Method for controlling supply of power to electric vehicle, and system for controlling supply of power to electric vehicle

Abstract

Provided is a power supply control method for an electric vehicle in which: allocated power is set individually for each of a plurality of functional elements that constitute an electric vehicle and that are operated by a driver; a basic priority order for using the functional elements is set for the functional elements; when suppliable power that a battery installed in the electric vehicle can supply simultaneously to the functional elements is lower than the total allocated power, the allocated power for the functional elements is limited in ascending order of basic priority, whereby the total allocated power is limited so as not to exceed the suppliable power; and one of the functional elements is an external power supply system for supplying power to the outside. When information on a requested priority order of the external power supply system is inputted by request of the driver, information on a changed priority sequence including the requested priority order is generated for the functional elements, and the total allocated power is limited so as not to exceed the suppliable power by limiting the allocated power for the functional elements in ascending order of basic priority in the changed priority sequence.

Description

Electric vehicle power supply control method and electric vehicle power supply control system

[0001] The present invention relates to a power supply control method for an electric vehicle and a power supply control system for an electric vehicle.

[0002] JP6164196B discloses a technique for externally supplying power from a battery of an electric vehicle.

[0003] In JP6164196B, when the battery's available power output is limited due to a drop in battery temperature or a drop in the battery's charging rate, the driver's request for external power supply is not reflected, causing the driver to feel uncomfortable.

[0004] Therefore, an object of the present invention is to provide a power supply control method for an electric vehicle and a power supply control system for an electric vehicle that can perform external power supply based on a driver's request even when the output power capacity of a battery mounted on the electric vehicle is reduced.

[0005] According to one aspect of the present invention, there is provided a power supply control method for an electric vehicle, in which an allocated power is individually set for each of multiple functional elements that constitute an electric vehicle and that are subject to operation by a driver, and a basic priority order for using the multiple functional elements is set for the multiple functional elements, and when the available power that a battery mounted on the electric vehicle can simultaneously supply to the multiple functional elements becomes lower than the total of the allocated powers, the allocated power of the functional elements is limited in order of lowest basic priority so as not to exceed the total available power, and one of the multiple functional elements is an external power supply system for supplying power to the outside. In this power supply control method, when information on the requested priority of the external power supply system is input at the driver's request, information on a changed priority order sequence including the requested priorities for the multiple functional elements is generated, and the allocated power of the functional elements is limited in order of lowest priority in the changed priority order so as not to exceed the total available power.

[0006] FIG. 1 is a block diagram of a power supply control system for an electric vehicle according to this embodiment. FIG. 2 is a diagram illustrating an initial state of an operation screen displayed on a touch panel of the power supply control system for an electric vehicle. FIG. 3 is a diagram illustrating a state in which a driver has selected the driver setting mode by tapping the driver setting mode icon in FIG. 2 . FIG. 4 is a diagram illustrating an initial state of the driver setting mode. FIG. 5 is a diagram illustrating a state in which the driver has tapped the selection icons for air conditioning power, driving power, in-vehicle power supply, and external power supply displayed in the driver setting mode in the order of in-vehicle power supply, air conditioning power, and driving power, thereby indicating the priorities. FIG. 6 is a diagram illustrating the relationship between the available output power and the available supply power when the driver setting mode is set as in FIG. 5 , and the sum of the first allocated power allocated as auxiliary power, the fourth allocated power allocated as in-vehicle power supply power, the third allocated power allocated as air conditioning power, and the second allocated power allocated as driving power, when the driver setting mode is set as in FIG. 5 . Fig. 7 is a diagram showing a case where the available output power becomes lower than the sum of the allocated powers from the state shown in Fig. 6 , and the second allocated power is restricted. Fig. 8 is a diagram showing a case where the available output power becomes even lower from the state shown in Fig. 7 , the second allocated power is set to a predetermined first lower limit power, and the third allocated power is restricted. Fig. 9 is a diagram showing a case where the available output power becomes even lower from the state shown in Fig. 8 , and the third allocated power is set to zero. Fig. 10 is a diagram showing a case where the available output power becomes even lower from the state shown in Fig. 9 , and the fourth allocated power is restricted. Fig. 11 is a diagram showing a state where the driver taps on the selection icons for air conditioning power, traction power, in-vehicle power supply, and external power supply displayed in driver setting mode in the order of in-vehicle power supply, external power supply, and air conditioning power, thereby indicating the priorities with numbers. FIG. 12 is a diagram showing the relationship between the sum of the first allocated power allocated as auxiliary power, the fourth allocated power allocated as in-vehicle power supply power, the fifth allocated power allocated as external power supply power, and the third allocated power allocated as air conditioning power, the available output power, and the available supply power when the driver setting mode is set as in FIG. 11 , and a case where the available output power is greater than the sum of the allocated powers.Fig. 13 is a diagram showing a case where the available output power becomes lower than the sum of the allocated powers from the state shown in Fig. 12 , and the third allocated power is limited. Fig. 14 is a diagram showing a case where the available output power becomes even lower from the state shown in Fig. 13 , and the third allocated power is set to zero, and the fifth allocated power is further limited. Fig. 15 is a diagram showing a case where the available output power becomes even lower from the state shown in Fig. 14 , and the power allocable to external power supply becomes lower than the third lower limit power set as the fifth allocated power, and the fifth allocated power is set to zero. Fig. 16 is a diagram showing the priorities of the first allocated power allocated as auxiliary power, the third allocated power allocated as air conditioning power, the fourth allocated power allocated as in-vehicle power supply power, and the second allocated power allocated as drive power when the air-conditioning priority mode is set. Fig. 17 is a diagram showing the priorities of the first allocated power allocated as auxiliary power, the third allocated power allocated as air conditioning power, the fourth allocated power allocated as in-vehicle power supply power, and the second allocated power allocated as drive power when the drive priority mode is set. FIG. 18 is a block diagram illustrating a configuration for supplying power to a second load.

[0007] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0008] <Overall Configuration of Power Supply Control System> Figure 1 is a block diagram of a power supply control system for an electric vehicle according to this embodiment. The power supply control system for a mission vehicle according to this embodiment sets the power allocation for a plurality of power supply systems centered around a battery 31 mounted on the electric vehicle based on the available power output (available power supply) of the battery 31, driver requests, etc.

