Electric vehicle control device, electric vehicle and control method thereof

Abstract

The invention provides an electric vehicle control apparatus, an electric vehicle and a control method thereof. In an electric vehicle that travels using an electric power input / output battery, whether the driving mode of the vehicle is a first driving mode in which the degree of intervention of a driver with respect to vehicle travel is low or a second driving mode in which the degree of intervention of the driver with respect to vehicle travel is higher than the first driving mode is determined. When it is determined that the driving mode is the first driving mode, the upper limit of the amount of electricity per unit time with respect to the entry and exit of the battery is set to a first upper limit amount that is lower than a second upper limit amount that is the upper limit set in the second driving mode. On the basis of this, the amount of electric power to enter and exit from the storage battery is controlled within a range that does not exceed a first upper limit or a second upper limit set in accordance with the driving mode.

Description

Technical Field

[0001] The present disclosure relates to an electric vehicle control device equipped with a storage battery, an electric vehicle, and a control method thereof. Background Art

[0002] In battery-equipped vehicles, technologies for suppressing the reduction of battery life have been proposed. For example, Japanese Patent Application Laid-Open No. 2012-120372 discloses a technology that uses a battery including a plurality of cells, switches the cell connected to a load, and relaxes the output restriction of the battery when a predetermined condition is met. Summary of the invention

[0003] However, in the case of wanting to suppress the reduction in the life of the battery, it becomes a problem to consider what kind of driving mode to use when driving a vehicle equipped with the battery. The reason is that, depending on the driving mode, there are different possibilities such as the output requirement for the battery when the motor is driven by the electricity stored in the battery, and the input requirement for the battery when the battery is charged with regenerative power. In a vehicle running on such a battery, as driving modes that may affect the life of the battery, for example, an automatic cruise driving mode with automatic cruise turned on, a following driving mode that follows the vehicle in front, an automatic driving mode that does not assume the intervention of the driver, and a normal driving mode driven by the driver (hereinafter referred to as manual mode), etc. There is still room for research on suppressing the reduction in battery life based on such driving modes.

[0004] The present disclosure can be implemented in the following forms or application examples.

[0005] (1) A first aspect of the present disclosure provides an electric vehicle control device, the electric vehicle running using a storage battery that inputs and outputs electric power, wherein the electric vehicle control device includes:

[0006] a driving mode determination unit for determining whether the driving mode of the vehicle is a first driving mode which is one of two driving modes having different degrees of intervention by the driver in the travel of the vehicle, and a second driving mode in which the degree of intervention by the driver is higher than that of the first driving mode;

[0007] an upper limit setting unit that sets an upper limit on the amount of electricity per unit time input and output from the battery to a first upper limit amount that is lower than a second upper limit amount that is an upper limit set in the second driving mode, when it is determined that the driving mode is the first driving mode; and

[0008] The battery control unit controls the amount of electricity input and output to and from the battery in a range not exceeding the first upper limit or the second upper limit according to the driving mode.

[0009] As a result, the upper limit of the amount of electricity input and output from the battery in the first driving mode, i.e., in a state closer to the automatic driving side, where the driver's intervention in the vehicle driving is low, can be lower than the upper limit of the amount of electricity input and output from the battery in the second driving mode, i.e., in a state closer to the automatic driving side, thereby suppressing the temperature rise of the battery. As a result, the battery life can be extended.

[0010] (2) In the electric vehicle control device according to the above aspect, it is also possible to

[0011] The upper limit setting unit:

[0012] As the upper limit of the electric quantity, an upper limit of at least one of the charge amount and the discharge amount of the battery is set.

[0013] A charge variation width, which is a variation width from the second upper limit to the first upper limit of the charge amount, is smaller than a discharge variation width, which is a variation width from the second upper limit to the first upper limit of the discharge amount.

[0014] The temperature of the battery, which affects the life of the battery, depends on the internal resistance of the battery and the current flowing in and out. Therefore, although it makes sense to limit the upper limit during charging and discharging, it is assumed that the battery is charged when the vehicle decelerates and utilizes the regenerative braking provided by the electric motor. Therefore, when the charging variation range is made smaller than the discharging variation range, the constraints of regenerative braking can be reduced, making it difficult to affect the vehicle's drivability, etc.

[0015] (3) In the electric vehicle control device according to each of the above-mentioned aspects, it is also possible to

[0016] The charging variation amplitude is zero.

