Vehicle control device, vehicle control program, and vehicle control method

Abstract

To suppress a change in a braking force of a vehicle each time a filter temperature changes, while enabling regeneration processing in a strong regeneration mode to be performed.SOLUTION: A vehicle control device executes a combustion stop process to generate a braking force for a vehicle by engine braking, when deceleration is requested of the vehicle and a filter temperature is below a specified temperature as a necessary condition. The control device executes a combustion continuation process to burn fuel in cylinders when the deceleration is requested of the vehicle and the filter temperature is equal to or higher than the specified temperature. The control device executes a setting process to set one of a normal regeneration mode and a strong regeneration mode based on a request from the vehicle's driver. When the deceleration is requested of the vehicle, the control device executes a regeneration process to generate a braking force by a motor generator in one of the normal regeneration mode and the strong regeneration mode. When the filter temperature is equal to or higher than the specified temperature in the setting process, the control device sets the normal regeneration mode regardless of a request from the vehicle's driver (S52).SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a vehicle control device, a vehicle control program, and a vehicle control method. [Background technology]

[0002] The vehicle in Patent Document 1 includes an internal combustion engine, a motor generator, and a control device. The internal combustion engine and the motor generator are capable of transmitting power to the drive wheels of the vehicle. The control device controls the internal combustion engine and the motor generator based on factors such as the amount of accelerator pedal operation by the vehicle driver. The control device then executes regeneration processing when the amount of accelerator pedal operation is zero, i.e., when deceleration of the vehicle is requested. The regeneration processing is processing that generates braking force for the vehicle by operating the motor generator as a generator. When executing this regeneration processing, the control device generates braking force for the vehicle in one of a normal regeneration mode and a strong regeneration mode. The strong regeneration mode generates a braking force that is greater than that generated in the normal regeneration mode. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-112204 Summary of the Invention [Problem to be solved by the invention]

[0004] In a vehicle such as that described in Patent Document 1, when deceleration is required, not only is a regeneration process performed, but a combustion stop process may also be performed, in which fuel supply from the fuel injection valve to the cylinder is stopped and a braking force of the vehicle is generated by engine braking using the internal combustion engine. Therefore, in such a vehicle, the braking force of the vehicle generated by the internal combustion engine varies depending on whether the combustion stop process is performed. On the other hand, in a vehicle such as that described in Patent Document 1, the braking force of the vehicle generated by the motor generator varies depending on whether the normal regeneration mode or the strong regeneration mode is performed. However, Patent Document 1 does not pay any attention to which of the regeneration modes should be performed in relation to whether the combustion stop process is performed. [Means for solving the problem]

[0005] A vehicle control device for solving the above-mentioned problems is a control device that is applied to a vehicle that includes an internal combustion engine having a cylinder, which is a space for burning fuel, a fuel injection valve for supplying fuel into the cylinder, an exhaust passage connected to the cylinder, a catalyst located in the exhaust passage for purifying exhaust, a filter located in the exhaust passage downstream of the catalyst for capturing particulate matter contained in the exhaust, and a crankshaft that rotates based on the combustion of fuel in the cylinder and is capable of transmitting power to drive wheels, and a motor generator that is capable of transmitting power to the drive wheels, and the control device includes: a combustion stop process that generates a braking force on the vehicle by engine braking using the internal combustion engine while stopping the supply of fuel from the fuel injection valve to the cylinder, when deceleration is required in the vehicle and the filter temperature, which is the temperature of the filter, is lower than a predetermined specified temperature as a necessary condition; When deceleration is requested in the vehicle and the filter temperature is equal to or higher than the specified temperature, the system can execute the following: a combustion continuation process in which fuel is supplied from the fuel injection valve to the cylinder while burning fuel in the cylinder; a setting process in which, based on a request from the driver of the vehicle, selectively sets one of a normal regeneration mode in which the braking force is generated by operating the motor generator as a generator, and a strong regeneration mode in which the motor generator is operated as a generator so as to generate a braking force greater than that in the normal regeneration mode; and a regeneration process in which, when deceleration is requested in the vehicle, the braking force is generated in one of the normal regeneration mode and the strong regeneration mode set in the setting process. In the setting process, when the filter temperature is equal to or higher than the specified temperature, the normal regeneration mode is set from the normal regeneration mode and the strong regeneration mode regardless of the request from the driver of the vehicle.

[0006] A vehicle control program for solving the above-described problems is applied to a control device for a vehicle including an internal combustion engine having cylinders which are spaces for burning fuel, fuel injection valves for supplying fuel into the cylinders, an exhaust passage connected to the cylinders, a catalyst located in the exhaust passage for purifying exhaust, a filter located in the exhaust passage downstream of the catalyst for capturing particulate matter contained in the exhaust, and a crankshaft which rotates based on the combustion of fuel in the cylinders and is capable of transmitting power to drive wheels, and a motor generator capable of transmitting power to the drive wheels, and the control device is configured to perform a combustion stop process for generating a braking force on the vehicle by engine braking using the internal combustion engine while stopping the supply of fuel from the fuel injection valves to the cylinders, when deceleration of the vehicle is required and a filter temperature which is the temperature of the filter is lower than a predetermined specified temperature as necessary conditions; The system is capable of executing the following: a combustion continuation process in which, when deceleration is requested in the vehicle and the filter temperature is equal to or higher than the specified temperature, fuel is supplied from the fuel injection valve to the cylinder while fuel is burned in the cylinder; a setting process in which, based on a request from the driver of the vehicle, selectively sets one of a normal regeneration mode in which the braking force is generated by operating the motor generator as a generator, and a strong regeneration mode in which the motor generator is operated as a generator so as to generate a braking force greater than that in the normal regeneration mode; and a regeneration process in which, when deceleration is requested in the vehicle, the braking force is generated in one of the normal regeneration mode and the strong regeneration mode set in the setting process, and in which, when the filter temperature is equal to or higher than the specified temperature, the normal regeneration mode is set from the normal regeneration mode and the strong regeneration mode regardless of the request from the driver of the vehicle.

