Vehicle control device

Abstract

To provide a technique that can reduce a possibility that a temperature of a power semiconductor unit increases excessively, so that regenerative braking cannot be performed satisfactorily.SOLUTION: A control device of a vehicle comprises a brake control part that controls regenerative braking using a power semiconductor unit, and a temperature monitoring part that monitors, as a monitored temperature, a temperature of a refrigerant for cooling the power semiconductor unit or a temperature of the power semiconductor unit. The brake control part executes braking control in a specific regenerative braking mode, in which when the monitored temperature becomes equal to a first threshold temperature or higher (1), a first deceleration restriction is applied and when the monitored temperature becomes less than a second threshold temperature lower than the first threshold temperature (2), the deceleration restriction is eased more than the first deceleration restriction, for the regenerative braking.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a control device for a vehicle that performs regenerative braking. [Background technology]

[0002] Patent Document 1 discloses a technology for correcting deceleration in accordance with the pedal operation amount in a vehicle that can be driven in one-pedal mode, so that the driver's intention is appropriately reflected in the deceleration. When an electric motor is used as a driving force source for the vehicle, regenerative braking can be used. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2020-100349 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the conventional technology has a problem in that the temperature of the power semiconductor unit used for regenerative braking of the electric motor may rise excessively, making it impossible to perform sufficient regenerative braking. [Means for solving the problem]

[0005] According to one embodiment of the present disclosure, there is provided a vehicle control device. The control device includes a brake control unit that controls regenerative braking using a power semiconductor unit, and a temperature monitoring unit that monitors the temperature of a coolant that cools the power semiconductor unit or the temperature of the power semiconductor unit as a monitored temperature. The brake control unit (i) applies a first deceleration limit when the monitored temperature is equal to or higher than a first threshold temperature, and (ii) performs braking control in a specific regenerative braking mode, in which the deceleration limit is weaker than the first deceleration limit when the monitored temperature is lower than a second threshold temperature that is lower than the first threshold temperature. and (iii) in the specific regenerative braking mode, when the monitored temperature becomes equal to or higher than the second threshold temperature before becoming the first threshold temperature, maintain the deceleration limit in its previous state. The brake control unit has one or more regenerative boost modes that apply the regenerative braking more strongly than a normal driving mode as a driving mode of the vehicle selected by a driving mode selection unit including a shift lever, and the brake control unit executes braking control using the specific regenerative braking mode when a strongest mode that applies the regenerative braking most strongly is selected from the one or more regenerative boost modes. .

[0006] According to the control device, the first deceleration limit is applied when the monitored temperature is equal to or higher than the first threshold temperature, thereby reducing the possibility that the temperature of the power semiconductor unit will rise sharply and that sufficient regenerative braking will not be possible. Also, when the monitored temperature is lower than the second threshold temperature, the deceleration limit is weakened, thereby enabling sufficient regenerative braking. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is an explanatory diagram showing the configuration of a vehicle. [Figure 2] 6 is a flowchart showing a processing procedure in a specific regenerative braking mode. [Figure 3] 5 is a timing chart showing an example of operation in a specific regenerative braking mode. DETAILED DESCRIPTION OF THE INVENTION

[0008] 1 is an explanatory diagram showing the configuration of a vehicle 100 according to an embodiment. The vehicle 100 includes a main battery 10, a system main relay 20, a power control unit 30, a drive mechanism 40 that drives wheels 50, a cooling system 60 that cools the power control unit 30, a control device 70, sensors 80, and a driving mode selection unit 90.

[0009] The drive mechanism 40 includes an engine 41, which is an internal combustion engine for driving the wheels, an electric motor 42 for driving the wheels, and a generator 43 that mainly functions as a power generator. The engine 41, the electric motor 42, and the generator 43 are connected by a power split mechanism 44. The power split by the power split mechanism 44 is transmitted to a drive shaft 46 via a gear train 45, causing the wheels 50 to rotate.

[0010] The vehicle 100 of this embodiment is a hybrid vehicle having two drive sources, an engine 41 and an electric motor 42. However, the vehicle 100 may be a hybrid vehicle having a configuration different from that shown in Fig. 1. The present disclosure is also applicable to an electric vehicle using only the electric motor 42 as a drive source.

[0011] The main battery 10 and the power control unit 30 are connected by DC wiring 22. The system main relay 20 is installed between the main battery 10 and the power control unit 30. The main battery 10 is a secondary battery that stores power for running the vehicle, i.e., power for the electric motor 42.