[0017] As a result, the amount of electricity input to the battery is not limited, and the influence on drivability can be minimized.

[0018] (4) In the electric vehicle control device according to each of the above-mentioned aspects, it is also possible to

[0019] A detection unit is provided for detecting the usage condition of the battery,

[0020] The upper limit setting unit further reduces the first upper limit amount when it is determined that the detected usage condition meets a condition predetermined as a usage condition that may reduce the life of the storage battery.

[0021] This can further suppress reduction in the life of the battery.

[0022] (5) In the electric vehicle control device according to each of the above-mentioned aspects, it is also possible to

[0023] The usage condition includes at least one of a temperature of the battery and a cumulative usage time. The predetermined condition is that the temperature of the battery is higher than a predetermined temperature and the cumulative usage time of the battery is higher than a predetermined cumulative time.

[0024] The battery temperature and the accumulated usage time have a high correlation with the battery life. Therefore, if at least one of them is detected and the first upper limit is lowered, the battery life can be further extended.

[0025] (6) In the electric vehicle control device according to each of the above-mentioned aspects, it is also possible to

[0026] The vehicle is a battery-electric vehicle that runs on the power of the battery.

[0027] By limiting the maximum speed of the vehicle, the discharge amount of the battery is limited.

[0028] This makes it possible to limit the speed of the vehicle, prevent an excessive load from being placed on the battery, and further extend the life of the battery.

[0029] (7) In the electric vehicle control device according to each of the above-mentioned aspects, it is also possible to

[0030] further comprising a switch that can be set by an occupant of the vehicle,

[0031] The battery control unit causes the speed control unit to limit the maximum speed when the driving mode of the vehicle is the first driving mode and the switch is set to on.

[0032] This makes it possible to further extend the life of the battery in accordance with the wishes of the occupant.

[0033] (8) In the electric vehicle control device according to each of the above-mentioned aspects, it is also possible to

[0034] The first driving mode is an automatic driving mode in which the vehicle is driven without intervention of the driver, and the second driving mode is a manual driving mode in which the vehicle is driven with intervention of the driver.

[0035] As a result, the vehicle can travel automatically without intervention by the driver, so that priority can be given to extending the life of the battery.

[0036] (9) The present disclosure includes not only the above-mentioned electric vehicle control device, but also a method of an electric vehicle having each component of such an electric vehicle control device and a method of controlling the electric vehicle. In any of the methods, by controlling an inverter that exchanges power between a battery and an electric motor, it is possible to extend the life of the battery in the first driving mode in which the degree of driver intervention in vehicle driving is lower than that in the second driving mode. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, in which like reference numerals represent like elements, and in which:

[0038] Figure 1 : is a schematic structural diagram of a vehicle used in each embodiment.

[0039] Figure 2 It is an explanatory diagram showing the configuration of an electrical system in each embodiment.

[0040] Figure 3 This is a flowchart showing an overview of the electric power limitation processing routine in the first embodiment.

[0041] Figure 4 This is an explanatory diagram illustrating the relationship between the level of automatic driving and the power control in the first embodiment.

[0042] Figure 5 2 is an explanatory diagram showing an example of limitation of electric power in a similar manner.

[0043] Figure 6 This is a flowchart showing an overview of the electric power limitation processing routine in the second embodiment.

[0044] Figure 7 This is an explanatory diagram illustrating the relationship between the level of automatic driving and power control in the second embodiment.

[0045] Figure 8 2 is an explanatory diagram showing an example of limitation of electric power in a similar manner.

[0046] Fig. 9 : is a flowchart showing another configuration example of the power limit processing routine. DETAILED DESCRIPTION

[0047] A. First Implementation Method:

[0048] (A1) Vehicle structure:

[0049] The electric vehicle control device of the first embodiment is embedded in the vehicle AM, so the structure of the vehicle AM ​​is first described. The vehicle AM ​​can perform multiple levels of automatic driving independently of the usual driving (manual driving) performed by the driver. Specifically, the vehicle AM ​​includes manual driving (level 0) and can achieve the level of automatic driving (0 to 5). Such automatic driving is realized by the electric vehicle control device 200. The electric vehicle control device 200 is equipped with an automatic driving ECU 100 that realizes automatic driving under the specified level 4 or 5 according to the path indication from the path guidance device 110 that guides the path to the destination. Originally, in addition to the steering wheel 151, the vehicle AM ​​is also provided with an accelerator pedal, a brake pedal, etc. that are not shown in the figure, and the driver can also drive (level 0), or drive with driving assistance (levels 1 to 2), or intervene in the automatic driving controlled by the automatic driving ECU 100 (level 3). In addition, the part that undertakes such automatic driving can also be made independent as a vehicle driving device, and only the part that controls the charging and discharging of the battery described later in the electric vehicle is constituted as an electric vehicle control device.

