vehicle

Abstract

The present invention provides a vehicle that can protect components energized by a power storage device while increasing the vehicle's driving force provided by the power storage device as needed. [Solution] The vehicle comprises a power storage device, a motor generator, components energized by the power storage device, and a control device. The motor generator is configured to drive the vehicle with power output from the power storage device in the powered state, and to charge the power storage device with the regenerated power generated in the regenerative state. The control device is configured to perform input and output limits on the power storage device in each of the first and second driving modes to suppress heat generation of the components. The control device is configured to perform stricter input limits on the power storage device in the second driving mode than in the first driving mode.

Description

Technical Field

[0001] The present disclosure relates to a vehicle that can be driven by electric power output from a power storage device.

Background Art

[0002] Japanese Unexamined Patent Application Publication No. 2017-071299 (Patent Document 1) discloses a technique for calculating an evaluation value related to the temperature level of a component energized by a power storage device and restricting the charge / discharge power of the power storage device when the calculated evaluation value exceeds a threshold value.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above technique, excessive temperature rise of components is suppressed by restricting the charge / discharge power of the power storage device. However, in a vehicle driven by electric power output from a power storage device, restricting the charge / discharge power of the power storage device may result in insufficient driving force (vehicle acceleration performance).

[0005] The present disclosure has been made to solve the above problems, and an object thereof is to provide a vehicle that can protect components energized by a power storage device and increase the driving force of the vehicle by the power storage device as needed.

Means for Solving the Problems

[0006] According to one embodiment of the present disclosure, the following vehicle is provided: The vehicle comprises a power storage device, a motor generator, components energized by the power storage device, and a control device. The motor generator is configured to drive the vehicle with power output from the power storage device in the powered state, and to charge the power storage device with regenerated power in the regenerative state. The control device is configured to perform input and output limits on the power storage device in a first driving mode and a second driving mode, respectively, to suppress heat generation of the components. The control device is configured to perform a stricter input limit on the power storage device in the second driving mode than in the first driving mode. [Effects of the Invention]

[0007] According to this disclosure, it becomes possible to provide a vehicle that can protect components energized by the energy storage device while increasing the vehicle's driving force by the energy storage device as needed. [Brief explanation of the drawing]

[0008] [Figure 1] This figure shows the schematic configuration of a vehicle according to an embodiment of the present disclosure. [Figure 2] This flowchart shows the driving mode setting control according to this embodiment. [Figure 3] This is a flowchart showing the control of the first driving mode according to this embodiment. [Figure 4] This is a flowchart showing the control of the second driving mode according to this embodiment. [Figure 5] Figure 4 shows a flowchart illustrating a modified version of the process shown in Figure 4. [Modes for carrying out the invention]

[0009] Embodiments of this disclosure will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and their descriptions will not be repeated.

[0010] Figure 1 shows the configuration of a vehicle according to this embodiment. In Figure 1, the vertical and longitudinal directions are shown as being perpendicular to each other. "Forward" corresponds to the direction of travel of the vehicle, and "rearward" is the opposite direction. "Down" corresponds to the vertical direction (direction of gravity), and "up" is the opposite direction.

[0011] Referring to Figure 1, the vehicle 1000 includes a battery pack 100. The battery pack 100 is fixed, for example, under the floor of the vehicle 1000. However, the mounting configuration of the battery pack 100 is arbitrary. For example, the battery pack 100 may be placed on the floor of the vehicle 1000. The battery pack 100 corresponds to an example of the "energy storage device" according to this disclosure.

[0012] Vehicle 1000 is further equipped with an ECU (Electronic Control Unit) 500 that performs charge and discharge control of the battery pack 100, and various sensors (position sensor, outside temperature sensor, vehicle speed sensor, odometer, etc., not shown) that detect the status of vehicle 1000 in real time. The detection results of the various sensors are output to the ECU 500.

[0013] The ECU 500 includes a processor 510 and a storage device 520. The storage device 520 is configured to store stored information. In the ECU 500, various controls are performed by the processor 510 executing a program stored in the storage device 520. In addition to the program, the storage device 520 also stores various information used by the program. The ECU 500 is an example of a "control device" according to this disclosure.