[0012] The power control unit 30 includes a DC / DC converter 31, an inverter 32 for the electric motor 42, and an inverter 33 for the generator 43. The DC / DC converter 31 is a boost converter that boosts the voltage of DC power provided by the main battery 10 and supplies it to the inverters 32 and 33. The inverters 32 and 33 are power conversion devices that convert DC power to AC power and vice versa. The inverter 32 for the electric motor 42 also functions as a regenerative inverter that converts regenerative power generated by the electric motor 42 from AC power to DC power during regenerative braking of the vehicle 100. The voltage of the regenerative DC power converted by the inverter 32 is adjusted by the DC / DC converter 31 and charged to the main battery 10. The temperature Tp of the power control unit 30 is measured by a temperature sensor 34. The temperature sensor 34 can be installed at any position in the power control unit 30. However, it is preferable to install multiple temperature sensors 34 to measure the temperatures of individual power semiconductor elements.

[0013] The DC / DC converter 31 and the two inverters 32, 33 are configured as a circuit having a plurality of power semiconductor elements such as IGBTs (Insulated Gate Bipolar Transistors). The power control unit 30 corresponds to the "power semiconductor unit" of the present disclosure. The "power semiconductor unit" of the present disclosure preferably includes at least the regenerative inverter 32.

[0014] The cooling system 60 has a radiator 61, a pump 62, and a circulation pipe 63, and uses a coolant CL to cool the power control unit 30. The coolant CL is a liquid and is also called "cooling water." The circulation pipe 63 is installed to cool the multiple power semiconductor elements included in the power control unit 30, but is depicted in a simplified manner in FIG. 1. The coolant temperature Tc of the coolant CL is measured by a temperature sensor 64. The temperature sensor 64 is preferably installed at the outlet position of the power control unit 30 in the path of the circulation pipe 63.

[0015] The control device 70 includes a drive control unit 71, a brake control unit 72, and a temperature monitoring unit 73. The drive control unit 71 executes drive control to drive the wheels 50 using the drive mechanism 40. The brake control unit 72 executes braking control to brake the wheels 50. The temperature monitoring unit 73 monitors the refrigerant temperature Tc measured by the temperature sensor 64 and the temperature Tp of the power control unit 30 measured by the temperature sensor 34. These temperatures Tc and Tp are used as monitored temperatures to control the power control unit 30 to prevent it from overheating.

[0016] The control device 70 can be configured using one or more ECUs (Electronic Control Units). The functions of the control device 70 can be realized by a processor executing a computer program stored in a non-volatile storage medium. Note that some of the functions of the control device 70 may be realized by a hardware circuit.

[0017] The brake control unit 72 determines a required braking force to be applied to the entire vehicle based on the brake pedal operation amount detected by the brake operation amount sensor 81, the accelerator pedal operation amount detected by the accelerator operation amount sensor 82, and the driving mode selected by the driving mode selection unit 90. A method for selecting a driving mode using the driving mode selection unit 90 will be described later. The brake control unit 72 further decomposes the required braking force into a target regenerative braking force due to regenerative braking of the electric motor 42 and a target mechanical braking force due to braking of the mechanical brake system. Furthermore, the brake control unit 72 controls the power control unit 30 to realize the target regenerative braking force, and controls the mechanical brake system to realize the target mechanical braking force.

[0018] When the accelerator pedal depression amount changes from a non-zero state to zero while the vehicle 100 is running, and the brake pedal depression amount also becomes zero, regenerative braking using only the regenerative braking force is performed. In this regenerative braking, the brake control unit 72 sets a target regenerative braking force and controls the power control unit 30.

[0019] The driving mode selection unit 90 is an operating means operated by the driver to set the driving mode of the vehicle 100, and includes a shift lever 91 and a regenerative boost selection unit 92. The shift lever 91 has four shift ranges: P (Parking), R (Rear), N (Neutral), and D (Drive). The shift range selected by the shift lever 91 is detected by a shift position sensor 83 and notified to the control device 70. The regenerative boost selection unit 92 is a button for specifying a regenerative boost mode. The regenerative boost mode is a mode in which regenerative braking is applied more strongly when the accelerator pedal is released. In this embodiment, the driver can arbitrarily select one of three regenerative boost modes: "strong," "medium," or "weak." The "strong" regenerative boost mode is the mode in which regenerative braking is strongest among the three regenerative boost modes, and the "weak" regenerative boost mode is the mode in which regenerative braking is weakest among the three regenerative boost modes. The regenerative boost mode may have only one option. That is, it is preferable that the regenerative boost selection unit 92 is configured so that at least one mode can be selected as the regenerative boost mode. The regenerative boost selection unit 92 is displayed, for example, on a touch panel that can be operated by the driver.