[0050] The electric vehicle control device 200 includes a large number of devices, such as a power control ECU 120, a motor 130, a steering ECU 140, and a steering device 150, in addition to the above-mentioned automatic driving ECU 100 and the route guidance device 110. These ECUs and devices are connected via a network CAN, which is an in-vehicle LAN not shown in the figure, and always exchange data and commands. An indication unit 105 having a switch for setting the level of automatic driving and a protection switch 106 for setting the on / off of the protection mode described later is connected to the automatic driving ECU 100. The indication unit 105 can be set on an instrument panel, etc., or it can be configured as a wireless terminal to send instructions to the automatic driving ECU 100 via the wirelessly connected network CAN.

[0051] The power control ECU 120 controls the driving force and braking force for driving the vehicle AM. The driving force ECU 120 receives instructions from the automatic driving ECU 100 to control the driving power of the driving motor 130 and the regenerative power during braking. The motor 130 exchanges power with the battery pack 40 described later via a power control unit (hereinafter referred to as PCU) having an inverter. The power control ECU 120 directly controls the inverter. The electrical system such as the inverter will be summarized later. The driving force when the motor 130 receives power supply and rotates is transmitted to the left and right rear wheels 11 and 12 via a gearbox 132 including a differential gear and a drive shaft 134. In the present embodiment, it is set as rear-wheel drive, but it can also be front-wheel drive, or it can be four-wheel drive. The vehicle AM ​​of the first embodiment has a structure as a so-called battery electric vehicle.

[0052] The steering device 150 includes an encoder 152 for detecting the steering amount (rotation angle) of the steering wheel 151, and a steering motor 154 for driving a steering gear 155. The steering motor 154 of the steering device 150 controls the steering angle (angle relative to the straight line in the forward direction) of the right and left front wheels 13 and 14 via the steering gear 155. The steering gear 155 provides a necessary turning radius to each of the steering angles of the right and left front wheels 13 and 14.

[0053] Next, the structure for applying braking force from each wheel 11 to 14 is described. As described above, the rear wheels 11 and 12 obtain braking force by regenerating electric power through the motor 130, but the rear wheels 11 and 12 are provided with a structure that can apply braking force to each wheel 11 to 14 by hydraulic pressure. Figure 1 As shown, a disc brake device including a brake disc BD, a wheel cylinder 19 to 22, etc. is provided on the wheels 11 to 14, and the braking force of each wheel can be controlled by using the hydraulic pressure supplied through the hydraulic piping system 10. The brake disc BD provided on each wheel 11 to 14 is sandwiched by a disk pad (not shown) additionally provided on the wheel cylinder 19 to 22, and the braking force is generated by the friction between the disk pad and the brake disc. The electric vehicle control device 200 is configured to calculate the braking force required for the vehicle AM ​​during automatic driving. When the braking force obtained by using the regenerative power of the electric motor 130 is sufficient, the regenerative braking is prioritized. When the braking force is insufficient under the regenerative braking, the brake disc BD is used to compensate for the insufficient braking force. The hydraulic pressure of the wheel cylinders 19 to 22 driven to obtain the necessary braking force is controlled by the power control ECU 120.

[0054] (A2) Electrical structure:

[0055] Figure 2 1 is an explanatory diagram showing an electrical system in a vehicle AM. As shown in the figure, the vehicle AM ​​includes a power control unit (hereinafter referred to as PCU) 30 for controlling power input and output with a motor 130, a battery pack 40 for storing power, an auxiliary device battery 55 for supplying DC power to a DC auxiliary device 57 operating in DC, and an auxiliary device inverter 62 for supplying AC power to an AC auxiliary device 65 operating in AC.