[0007] A vehicle control method for solving the above-mentioned problems is applied to a control device for a vehicle including an internal combustion engine having a cylinder, which is a space for burning fuel, a fuel injection valve for supplying fuel into the cylinder, an exhaust passage connected to the cylinder, a catalyst located in the exhaust passage for purifying exhaust, a filter located in the exhaust passage downstream of the catalyst for capturing particulate matter contained in the exhaust, and a crankshaft that rotates based on the combustion of fuel in the cylinder and is capable of transmitting power to drive wheels, and a motor generator capable of transmitting power to the drive wheels, wherein the control device performs a combustion stop process that generates a braking force on the vehicle by engine braking using the internal combustion engine while stopping the supply of fuel from the fuel injection valve to the cylinder, when deceleration is required of the vehicle and the filter temperature is lower than a predetermined specified temperature as a necessary condition; When deceleration is requested in the vehicle and the filter temperature is equal to or higher than the specified temperature, the system can execute the following: a combustion continuation process in which fuel is burned in the cylinder while supplying fuel from the fuel injection valve to the cylinder; a setting process in which, based on a request from the driver of the vehicle, selectively sets one of a normal regeneration mode in which the braking force is generated by operating the motor generator as a generator, and a strong regeneration mode in which the motor generator is operated as a generator so as to generate a braking force greater than that in the normal regeneration mode; and a regeneration process in which, when deceleration is requested in the vehicle, the braking force is generated in one of the normal regeneration mode and the strong regeneration mode set in the setting process. In the setting process, when the filter temperature is equal to or higher than the specified temperature, the normal regeneration mode is set from the normal regeneration mode and the strong regeneration mode regardless of the request from the driver of the vehicle. [Effects of the Invention]

[0008] According to the above configuration, for example, if the filter temperature exceeds a predetermined temperature while the vehicle is traveling, the normal regeneration mode is subsequently set. In this normal regeneration mode, the braking force generated by the motor-generator is smaller than in the strong regeneration mode, allowing for increased braking force. For example, suppose that the vehicle is requested to decelerate and a combustion continuation process is executed. Since the normal regeneration mode is set, even if the braking force generated by the internal combustion engine is reduced due to the inability to perform a combustion stop process, the braking force generated by the motor-generator can be increased to compensate for the reduced braking force generated by the internal combustion engine. Therefore, even if the magnitude of the braking force generated by the internal combustion engine changes in response to a change in filter temperature, the sum of the braking forces generated by the internal combustion engine and the motor-generator is prevented from changing with each change in filter temperature. As a result, while enabling regeneration in the strong regeneration mode, it is possible to prevent a situation in which the vehicle's braking force changes with each change in filter temperature due to the strong regeneration mode being set. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram of a vehicle. [Figure 2] FIG. 2 is a flowchart showing the first switching control. [Figure 3] FIG. 3 is a flowchart showing the second switching control. [Figure 4] FIG. 4 is a flowchart showing braking control. [Figure 5] Figure 5(a) is a time chart showing changes in filter temperature. Figure 5(b) is a time chart showing changes in the normal regeneration mode setting. Figure 5(c) is a time chart showing changes in the strong regeneration mode setting. Figure 5(d) is a time chart showing changes in the vehicle's deceleration request status. DETAILED DESCRIPTION OF THE INVENTION

[0010] <Vehicle Overview> An embodiment of the present invention will now be described with reference to Figures 1 to 5. First, a schematic configuration of a vehicle 100 will be described.

[0011] 1, vehicle 100 includes a spark-ignition internal combustion engine 10. Vehicle 100 also includes a first motor generator 71 and a second motor generator 72 that function as both an electric motor and a generator. Therefore, vehicle 100 is a so-called hybrid vehicle.

[0012] The internal combustion engine 10 includes a plurality of cylinders 11, a crankshaft 12, an intake passage 21, a throttle valve 22, a plurality of fuel injection valves 23, a plurality of ignition devices 24, an exhaust passage 26, a three-way catalyst 27, and a filter 28.

[0013] Each cylinder 11 is a space for burning a mixture of fuel and intake air. The internal combustion engine 10 has four cylinders 11. A crankshaft 12 is connected to a piston (not shown) located in each cylinder 11. The crankshaft 12 rotates due to the combustion of the mixture of fuel and intake air in the cylinders 11.

[0014] The intake passage 21 is connected to the cylinders 11. A portion of the intake passage 21, including the downstream end, branches into four. Each of the branched passages is connected to one of the cylinders 11. The intake passage 21 introduces intake air from outside the internal combustion engine 10 into each of the cylinders 11. An intake valve (not shown) is located at the connection between the intake passage 21 and each of the cylinders 11. The intake valve opens and closes the connection between the intake passage 21 and each of the cylinders 11. The throttle valve 22 is located upstream of the branched portion of the intake passage 21. The throttle valve 22 adjusts the amount of intake air flowing through the intake passage 21.