[0014] The vehicle 1000 further comprises a drive unit 20 for driving the vehicle 1000, a braking unit 30 (brake system) for applying braking force to the vehicle 1000, an inlet 410, a charger 420 (onboard charger), and an HMI (Human Machine Interface) 600.

[0015] The HMI600 includes an input device and a display device. The HMI600 may also include a touch panel display. The input device outputs signals to the ECU500 in response to user input. The input device of the HMI600 includes a driving control unit (e.g., accelerator pedal, brake pedal, and steering wheel) for the user to request acceleration, deceleration, and steering from the vehicle 1000 (ECU500). The HMI600 further includes a navigation system. The navigation system comprises a storage device for storing map information and a control device for displaying the map on a display device. The map information includes location information of the racetrack. The navigation system is configured to display the location of the vehicle 1000 on the map in real time using a positioning system such as GPS (Global Positioning System). The navigation system refers to the map information to determine the location of the vehicle 1000 and performs route searching to find the optimal route from the vehicle 1000's current location to the destination.

[0016] The drive unit 20 includes a PCU (Power Control Unit) 21, an MG (Motor Generator) 22, and an engine 23. The vehicle 1000 is configured to run using the power output from the battery pack 100. The user can manually drive the vehicle 1000 through the driving control unit. The vehicle 1000 is, for example, a PHEV (Plug-in Hybrid Electric Vehicle). However, the vehicle 1000 may be another electric vehicle (xEV), such as a BEV (Battery Electric Vehicle) or an HEV (Hybrid Electric Vehicle).

[0017] The battery pack 100 includes a plurality of cells 10 (power storage cells) each functioning as a secondary battery. The plurality of cells 10 are stacked and constrained in a predetermined direction to form a battery stack. The battery stack is a power storage module in which a plurality of electrically connected cells 10 are modularized. Examples of the cell 10 include secondary batteries such as lithium-ion batteries, nickel-metal hydride batteries, or sodium-ion batteries. The type of the secondary battery may be a liquid secondary battery or an all-solid-state secondary battery. The exterior of the cell 10 may be a laminate exterior or a metal rectangular case. Each battery stack may include only the same type of cells or different types of cells.

[0018] The battery pack 100 further includes a monitoring unit 100a for monitoring the state of the battery stack. The monitoring unit 100a includes various sensors for detecting the state (for example, current, voltage, and temperature) of each cell 10 included in the battery stack. The detection results of each sensor included in the monitoring unit 100a are output to the ECU 500. The monitoring unit 100a and the ECU 500 may function as a BMS (Battery Management System).

[0019] <e000089>The ECU 500 is configured to variably set a first guard value (hereinafter referred to as "Win") indicating the upper limit value of the input power of the battery pack 100 and a second guard value (hereinafter referred to as "Wout") indicating the upper limit value of the output power of the battery pack 100. Specifically, the ECU 500 may variably set Wout and Win based on the heat generation state of a component E (for example, a junction box) through which current flows as the battery stack discharges or charges. Details of the setting method of Wout and Win will be described later (see FIGS. 3 and 4).

[0020] Vehicle 1000 is configured to perform external charging of the battery pack 100 (charging by power supplied from outside the vehicle) while parked. The inlet 410 is configured to be connectable to a charging cable of a power supply facility (not shown) provided outside the vehicle. The charger 420 performs AC / DC conversion. During external charging, the ECU 500 controls the charger 420 while AC power is input from outside the vehicle to the charger 420 via the inlet 410. The charger 420 converts the AC power into DC power according to a control command from the ECU 500 and outputs the DC power to the battery pack 100. Thereby, each battery included in the battery pack 100 is charged.

[0021] The PCU 21 includes, for example, an inverter. The MG 22 functions as a driving motor and rotates the drive wheels 24 of the vehicle 1000. The MG 22 drives the vehicle 1000 using the power output from the batteries in the battery pack 100. Specifically, the PCU 21 drives the MG 22 using the power supplied from the battery pack 100. Thereby, the MG 22 enters a power running state. The MG 22 in the power running state converts power into torque. The torque is transmitted to the drive wheels 24. The MG 22 enters a power running state, for example, in response to an accelerator operation on the operation unit. Also, the MG 22 enters a regeneration state, for example, based on the release of the accelerator operation on the operation unit, and generates regenerative power with the regenerative brake. Also, a braking force is applied to the vehicle 1000 by the regenerative brake. Then, the MG 22 charges each battery included in the battery pack 100 with the generated regenerative power.

