[0082] 6, in the initial state at time t0, the discharge permitted current value of the storage battery 41 is set to a first value A1, and the discharge lower limit charge rate is fixed to a first value S1.

[0083] At time t0, the power supply process begins.

[0084] At time t1, if the detected temperature value is below the temperature threshold value, the setting unit 433 changes the discharge permitted current value from the first value A1 to a second value A2 (where A1>A2). When the charge / discharge limit information including the discharge permitted current value is transmitted to the V2H system 2, the V2H system 2 starts obtaining electric power and the storage battery 41 starts discharging.

[0085] At time t6, when the charging rate of the storage battery 41 reaches the second value S2 from the third value S3, discharging of the storage battery 41 ends. The discharge time is the difference between time t6 and time t1. Time t6 is later than time t2 in FIG. 5, which shows the discharge end time when the discharge permitted current value is the first value A1. In this way, the discharge permitted current value is changed to the second value A2, which is smaller than the first value A1, so that the discharge time of the storage battery 41 becomes longer.

[0086] At time t3 in FIG. 6, charging of the storage battery 41 begins.

[0087] At time t4 in FIG. 6, when the charging rate of the storage battery 41 reaches the third value S3 from the second value S2, charging of the storage battery 41 ends.

[0088] (Overview) When the time from the current time to the scheduled travel start time is below the time threshold, the battery ECU 44 of the embodiment sets the discharge lower limit charge rate to a value greater than when the time exceeds the time threshold.

[0089] This reduces the amount of charge and discharge of the storage battery 41, thereby reducing the amount of power loss of the storage battery 41. In addition, excessive charge and discharge are suppressed, so deterioration of the storage battery 41 is suppressed.

[0090] Furthermore, when the temperature detection value is below the temperature threshold value, the battery ECU 44 in the embodiment sets the discharge permitted current value so that the time during which continuous discharge from the storage battery 41 is possible is longer than when the temperature detection value exceeds the temperature threshold value. Specifically, the battery ECU 44 sets the discharge permitted current value to a smaller value than when the temperature detection value exceeds the temperature threshold value.

[0091] This reduces the amount of power discharged per unit time, and therefore the time during which the storage battery 41 can be continuously discharged becomes longer. As the discharge time becomes longer, the storage battery 41 generates heat for a longer period of time, and therefore charging of the storage battery 41 begins in a warm state. As a result, the charging efficiency of the storage battery 41 improves. Moreover, excessive charging and discharging is suppressed, and deterioration of the storage battery 41 is suppressed. Furthermore, if a heater for warming the storage battery 41 is installed, the time for heating by the heater can be shortened.

[0092] (Modification) Next, a modified example will be described with reference to Fig. 7. The battery ECU 44 of the modified example is different from the above-mentioned embodiment in that it calculates and sets the discharge permission current value. Note that, in the modified example, descriptions of parts common to the above-mentioned embodiment will be omitted as appropriate.

[0093] Fig. 7 is a flow diagram illustrating the operation of calculating a discharge permission current value in the charge / discharge limit information output process executed in the battery ECU 44 of the modified example. The series of flows shown in Fig. 7 is executed in place of the process of S110 described in Fig. 4. Therefore, it is assumed that the processes corresponding to the processes of steps S101 to S108 in Fig. 6 are executed prior to the process of step S201 in Fig. 7.

[0094] When the setting unit 433 determines that the temperature detection value is below the temperature threshold value, the identifying unit 432 identifies the charging start time at which charging for traveling of the vehicle 4 is to start (S201). Specifically, the identifying unit 432 acquires reservation information from the charging management ECU 48, and identifies the charging start time of the vehicle 4 based on the reservation information. For example, when the charging start time is set as "February 1st, 00:00" as the reservation information, the identifying unit 432 identifies "February 1st, 00:00" as the charging start time of the vehicle 4.

[0095] Next, the setting unit 433 acquires the discharge lower limit charge rate (S202). The discharge lower limit charge rate is set in a step corresponding to step S105 or step S106 in FIG.

[0096] Next, the setting unit 433 acquires the current charging rate of the storage battery 41 (S203). The current charging rate of the storage battery 41 is calculated based on the battery information output from the storage battery 41.

[0097] Next, the setting unit 433 calculates the discharge permission current value based on the current charging rate of the storage battery 41, the discharge lower limit charging rate, and the time from the current time to the charging start time (S204). Specifically, the setting unit 433 calculates the discharge permission current value based on a value obtained by dividing the difference between the discharge lower limit charging rate and the current charging rate by the time from the current time to the charging start time.

[0098] Following the process of step S204, processes corresponding to the processes of steps 111 to S112 in Fig. 4 are executed. Through the above processes, the charge / discharge limit information output process of the modified example is completed. This allows the storage battery 41 to continue discharging until just before the charging start time.

[0099] 7 may be executed only immediately after connection to the V2H system 2. Alternatively, the series of operations in the flow of Fig. 7 may be executed repeatedly, and the discharge permitted current value may be updated successively over time by the repeated execution. The battery ECU 44 may transmit the updated discharge permitted current value to the V2H system 2 every time the battery ECU 44 updates the discharge permitted current value.