[0056] The battery pack 40 includes a main storage battery 41 as a secondary battery, an ACR 45 for controlling a charging current, a system main relay (hereinafter referred to as SMR) 47, etc. The ACR 45 is connected to an external AC charger 51. The main storage battery 41 of the present embodiment is formed by connecting a large number of battery cells in series (n) and then connecting m of them in parallel. Therefore, the internal resistance r of the main storage battery 41 is obtained as the sum of the series and parallel internal resistances R of each battery cell by the following formula (1).

[0057] r=(R×n) / m…(1)

[0058] The amount of heat CJ generated inside the main battery 41 is proportional to the square of the current I output to or input to the main battery 41 as shown in the following equation (2).

[0059] CJ=r×I 2 …(2)

[0060] The AC charger 51 is connected to a charging connector 52 connected to an external AC power source, and when the AC power source is connected to the charging connector 52, the main battery 41 is charged via the ACR 45. Here, the charging is described as using an AC power source, but a DC charger may be prepared and connected to an external DC power source to charge the main battery 41 via the DCR. The energy required for the vehicle AM ​​to travel and various electrical machines is basically based on the power stored in the main battery 41 of the battery pack 40. The SMR 47 is inserted into the output path from the main battery 41 to turn the main current on / off. When the IG switch not shown is turned on, the SMR 47 is turned on (connected state), and the DC current from the battery pack 40 is supplied to the PCU 30, etc. The path connecting the main battery 41 and the PCU 30 via the SMR 47 is sometimes referred to as the main power line MPL.

[0061] The PCU 30 is internally provided with an inverter 32 and a DC-DC converter (hereinafter referred to as DDC) 35. The inverter 32 operates in response to an instruction from the power control ECU 120 included in the electric vehicle control device 200. The power control ECU 120 controls the inverter 32 to supply the DC power received from the battery pack 40 via the main power line MPL as a three-phase AC to the motor 130, thereby driving the vehicle AM. On the other hand, during braking, the power regenerated by the motor 130 is converted into DC and supplied to the battery pack 40 via the main power line MPL to charge it. The auxiliary equipment battery 55, which is another secondary battery provided in the vehicle AM, functions as a DC power supply for operating various ECUs and the DC auxiliary equipment 57 included in the electric vehicle control device 200. The auxiliary equipment battery 55 is connected to the main power line MPL via the DDC 35, and when the charge level of the auxiliary equipment battery 55 is reduced, it is charged via the DDC 35.

[0062] (A3)Battery control:

[0063] Next, use Figure 3, explaining the power control processing in the battery pack 40. The illustrated power control processing routine shows an example of a process performed by the power control ECU 120 exchanging information with the automatic driving ECU 100. After starting the operation, the power control ECU 120 repeatedly executes the power control process. The power control ECU 120 first communicates with the automatic driving ECU 100 to obtain the driving mode process (S111). The driving mode refers to the mode of automatic driving performed by the automatic driving ECU 100, which is generally represented by levels 0 to 5. In addition, in the case of non-automatic driving, that is, manual driving, the power control ECU 120 obtains a value from the automatic driving ECU 100 indicating that the driving mode is manual driving.

[0064] Next, it is determined whether the obtained driving mode is the first driving mode or the second driving mode (S112). This process is equivalent to the driving mode determination unit. Here, the first driving mode refers to a driving mode in which the driver's intervention level for the vehicle driving is low, and the second driving mode refers to a driving mode in which the driver's intervention level is higher than that of the first driving mode. That is, it means that the first driving mode has a higher level of automatic driving than the second driving mode. In this embodiment, the level 4 or 5 of automatic driving is set as the first driving mode, and the level 3 or less of automatic driving is set as the second driving mode, but the distinction between the two can also be set other than that. For example, the level 3 or more of automatic driving can also be set as the first driving mode, and the level 5 or more can also be set as the first driving mode. Regarding the determination of the driving mode, a threshold value can also be predetermined, and the determination can be made by judging the size of the threshold value. For example, any level from level 0 to 2 can also be set as a threshold value, and the level above it can be set as the first driving mode. In addition, level 0 means that the automatic driving ECU 100 does not intervene in the driver's driving of its own state at all, that is, the manual driving mode.