[0015] The fuel injection valves 23 are located near the downstream end of the intake passage 21. The internal combustion engine 10 is equipped with four fuel injection valves 23 corresponding to the four cylinders 11. The fuel injection valves 23 inject fuel supplied from a fuel tank (not shown) into the intake passage 21. As a result, fuel from the fuel injection valves 23 is supplied to the cylinders 11. The ignition devices 24 are located in the cylinders 11. The internal combustion engine 10 is equipped with four ignition devices 24 corresponding to the four cylinders 11. The ignition devices 24 ignite an air-fuel mixture of fuel and intake air by spark discharge.

[0016] The exhaust passage 26 is connected to the cylinders 11. A portion of the exhaust passage 26, including the upstream end, branches into four. Each of the branched passages is connected to one of the cylinders 11. The exhaust passage 26 discharges exhaust gas from each of the cylinders 11 to the outside of the internal combustion engine 10. Note that exhaust valves (not shown) are located at the connection points between the exhaust passage 26 and each of the cylinders 11. The exhaust valves open and close the connection points between the exhaust passage 26 and each of the cylinders 11.

[0017] The three-way catalyst 27 is located downstream of the branched portion of the exhaust passage 26. The three-way catalyst 27 purifies the exhaust gas flowing through the exhaust passage 26. Specifically, the three-way catalyst 27 purifies hydrocarbons, carbon monoxide, and nitrogen oxides in the exhaust gas. In the present embodiment, the three-way catalyst 27 is an example of a catalyst. The filter 28 is located downstream of the three-way catalyst 27 in the exhaust passage 26. The filter 28 collects particulate matter contained in the exhaust gas flowing through the exhaust passage 26.

[0018] The vehicle 100 includes a first planetary gear mechanism 40 , a ring gear shaft 45 , a second planetary gear mechanism 50 , a reduction mechanism 62 , a differential mechanism 63 , and a plurality of drive wheels 64 . The first planetary gear mechanism 40 includes a sun gear 41, a ring gear 42, a plurality of pinion gears 43, and a carrier 44. The sun gear 41 is an external gear. The sun gear 41 is connected to the first motor generator 71. The ring gear 42 is an internal gear and is located coaxially with the sun gear 41. Each pinion gear 43 is located between the sun gear 41 and the ring gear 42. Each pinion gear 43 meshes with both the sun gear 41 and the ring gear 42. The carrier 44 supports the pinion gear 43. The pinion gear 43 is rotatable on its own axis and is capable of revolving by rotating together with the carrier 44. The carrier 44 is connected to the crankshaft 12.

[0019] The ring gear shaft 45 is connected to the ring gear 42. The ring gear shaft 45 is also connected to drive wheels 64 via a reduction mechanism 62 and a differential mechanism 63. The reduction mechanism 62 reduces the rotational speed of the ring gear shaft 45 and outputs it. The differential mechanism 63 allows a difference in rotational speed to occur between the left and right drive wheels 64.

[0020] The second planetary gear mechanism 50 includes a sun gear 51, a ring gear 52, a plurality of pinion gears 53, a carrier 54, and a case 55. The sun gear 51 is an external gear. The sun gear 51 is connected to the second motor generator 72. The ring gear 52 is an internal gear and is located coaxially with the sun gear 51. The ring gear 52 is connected to the ring gear shaft 45. Each pinion gear 53 is located between the sun gear 51 and the ring gear 52. Each pinion gear 53 meshes with both the sun gear 51 and the ring gear 52. The carrier 54 supports the pinion gear 53. The pinion gear 53 is rotatable. The carrier 54 is fixed to the case 55. Therefore, the pinion gear 53 is unable to revolve.

[0021] In this embodiment, the crankshaft 12 of the internal combustion engine 10 is connected to a plurality of drive wheels 64 via the first planetary gear mechanism 40, the ring gear shaft 45, the reduction mechanism 62, and the differential mechanism 63. Therefore, the crankshaft 12 of the internal combustion engine 10 is capable of transmitting power to the drive wheels 64. In addition, the rotating shaft of the second motor generator 72 is connected to the plurality of drive wheels 64 via the second planetary gear mechanism 50, the ring gear shaft 45, the reduction mechanism 62, and the differential mechanism 63. Therefore, the rotating shaft of the second motor generator 72 is capable of transmitting power to the drive wheels 64.

[0022] The vehicle 100 is equipped with a battery 75, a first inverter 76, and a second inverter 77. The battery 75 is a secondary battery. The first inverter 76 converts AC power to DC power between the first motor generator 71 and the battery 75. The first inverter 76 also adjusts the amount of power exchanged between the first motor generator 71 and the battery 75. The second inverter 77 converts AC power to DC power between the second motor generator 72 and the battery 75. The second inverter 77 adjusts the amount of power exchanged between the second motor generator 72 and the battery 75.

[0023] 1, the vehicle 100 is equipped with an air flow meter 81, a water temperature sensor 82, an intake air temperature sensor 83, a crank angle sensor 84, an accelerator operation amount sensor 85, and a vehicle speed sensor 86. The vehicle 100 also is equipped with a changeover switch 87 and a display 89.

[0024] The air flow meter 81 detects the intake air amount GA, which is the amount of intake air flowing per unit time through the intake passage 21. The water temperature sensor 82 detects the coolant temperature THW, which is the temperature of the coolant flowing through each part of the internal combustion engine 10. The intake air temperature sensor 83 detects the intake air temperature THA, which is the temperature of the intake air flowing through the intake passage 21.