[0022] The engine 23 functions as an internal combustion engine and drives the vehicle 1000 using the combustion energy of fuel. Specifically, the engine 23 generates power by the combustion energy of fuel supplied from a fuel tank (not shown). The generated power is transmitted to the drive wheels 24. The exhaust pipe 23a is connected to the engine 23 and discharges the exhaust of the engine 23 to the outside of the vehicle.

[0023] The braking device 30 is configured to decelerate the vehicle 1000. The braking device 30 functions as a service brake. The braking device 30 includes, for example, a braking member that applies braking force to each wheel of the vehicle 1000 and an actuator that drives the braking member. The braking device 30 may be a hydraulic disc brake system. The braking device 30 may apply braking force to each wheel of the vehicle 1000 in response to a brake operation on the driving control unit. For example, the user can bring the vehicle 1000 to a stop by decelerating the moving vehicle 1000 by pressing the brake pedal.

[0024] Vehicle 1000 further includes an SMR (System Main Relay) 100b. The input device of HMI 600 further includes a start switch for vehicle 1000. SMR 100b is, for example, an electromagnetic mechanical relay. SMR 100b is located between the battery pack 100 and the drive unit 20 and charger 420, respectively. Generally, the start switch is called a "power switch" or "ignition switch". By operating the start switch, the user can put vehicle 1000 into a Ready-ON state or a Ready-OFF state. In the Ready-ON state, the control system of vehicle 1000 (including ECU 500) is operational and SMR 100b is connected. The activated ECU 500 connects SMR 100b. In the Ready-OFF state, the control system of vehicle 1000 is stopped (including sleep state) and SMR 100b is disconnected.

[0025] The HMI600 input device further includes a mode selection switch that selects the driving mode of the vehicle 1000 in response to user input. The vehicle 1000 is configured to drive in one driving mode selected from several driving modes when in the Ready-ON state. In this embodiment, the vehicle 1000 is configured to be able to drive in normal mode (first driving mode) and circuit mode (second driving mode). Normal mode is a driving mode suitable for normal driving (e.g., driving on public roads and highways). Circuit mode is a driving mode more suitable for circuit driving (e.g., driving on a race track) than normal mode. In circuit mode, the torque fluctuation in response to accelerator operation (e.g., the amount the accelerator pedal is pressed) may be set more sensitively than in normal mode. Also, in circuit mode, the control of the MG22 and engine 23 may be set to prioritize power. In normal mode, the MG22 and engine 23 may be controlled to achieve a balance between power and energy efficiency (fuel consumption and electric efficiency).

[0026] Figure 2 is a flowchart showing the driving mode setting control by the ECU 500. The processing flow F1 shown in Figure 2 is repeatedly executed by the ECU 500 when the vehicle 1000 is in the Ready-ON state. "S" in the flowchart represents a step.

[0027] In processing flow F1, ECU500 determines whether circuit mode was selected by the user in S11. The user selecting circuit mode means the user requests circuit mode from ECU500.

[0028] In this embodiment, the touch panel display functions as the mode selection switch described above. In the Ready-ON state, the touch panel display of the HMI600 displays, for example, image Sc1 shown in Figure 2. Image Sc1 includes a mode selection switch M (for example, a toggle switch). The user can select either normal mode or circuit mode by operating the mode selection switch M. If the user selects circuit mode, it is determined to be YES in S11 and the process proceeds to S14. If the user selects normal mode, it is determined to be NO in S11 and the process proceeds to S12.

[0029] In S12, ECU500 works with, for example, the navigation system to determine whether vehicle 1000 is located within the circuit. If it is determined that vehicle 1000 is located within the circuit (YES in S12), the process proceeds to S14. If it is determined that vehicle 1000 is not located within the circuit (NO in S12), the process proceeds to S13.