[0020] When the D range is selected by the shift lever 91 and the regenerative boost mode is not selected, the vehicle 100 is controlled in the normal driving mode. On the other hand, when the D range is selected by the shift lever 91 and the regenerative boost mode is selected, the vehicle 100 is controlled in the selected regenerative boost mode.

[0021] It should be noted that the shift lever 91 may be provided with other ranges, such as a B (Brake) range. When the B range is selected, stronger regenerative braking is performed than in the D range used during normal driving. The driving mode when such a range that performs stronger regenerative braking is selected is also a type of "regenerative boost mode" of the present disclosure.

[0022] FIG. 2 is a flowchart showing the processing procedure in the specific regenerative braking mode, and FIG. 3 is a timing chart showing an example of operation in the specific regenerative braking mode. The "specific regenerative braking mode" is a mode in which strong regenerative braking is permitted. In this embodiment, when the "strong" or "medium" regenerative boost mode is selected, braking control in the specific regenerative braking mode, which will be described below, is executed. On the other hand, in the normal driving mode or when the "weak" regenerative boost mode is selected, braking control in the specific regenerative braking mode is not executed.

[0023] Braking control in the specific regenerative braking mode may be performed even when the "weak" regenerative boost mode is selected. Alternatively, braking control in the specific regenerative braking mode may not be performed when the "medium" regenerative boost mode is selected. In this way, it is preferable that braking control in the specific regenerative braking mode be performed at least when the "strong" regenerative boost mode is selected.

[0024] 2 and 3, it is assumed that the "strong" regenerative boost mode is selected. It is also assumed that the accelerator pedal depression amount changes from a non-zero state to zero while the vehicle 100 is running, and that the brake pedal depression amount also becomes zero. Therefore, in the process of FIG. 2, braking is performed using only regenerative braking force. The process of FIG. 2 is also periodically repeated. Note that although the refrigerant temperature Tc is used as the monitored temperature in FIGS. 2 and 3, the temperature Tp of the power control unit 30 may be used as the monitored temperature instead of the refrigerant temperature Tc.

[0025] In step S10, the brake control unit 72 determines whether the refrigerant temperature Tc is equal to or greater than a first threshold temperature T1, and in step S20, determines whether the refrigerant temperature Tc is equal to or greater than a second threshold temperature T2. In other words, in steps S10 and S20, it is determined whether the refrigerant temperature Tc is in one of the following three states: (1) High temperature state: T1≦Tc (2) Intermediate state: T2≦Tc <T1 (3) Low temperature state: Tc <T2

[0026] When the refrigerant temperature Tc is in a high temperature state, that is, equal to or higher than the first threshold temperature T1, the brake control unit 72 sets the deceleration limit to "strong" in step S30. Specifically, the deceleration of the vehicle 100 obtained by regenerative braking is limited to equal to or lower than a first upper limit deceleration Lα1. The first threshold temperature T1 is set, for example, as a temperature at which there is no risk of applying a load factor limit on the power control unit 30. That is, when the refrigerant temperature Tc is lower than the first threshold temperature T1, the temperature of the power semiconductor elements is sufficiently low, so there is no risk of applying a load factor limit on the power control unit 30 even if the deceleration is not limited to equal to or lower than the first upper limit deceleration Lα1. Conversely, when the refrigerant temperature Tc is in a high temperature state, that is, equal to or higher than the first threshold temperature T1, there is a possibility that the power semiconductor elements will overheat and a load factor limit will be applied to the power control unit 30, so it is preferable to limit the deceleration of the vehicle 100 to equal to or lower than the first upper limit deceleration Lα1. Whether or not to apply a load rate limit to the power control unit 30 can be determined based on the result of comparing the temperature Tp of the power control unit 30 measured by the temperature sensor 34 with a preset threshold. If a load rate limit is applied to the power control unit 30, the regenerative braking force will suddenly decrease, and the deceleration rate α will also suddenly decrease, which may cause the occupants to feel uncomfortable or scared. If the refrigerant temperature Tc is in a high temperature state in step S10, where the refrigerant temperature Tc is equal to or higher than the first threshold temperature T1, setting the deceleration rate limit to "strong" in step S30 can reduce the possibility that the temperature of the power control unit 30 will rise excessively, making it impossible to perform sufficient regenerative braking. In addition, it can reduce the possibility that the deceleration rate α will suddenly decrease, causing the occupants to feel uncomfortable or scared.