[0065] If the first driving mode is determined in S112, the upper limit of the amount of electricity input to and output from the main battery 41 of the battery pack 40 is set to the first upper limit (S121). On the other hand, if the second driving mode is determined in S112, the upper limit of the amount of electricity input to and output from the main battery 41 of the battery pack 40 is set to the second upper limit (S122). These processes correspond to the upper limit setting unit. Figure 41 shows a combination of upper limits set in the present embodiment. As shown in the figure, if the driving mode is the first driving mode, that is, the level 3 or higher of the automatic driving, the upper limit of the output power Wout taken out from the main battery 41 is set to the first upper limit OL1. In addition, if the driving mode is the second driving mode, that is, the level 2 or lower of the automatic driving, the upper limit of the output power Wout taken out from the main battery 41 is set to the default setting value, that is, the second upper limit OL2. In addition, the upper limit of the input power Win input to the main battery 41, that is, used for charging, is maintained as is the second upper limit IL2 set by default.

[0066] After executing the upper limit setting process (S121 or S122), the power control ECU 120 performs battery control within the range of the set upper limit (S131). This process corresponds to the battery control unit. Figure 5 , illustrating battery control within the range of the upper limit. Figure 5 The vertical axis shows the amount of electricity input and output relative to the main battery 41 as a storage battery, the upper side of the origin shows the output electricity Wout taken out from the main battery 41, and the lower side shows the input electricity Win used to charge the main battery 41. Here, the amount of electricity can be either the amount of electric power or the amount of current per hour. In the figure, the first upper limit OL1 and the second upper limit OL2 are shown for the output electricity, and the second upper limit IL2 is shown for the input electricity. Here, the second upper limit OL2 on the output side and the second upper limit IL2 on the input side are the default upper limits of the main battery 41, indicating the so-called rated. In contrast, the first upper limit OL1 on the output side, as the upper limit of the amount of electricity input and output relative to the main battery 41, indicates the upper limit set when the driving mode is the first driving mode, that is, when the autonomous driving level is above 3.

[0067] Each upper limit OL1, OL2, IL2 takes a constant value when the vehicle speed V is below a predetermined value. When the vehicle speed V is below a predetermined value, the upper limit OL1 of the electric quantity output from the main battery 41 is the electric quantity Wo1, the upper limit OL2 is the electric quantity Wo2, and the upper limit IL2 input to the main battery 41 is the electric quantity Wi2. The difference between the upper limit on the output side, that is, the electric quantity Wo2 and the electric quantity Wo1 is equivalent to the discharge variation range ΔWo. In addition, if the vehicle speed V is high, the temperature of the main battery 41 rises due to the previous travel of the vehicle AM, so in order to avoid excessive temperature rise, each upper limit OL1, OL2, IL2 has a characteristic of gradually decreasing when the vehicle speed V becomes high.

[0068] The electric vehicle control device 200 of the first embodiment described above can perform manual driving of levels 0 to 2, driving under assisted driving (second driving mode), and automatic driving of levels 3 or higher (first driving mode), and can make the upper limit of the amount of electricity output from the main battery 41 different according to such driving modes, so as to suppress the heating of the main battery 41. In the first driving mode, the automatic driving ECU 100 controls the acceleration of the vehicle AM, so even if the upper limit of the amount of electricity output from the main battery 41 is reduced, it will not cause any hindrance to driving. In the automatic driving mode, no rapid acceleration exceeding a predetermined acceleration is performed, so the upper limit of the amount of electricity output from the main battery 41 can be reduced, and the heating of the main battery 41 can be suppressed, and as a result, the driving life can be extended. Here, the amount of electricity can be an electric power value or a current value, because if the upper limit of the current value I is reduced, the heat generation CJ is suppressed as shown in the above formula (2). In addition, the upper limit of the amount of electricity can be limited as an electric power value, or the amount of electricity can be limited by limiting the number of battery cells used in the main battery 41 in which a large number of battery cells are connected in series and parallel. In this case, if the combination of battery cells used is changed, the average operation rate per battery cell is reduced, which contributes to a longer life.

[0069] B. Second Implementation Method:

[0070] Next, an electric vehicle control device 200 and a vehicle AM ​​equipped with the same according to a second embodiment will be described. The hardware configuration of the electric vehicle control device 200 and the vehicle AM ​​according to the second embodiment is substantially the same as that of the first embodiment. In the second embodiment, the content of the power limit processing is different. Figure 6 The outline of the electric power limit processing routine in the second embodiment is shown. The illustrated routine is different from the first embodiment in that S125 to S127 are added between S121 and S131.