[0030] In S13, ECU500 sets the driving mode of vehicle 1000 to normal mode. In S14, ECU500 sets the driving mode of vehicle 1000 to circuit mode. Once the driving mode is set by either S13 or S14, the process returns to the first step (S11). In this way, whether the user selects circuit mode or vehicle 1000 is located on a circuit, ECU500 sets the driving mode of vehicle 1000 to circuit mode.

[0031] When the normal mode is set by the process in S13, the processing flow F2 shown in Figure 3, which is described below, is started. Also, during the period when the vehicle 1000 is in the normal mode, the ECU 500 performs driving control of the vehicle 1000 corresponding to the normal mode in response to manual driving by the user. Processing flow F2 is executed in parallel with the aforementioned processing flow F1 (Figure 2) and the driving control for the normal mode (not shown).

[0032] Figure 3 is a flowchart showing the charge and discharge control of the battery pack 100 in normal mode. In processing flow F2, the ECU 500 obtains an evaluation value F of component E powered by the battery pack 100 in S21. In this embodiment, component E is located inside the battery pack 100. However, it is not limited to this, and component E may be located outside the battery pack 100. The evaluation value F is a parameter that indicates the degree of heat generation of component E. A larger evaluation value F indicates that heat generation is more dominant than heat dissipation in component E. The degree of heat generation of component E is proportional to the square of the current value flowing through component E. Also, the degree of heat dissipation from component E can be approximated by a first-order lag system. The ECU 500 may obtain the evaluation value F by applying a first-order lag process to the square of the current value of component E. Specifically, the ECU 500 may calculate the evaluation value F according to the following formula. The calculated evaluation value F is stored in the memory device 520.

[0033] F(n+1) = {(K(n)-1) × F(n) + IB(n)} 2} / K(n) In the above formula, n represents the number of calculations. n is a natural number, F(n+1) represents the evaluation value F for the current (n+1th) calculation, and F(n) represents the evaluation value F for the previous (nth) calculation. Note that the evaluation value F is also calculated in circuit mode (see S31 in Figure 4, described later). The calculation history of the evaluation value F is shared between S21 in Figure 3 and S31 in Figure 4, and the number of calculations is incremented regardless of which step the calculation is performed in. The product of the calculation period and the number of calculations (n) corresponds to the elapsed time since the first calculation. The calculation period of the ECU 500 may be around 100 milliseconds. The initial value of the evaluation value F may be stored in the memory device 520 beforehand. IB(n) represents the current value flowing through component E when the number of calculations is n. K(n) represents the coefficient for performing a first-order lag approximation, i.e., the coefficient corresponding to the time constant (annealing constant). K(n) is a constant greater than or equal to 1, and the smaller K(n) is, the greater the increase in F(n+1) per unit time. Different values ​​may be set for the coefficient K(n) when the current is increasing and when it is decreasing.

[0034] The method for calculating the evaluation value F is not limited to the above and is arbitrary. For example, the ECU500 may obtain the evaluation value F using a trained model. The trained model may be generated by machine learning using AI (artificial intelligence). The trained model may be trained to output the evaluation value F of component E when data showing the current transition of component E is input.

[0035] In the subsequent S22, the ECU 500 sets Win using the evaluation value F of component E. For example, the ECU 500 sets Win higher when the evaluation value F is below a first threshold than when the evaluation value F exceeds the first threshold. The ECU 500 may also lower Win as the evaluation value F increases. The ECU 500 may also set Win based on a first map showing the relationship between the evaluation value F of component E and Win. The first map may be pre-stored in the memory device 520. However, the Win set in S22 is greater than 0W. The lower Win, the stricter the input limit becomes, and the smaller the maximum power that can be input to the battery pack 100. The input limit suppresses heat generation of component E. On the other hand, the input limit reduces energy recovery efficiency and regenerative braking force. As long as Win is greater than 0W, power input to the battery pack 100 is not completely prohibited and is permitted as long as it does not exceed Win.