[0025] The crank angle sensor 84 detects the crank angle SC, which is the rotational position of the crankshaft 12. The accelerator operation amount sensor 85 detects the accelerator operation amount ACC, which is the amount of operation of the accelerator pedal operated by the driver. The vehicle speed sensor 86 detects the vehicle speed SP, which is the speed of the vehicle 100.

[0026] The selector switch 87 is located near the driver's seat of the vehicle 100. The selector switch 87 is a switch that allows the driver of the vehicle 100 to switch between a normal regeneration mode and a strong regeneration mode. Here, the normal regeneration mode is a mode in which, when deceleration of the vehicle 100 is required, the second motor generator 72 is operated as a generator to generate a braking force for the vehicle 100. On the other hand, the strong regeneration mode is a mode in which, when deceleration of the vehicle 100 is required, the second motor generator 72 is operated as a generator to generate a braking force for the vehicle 100 that is greater than that in the normal regeneration mode. The selector switch 87 is sometimes referred to as a regeneration boost switch, etc. The display 89 is located near the driver's seat of the vehicle 100. The display 89 is capable of displaying various information.

[0027] The vehicle 100 is equipped with a control device 90. The control device 90 acquires various information from an air flow meter 81, a water temperature sensor 82, an intake air temperature sensor 83, a crank angle sensor 84, an accelerator operation amount sensor 85, a vehicle speed sensor 86, and a changeover switch 87.

[0028] The control device 90 includes an execution device 91 and a storage device 92. An example of the execution device 91 is a CPU. The storage device 92 includes a read-only ROM, a readable / writable volatile RAM, and a readable / writable non-volatile storage. The storage device 92 stores various programs and various data in advance. Specifically, the storage device 92 stores a control program 92A in advance as one of the various programs. The execution device 91 executes the control program 92A stored in the storage device 92 to perform various processes described below. In other words, the execution device 91 realizes various processes related to the control method of the vehicle 100 by executing the control program 92A stored in the storage device 92.

[0029] An execution unit 91 of the control device 90 calculates a vehicle required driving force, which is a required value of driving force necessary for the vehicle 100 to travel, based on the accelerator operation amount ACC and the vehicle speed SP. The execution unit 91 determines a torque distribution among the internal combustion engine 10, the first motor generator 71, and the second motor generator 72 based on the vehicle required driving force. The execution unit 91 controls the output of the internal combustion engine 10 and the power running and regeneration of the first motor generator 71 and the second motor generator 72 based on the torque distribution among the internal combustion engine 10, the first motor generator 71, and the second motor generator 72. Specifically, the execution unit 91 outputs a control signal to the internal combustion engine 10 to control the opening of the throttle valve 22, the fuel injection amount from the fuel injection valve 23, the ignition timing of the ignition device 24, etc. The execution unit 91 also outputs a control signal to the first inverter 76 to control the first motor generator 71 via the first inverter 76. Furthermore, the execution device 91 controls the second motor generator 72 via the second inverter 77 by outputting a control signal to the second inverter 77 .

[0030] Furthermore, when the vehicle 100 is traveling, the execution device 91 of the control device 90 selects either the EV mode or the HV mode as the traveling mode of the vehicle 100. Here, the EV mode is a traveling mode in which the internal combustion engine 10 is stopped and one or more motor generators selected from the first motor generator 71 and the second motor generator 72 are driven to travel the vehicle 100. Therefore, in the EV mode, the vehicle 100 is traveled by the driving force of the first motor generator 71 and the driving force of the second motor generator 72. Furthermore, the HV mode is a traveling mode of the vehicle 100 in which the internal combustion engine 10 is driven in addition to the driving force of the first motor generator 71 and the second motor generator 72 to travel the vehicle 100. Therefore, in the HV mode, the vehicle 100 is traveled by the driving force of the internal combustion engine 10 in addition to the driving force of the first motor generator 71 and the second motor generator 72.

[0031] The execution unit 91 of the control device 90 selects the EV mode, for example, when the charging rate of the battery 75 has a sufficient margin and the above-mentioned required vehicle driving force is small. Examples of when the required vehicle driving force is small include when the vehicle 100 starts moving and when the vehicle 100 is running under a light load with low acceleration. On the other hand, the execution unit 91 selects the HV mode, for example, when the charging rate of the battery 75 does not have a sufficient margin.

[0032] The execution unit 91 of the control device 90 calculates the engine speed NE, which is the number of revolutions per unit time of the crankshaft 12, based on the crank angle SC. The execution unit 91 calculates the engine load factor KL based on the engine speed NE and the intake air amount GA. Here, the engine load factor KL represents the ratio of the current cylinder inflow air amount to the cylinder inflow air amount when the internal combustion engine 10 is operated steadily at the current engine speed NE with the throttle valve 22 fully open. The cylinder inflow air amount is the amount of intake air flowing into each cylinder 11 during the intake stroke.