[0071] The power limit processing routine starts, and similarly to the first embodiment, the first upper limit or the second upper limit is set according to the acquired driving mode (S111, S112), and then the vehicle speed V is obtained from the automatic driving ECU 100 (S125). Next, the state of the protection switch 106 provided in the indicator 105 is read (S126), and if the protection switch 106 is turned on (S126: Yes), the vehicle speed limit is added to the first upper limit of the power output from the main battery 41 (S127). On this basis, the power input and output to the main battery 41 is controlled according to the set limit (S131).

[0072] Figure 7 The relationship between the level of autonomous driving and power control in the second embodiment is shown, and Figure 8 An example of the control of the amount of electricity in this case is shown below. Figure 7 As shown, in the second embodiment, upper limits are set for the three items of the electric power Wout output from the main battery 41, the electric power Win input to the main battery 41, and the state of the protection switch 106. In addition, in the second embodiment, different criteria are used for determination based on the driving mode and the like for these three items. Regarding the electric power Wout output from the main battery 41, if the driving mode is the automatic driving level 0 to 2, it is set to the second upper limit OL2, and if it is the automatic driving level 3 to 5, it is set to the first upper limit OL1. In addition, regarding the electric power Win input to the main battery 41, if the driving mode is the automatic driving level 0 to 3, it is set to the second upper limit IL2, and if it is the automatic driving level 4 to 5, it is set to the first upper limit IL1. On the other hand, regarding the state of the protection switch 106, when the automatic driving level is 4 or 5 and the protection switch 106 is turned on, the limit OLv based on the vehicle speed and the like is set, and in other cases, the limit OLv based on the vehicle speed and the like is not set.

[0073] exist Figure 8 , the above settings are summarized. As shown in the figure, if the vehicle speed is not limited and the vehicle speed V is below the predetermined value, each upper limit OL1, OL2, IL1, IL2 takes a constant value. At this time, the upper limit OL1 of the electric quantity output from the main battery 41 is the electric quantity Wo1, the upper limit OL2 is the electric quantity Wo2, the upper limit IL1 input to the main battery 41 is the electric quantity Wi1, and the upper limit IL2 is the electric quantity Wi2. The difference from the upper limit on the output side, that is, the electric quantity Wo2, to the electric quantity Wo1 is equivalent to the discharge variation range ΔWo, and the difference from the upper limit on the input side, that is, the electric quantity Wi2, to the electric quantity Wi1 is equivalent to the charge variation range ΔWi. In the second embodiment, the charge variation range ΔWi is set to be smaller than the discharge variation range ΔWo. Therefore, through the electric motor 130 required for braking, regeneration is difficult to be restricted, and the influence on the drivability of the vehicle AM ​​is small. In addition, the charge variation range ΔWi can also be a value of 0. When the charge variation width ΔWi is 0, it is equivalent to keeping the upper limit of the amount of electricity input to the main battery 41 constant regardless of the level of the automatic driving, as in the first embodiment.

[0074] Furthermore, if the protection switch 106 of the indicator 105 is turned on, a limit OLv is imposed on the amount of electricity output from the main battery 41 according to the speed or the like. Therefore, when the driver turns on the protection switch 106 in the case of automatic driving (level 4 or 5), if the vehicle speed V becomes equal to or higher than the threshold value Vth, the amount of electricity output from the main battery 41 is greatly limited, so that the temperature rise of the main battery 41 is suppressed, and the life of the main battery 41 is prolonged. In addition, in the second embodiment, the characteristics that the upper limits OL1, OL2, IL1, and IL2 are gradually reduced when the vehicle speed V becomes higher are the same as in the first embodiment.

[0075] According to the second embodiment described above, in addition to achieving the same effects as the first embodiment, when the driving mode is a mode with little intervention by the driver, the upper limit of the amount of electricity input to the main battery 41 can be reduced to achieve a longer life of the main battery 41. In addition, when the driver turns on the protection switch 106 and intentionally selects the protection mode, a restriction based on the vehicle speed, etc. can be imposed, thereby achieving protection of the main battery 41 and a longer life.