[0027] If the coolant temperature Tc is in an intermediate state where it is equal to or higher than the second threshold temperature T2 and lower than the first threshold temperature T1, the brake control unit 72 maintains the previous deceleration limit in step S40. An example of this will be described later.

[0028] If the refrigerant temperature Tc is in a low-temperature state where it is less than the second threshold temperature T2, then in step S50, the brake control unit 72 sets the deceleration limit to "weak." In other words, the deceleration of the vehicle 100 obtained by regenerative braking is limited to a second upper limit deceleration Lα2 or less, which is greater than the first upper limit deceleration Lα1. The second threshold temperature T2 is set to a temperature at which the refrigerant temperature Tc is unlikely to reach or exceed the first threshold temperature T1, even if the second upper limit deceleration Lα2, which is greater than the first upper limit deceleration Lα1, is applied. Setting the second threshold temperature T2 to a value sufficiently lower than the first threshold temperature T1 reduces the possibility that the deceleration limit will be frequently switched between "strong" and "weak," resulting in unstable braking control.

[0029] Note that when the refrigerant temperature Tc is in a low temperature state where it is less than the second threshold temperature T2, instead of applying the second upper limit deceleration Lα2, no deceleration limitation may be performed. In this way, stronger regenerative braking can be performed. As can be seen from this example, when the refrigerant temperature Tc is less than the second threshold temperature T2, it is preferable to weaken the deceleration limitation compared to when the refrigerant temperature Tc is equal to or greater than the first threshold temperature T1. The phrase "weakening the deceleration limitation" is used in a broad sense to encompass both the case where the second upper limit deceleration Lα2, which is greater than the first upper limit deceleration Lα1, is applied, and the case where no deceleration limitation is performed.

[0030] In step S60, the brake control unit 72 adjusts the deceleration α while ensuring jerk in accordance with the target deceleration and the deceleration limit. The "target deceleration" is the deceleration corresponding to the target regenerative braking force. The "jerk" is the rate of change Δα [m / s 3 ], that is, the change in deceleration α per unit time. Furthermore, "ensuring jerk" means changing the deceleration α at a rate of change Δα that is equal to or less than a preset upper limit rate of change Δmax. The jerk limit is applied in priority to the deceleration limit. By changing the deceleration α at a rate of change Δα that is equal to or less than the upper limit rate of change Δmax, it is possible to adjust the deceleration α without causing discomfort or fear to the occupants while preventing overheating of the power control unit 30.

[0031] FIG. 3 shows an example of changes in refrigerant temperature Tc, the strength / weakness of the deceleration limit, the deceleration α, and the upper limit deceleration Lα. Before time t1, the refrigerant temperature Tc is less than the second threshold temperature T2, so the deceleration limit is set to "weak," and the second upper limit deceleration Lα2 is applied. In the example of FIG. 3, the target deceleration αt is set to a value smaller than the second upper limit deceleration Lα2. Therefore, the actual deceleration α is also equal to the target deceleration αt. As described above, when the refrigerant temperature Tc is less than the second threshold temperature T2, no deceleration limit may be applied.

[0032] During the period from time t1 to time t2, the refrigerant temperature Tc is equal to or higher than the second threshold temperature T2 and lower than the first threshold temperature T1, so the deceleration limit is maintained at the same level as before time t1, and the actual deceleration α is maintained at a value equal to the target deceleration αt.

[0033] During the period from time t2 to time t3, the refrigerant temperature Tc is equal to or higher than the first threshold temperature T1, so the deceleration limit is set to "strong" and the first upper limit deceleration Lα1 is applied. Therefore, the actual deceleration α is limited to a value equal to or lower than the first upper limit deceleration Lα1. Furthermore, the rate of change Δα of the deceleration α is limited to be equal to or lower than the upper limit change rate Δmax. This limit on the rate of change Δα is applied with priority over the deceleration limit. In the example of FIG. 3, the rate of change Δα of the deceleration α is set equal to the upper limit change rate Δmax. Therefore, during the period from time t2 onwards, the deceleration α decreases from the target deceleration αt to the first upper limit deceleration Lα1 while changing at the upper limit change rate Δmax. The reason for limiting the rate of change Δα of the deceleration α to be equal to or lower than the upper limit change rate Δmax is to prevent a sudden change in the deceleration α from causing discomfort or fear to the occupants of the vehicle 100.