[0033] The execution unit 91 of the control device 90 calculates the catalyst temperature TSC, which is the temperature of the three-way catalyst 27, based on the operating conditions of the internal combustion engine 10, such as the intake air charging efficiency and the engine rotation speed NE. The intake air charging efficiency is a value obtained by dividing the mass of intake air actually introduced into the cylinder 11 from the intake passage 21 by the mass of intake air that can be introduced into the cylinder 11 under standard atmospheric conditions. The execution unit 91 also calculates the filter temperature TF, which is the temperature of the filter 28, based on the operating conditions of the internal combustion engine 10, such as the intake air charging efficiency and the engine rotation speed NE. The execution unit 91 calculates the amount of particulate matter deposited on the filter 28 per unit time based on the engine rotation speed NE, the engine load factor KL, and the filter temperature TF. The execution unit 91 then calculates the PM deposition amount PS, which is the deposition amount of particulate matter on the filter 28, by integrating the amount of particulate matter deposited on the filter 28 per unit time.

[0034] <First switching control> Next, the first switching control executed by the control device 90 will be described with reference to Fig. 2. This first switching control is one of the controls for switching between the normal regeneration mode and the strong regeneration mode. In this embodiment, the execution device 91 of the control device 90 starts the first switching control at every predetermined control cycle, with the necessary condition being that the control device 90 is operating.

[0035] As shown in FIG. 2, when the execution device 91 of the control device 90 starts the first switching control, it executes the processing of step S11. In step S11, the execution device 91 determines whether or not the driver of the vehicle 100 has requested the normal regeneration mode. Specifically, when the selector switch 87 is pressed while the strong regeneration mode is set, the execution device 91 determines that the driver of the vehicle 100 has requested the normal regeneration mode. In step S11, if the execution device 91 determines that the driver of the vehicle 100 has not requested the normal regeneration mode (S11: NO), the execution device 91 terminates the current first switching control. On the other hand, in step S11, if the execution device 91 determines that the driver of the vehicle 100 has requested the normal regeneration mode (S11: YES), the execution device 91 proceeds to step S21. In other words, the execution device 91 proceeds to step S21 based on the request of the driver of the vehicle 100.

[0036] In step S21, the execution device 91 sets the normal regeneration mode as the regeneration mode. The execution device 91 also outputs a control signal to the display 89 to notify the driver of the vehicle 100 on the display 89 that the normal regeneration mode has been set. For example, the execution device 91 displays a message such as "Normal regeneration mode has been set" on the display 89. In this embodiment, the processing of step S21 is processing to selectively set one of the normal regeneration mode and the strong regeneration mode. After step S21, the execution device 91 ends the current first switching control.

[0037] <Second switching control> Next, the second switching control executed by the control device 90 will be described with reference to Fig. 3. This second switching control is one of the controls for switching between the normal regeneration mode and the strong regeneration mode. In this embodiment, the execution device 91 of the control device 90 starts the second switching control at every predetermined control cycle, with the necessary condition being that the control device 90 is operating.

[0038] 3, when the executing unit 91 of the control device 90 starts the second switching control, it executes the processing of step S41. In step S41, the executing unit 91 determines whether the filter temperature TF is lower than a predetermined specified temperature A. Here, the specified temperature A is, for example, a temperature that is lower by a certain value than the upper limit temperature allowed for the filter 28 in terms of design. An example of the specified temperature A is several hundred degrees Celsius. In step S41, if the executing unit 91 determines that the filter temperature TF is lower than the specified temperature A (S41: YES), the executing unit 91 proceeds to the processing of step S42.

[0039] In step S42, the execution device 91 determines whether the strong regeneration mode has been requested by the driver of the vehicle 100. Specifically, when the selector switch 87 is pressed while the normal regeneration mode is set, the execution device 91 determines that the strong regeneration mode has been requested by the driver of the vehicle 100. If the execution device 91 determines in step S42 that the strong regeneration mode has not been requested by the driver of the vehicle 100 (S42: NO), the execution device 91 terminates the current second switching control. On the other hand, if the execution device 91 determines in step S42 that the strong regeneration mode has been requested by the driver of the vehicle 100 (S42: YES), the execution device 91 proceeds to step S51. In other words, the execution device 91 proceeds to step S51 based on the request of the driver of the vehicle 100.

[0040] In step S51, the execution device 91 sets the strong regeneration mode as the regeneration mode. The execution device 91 also outputs a control signal to the display 89 to notify the driver of the vehicle 100 on the display 89 that the strong regeneration mode has been set. For example, the execution device 91 displays a message such as "Strong regeneration mode has been set" on the display 89. In this embodiment, the processing of step S51 is processing to selectively set one of the normal regeneration mode and the strong regeneration mode. After step S51, the execution device 91 ends the current second switching control.

[0041] On the other hand, in the above-mentioned step S41, if the execution device 91 determines that the filter temperature TF is equal to or higher than the specified temperature A (S41: NO), the execution device 91 proceeds to step S52. In other words, if the filter temperature TF is equal to or higher than the specified temperature A, the execution device 91 proceeds to step S52 regardless of the request of the driver of the vehicle 100.

[0042] In step S52, the execution device 91 sets the normal regeneration mode as the regeneration mode. Furthermore, when the setting is changed from the strong regeneration mode to the normal regeneration mode because the filter temperature TF is equal to or higher than the specified temperature A, the execution device 91 outputs a control signal to the display 89 to notify the driver of the vehicle 100 on the display 89 that the normal regeneration mode has been set. For example, the execution device 91 displays a message on the display 89 such as, "The normal regeneration mode has been set due to the high filter temperature." In this embodiment, the processing of step S52 is processing to set the normal regeneration mode from the normal regeneration mode and the strong regeneration mode. Furthermore, the processing of steps S21, S51, and S52 is an example of a setting processing. After step S52, the execution device 91 ends the second switching control.