[0100] Therefore, for example, when the amount of power usage in the load equipment 31 of the house 3 is low and the rate at which the charge rate of the storage battery 41 decreases is slower than the rate of decrease corresponding to the permitted discharge current value, the battery ECU 44 may change the permitted discharge current value to a larger value.

[0101] (Other Examples) In the above-described embodiment and modified example, the determination unit 432 determines the scheduled driving start time based on the air conditioner operation start time obtained from the charging management ECU 48, but the method of determining the scheduled driving start time is not limited to this method.

[0102] For example, the identifying unit 432 may identify the scheduled travel start time based on the charging start time of the storage battery 41 acquired from the charging management ECU 48. Specifically, the identifying unit 432 may predict the charging end time from the charging start time, and identify the predicted charging end time as the scheduled travel start time.

[0103] Further, for example, the identification unit 432 may identify the scheduled travel start time based on the analysis result of the travel pattern of the vehicle 4 acquired from the communication ECU 49. Specifically, the identification unit 432 may identify the scheduled travel start time of the vehicle 4 based on a pattern of the time when the vehicle 4 starts traveling.

[0104] In the above-described embodiment and modified examples, the time threshold value is set in advance in a memory unit such as the battery ECU 44, and the determination unit 432 determines the time threshold value by reading the memory unit, but the method of determining the time threshold value is not limited to this method.

[0105] Specifically, the determination unit 432 may determine whether or not power generation is possible in the photovoltaic power generation system 5 based on weather information, and may determine the time threshold value so that the longer the time during which power generation is not possible, the larger the time threshold value. In the above-described embodiment and modified examples, the time threshold value is, for example, 24 hours. If the weather on the next day is rainy, the determination unit 432 may determine the time threshold value to be 48 hours, which is longer than 24 hours, and if the weather is rainy until the day after that, the determination unit 432 may determine the time threshold value to be 72 hours, which is even longer. Note that the method by which the determination unit 432 acquires weather information is not limited to a certain method. For example, the determination unit 432 may acquire weather information via the communication ECU 49.

[0106] In this way, when power generation by the solar power generation system 5 is not expected, that is, when charging of the storage battery 41 is not expected for a long time, the time threshold value is increased so that the time from the current time to the scheduled travel start time can easily fall below the time threshold value. This makes it easier to set a large value as the discharge lower limit charge rate, so that the vehicle 4 can travel with a small amount of charge.

[0107] Although the embodiment and the modified examples of the present invention have been described above, the above-mentioned embodiment and the modified examples are presented as examples and are not intended to limit the scope of the present invention. The new embodiment and the modified examples can be implemented in various other forms. In addition, various omissions, substitutions, and modifications can be made without departing from the gist of the invention. In addition, the embodiment and the modified examples are included in the scope and gist of the invention, and are included in the scope of the invention and its equivalents described in the claims. [Explanation of symbols]

[0108] 1 Power supply system, 2 V2H system, 3 House, 4 Vehicle, 5 Solar power generation system, 6 Power grid, 21 Plug, 31 Load equipment, 41 Storage battery, 42 Charging / discharging port, 43 Battery, 44 Battery ECU, 45 Drive motor, 46 Inverter, 47 Vehicle ECU, 48 Charging management ECU, 49 Communication ECU, 431 Detection unit, 432 Identification unit, 433 Setting unit, 434 Transmission unit.

Claims

1. an identification unit that identifies a scheduled travel start time when an electric vehicle having a storage battery that can charge and discharge power between the house and the electric vehicle via a control device will start traveling; a setting unit that sets a first setting value that specifies a lower limit of a charging rate of the storage battery when discharging power to the control device, when a time from a current time to the scheduled travel start time is below a time threshold value, to a value that is larger than a value when the time exceeds the time threshold value; A transmission unit that transmits the first setting value to the control device; Equipped with Vehicle control device.

2. The battery of the electric vehicle is equipped with a temperature sensor, the setting unit sets a second setting value that defines an upper limit of a current value during discharging for the control device so that a time during which continuous discharging from the storage battery is possible is longer when a temperature detection value by the temperature sensor is below a temperature threshold value compared to when the temperature detection value exceeds the temperature threshold value; The transmission unit transmits the second setting value to the control device. The vehicle control device according to claim 1.

3. The setting unit is when the temperature detection value by the temperature sensor is below a temperature threshold value, a value smaller than that when the temperature detection value exceeds the temperature threshold value is set as the second setting value. The vehicle control device according to claim 2.

4. The identification unit is identifying a charging start time at which charging for running the electric vehicle is to start; The setting unit is When the temperature detection value by the temperature sensor falls below the temperature threshold value, the second set value is set based on a value obtained by dividing a difference between the first set value and the charging rate of the storage battery by a time from a current time to the charging start time. The vehicle control device according to claim 2.

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