[0034] During the period from time t3 to time t4, the refrigerant temperature Tc is equal to or higher than the second threshold temperature T2 and lower than the first threshold temperature T1, so the deceleration limit is maintained the same as before time t3, and the first upper limit deceleration Lα1 is applied.

[0035] After time t4, the refrigerant temperature Tc becomes less than the second threshold temperature T2, so the deceleration limit is set to "weak" and the second upper limit deceleration Lα2 is applied. The rate of change Δα of the deceleration α is also limited to be equal to or less than the upper limit change rate Δmax. In the example of FIG. 3, the rate of change Δα of the deceleration α is set equal to the upper limit change rate Δmax. Therefore, during the period after time t4, the deceleration α increases from the first upper limit deceleration Lα1 to the target deceleration αt while changing at the upper limit change rate Δmax.

[0036] 2 and 3, the regenerative control in the specific regenerative braking mode can reduce the possibility that the temperature of the power control unit 30 will rise excessively, preventing sufficient regenerative braking. Also, since the deceleration α is changed at a rate equal to or less than the upper limit change rate Δmax, it is possible to prevent the occupants from feeling uncomfortable or scared.

[0037] The specific regenerative braking mode described above is applied when the regenerative boost mode is selected by the regenerative boost selection unit 92, but it may also be applied when the regenerative boost mode is not selected. However, if the specific regenerative braking mode is applied when the regenerative boost mode is selected, strong regenerative braking can be achieved without overheating the power control unit 30. The specific regenerative braking mode may also be applied when the brake pedal is depressed and both mechanical braking force and regenerative braking force are used. In this case, the insufficient braking force of the target regenerative braking force that cannot be achieved due to the deceleration limit related to regenerative braking is supplemented by mechanical braking force.

[0038] In the above-described embodiment, the deceleration limit is increased when the coolant temperature Tc is equal to or greater than the first threshold temperature T1, thereby reducing the possibility that the temperature of the power control unit 30 will rise excessively and that sufficient regenerative braking will not be possible. Furthermore, the deceleration limit is decreased when the coolant temperature Tc is less than the second threshold temperature T2, thereby enabling sufficient regenerative braking. In the above-described embodiment, the coolant temperature Tc is used as the monitored temperature, but the temperature Tp of the power control unit 30 may be used as the monitored temperature instead of the coolant temperature Tc. However, using the coolant temperature Tc as the monitored temperature has the advantage of reducing the possibility of excessive deceleration limiting compared to using the temperature Tp of the power control unit 30 as the monitored temperature.

[0039] Other forms: The present disclosure is not limited to the above-described embodiments and can be realized in various forms without departing from the spirit thereof. For example, the present disclosure can also be realized in the following aspects. The technical features in the above embodiments corresponding to the technical features in each aspect described below can be appropriately replaced or combined to solve some or all of the problems of the present disclosure or to achieve some or all of the effects of the present disclosure. Furthermore, if a technical feature is not described as essential in this specification, it can be appropriately deleted.

[0040] (1) According to one aspect of the present disclosure, there is provided a control device for controlling a vehicle. The control device includes a brake control unit that controls regenerative braking using a power semiconductor unit, and a temperature monitoring unit that monitors the temperature of a coolant that cools the power semiconductor unit or the temperature of the power semiconductor unit as a monitored temperature. The brake control unit executes braking control using a specific regenerative braking mode for the regenerative braking, (i) applying a first deceleration limit when the monitored temperature is equal to or greater than a first threshold temperature, and (ii) weakening the deceleration limit below the first deceleration limit when the monitored temperature is less than a second threshold temperature that is lower than the first threshold temperature. According to this control device, the first deceleration limit is applied when the monitored temperature is equal to or higher than the first threshold temperature, thereby reducing the possibility that the temperature of the power semiconductor unit will rise excessively and sufficient regenerative braking will be impossible. Also, the deceleration limit is weakened when the monitored temperature is lower than the second threshold temperature, thereby enabling sufficient regenerative braking.