[0009] The multiple power supply systems centered around the battery 31 include an auxiliary power system (not shown) that supplies power to the electric vehicle's auxiliary devices (a DC / DC converter 7 ( FIG. 18 ) that supplies power to auxiliary devices essential for controlling the electric vehicle, such as a vehicle controller), a drive power system (not shown) that supplies power to the drive motor (an inverter for the drive motor), an air conditioning power system (not shown) that supplies power to the air conditioning system (a compressor that pressurizes and feeds refrigerant for air conditioning), an in-vehicle power feeding system 1 that supplies power mainly to a first load 15 arranged inside the vehicle, an external power feeding system 2 that supplies power mainly to a second load 27 arranged outside the vehicle, and a power supply system 3 that supplies power to the in-vehicle power feeding system 1 and the external power feeding system 2; FIG. 1 only shows the in-vehicle power feeding system 1, the external power feeding system 2, and the power supply system 3.

[0010] The power supply system 3 includes a battery 31, a relay 32 (HV Relay), and a junction box 33 (J / B), which are connected in series in this order. The power supply system 3 (junction box 33) is also connected in parallel to the in-vehicle power supply system 1 and the out-vehicle power supply system 2.

[0011] The battery 31 is configured such that a plurality of battery cells, such as lithium ion batteries (all-solid-state batteries), are stacked and connected in parallel.

[0012] The relay 32 starts or stops the supply of power from the battery 31 to the in-vehicle power feeding system 1 and the out-vehicle power feeding system 2 in response to a command from the controller 5 .

[0013] The junction box 33 normally supplies power from the battery 31 to the in-vehicle power supply system 1 and the external power supply system 2, but if an abnormality such as an overcurrent is detected in the in-vehicle power supply system 1 or the external power supply system 2, the junction box 33 stops supplying power to the in-vehicle power supply system 1 and the external power supply system 2.

[0014] The in-vehicle power supply system 1 includes an inverter 12 (AC / INV) and a first socket 13, which are connected in series in this order. The inverter 12 is connected to a junction box 33. A first plug 14, which is connected to a first load 15, is detachably connected to the first socket 13.

[0015] The first load 15 corresponds to a battery of a high-performance mobile phone (smartphone), a digital camera, or other low-power electronic device.

[0016] The inverter 12 converts the DC voltage of the battery 31 into AC voltage and supplies it to the first socket 13 (first load 15), and the power is controlled by the controller 5, which will be described later.

[0017] The off-vehicle power supply system 2 includes a bidirectional charger 22 (BOBC), an AC socket 23, an external cable 24, and a second socket 25, which are connected in series in this order. The bidirectional charger 22 is connected to a junction box 33. A second plug 26, which is connected to a second load 27, is detachably connected to the second socket 25.

[0018] The second load 27 corresponds to an electrical appliance that consumes relatively high power, such as a cooking appliance, a camping appliance, a gardening appliance, etc. In place of the second load 27, an AC voltage plug (not shown) of a home or a charging station is also connected to the second socket 25.

[0019] The bidirectional charger 22 is a bidirectional on-board charger that converts the DC voltage of the battery 31 into AC voltage and supplies it to the second socket 25 (second load 27) in response to a command from the controller 5. When the AC voltage plug (not shown) is connected, the bidirectional charger 22 converts AC voltage into DC voltage and charges the battery 31. The power used to convert DC voltage to AC voltage and AC voltage to DC voltage are controlled by a command from the controller 5.

[0020] The AC socket 23 connects a circuit inside the electric vehicle (external power supply system 2) to a circuit outside the electric vehicle (external power supply system 2).

[0021] The external cable 24 has one end attached to the second socket 25 and the other end detachably attached to the AC socket 23 .

[0022] The battery 31 is configured such that a plurality of battery cells, such as lithium ion batteries (all-solid-state batteries), are stacked and connected in parallel.

[0023] The battery management unit 4 (BMS: Battery Management System) monitors the state of charge (SOC) and temperature of the battery 31, and calculates the available power that the battery 31 can output based on the state of charge and temperature.

[0024] Here, the available output power is a substantially constant maximum value (rated power) when the current temperature of the battery 31 is between a predetermined lower limit temperature and a predetermined upper limit temperature higher than the lower limit temperature and the charging rate of the battery 31 is equal to or higher than the predetermined lower limit temperature, but when the temperature drops below the lower limit temperature, the internal resistance of the battery 31 increases, causing the power to drop below the substantially constant value, and the power monotonically decreases as the temperature drops below the lower limit temperature. Furthermore, in order to avoid thermal damage to the battery 31 when the temperature of the battery 31 exceeds the upper limit temperature, the available output power must be limited, and the higher the temperature is above the upper limit temperature, the greater the limit must be.

[0025] Therefore, when the current temperature of the battery 31 is lower than the lower limit temperature or higher than the upper limit temperature, the battery management unit 4 estimates the maximum possible output power by referring to a map showing the relationship between the current temperature of the battery 31 and the maximum output power that is not a burden on the battery 31, and outputs information on the estimated maximum possible output power to the controller 5 described below.

[0026] Furthermore, when the charging rate of the battery 31 falls below a predetermined lower limit, the open-circuit voltage decreases, and the available output power decreases, and decreases monotonically as the charging rate falls below the lower limit.

[0027] Therefore, when the charging rate of the battery 31 becomes lower than the lower limit value, the battery management unit 4 estimates the maximum possible output power by referring to a map showing the relationship between the charging rate of the battery 31 and the outputtable power that is the maximum output that does not place a burden on the battery 31, and outputs information on the estimated outputtable power to the controller 5 described below.

[0028] The battery management unit 4 manages the battery cells constituting the battery 31 to prevent overcharging, overdischarging, and home current, and manages the cell voltages of the battery cells to be equalized.

[0029] The controller 5 is configured by one or more computers including, for example, a central processing unit (CPU), a read-only memory (ROM), a random access memory (RAM), an input / output interface (I / O interface), etc. The controller 5 is also programmed to control the auxiliary equipment (DC / DC converter 7 ( FIG. 18 )), the drive motor (drive motor inverter), the air conditioning system (compressor), the in-vehicle power supply system 1 (inverter 12), the off-vehicle power supply system 2 (bidirectional charger 22), etc. at a predetermined control cycle.