[0036] In the subsequent S23, the ECU 500 sets Wout using the evaluation value F of component E. For example, the ECU 500 sets the Wout higher when the evaluation value F is below the second threshold than when the evaluation value F exceeds the second threshold. The ECU 500 may also lower Wout as the evaluation value F increases. The ECU 500 may also set Wout based on a second map showing the relationship between the evaluation value F of component E and Wout. The second map may be stored in the memory device 520 in advance. However, the Wout set in S23 is greater than 0W. The lower the Wout, the stricter the output limit becomes, and the smaller the maximum power that the battery pack 100 can output. The output limit suppresses the heat generation of component E. On the other hand, the output limit reduces the driving performance (especially acceleration performance) of the vehicle 1000. As long as Wout is greater than 0W, the output of power from the battery pack 100 is not completely prohibited and is permitted as long as it does not exceed Wout. The first threshold and the second threshold may be the same or different.

[0037] In the subsequent S24, the ECU500 performs charge and discharge control of the battery stack (each cell 10 included in the battery pack 100) based on the Win and Wout settings described above. For example, when the MG22 is in the powering state, discharge control of the battery stack is performed. In this discharge control, the ECU500 controls the PCU21 so that the output power of the battery pack 100 does not exceed Wout. In this way, while the battery stack is discharging, the output power of the battery pack 100 is limited so as not to exceed Wout. When the MG22 is in the regenerative state, charge control of the battery stack is performed. In this charge control, the ECU500 controls the PCU21 so that the input power of the battery pack 100 does not exceed Win. In this way, while the battery stack is charging, the input power of the battery pack 100 is limited so as not to exceed Win.

[0038] In the following step S25, the ECU 500 determines whether or not the vehicle 1000 has finished running in normal mode. If the vehicle 1000 is still running in normal mode (NO in S25), the process returns to the first step (S21). On the other hand, if the circuit mode is set by the process in S14 in Figure 2, the result in S25 is YES. Also, if the vehicle 1000 enters the Ready-OFF state due to the OFF operation of the start switch, the result in S25 is YES. If the result in S25 is YES, the processing flow F2 ends. However, if the circuit mode is set by the process in S14 in Figure 2, the processing flow F3 shown in Figure 4, which will be explained below, starts after the end of processing flow F2. Furthermore, during the period when the vehicle 1000's driving mode is circuit mode, the ECU 500 executes driving control of the vehicle 1000 corresponding to the circuit mode in response to manual driving by the user. Processing flow F3 is executed in parallel with the aforementioned processing flow F1 (Figure 2) and the circuit mode driving control (not shown).

[0039] Figure 4 is a flowchart showing the charge and discharge control of the battery pack 100 in circuit mode. In processing flow F3, the ECU 500 determines the evaluation value F of component E in S31. The method for calculating the evaluation value F is the same as in S21 in Figure 3. As a result, the evaluation value F of component E stored in the memory device 520 is updated.

[0040] In the following S32, the ECU 500 determines whether the braking force of the vehicle 1000 is insufficient. For example, if the accelerator operation on the driver's control panel is released, or if the brake is applied to the driver's control panel, the ECU 500 performs deceleration control of the vehicle 1000. In circuit mode, Win is basically set to 0W by the process in S33 described later, and regenerative braking is disabled. Therefore, deceleration of the vehicle 1000 is basically performed by the braking device 30 and / or engine braking. The ECU 500 may also determine whether the braking force of the vehicle 1000 is sufficient based on whether it can secure the braking force requested by the user through the driver's control panel (for example, the braking force corresponding to the amount of brake operation) without regenerative braking. Furthermore, during deceleration control of the vehicle 1000, the ECU 500 may determine that the braking force of the vehicle 1000 is insufficient if the braking force of the braking device 30 decreases due to heat generation or the like. During acceleration control of vehicle 1000, braking force is not required, therefore it is determined that there is no shortage of braking force.

[0041] If it is determined that the braking force of vehicle 1000 is sufficient (NO in S32), ECU 500 sets Win to 0W in S33. This prohibits power input to battery pack 100. As a result, charging of the battery stack by regenerative power is prohibited, and regenerative braking is also prohibited. Thus, in circuit mode, stricter input restrictions are implemented than in normal mode (see S22 in Figure 3).