[0043] <Braking control> Next, the braking control executed by the control device 90 will be described with reference to Fig. 4. This braking control is a control for generating a braking force on the vehicle 100. In this embodiment, the execution device 91 of the control device 90 starts the braking control at every predetermined control cycle, with the necessary conditions being that the control device 90 is operating and that the vehicle speed SP is higher than a predetermined specified speed. An example of the specified speed is about zero kilometers per hour to a dozen kilometers per hour.

[0044] As shown in FIG. 4, when the execution device 91 of the control device 90 starts braking control, it executes the processing of step S71. In step S71, the execution device 91 determines whether deceleration is required for the vehicle 100. Specifically, the execution device 91 determines that deceleration is required for the vehicle 100 when the accelerator operation amount ACC is zero. In this embodiment, the accelerator operation amount ACC becomes zero when the driver of the vehicle 100 is not depressing the accelerator pedal. In step S71, if the execution device 91 determines that deceleration is not required for the vehicle 100 (S71: NO), the execution device 91 ends the current braking control. On the other hand, in step S71, if the execution device 91 determines that deceleration is required for the vehicle 100 (S71: YES), the execution device 91 proceeds to the processing of step S72.

[0045] In step S72, the execution unit 91 determines whether the filter temperature TF is less than a predetermined specified temperature A. In this embodiment, the specified temperature A in step S72 is the same value as the specified temperature A in step S41. If the execution unit 91 determines in step S72 that the filter temperature TF is less than the specified temperature A (S72: YES), the execution unit 91 proceeds to step S81. In other words, the execution unit 91 proceeds to step S81 on the condition that deceleration is required in the vehicle 100 and that the filter temperature TF is less than the specified temperature A.

[0046] In step S81, the execution device 91 executes a first braking process. In the first braking process, the execution device 91 outputs a control signal to the internal combustion engine 10 to generate a braking force on the vehicle 100 by engine braking using the internal combustion engine 10. Specifically, the execution device 91 closes the throttle valve 22. The execution device 91 also stops the supply of fuel from the fuel injection valve 23 to the cylinder 11 and stops fuel combustion in the cylinder 11. Furthermore, in the first braking process, the execution device 91 outputs a control signal to the second inverter 77 to operate the second motor generator 72 as a generator, thereby generating a braking force on the vehicle 100. At this time, the execution device 91 generates a braking force on the vehicle 100 in one of the normal regeneration mode and the strong regeneration mode set in the first switching control and the second switching control. In this embodiment, the first braking process corresponds to the combustion stop process and the regeneration process. After step S81, the execution device 91 ends the current braking control.

[0047] On the other hand, if the execution device 91 determines in step S72 that the filter temperature TF is equal to or higher than the specified temperature A (S72: NO), the execution device 91 proceeds to step S82. In other words, if deceleration is required in the vehicle 100 and the filter temperature TF is equal to or higher than the specified temperature A, the execution device 91 proceeds to step S82.

[0048] In step S82, the execution unit 91 executes a second braking process. In the second braking process, the execution unit 91 outputs a control signal to the internal combustion engine 10 to combust fuel in the cylinders 11 of the internal combustion engine 10. Specifically, the execution unit 91 closes the throttle valve 22. Note that even when the throttle valve 22 is closed, a small amount of intake air may flow from the intake passage 21 to the cylinders 11. The execution unit 91 also combusts fuel in the cylinders 11 while supplying fuel from the fuel injection valves 23 to the cylinders 11. At this time, the execution unit 91 controls the internal combustion engine 10 so that the combustion torque is equal to the maintenance torque. Here, the combustion torque is the torque of the crankshaft 12 generated by the combustion of fuel in the cylinders 11. The maintenance torque is the minimum torque of the crankshaft 12 that allows the internal combustion engine 10 to continue operating autonomously. Furthermore, in the second braking process, the execution device 91 outputs a control signal to the second inverter 77 to operate the second motor generator 72 as a generator, thereby generating a braking force for the vehicle 100. At this time, the execution device 91 generates a braking force for the vehicle 100 in the normal regeneration mode set by the first switching control and the second switching control. Here, the braking force by the internal combustion engine 10 obtained in the second braking process of step S82 is smaller than the braking force by the internal combustion engine 10 obtained in the first braking process of step S81. Therefore, the execution device 91 increases the braking force by the second motor generator 72 to compensate for the braking force by the internal combustion engine 10. In this embodiment, the second braking process corresponds to the combustion continuation process and the regeneration process. After step S82, the execution device 91 ends the current braking control.

[0049] <Operation of this embodiment> For example, as shown in Fig. 5(c), it is assumed that at time t1, the strong regeneration mode is set in response to the operation of the selector switch 87 by the driver of the vehicle 100. Furthermore, for example, as shown in Fig. 5(a), it is assumed that after time t1, while the vehicle 100 is running, the filter temperature TF increases and decreases due to the combustion of fuel in the cylinders 11 of the internal combustion engine 10.

[0050] Then, for example, as shown in Fig. 5(d), assume that deceleration of the vehicle 100 is requested at time t3 after time t1. If, at this time t3, the filter temperature TF is lower than the specified temperature A, for example, as shown by the two-dot chain line in Fig. 5(a), the execution device 91 executes the first braking process in step S81, as shown in Fig. 4. That is, the execution device 91 executes a combustion stop process that generates a braking force for the vehicle 100 by engine braking using the internal combustion engine 10, and also executes a regeneration process that generates a braking force for the vehicle 100 by operating the second motor-generator 72 as a generator.