[0030] As described above, the controller 5 receives information on the available output power from the battery management unit 4 .

[0031] The first socket 13 is provided with a first detection unit (not shown) that detects the first plug 14 when the first plug 14 is inserted into the first socket 13. Therefore, a first detection signal indicating that the first plug 14 has been detected is input to the controller 5 from the first detection unit (not shown).

[0032] The second socket 25 is provided with a second detection unit (not shown) that detects the second plug 26 when the second plug 26 is inserted into the second socket 25. Therefore, a second detection signal indicating that the second plug 26 has been detected is input to the controller 5 from the second detection unit (not shown).

[0033] The controller 5 sets the allocated power to the auxiliary machinery (first allocated power) (initial value), the allocated power to the drive motor (second allocated power) (initial value), the allocated power to the air conditioning system (third allocated power) (initial value), the allocated power to the in-vehicle power supply system 1 (inverter 12) (fourth allocated power) (initial value), and the allocated power to the off-vehicle power supply system 2 (bidirectional charger 22) (fifth allocated power) (initial value).

[0034] In this case, the controller 5 sets the total allocated power of the first allocated power (initial value) minus the fifth allocated power (initial value) so that it is lower than the available output power (rated power) of the battery 31 .

[0035] In addition, as described below, when the off-vehicle power supply system 2 (off-vehicle power supply) and the driving of the electric vehicle (driving power) are set so that they cannot be selected at the same time, the sum of the first allocated power, the third allocated power, the fourth allocated power, and the fifth allocated power is set to be lower than the rated power, or the sum of the first allocated power, the second allocated power, the third allocated power, and the fourth allocated power is set to be lower than the rated power.

[0036] However, when the available output power output by the battery management unit 4 becomes lower than the total of the allocated powers, it is necessary to limit one of the allocated powers so that the total of the allocated powers does not exceed the available output power.

[0037] However, if the first allocated power of the electric vehicle's accessories (DC / DC converter 7 (FIG. 18)) is limited, the entire electric vehicle will become undriveable and uncontrollable, so the allocated power cannot be limited.

[0038] Therefore, when the electric vehicle is running, the controller 5 controls the total allocated power so that it does not exceed the supplyable power obtained by subtracting the first allocated power from the outputtable power by limiting at least one of the second allocated power to the drive motor, the third allocated power to the air conditioning system, and the fourth allocated power to the in-vehicle power supply system 1.

[0039] Furthermore, when the external power supply system 2 is in use, the controller 5 controls the total allocated power so as not to exceed the supplyable power obtained by subtracting the first allocated power from the outputtable power by limiting at least one of the third allocated power for the air conditioning system, the fourth allocated power for the internal power supply system 1, and the fifth allocated power for the external power supply system 2.

[0040] Mode information is input to the controller 5 via the touch panel 6. The mode information includes information on the priority order (change priority order) for using the drive motor, the air conditioning system, the in-vehicle power supply system 1, and the out-vehicle power supply system 2.

[0041] Therefore, when limiting the second allocated power minus the fifth allocated power, the controller 5 limits the allocated power in ascending order of priority. However, regardless of the magnitude of the available output power, the controller 5 sets the fourth allocated power to zero if the first detection signal is not received, and sets the fifth allocated power to zero if the second detection signal is not received.

[0042] [First Touch Panel Operation] Fig. 2 is a diagram showing an initial state of the operation screen that appears on the touch panel 6 of the power supply control system for an electric vehicle. Fig. 3 is a diagram showing a state in which the driver has selected the driver setting mode by tapping the driver setting mode icon in Fig. 2. Fig. 4 is a diagram showing the initial state of the driver setting mode. Fig. 5 is a diagram showing a state in which the driver has tapped the selection icons for air conditioning power, driving power, in-vehicle power supply, and external power supply that are displayed in the driver setting mode in the order of in-vehicle power supply, air conditioning power, and driving power, thereby indicating the priorities with numbers.

[0043] The touch panel 6 is disposed, for example, on the dashboard inside the vehicle cabin of the electric vehicle, and is used for operations related to the power supply control system of this embodiment and other operations. For example, when the driver performs a tap operation on the touch panel 6 to activate the power supply control system, a mode selection screen appears as shown in FIG.

[0044] The mode selection screen displays a selection icon for "drive priority mode," which prioritizes drive power while driving; a selection icon for "air conditioning priority mode," which prioritizes air conditioning power while driving; a selection icon for "driver setting mode," which allows the driver to arbitrarily set the priorities of air conditioning power, drive power, in-vehicle power supply, and external power supply; and a selection icon for "learning mode," which sets the priorities of air conditioning power, drive power, in-vehicle power supply, and external power supply based on history information (the most frequently selected priority order for each selection icon) of the priorities set in "driver setting mode" (change priority order column).

[0045] As shown in Figure 3, when the driver taps the "Driver Setting Mode" selection icon, the outline of the selection icon and the "Confirm" operation icon at the bottom right of the screen are aligned. When the driver taps the "Confirm" operation icon, the screen switches to a dedicated "Driver Setting Mode" screen as shown in Figure 4.

[0046] As shown in Figure 4, the dedicated screen for the "driver setting mode" displays a selection icon for "air conditioning power," a selection icon for "driving power," a selection icon for "in-vehicle power supply," and a selection icon for "external power supply." It also displays the following warnings: "Tap in the order in which you want to prioritize power use," and "'Driving power' and 'external power supply' cannot be selected at the same time."

[0047] As shown in Figure 5, for example, when the driver taps the "in-vehicle power supply" selection icon, the "air conditioning power" selection icon, and the "driving power" selection icon in that order, the outlines of these selection icons are highlighted, and a "1" is displayed in the upper right corner of the "in-vehicle power supply" selection icon, a "2" is displayed in the upper right corner of the "air conditioning power" selection icon, and a "3" is displayed in the upper right corner of the "driving power" selection icon, allowing the driver to understand the priority. Furthermore, a cross is displayed across the "external power supply" selection icon, visually indicating that "external power supply" is no longer selectable. In addition, since the priority of driving power has been set to third (the lowest), a warning message is displayed stating, "Driving power may be limited."