[0042] In the following S34, the ECU 500 sets Wout, corresponding to the evaluation value F of component E, by referring to, for example, the second map, similar to S23 in Figure 3 mentioned above. Subsequently, in S35, the ECU 500 performs charge and discharge control of the battery stack (each cell 10 included in the battery pack 100) based on the Win and Wout set as described above. The charge and discharge control in S35 is also basically performed in a manner similar to S24 in Figure 3 mentioned above. However, in circuit mode, when the MG22 is in the regenerative state, the heat generation of component E is suppressed by a stricter input limit (input limit based on Win set in S33) than in normal mode. For this reason, in circuit mode, the output limit when the MG22 is in the powering state (output limit based on Wout set in S34) is looser than in normal mode. For example, Wout will be higher in circuit mode than in normal mode. Alternatively, the output limit of the battery pack 100 will be less likely to be executed in circuit mode. More specifically, the frequency of output limiting in circuit mode will be lower than the frequency of output limiting in normal mode. In circuit mode, the power limiting mechanism intervenes later than in normal mode. This results in improved driving performance (especially acceleration) in circuit mode.

[0043] Once process S35 is executed, the process proceeds to S36. In S36, ECU 500 determines whether or not vehicle 1000 has finished running in circuit mode. If vehicle 1000 is still running in circuit mode (NO in S36), the process returns to the first step (S31). In circuit mode, as long as vehicle 1000 continues to run without insufficient braking force, with Win set to 0W by process S33, processes S31 to S36 are repeatedly executed.

[0044] If braking force is insufficient during the driving of vehicle 1000 in circuit mode (YES in S32), ECU 500 determines in S37 whether the evaluation value F is lower than a predetermined reference value (hereinafter referred to as "Th"). If the evaluation value F is lower than Th (YES in S37), ECU 500, in S38, sets Win corresponding to the evaluation value F of component E by referring to, for example, the first map, similar to S22 in Figure 3 described above. As a result, Win becomes greater than 0W, the prohibition on charging the battery stack by regenerative power is lifted, and the prohibition on regenerative braking is also lifted. Therefore, the insufficient braking force can be compensated for by regenerative braking. If the evaluation value F obtained in S31 is sufficiently low, even if Win is set to a value greater than 0W, as in normal mode, an excessive temperature rise of component E will not occur. Th may be a boundary value that determines whether an excessive temperature rise of component E occurs by setting Win to a value greater than 0W (i.e., lifting the prohibition on charging the battery stack by regenerative power), as in normal mode. If the evaluation value F is greater than or equal to Th (NO in S37), ECU500 sets Win to 0W in S39. Once Win is set by the processing in S38 or S39, the process proceeds to S34.

[0045] If the normal mode is set by the process in S13 of Figure 2, the result in S36 is YES. Also, if the vehicle 1000 enters the Ready-OFF state by turning the start switch OFF, the result in S36 is YES. If the result in S36 is YES, the processing flow F3 ends. However, if the normal mode is set by the process in S13 of Figure 2, the aforementioned processing flow F2 (Figure 3) starts after the end of processing flow F3.

[0046] As described above, the vehicle 1000 according to this embodiment comprises a battery pack 100 (energy storage device), an MG22, a component E energized by the battery pack 100, and an ECU 500 (control device). The MG22 is configured to drive the vehicle 1000 with power output from the battery pack 100 in the powered state, and to charge the battery pack 100 with the regenerated power generated in the regenerative state. The ECU 500 is configured to perform input and output limits on the battery pack 100 in order to suppress heat generation of the component in both the normal mode (first driving mode) and the circuit mode (second driving mode) (S24 in Figure 3 and S35 in Figure 4). In the circuit mode, the ECU 500 is configured to perform stricter input limits on the battery pack 100 than in the normal mode (S33, S39 in Figure 4).

[0047] In the vehicle 1000 having the above configuration, in circuit mode, a stricter input limit is imposed on the battery pack 100 than in normal mode, thereby suppressing heat generation in component E. As a result, in circuit mode, the output limit when the MG22 is in a powered state is looser than in normal mode. This improves driving performance (especially acceleration performance) in circuit mode. Thus, with the above configuration, it is possible to protect the components energized by the energy storage device while increasing the vehicle driving force provided by the energy storage device as needed. The looser the output limit of the energy storage device, the higher the vehicle driving force provided by the energy storage device.