[0051] On the other hand, at time t3, if the filter temperature TF is equal to or higher than the specified temperature A, as shown by the solid line in FIG. 5A, for example, the execution device 91 executes the second braking process in step S82 as shown in FIG. 4. That is, the execution device 91 executes a combustion continuation process in which fuel is supplied from the fuel injection valve 23 to the cylinder 11 and burned in the cylinder 11, and also executes a regeneration process in which the second motor-generator 72 operates as a generator to generate a braking force for the vehicle 100. In the combustion continuation process, the braking force by the internal combustion engine 10 is smaller than in the combustion stop process. Therefore, in the regeneration process in step S82, it is necessary to increase the braking force by the second motor-generator 72 to compensate for the braking force by the internal combustion engine 10. Here, the second motor-generator 72 has an upper limit on the braking force that is determined by the structure of the second motor-generator 72, the limit on the power that can be input to the battery 75, and the like. Furthermore, in the strong regeneration mode, the braking force by the second motor-generator 72 is greater than in the normal regeneration mode, and therefore, due to the existence of the upper limit, there is a possibility that there is no room for the braking force by the second motor-generator 72 to increase. Therefore, if the strong regeneration mode is continuously set as shown by the two-dot chain line in FIG. 5(c), when the braking force by the internal combustion engine 10 decreases in response to a change in the filter temperature TF, it may not be possible to increase the braking force by the second motor-generator 72 to compensate for the braking force by the internal combustion engine 10. As a result, the sum of the braking forces by the internal combustion engine 10 and the second motor-generator 72 may be reduced. In other words, the braking force of the vehicle 100 in the strong regeneration mode that the driver of the vehicle 100 expects may or may not be achieved due to a change in the filter temperature TF.

[0052] <Effects of this embodiment> (1) According to this embodiment, for example, as shown by the solid line in FIG. 5A, when the filter temperature TF becomes equal to or higher than the specified temperature A at time t2, which is after time t1 but before time t3, the execution device 91 sets the normal regeneration mode as shown in FIG. 5B. In this normal regeneration mode, the braking amount by the second motor-generator 72 is smaller than in the strong regeneration mode, so there is room for the braking force by the second motor-generator 72 to be increased. Therefore, even if the braking force by the internal combustion engine 10 is reduced at time t3 because the filter temperature TF is equal to or higher than the specified temperature A, the braking force by the second motor-generator 72 can be increased to compensate for the braking force by the internal combustion engine 10. Therefore, for example, a change in the sum of the braking forces by the internal combustion engine 10 and the second motor-generator 72 is suppressed every time the filter temperature TF changes. As a result, while enabling regeneration processing in the strong regeneration mode, it is possible to suppress a situation in which the braking force of the vehicle 100 changes every time the filter temperature TF changes, due to the strong regeneration mode being set.

[0053] As described above, if the filter temperature TF is equal to or higher than the specified temperature A at time t3, as shown by the solid line in FIG. 5A, for example, the execution device 91 executes the second braking process in step S82 as shown in FIG. 4. That is, the execution device 91 executes a combustion continuation process in which fuel is supplied from the fuel injection valve 23 to the cylinder 11 and the fuel is burned in the cylinder 11, and also executes a regeneration process in which the second motor-generator 72 operates as a generator to generate a braking force for the vehicle 100. In this combustion continuation process, oxygen contained in the air is consumed by the combustion of fuel in the cylinder 11. Therefore, the amount of oxygen flowing from the cylinder 11 to the exhaust passage 26 decreases. As a result, the combustion of particulate matter in the filter 28 is suppressed, and the increase in the filter temperature TF due to the combustion can be suppressed.

[0054] (2) In the combustion continuation process in step S82, the execution device 91 controls the internal combustion engine 10 so that the combustion torque is equal to the maintenance torque. This prevents the braking force of the second motor-generator 72 from becoming excessively large in order to compensate for the braking force of the internal combustion engine 10, compared to when the combustion torque is greater than the maintenance torque.

[0055] (3) As shown in Fig. 3, if the execution device 91 determines in step S41 that the filter temperature TF is equal to or higher than the specified temperature A, then in step S52, the execution device 91 sets the normal regeneration mode as the regeneration mode. Then, if the setting is changed from the strong regeneration mode to the normal regeneration mode because the filter temperature TF is equal to or higher than the specified temperature A regardless of the request of the driver of the vehicle 100, the execution device 91 notifies the driver of the vehicle 100 on the display 89 that the normal regeneration mode has been set. In this way, even if the setting is changed from the strong regeneration mode to the normal regeneration mode because the filter temperature TF is equal to or higher than the specified temperature A regardless of the request of the driver of the vehicle 100, the driver of the vehicle 100 can be prevented from feeling uncomfortable by being notified of this.

[0056] <Example of change> This embodiment can be modified as follows: This embodiment and the following modifications can be combined and implemented within the scope of technical compatibility.

[0057] In the above embodiment, the first switching control may be changed. For example, in step S21, the manner in which the driver of vehicle 100 is notified may be changed. As a specific example, execution device 91 may output a control signal to a speaker provided in vehicle 100, thereby notifying the driver of vehicle 100 that the normal regeneration mode has been set by a sound output from the speaker.