[0048] Then, when the driver taps the "OK" operation icon at the bottom right, the touch panel 6 outputs mode information related to the "driver setting mode" to the controller 5, which causes the controller 5 to start the first power supply control described below.

[0049] It is also possible to apply a configuration in which the driver can specify only the functional element that he or she wants to give the highest priority to among the four selection icons by tapping one of the selection icons for the four functional elements related to "air conditioning power," "driving power," "in-vehicle power supply," and "external power supply" shown in FIG. 4 and then tapping the "OK" operation icon, and the controller 5 can arbitrarily set the priorities of the remaining functional elements.

[0050] [First power supply control] Figure 6 is a diagram showing the relationship between the sum of the first allocated power allocated as auxiliary power, the fourth allocated power allocated as in-vehicle power supply power, the third allocated power allocated as air conditioning power, and the second allocated power allocated as drive power, the available output power, and the available supply power when the driver setting mode is set as in Figure 5, and when the available output power is greater than the sum of the allocated powers.

[0051] Fig. 7 is a diagram showing a case where the available output power becomes lower than the sum of the allocated powers from the state of Fig. 6, and the second allocated power is restricted. Fig. 8 is a diagram showing a case where the available output power becomes even lower from the state of Fig. 7, the second allocated power is set to a predetermined first lower limit power, and the third allocated power is restricted. Fig. 9 is a diagram showing a case where the available output power becomes even lower from the state of Fig. 8, and the third allocated power is set to zero. Fig. 10 is a diagram showing a case where the available output power becomes even lower from the state of Fig. 9, and the fourth allocated power is restricted.

[0052] The driver has set the priorities (changed priority order) in the order of in-vehicle power supply (fourth allocated power), air conditioning power (third allocated power), and drive power (second allocated power). As a result, as shown in FIG. 6 , the controller 5 sets the priorities in the order of the fourth allocated power (in-vehicle power supply), the third allocated power (air conditioning power), and the second allocated power (drive power), and further sets the first allocated power (auxiliary power) as having a higher priority than the fourth allocated power (in-vehicle power supply).

[0053] As described above, when the outputtable power of battery 31 is the rated power, the sum of the allocated powers of the first allocated power, the fourth allocated power (initial value), the third allocated power (initial value), and the second allocated power (initial value) is lower than the outputtable power (rated power), and the sum of the allocated powers of the fourth allocated power (initial value), the third allocated power (initial value), and the second allocated power (initial value) is lower than the supplyable power.

[0054] As shown in Figure 7, as the output power and supply power decrease, the output power becomes lower than the sum of the allocated power of the first allocated power, the fourth allocated power (initial value), the third allocated power (initial value), and the second allocated power (initial value), and the supply power becomes lower than the sum of the allocated power of the fourth allocated power (initial value), the third allocated power (initial value), and the second allocated power (initial value).

[0055] At this time, the controller 5 controls (limits) the second allocated power (driving power), which has the lowest priority, so that the sum of the allocated powers of the first allocated power, fourth allocated power (initial value), third allocated power (initial value), and second allocated power (subject to limitation) does not exceed the available output power, and so that the sum of the allocated powers of the fourth allocated power (initial value), third allocated power (initial value), and second allocated power (subject to limitation) does not exceed the available supply power.

[0056] As shown in Fig. 8, the available output power and available supply power further decrease from the states shown in Fig. 7, and the controller 5 limits the second allocated power to, for example, a predetermined first lower limit power. When the power that can be allocated as drive power falls below the first lower limit power, the controller 5 keeps the second allocated power (first lower limit power) constant and limits the third allocated power, which has one priority higher than the second allocated power, and limits the third allocated power. This controls (limits) the sum of the first allocated power, fourth allocated power (initial value), third allocated power (limitation target), and second allocated power (first lower limit power) so that it does not exceed the available output power, and so that the sum of the fourth allocated power (initial value), third allocated power (limitation target), and second allocated power (first lower limit power) does not exceed the available supply power.

[0057] In this way, by setting the second allocated power so as not to be lower than the predetermined first lower limit power, the electric vehicle can run with the minimum necessary driving force. Note that the magnitude of the first lower limit power can be set arbitrarily, but it is also possible to set it to zero, thereby making the driving force of the electric vehicle zero, and causing the electric vehicle to coast or stop.

[0058] As shown in Fig. 9, the available output power and available supply power further decrease from the state shown in Fig. 8, and the controller 5 sets the third allocated power to zero. At this time, the controller 5 continues to keep the second allocated power (first lower limit power) constant, and limits the fourth allocated power, which has one priority level higher than the third allocated power. This controls the total allocated power of the first allocated power, the fourth allocated power (limitation target), and the second allocated power (first lower limit power) so that it does not exceed the available output power, and so that the total allocated power of the fourth allocated power (limitation target) and the second allocated power (first lower limit power) does not exceed the available supply power.

[0059] 10, the available output power and available supply power further decrease from the state in Fig. 9, and the controller 5 actually limits the fourth allocated power (subject to limitation) while keeping the second allocated power (first lower limit power) constant. This controls the total allocated power of the first allocated power, the fourth allocated power (subject to limitation), and the second allocated power (first lower limit power) so that it does not exceed the available output power, and so that the total allocated power of the fourth allocated power (subject to limitation) and the second allocated power (first lower limit power) does not exceed the available supply power.

[0060] In addition, when the power that can be allocated as air conditioning power falls below a predetermined second lower limit power due to a decrease in the available output power and available supply power, the third allocated power may be set as the second lower limit power, and the fourth allocated power, which has a higher priority than the third allocated power, may be set as the limit target and the fourth allocated power may be limited. Here, the second lower limit power can be set to any magnitude, as with the first lower limit power. Thus, by setting the second lower limit power to a magnitude other than zero, air conditioning can continue with the minimum necessary power even when the available output power and available supply power decrease, and the air conditioning continuation time can be longer than when the second lower limit power is zero.