[0048] Automobiles have evolved remarkably in recent years, and in the future, there may be a demand for automobiles that can be used for both normal driving (driving for transportation) and circuit driving (driving for racing). In this regard, the vehicle 1000 described above is configured to be able to be driven in both normal mode and circuit mode. By changing the driving mode, the vehicle 1000 can perform appropriate driving control in both normal driving and circuit driving. For example, the input limit of the battery pack 100 tends to shorten the driving range of the vehicle 1000. In normal driving, driving range is given priority as much as or even more than driving performance. On the other hand, in circuit driving, driving performance (especially acceleration performance) is given priority over driving range. Therefore, the vehicle 1000 suppresses the heat generation of component E by limiting the regenerative power during circuit driving, and reduces the frequency of output limiting of the battery pack 100 (S33, S39 in Figure 4). This control makes it easier to secure the output power required for circuit driving. The above control makes it easier to implement appropriate input / output limits for the energy storage device for both normal driving and circuit driving.

[0049] In the above embodiment, when the vehicle 1000 is located within a circuit, the ECU 500 sets the vehicle 1000's driving mode to circuit mode. This makes it easier for the vehicle 1000's driving mode to be changed appropriately. In addition, it eliminates the need for the user to change the driving mode, thus improving user convenience.

[0050] In the above embodiment, the ECU 500 prohibits charging of the battery pack 100 by regenerative power by setting the upper limit of the regenerative power input to the battery pack 100 (Win) to 0W in circuit mode (S33, S39 in Figure 4). As a result, Wout in circuit mode tends to be higher than Wout in normal mode. However, it is not limited to this, and the ECU 500 may set Win to a value higher than 0W and lower than the Win value shown in the first map mentioned above in each of S33 and S39 in Figure 4. For example, a circuit map showing a Win value lower than the first map for the same evaluation value F may be stored in the storage device 520. The ECU 500 may set Win using the circuit map in each of S33 and S39 in Figure 4, or it may set Win to a value close to 0W.

[0051] In the above embodiment, the ECU 500 releases the prohibition on charging the battery pack 100 by regenerative power when the degree of heat generated by component E is lower than a reference value (Th) when the braking force of the vehicle 1000 is insufficient in circuit mode (S38 in Figure 4). This makes it possible to protect component E, which is energized by the battery pack 100, while applying braking force to the vehicle 1000 by regenerative braking as needed. However, it is not limited to this, and the ECU 500 may always prohibit charging the battery pack 100 by regenerative power in circuit mode.

[0052] Figure 5 is a flowchart showing a modified version of the process shown in Figure 4. The ECU 500 may execute the process flow F3A shown in Figure 5 instead of the process flow F3 shown in Figure 4. Process flow F3A is the same as process flow F3 except that steps S32 and S37-S39 (Figure 4) are omitted. According to process flow F3A, in circuit mode, processes S31 and S33-S36 are repeatedly executed. In this way, the ECU 500 may maintain Win at 0W in circuit mode.

[0053] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of the present invention is indicated by the claims rather than by the description of the embodiments above, and all modifications within the meaning and scope equivalent to the claims are intended to be included. [Explanation of Symbols]

[0054] 100 battery packs, 500 ECUs, 1000 vehicles, E parts.

Claims

1. A vehicle comprising a power storage device, a motor generator, a component energized by the power storage device, and a control device, The motor generator is configured to drive the vehicle with power output from the energy storage device during powering, and to charge the energy storage device with the regenerated power generated during regeneration. The control device is configured to perform input and output limits on the energy storage device in each of the first and second driving modes to suppress heat generation from the components. A vehicle in which the control device is configured to implement a stricter input limit on the energy storage device in the second driving mode than the input limit on the energy storage device in the first driving mode.

2. The vehicle according to claim 1, wherein the second driving mode is a driving mode more suitable for circuit driving than the first driving mode.

3. The vehicle according to claim 1, wherein the control device sets the vehicle's driving mode to the second driving mode when the vehicle is located within a circuit.

4. The vehicle according to any one of claims 1 to 3, wherein the control device is configured to prohibit charging of the energy storage device by regenerative power in the second driving mode by setting the upper limit of the regenerative power input to the energy storage device to 0W.

5. The vehicle according to claim 4, wherein the control device is configured to release the prohibition on charging when the degree of heat generation of the component is lower than a reference value when the braking force of the vehicle is insufficient in the second driving mode.

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