[0041] (2) In the control device, (ii) the brake control unit may not limit the deceleration when the monitored temperature becomes lower than the second threshold temperature. According to this control device, when the monitored temperature becomes lower than the second threshold temperature, the deceleration is not limited, so that stronger regenerative braking can be performed.

[0042] (3) In the control device, the temperature monitoring unit may monitor, as the monitored temperature, the temperature of the coolant that cools the power semiconductor unit. According to this control device, the possibility of excessively restricting the deceleration can be reduced compared to when the temperature of the power semiconductor unit is used as the monitored temperature.

[0043] (4) In the above control device, the front brake control unit may apply the first deceleration limit and limit the rate of change of the vehicle's deceleration to a predetermined upper limit rate of change or less when the monitored temperature becomes equal to or higher than the first threshold temperature during regenerative braking. According to this control device, by limiting the rate of change of the vehicle's deceleration to an upper limit rate of change or less, it is possible to prevent overheating of the power semiconductor unit and adjust the deceleration without causing discomfort or fear to the occupants.

[0044] (5) In the above control device, the brake control unit may have one or more regenerative boost modes that apply the regenerative braking more strongly than a normal driving mode as the driving mode of the vehicle selected by a driving mode selection unit including a shift lever, and the brake control unit may perform braking control using the specific regenerative braking mode when a strongest mode that applies the strongest regenerative braking is selected from the one or more regenerative boost modes. According to this control device, when the regenerative boost mode, which provides strong regenerative braking, is selected, strong regenerative braking can be achieved without overheating the power semiconductor unit by using the specific regenerative braking mode.

[0045] The present disclosure may be realized in various forms other than those described above, such as a vehicle equipped with a control device, a vehicle control method, a computer program for controlling the vehicle, a non-transitory storage medium on which the computer program is recorded, etc. [Explanation of symbols]

[0046] 10...Main battery, 20...System main relay, 22...DC wiring, 30...Power control unit, 31...DC / DC converter, 32...Inverter, 33...Inverter, 34...Temperature sensor, 40...Drive mechanism, 41...Engine, 42...Electric motor, 43...Generator, 44...Power split mechanism, 45...Gear train, 46...Drive shaft, 50...Wheels, 60...Cooling system, 61...Radiator, 62...Pump, 63...Circulation piping, 64...Temperature sensor, 70...Control device, 71...Drive control unit, 72...Brake control unit, 73...Temperature monitoring unit, 80...Sensors, 81...Brake operation amount sensor, 82...Accelerator operation amount sensor, 90...Driving mode selection unit, 91...Shift lever, 92...Regenerative boost selection unit, 100...Vehicle

Claims

1. A control device for controlling a vehicle, a brake control unit that controls regenerative braking using a power semiconductor unit; a temperature monitoring unit that monitors the temperature of a coolant that cools the power semiconductor unit or the temperature of the power semiconductor unit as a monitored temperature; Equipped with The brake control unit, with respect to the regenerative braking, (i) applies a first deceleration limit when the monitored temperature is equal to or higher than a first threshold temperature, (ii) executes braking control in a specific regenerative braking mode in which the deceleration limit is weakened to be lower than the first deceleration limit when the monitored temperature is lower than a second threshold temperature that is lower than the first threshold temperature, and (iii) in the specific regenerative braking mode, when the monitored temperature is equal to or higher than the second threshold temperature before becoming the first threshold temperature, maintains the deceleration limit in its previous state. the brake control unit has one or more regenerative boost modes that apply the regenerative braking more strongly than a normal driving mode, as a driving mode of the vehicle selected by a driving mode selection unit including a shift lever, The brake control unit executes braking control in the specific regenerative braking mode when a strongest mode in which the regenerative braking is strongest is selected from the one or more regenerative boost modes.

2. The control device according to claim 1, The brake control unit (ii) does not limit the deceleration when the monitored temperature becomes lower than the second threshold temperature.

3. The control device according to claim 1, The temperature monitoring unit monitors the temperature of the refrigerant that cools the power semiconductor unit as the monitored temperature.

4. The control device according to claim 1, The brake control unit applies the first deceleration limit and limits the rate of change of the vehicle's deceleration to a predetermined upper limit rate of change or less when the monitored temperature becomes equal to or higher than the first threshold temperature during regenerative braking.

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