[0061] [Second Touch Panel Operation] FIG. 11 is a diagram showing a state in which the driver taps on the icons for air conditioning power, drive power, in-vehicle power supply, and external power supply displayed in the driver setting mode in the order of in-vehicle power supply, external power supply, and air conditioning power, thereby indicating the priority order with numbers.

[0062] As shown in FIG. 11 , for example, the driver taps the "in-vehicle power supply" icon and the "external power supply" icon. At this time, a "1" is displayed in the upper right corner of the "in-vehicle power supply" icon, a "2" is displayed in the upper right corner of the "external power supply" icon, and a cross is placed across the "driving power" icon. If the "air conditioning power" icon is further tapped, a "3" is displayed in the upper right corner of the "air conditioning power" icon, and these numbers allow the driver to understand the priority. Furthermore, since the driving power priority has been set to third (the lowest), a warning message is displayed stating, "Air conditioning power may be limited."

[0063] Then, when the driver taps the "OK" icon at the bottom right, the touch panel 6 outputs mode information related to the "driver setting mode" to the controller 5, which causes the controller 5 to start the second power supply control described below.

[0064] [Second power supply control] Figure 12 is a diagram showing the relationship between the sum of the first allocated power allocated as auxiliary power, the fourth allocated power allocated as in-vehicle power supply power, the fifth allocated power allocated as external power supply power, and the third allocated power allocated as air conditioning power, the available output power, and the available supply power when the driver setting mode is set as in Figure 11, and when the available output power is greater than the sum of the allocated powers.

[0065] Fig. 13 is a diagram showing a case where the available output power becomes lower than the sum of the allocated powers from the state of Fig. 12, and the third allocated power is limited. Fig. 14 is a diagram showing a case where the available output power becomes even lower from the state of Fig. 13, and the third allocated power is set to zero, and the fifth allocated power is further limited. Fig. 15 is a diagram showing a case where the available output power becomes even lower from the state of Fig. 14, and the power that can be allocated to off-vehicle power feeding becomes less than the third lower limit power set as the fifth allocated power, and the fifth allocated power is set to zero.

[0066] The driver has set the priorities (changed priority order) in the order of in-vehicle power supply (fourth allocated power), external power supply (fifth allocated power), and air-conditioning power (third allocated power). As a result, as shown in FIG. 12 , the controller 5 sets the priorities in the order of the fourth allocated power (in-vehicle power supply), the fifth allocated power (external power supply), and the third allocated power (air-conditioning power), and further sets the first allocated power (auxiliary power) as having a higher priority than the fourth allocated power (in-vehicle power supply).

[0067] As described above, when the outputtable power of battery 31 is the rated power, the sum of the allocated powers of the first allocated power, the fourth allocated power (initial value), the fifth allocated power (initial value), and the third allocated power (initial value) is lower than the outputtable power (rated power), and the sum of the allocated powers of the fourth allocated power (initial value), the fifth allocated power (initial value), and the third allocated power (initial value) is lower than the supplyable power.

[0068] As shown in Figure 13, as the output power and supply power decrease, the output power becomes lower than the sum of the allocated power of the first allocated power, the fourth allocated power (initial value), the fifth allocated power (initial value), and the third allocated power (initial value), and the supply power becomes lower than the sum of the allocated power of the fourth allocated power (initial value), the fifth allocated power (initial value), and the third allocated power (initial value).

[0069] At this time, the controller 5 controls the third allocated power (air conditioning power), which has the lowest priority, by limiting (reducing) it so that the sum of the allocated powers of the first allocated power, the fourth allocated power (initial value), the fifth allocated power (initial value), and the third allocated power (subject to limitation) does not exceed the available output power, and so that the sum of the allocated powers of the fourth allocated power (initial value), the fifth allocated power (initial value), and the third allocated power (subject to limitation) does not exceed the available supply power.

[0070] 14, the available output power and available supply power further decrease from the state in Fig. 13, and the controller 5 sets the third allocated power to zero and further limits the fifth allocated power. As a result, control is performed so that the sum of the allocated powers of the first allocated power, the fourth allocated power (initial value), and the fifth allocated power (subject to limitation) becomes lower than the available output power, and the sum of the allocated powers of the fourth allocated power (initial value) and the fifth allocated power (subject to limitation) becomes lower than the available supply power.

[0071] As shown in FIG. 15 , when the available output power and available supply power further decrease from the state shown in FIG. 14 , the controller 5 calculates the fifth allocated power as a value that is equal to or greater than zero but lower than a preset third lower limit power (predetermined power). At this time, if the power that can be allocated as the fifth allocated power is equal to or greater than zero but lower than the third lower limit power, the controller 5 sets the fifth allocated power to zero. As a result, when the power that can be supplied to the “external power feeding” (fifth allocated power) falls below the third lower limit power and the “external power feeding” cannot be effectively performed, the “external power feeding” is terminated, thereby increasing the amount of power supplied to the “in-vehicle power feeding” (fourth allocated power), which has a higher priority than the “external power feeding” (fifth allocated power). If the available output power and available supply power subsequently decrease further, the fourth allocated power is limited (see FIG. 10 ). It is also possible to set the fourth allocated power to zero to terminate the “in-vehicle power feeding” when the power that can be supplied to the “in-vehicle power feeding” falls below the predetermined third lower limit power and the “in-vehicle power feeding” cannot be effectively performed.

[0072] [Air Conditioning Priority Mode] FIG. 16 is a diagram showing the priorities of the first allocated power allocated as auxiliary power, the third allocated power allocated as air conditioning power, the fourth allocated power allocated as in-vehicle power supply power, and the second allocated power allocated as drive power when the air conditioning priority mode is set.

[0073] When the driver selects the "air conditioning priority mode" in the mode selection shown in FIG. 2, the controller 5 sets the priority in the following order when the outside air temperature or the temperature inside the vehicle cabin is higher or lower than an optimum temperature range (for example, 18°C-22°C) and is outside the optimum temperature range: first allocated power (auxiliary power), third allocated power (air conditioning system), fourth allocated power (in-vehicle power supply), second allocated power (driving power) (or fifth allocated power); and when the outside air temperature or the temperature inside the vehicle cabin is within the optimum temperature range, the controller 5 sets the priority in the following order: first allocated power (auxiliary power), fourth allocated power (in-vehicle power supply), third allocated power (air conditioning system), second allocated power (driving power) (or fifth allocated power).