[0076] In the second embodiment, in order to achieve the protection and long life of the battery, the upper limit of the amount of electricity is set according to the degree of intervention of the driver, and the restriction based on the vehicle speed is imposed. However, such restriction can be similarly imposed as long as the use condition is such that the life of the battery may be reduced. As such use conditions, there are parameters indicating the temperature of the battery itself, the temperature or humidity of the use environment, the vibration applied to the battery, the number of charge and discharge cycles when the battery is used, or the cumulative use time of the battery, and the deterioration of the electrolyte inside the battery. The temperature of the battery can be detected by a temperature sensor provided in the battery, and the humidity can be detected by a humidity sensor. Alternatively, the temperature and humidity data of the location of the vehicle AM ​​can be obtained from an external station, such as a weather bureau, a weather news station, etc., via communication. The vibration applied to the battery can be more easily detected by using an acceleration sensor, etc. The number of charge and discharge cycles when the battery is used or the cumulative use time of the battery can be obtained by using a dedicated CPU, etc. provided in the battery pack 40. The detection unit can detect one of them or a combination of them. In addition to this, it is possible to use this together with setting an upper limit on the amount of electricity per unit time input and output from the battery based on differences in the degree of intervention of the driver in vehicle travel.

[0077] Fig. 9 An example of such a process of limiting the amount of power according to the usage conditions is shown. The power limit processing routine shown in the figure is the same as that described in the second embodiment. Figure 6The third embodiment is substantially the same. Instead of S125 to S127 of the second embodiment, S225 to S227 are performed in the third embodiment. Specifically, after the first upper limit or the second upper limit for limiting the amount of electricity input to and output from the main battery 41 is set in S121 or S122, a process is performed to obtain the use conditions that affect the reduction of the life of the battery from the sensor 90. Here, the sensor 90 is the above-mentioned temperature sensor, a detector for detecting the accumulated use time, etc.

[0078] After obtaining the usage conditions, it is determined whether the usage conditions are above a threshold value (S226). For example, it is determined whether the temperature of the main battery 41 is above a predetermined threshold value, or whether the accumulated usage time of the main battery 41 is above a predetermined threshold value. If it is determined to be above the threshold value, that is, the usage condition that may reduce the battery life, the power usage is limited in the same way as the vehicle speed limit in the second embodiment (S227). Regarding this limitation, as in the case of the vehicle speed limit, the higher the battery temperature or the longer the accumulated usage time, the lower the upper limit of the power output from the main battery 41.

[0079] In the above-mentioned embodiments, the vehicle AM ​​is a battery electric vehicle that runs only on the power of a battery, but in addition, any vehicle that uses a battery, such as a fuel cell electric vehicle that runs by combining a fuel cell and a battery, a plug-in hybrid electric vehicle, a hybrid electric vehicle that runs by combining a prime mover and a battery, etc., can be applied.

[0080] The amount of electricity input and output relative to the battery can be either the amount of electricity or the current value. In addition, the amount of electricity input and output for which the upper limit is set can also be either the amount of electricity output from the battery, that is, the discharge side, or the amount of electricity input, that is, the charging side. The charging change amplitude ΔWi and the discharge change amplitude ΔWo can be specified as the absolute value of the charge amount and the discharge amount, or as the rate of change. Regarding the degree of driver intervention in vehicle driving, in the case of automatic driving, as described above, the level 0 to 5 of automatic driving can be used to judge, but it can also be judged by standards other than it. For example, the case where the automatic cruise is turned on can also be determined as the first driving mode, and the case where the automatic cruise is turned off can be determined as the second driving mode. In addition, the case where the following driving mode of following the preceding vehicle is turned on can also be determined as the first driving mode, and the case where the following driving mode of following the preceding vehicle is turned off can also be determined as the second driving mode.

[0081] In each of the above-mentioned embodiments, a part of the structure implemented by hardware can also be replaced by software. At least a part of the structure implemented by software can also be implemented by a discrete circuit structure. In addition, in the case of implementing part or all of the functions of the present disclosure by software, the software (computer program) can be provided in the form of a recording medium that can be read by a computer. "Computer-readable recording medium" is not limited to portable recording media such as floppy disks and CD-ROMs, but also includes various internal storage devices in computers such as RAM, ROM, and external storage devices fixed to computers such as hard disks. That is, "computer-readable recording medium" has a broad meaning including any recording medium that is not temporary but can fix data packets.

[0082] The present disclosure is not limited to the above-mentioned embodiments, and can be implemented in various structures within the scope of the gist thereof. For example, the features of the technology in the embodiments corresponding to the features of the technology in each mode recorded in the content of the invention can be appropriately replaced or combined in order to solve part or all of the above-mentioned problems or to achieve part or all of the above-mentioned effects. In addition, as long as the features of the technology are not described as necessary in this specification, they can be appropriately deleted.