[0074] In this way, when there is a possibility that the driver will use the air conditioning system at a high output, the priority of the third allocated power is increased, allowing the driver to use the air conditioning system without complaint, and when there is a low possibility that this will occur, the priority of the third allocated power is decreased and instead, for example, the fourth allocated power (in-vehicle power supply) is increased, allowing the driver to use the in-vehicle power supply without complaint.

[0075] Even when the driver selects the air conditioning priority mode, the driver can arbitrarily set the priority of the fourth allocated power through the touch panel 6 (FIGS. 1 and 2), and the third allocated power and the second allocated power are set to a priority different from that of the fourth allocated power. Also, the driver can set the priority of the fifth allocated power through the touch panel 6 (FIGS. 1 and 2), and the third allocated power and the fourth allocated power are set to a priority different from that of the fifth allocated power.

[0076] [Drive Priority Mode] FIG. 17 is a diagram showing the priorities of the first allocated power allocated as auxiliary power, the third allocated power allocated as air conditioning power, the fourth allocated power allocated as in-vehicle power supply power, and the second allocated power allocated as drive power when the drive priority mode is set.

[0077] The controller 5 (FIG. 1) can acquire the position of the vehicle (electric vehicle) and traffic information (such as the locations of charging spots) on the roads the vehicle is traveling on via the Internet, etc. The battery management unit 4 (FIG. 1) also outputs information on the charging rate of the battery 31 to the controller 5.

[0078] When the driver selects the "drive priority mode" in the mode selection shown in Fig. 2, the controller 5 normally sets the priority in the following order: first allocated power (auxiliary power), third allocated power (air conditioning system), fourth allocated power (in-vehicle power supply), and second allocated power (drive power). Note that even when the driver does not execute the mode selection shown in Fig. 2, these priorities (basic priority) are set, with "air conditioning power" being set to the highest priority, excluding auxiliary power.

[0079] When the charge rate of the battery 31 falls below a predetermined charge rate and the controller 5 determines that a charging spot is located at the vehicle's destination and within a predetermined distance, the controller 5 sets priorities in the following order: first allocated power (auxiliary power), second allocated power (driving power), third allocated power (air conditioning system), and fourth allocated power (in-vehicle power supply), and displays, for example, a message on the touch panel 6 ( FIG. 2 ) saying "Please charge at the next charging spot" to prompt the driver to charge the battery 31. Furthermore, regardless of the charge rate of the battery 31, the controller 5 may switch the priority order as described above and similarly prompt the driver to charge the battery when it determines that a charging spot is located at the vehicle's destination and within a predetermined distance.

[0080] Even when the driver selects the drive priority mode, the driver can arbitrarily set the priority of the fourth allocated power (change priority sequence) through the touch panel 6 (Figures 1 and 2), and the third allocated power and the second allocated power are set to a priority different from the priority of the fourth allocated power (change priority sequence).

[0081] [Power Supply to Second Load 27] Fig. 18 is a block diagram illustrating a configuration for supplying power to the second load 27. The controller 5 includes, for example, a first controller 51 that controls the bidirectional charger 22 and a second controller 52 that controls the relay 32. In Fig. 18, the in-vehicle power feeding system 1 (first load 15) and the junction box 33 shown in Fig. 1 are omitted.

[0082] Here, the description will be given assuming that the first load 15 (first plug 14) is not connected to the in-vehicle power feeding system 1 (first socket 13) and the second load 27 is connected to the external power feeding system 2 (second socket 25) (see FIG. 1 ). However, the system functions similarly in a state in which the first load 15 is connected to the in-vehicle power feeding system 1 and the second load 27 is connected to the external power feeding system 2 (see FIG. 1 ), or in a state in which the first load 15 is connected to the in-vehicle power feeding system 1 and the second load 27 is not connected to the external power feeding system 2 (see FIG. 1 ). When the available output power and the available supply power decrease, causing the power that can be supplied to the in-vehicle power feeding system 1 (first load 15) to be lower than a predetermined power (fourth lower limit power (the magnitude of which can be set arbitrarily)), the fourth allocated power may be set to zero, and the allocated power of the power of functional elements having a higher priority than the in-vehicle power feeding may be limited, and the allocated power may be limited.

[0083] The first controller 51 receives a second detection signal from a second detection unit (not shown) arranged in the second socket 25, thereby detecting that a second load 27 has been connected to the second socket 25.

[0084] Mode information is input to the first controller 51 from the touch panel 6, and information on the priority order (changed priority order sequence) of the second allocated power (driving power), the third allocated power (air conditioning power), and the fifth allocated power (external power supply) set by the driver (here, the fourth allocated power (in-vehicle power supply) is not incorporated into the priority order, or even if it is incorporated into the priority order, its value is set to zero), or information on the priority mode is input.

[0085] The second controller 52 receives information on the available output power from the battery management unit 4 and information on the required power from the DC / DC converter 7 that drives the auxiliary equipment. Note that the required power from the DC / DC converter 7 can be considered to be constant (first allocated power), and input of the required power information can be omitted.

[0086] The second controller 52 calculates the available power supply by subtracting the required power (first allocated power) from the available output power, and outputs information about the available power supply to the first controller 51 .

[0087] The first controller 51 has information on the second allocated power (initial value), the third allocated power (initial value), and the fifth allocated power (initial value).

[0088] If the available power supply is higher than the sum of the fifth allocated power (initial value) and the third allocated power (initial value) or lower than this sum and the fifth percentage power is not subject to limitation, the first controller 51 sends an open signal to the second controller 52, which causes the second controller 52 to set the relay 32 to the on state. The first controller 51 also sets the output of the bidirectional charger 22 to the fifth allocated power (initial value). As a result, the second load 27 is charged with the fifth allocated power (initial value).

[0089] If the available power supply is lower than the sum of the fifth allocated power (initial value) and the third allocated power (initial value), the fifth percentage power is subject to limitation, and its magnitude is equal to or greater than a predetermined third lower limit power, the first controller 51 sends an open signal to the second controller 52, causing the second controller 52 to set the relay 32 to the on state. The first controller 51 also sets the output of the bidirectional charger 22 to the fifth allocated power (power after limitation). As a result, the second load 27 is charged with the fifth allocated power (power after limitation that is equal to or greater than the third lower limit power).

[0090] If the fifth percentage power is lower than the total allocated power, and the fifth percentage power is subject to limitation and its magnitude is less than the predetermined third lower limit power, the first controller 51 sends a close signal to the second controller 52, causing the second controller 52 to turn off the relay 32. The first controller 51 also sets the output of the bidirectional charger 22 to zero, thereby stopping charging of the second load 27.

[0091] [Effects of this embodiment] In the power supply control method for an electric vehicle according to this embodiment, allocated power is individually set for a plurality of functional elements (auxiliary equipment, drive motor, air conditioning system, on-board power supply system 1, off-board power supply system 2) that constitute an electric vehicle and are to be operated by a driver (drive motor, air conditioning system, on-board power supply system 1, off-board power supply system 2), and a basic priority order for using the plurality of functional elements (priority order set in the order of third allocated power, fourth allocated power, second allocated power (left side of FIG. 17 )) is set, and when the available power that can be simultaneously supplied from battery 31 mounted on the electric vehicle to the plurality of functional elements becomes lower than the sum of the allocated powers, the basic priority order is set. This power supply control method for an electric vehicle limits the allocated power of functional elements in ascending order of priority so that the total allocated power does not exceed the available power supply, and in which one of a plurality of functional elements is an external power supply system (in-vehicle power supply system 1 and / or external power supply system 2) for supplying power to the outside, generates information on a changed priority sequence (FIGS. 6 and 12) including the requested priorities for the plurality of functional elements when information on the requested priority of the external power supply system (FIG. 5) is input by a driver's request (operation of a touch panel 6), and limits the allocated power of functional elements in descending order of priority in the changed priority sequence so that the total allocated power does not exceed the available power supply.

[0092] The above method allows the driver to arbitrarily set the priority order for using the external power supply systems (in-vehicle power supply system 1, external power supply system 2), so that even in a situation where the available power supply of battery 31 is reduced, external power supply can be performed in accordance with the driver's request without causing any discomfort to the driver.

[0093] In this embodiment, when the allocated power of multiple functional elements is limited due to a decrease in the available power supply, the allocated power of the functional element that is the target of the limit is limited while maintaining the allocated power of all functional elements that have a higher priority in the changed priority sequence than the functional element whose allocated power is to be limited, and then, after the available power supply decreases further and the allocated power becomes zero, the allocated power of the functional element that is one priority higher in the changed priority sequence than the functional element whose allocated power has been set to zero is set as the next target of limitation.

[0094] With the above method, even if the available power supply of the battery 31 decreases, the allocated power of functional elements with high priority rankings is not immediately restricted, so that the power supply intended by the driver can be provided to each functional element.

[0095] In this embodiment, multiple priority modes are set in the change priority sequence in which the priorities of at least some of the multiple functional elements other than the external power supply system (in-vehicle power supply system 1, external power supply system 2) differ from each other, and the priority modes are set so that the driver can select them.

[0096] The above method allows multiple priority modes to be set according to the driver's usage scenario, and the driver can select a specific priority mode after understanding the usage scenario, so the driver can easily set the power supply priority as intended.

[0097] In this embodiment, when the allocated power of the external power feeding systems (in-vehicle power feeding system 1, external power feeding system 2) is limited and the allocated power is limited to less than predetermined power (fourth lower limit power, third lower limit power) that is lower than the initial value of the allocated power of the external power feeding systems, the allocated power (fourth allocated power, fifth allocated power) of the external power feeding systems is set to zero.

[0098] With the above method, when the power that can be supplied to the external power supply system falls below predetermined power levels (fourth lower limit power, third lower limit power) and effective power supply to the power supply target connected to the external power supply system cannot be performed, the power supply to the external power supply system is terminated, thereby making it possible to increase the amount of power supplied to functional elements that have a higher priority than the external power supply system.

[0099] In this embodiment, when an allocated power (first allocated power) and a basic priority (e.g., 1st) are set for a specific functional element (auxiliary equipment) that is one of multiple functional elements and is not subject to driver control, the output power that the battery 31 can output is calculated based on the state of the battery 31, the supplyable power is set as the difference obtained by subtracting the allocated power (first allocated power) of the specific functional element (auxiliary equipment) from the output power, and the priority of the specific functional element (auxiliary equipment) in the changed priority order is set to the basic priority order (e.g., 1st) of the specific functional element (auxiliary equipment).

[0100] By using the above method, the priority (for example, number 1) of the allocated power of the auxiliary equipment that is essential for controlling the electric vehicle can be ensured, so that the electric vehicle can be stably controlled even if the output power and supply power of the battery 31 decrease.

[0101] In this embodiment, the multiple functional elements that are operated by the driver include a drive motor that drives the electric vehicle and an air conditioning system that conditions the interior of the electric vehicle, and the priority modes include a drive priority mode that sets the priority of the drive motor in the change priority sequence based on traffic information (information about the position of the host vehicle (electric vehicle) and information about the positions of charging spots), and an air conditioning priority mode that sets the priority of the air conditioning system in the change priority sequence based on the ambient temperature of the electric vehicle.

[0102] With the above configuration, it is possible to select between a drive priority mode, which changes the priority of the drive motor based on traffic information, and an air conditioning priority mode, which changes the priority of the air conditioning system based on the ambient temperature of the electric vehicle.This allows the priority of functional elements set by the driver to be changed in response to changes in the ambient environment of the electric vehicle, thereby increasing convenience for the driver.

[0103] In this embodiment, the priority modes include a setting priority mode in which the driver can further set the change priority sequence of multiple functional elements other than the external power supply system among the multiple functional elements, and a learning mode in which the change priority sequence is set upon request based on history information of the change priority sequence.

[0104] The above method allows the driver to select the setting priority mode, thereby increasing the freedom in selecting the priority of the allocated power, and also allows the driver to easily set the priority of the allocated power as intended by the driver, by selecting the learning mode.