Claims

1. A control device for an electric vehicle, the electric vehicle running on a battery with power input and output, wherein: The electric vehicle control device comprises: a driving mode determination unit for determining whether the driving mode of the vehicle is a first driving mode which is one of two driving modes having different degrees of intervention by the driver in the travel of the vehicle, and a second driving mode in which the degree of intervention by the driver is higher than that of the first driving mode; an upper limit setting unit that sets an upper limit on the amount of electricity per unit time input and output from the battery to a first upper limit amount that is lower than a second upper limit amount that is an upper limit set in the second driving mode, when it is determined that the driving mode is the first driving mode; and The battery control unit controls the amount of electricity input and output to and from the battery in a range not exceeding the first upper limit or the second upper limit according to the driving mode.

2. The electric vehicle control device according to claim 1, wherein: The upper limit setting unit: As the upper limit of the electric quantity, an upper limit of at least one of the charge amount and the discharge amount of the storage battery is set, A charge variation width, which is a variation width from the second upper limit to the first upper limit of the charge amount, is smaller than a discharge variation width, which is a variation width from the second upper limit to the first upper limit of the discharge amount.

3. The electric vehicle control device according to claim 2, wherein: The charging variation amplitude is zero.

4. The electric vehicle control device according to claim 1, wherein: It also includes a detection unit for detecting the usage condition of the battery, The upper limit setting unit further reduces the first upper limit amount when it is determined that the detected usage condition meets a condition predetermined as a usage condition that may reduce the life of the storage battery.

5. The electric vehicle control device according to claim 4, wherein: The usage condition includes at least one of a temperature of the battery and a cumulative usage time. The predetermined condition is that the temperature of the battery is higher than a predetermined temperature and the cumulative usage time of the battery is higher than a predetermined cumulative time.

6. The electric vehicle control device according to claim 1, wherein: The vehicle is a battery-electric vehicle that runs on the power of the battery. By limiting the maximum speed of the vehicle, the discharge amount of the battery is limited.

7. The electric vehicle control device according to claim 6, wherein: further comprising a switch that can be set by an occupant of the vehicle, The battery control unit limits the maximum speed when the driving mode of the vehicle is the first driving mode and the switch is set to on.

8. The electric vehicle control device according to any one of claims 1 to 7, wherein: The first driving mode is an automatic driving mode in which the vehicle is driven without intervention of the driver, and the second driving mode is a manual driving mode in which the vehicle is driven with intervention of the driver.

9. An electric vehicle comprising: Batteries; an electric motor that is driven by the electric power of the battery to output power when the vehicle is running and regenerates electric power when the vehicle is braked; an inverter for exchanging electric power between the battery and the electric motor; a driving control unit that drives the vehicle in a first driving mode that is one of two driving modes in which the degree of intervention of the driver with respect to the vehicle travel is different, or in a second driving mode in which the degree of intervention of the driver is higher than that of the first driving mode; an upper limit setting unit that sets an upper limit on the amount of electricity per unit time input and output from the battery to a first upper limit amount that is lower than a second upper limit amount that is an upper limit set in the second driving mode when the driving mode of the vehicle is the first driving mode; as well as The battery control unit controls the inverter within a range where the amount of electricity input and output to and from the battery does not exceed the first upper limit or the second upper limit set according to a driving mode.

10. The electric vehicle according to claim 9, wherein: The first driving mode is an automatic driving mode in which the vehicle is driven without intervention of the driver, and the second driving mode is a manual driving mode in which the vehicle is driven with intervention of the driver.

11. A control method for an electric vehicle, comprising: When the vehicle is running, the power of the battery is output to the electric motor via the inverter, so that the power for driving the vehicle is output from the electric motor; When the vehicle is braked, at least a portion of the braking force is used to regenerate the electric power generated by the electric motor via the inverter; driving the vehicle in a first driving mode which is one of two driving modes in which the degree of intervention of the driver in the vehicle travel is different, or in a second driving mode in which the degree of intervention of the driver is higher than that of the first driving mode; When the driving mode of the vehicle is the first driving mode, an upper limit of the amount of electricity per unit time input and output from the battery is set to a first upper limit amount that is lower than a second upper limit amount that is an upper limit set in the second driving mode; as well as The inverter is controlled so that the amount of electricity input and output to the battery is lower than the first upper limit or the second upper limit set according to a driving mode.

Images