[0105] The power supply control system for an electric vehicle of this embodiment includes a battery 31 mounted on the electric vehicle, an allocated power setting unit (controller 5) that sets allocated power individually to a plurality of functional elements (auxiliary equipment, drive motor, air conditioning system, in-vehicle power supply system 1, external power supply system 2) that constitute the electric vehicle and are to be operated by a driver (auxiliary equipment, drive motor, air conditioning system, in-vehicle power supply system 1, external power supply system 2), a priority setting unit (controller 5) that sets basic priorities for using the plurality of functional elements (priorities set in this order of third allocated power, fourth allocated power, second allocated power (left side of Figure 17)), and a limiting unit that limits the allocated power of functional elements in order of lowest basic priority when the available power that can be simultaneously supplied by the battery 31 to the plurality of functional elements becomes lower than the total allocated power. and a power control unit (controller 5) that limits the total allocated power so as not to exceed the available power supply, and one of the plurality of functional elements is an external power supply system (in-vehicle power supply system 1 and / or off-vehicle power supply system 2) for supplying power to the outside, and further includes an input unit (touch panel 6) that generates information on requested priorities of the external power supply systems (in-vehicle power supply system 1 and / or off-vehicle power supply system 2) and outputs the information to the power control unit (controller 5), and when the requested priority information is input, the power control unit (controller 5) generates information on a changed priority sequence ( FIGS. 6 and 12 ) that includes requested priorities ( FIG. 5 ) for the plurality of functional elements, and limits the allocated power of the functional elements in ascending order of priority in the changed priority sequence, thereby limiting the total allocated power so as not to exceed the available power supply.

[0106] With the above configuration, the driver can arbitrarily set the priority order for using the external power supply systems (in-vehicle power supply system 1, external power supply system 2), so that external power supply can be performed in accordance with the driver's request even when the available power supply of battery 31 is reduced.

[0107] Although the embodiments of the present invention have been described above, the above embodiments merely illustrate some of the application examples of the present invention, and it is not intended that the technical scope of the present invention be limited to the specific configurations of the above embodiments.

Claims

1. A power supply control method for an electric vehicle, in which allocated power is set individually for a plurality of functional elements that constitute an electric vehicle and are subject to operation by a driver, and a basic priority order for using the functional elements is set for the plurality of functional elements, and when the available power that a battery mounted on the electric vehicle can simultaneously supply to a plurality of functional elements becomes lower than the sum of the allocated powers, the allocated power of the functional elements is limited in order of lowest basic priority so as not to cause the sum of the allocated powers to exceed the available power supply, and one of the plurality of functional elements is an external power supply system for supplying power to the outside, wherein, when information on the requested priority of the external power supply system is input at the request of the driver, information on a changed priority order sequence including the requested priority for the plurality of functional elements is generated, and the allocated power of the functional elements is limited in order of lowest priority in the changed priority order so as not to cause the sum of the allocated powers to exceed the available power supply.

2. A power supply control method for an electric vehicle as set forth in claim 1, wherein, in a case where the allocated power of a plurality of functional elements is limited due to a decrease in the available power supply, the allocated power of the functional element that is the target of the limit is limited while maintaining the allocated power of all functional elements that have a higher priority in the changed priority sequence than the functional element that is the target of the limit's allocated power, and then, after the available power supply further decreases and the allocated power becomes zero, the allocated power of the functional element that is one priority higher in the changed priority sequence than the functional element whose allocated power has been set to zero is set as the next target of the limit.

3. A power supply control method for an electric vehicle according to claim 1, wherein a plurality of priority modes are set in which the priorities of at least some of the plurality of functional elements other than the external power supply system among the plurality of functional elements in the changed priority order are different from each other, and the priority modes are set so that the driver can select one of them.

4. The power supply control method for an electric vehicle according to claim 1, wherein the allocated power of the external power supply system is set to zero when the allocated power of the external power supply system is limited to less than a predetermined power that is lower than an initial value of the allocated power of the external power supply system.

5. A power supply control method for an electric vehicle as described in claim 1, wherein, when the allocated power and the basic priority are set for a specific functional element that is not under the control of the driver among multiple functional elements, the method calculates the output power that the battery can output based on the state of the battery, sets the supplyable power by the difference obtained by subtracting the allocated power of the specific functional element from the output power, and sets the priority of the specific functional element in the changed priority sequence to the basic priority of the specific functional element.

6. A power supply control method for an electric vehicle as described in claim 3, wherein the multiple functional elements that are operated by the driver include a drive motor that drives the electric vehicle and an air conditioning system that conditions the interior of the electric vehicle, and the priority modes include a drive priority mode that sets the priority of the drive motor in the change priority sequence based on traffic information, and an air conditioning priority mode that sets the priority of the air conditioning system in the change priority sequence based on the ambient temperature of the electric vehicle.

7. The power supply control method for an electric vehicle according to claim 3, wherein the priority modes include: a setting priority mode in which the driver can further set the change priority sequence for multiple functional elements other than the external power supply system among the multiple functional elements; and a learning mode in which the change priority sequence is set at the time of the request based on history information of the change priority sequence.

8. A power supply control system for an electric vehicle comprising: a battery mounted on an electric vehicle; an allocated power setting unit that sets an allocated power individually to a plurality of functional elements that constitute the electric vehicle and are operable by a driver; a priority setting unit that sets, for the plurality of functional elements, a basic priority order for using the functional elements; and a power control unit that, when the available power that the battery can simultaneously supply to the plurality of functional elements becomes lower than the sum of the allocated powers, limits the allocated power of the functional elements in order of lowest basic priority so as not to cause the sum of the allocated powers to exceed the available power supply, wherein one of the plurality of functional elements is an external power supply system for supplying power to the outside, and further comprises an input unit that generates information of a requested priority order of the external power supply system and outputs it to the power control unit, wherein the power control unit, when the requested priority information is input, generates information of a changed priority order sequence including the requested priority order for the plurality of functional elements, and limits the allocated power of the functional elements in order of lowest priority in the changed priority order so as not to cause the sum of the allocated powers to exceed the available power supply.

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