[0058] For example, in step S21, the notification to the driver of vehicle 100 may be omitted. Specifically, if the normal regeneration mode is requested by the driver of vehicle 100, the execution device 91 sets the normal regeneration mode in step S21. Therefore, even if the notification to the driver of vehicle 100 is omitted, the impact is small.

[0059] In the above embodiment, the second switching control may be changed. For example, in step S51, the manner in which the driver of vehicle 100 is notified may be changed. As a specific example, execution device 91 may output a control signal to a speaker provided in vehicle 100, thereby notifying the driver of vehicle 100 that the strong regeneration mode has been set by a sound output from the speaker.

[0060] For example, in step S51, the notification to the driver of vehicle 100 may be omitted. Specifically, if the strong regeneration mode is requested by the driver of vehicle 100, the execution device 91 sets the strong regeneration mode in step S51. Therefore, even if the notification to the driver of vehicle 100 is omitted, the impact is small.

[0061] For example, in step S52, the manner in which the driver of the vehicle 100 is notified may be changed. As a specific example, the execution device 91 may output a control signal to a speaker provided in the vehicle 100, thereby notifying the driver of the vehicle 100 that the normal regeneration mode has been set by a sound output from the speaker.

[0062] For example, in step S52, the notification to the driver of the vehicle 100 may be omitted. Specifically, from the viewpoint that the execution device 91 sets the normal regeneration mode in step S52 when the filter temperature TF is equal to or higher than the specified temperature A, the notification to the driver of the vehicle 100 may be omitted.

[0063] In the above embodiment, the braking control may be changed. For example, in step S81, the first braking process may be changed. As a specific example, in the first braking process in step S81, the combustion stop process that generates a braking force on the vehicle 100 by engine braking using the internal combustion engine 10 may be omitted. As an example, even if deceleration is required in the vehicle 100 and the filter temperature TF is lower than the specified temperature A, if the deceleration required in the vehicle 100 is small, the execution device 91 may execute only the regeneration process in step S81. In this case, the execution device 91 may stop engine braking using the internal combustion engine 10, for example, by opening the throttle valve 22.

[0064] For example, in step S82, the second braking process may be changed. As a specific example, in the combustion continuation process in step S82, the execution device 91 may control the internal combustion engine 10 so that the combustion torque is smaller than the maintained torque. Note that, from the viewpoint of reducing the braking force by the second motor-generator 72 to supplement the braking force by the internal combustion engine 10, it is preferable to control the internal combustion engine 10 so that the combustion torque is smaller than the maintained torque. Also, as a specific example, in the combustion continuation process in step S82, the execution device 91 may control the internal combustion engine 10 so that the combustion torque is larger than the maintained torque.

[0065] In the above embodiment, the configuration of the vehicle 100 may be changed. For example, the power transmission configuration from the crankshaft 12 of the internal combustion engine 10 to the drive wheels 64 may be changed. In other words, the present technology can be applied to any vehicle 100 in which the crankshaft 12 of the internal combustion engine 10 can transmit power to the drive wheels 64.

[0066] For example, the configuration for transmitting power from the rotation shaft of the second motor generator 72 to the drive wheels 64 may be changed. In other words, the present technology may be applied to any vehicle 100 in which the rotation shaft of the motor generator is capable of transmitting power to the drive wheels 64.

[0067] For example, the configuration of the control device 90 may be changed. Specifically, the control device 90 may be configured as a circuit including one or more processors that execute various processes according to a computer program (software). The control device 90 may also be configured as a circuit including one or more dedicated hardware circuits, such as an application-specific integrated circuit (ASIC), that execute at least some of the various processes, or a combination thereof. The processor includes a CPU and memory such as RAM and ROM. The memory stores program code or instructions configured to cause the CPU to execute processes. The memory, i.e., computer-readable medium, includes any medium accessible by a general-purpose or dedicated computer. [Explanation of symbols]

[0068] 10...internal combustion engine 11...cylinder 12...crankshaft 21...intake passage 22...throttle valve 23...fuel injection valve 24...ignition device 26...exhaust passage 27...three-way catalyst 28...filter 40...first planetary gear mechanism 45...ring gear shaft 50...second planetary gear mechanism 62...reduction mechanism 63...differential mechanism 64...drive wheels 71...first motor generator 72...second motor generator 75...battery 76...first inverter 77...second inverter 81...air flow meter 82...water temperature sensor 83...intake air temperature sensor 84...crank angle sensor 85...accelerator operation amount sensor 86...vehicle speed sensor 87...selector switch 89...display 90...control device 91...execution device 92...storage device 92A...control program 100...vehicle

Claims

1. an internal combustion engine having cylinders which are spaces for burning fuel, fuel injection valves for supplying fuel into the cylinders, an exhaust passage connected to the cylinders, a catalyst located in the exhaust passage for purifying exhaust gas, a filter located in the exhaust passage downstream of the catalyst for collecting particulate matter contained in the exhaust gas, and a crankshaft which rotates based on the combustion of fuel in the cylinders and is capable of transmitting power to drive wheels; a motor generator capable of transmitting power to the drive wheels; A control device applied to a vehicle equipped with a combustion stop process that generates a braking force on the vehicle by an engine brake using the internal combustion engine while stopping the supply of fuel from the fuel injection valve to the cylinder, when deceleration of the vehicle is required and the filter temperature is lower than a predetermined specified temperature; a combustion continuation process for supplying fuel from the fuel injection valve to the cylinder and burning the fuel in the cylinder when deceleration is required in the vehicle and the filter temperature is equal to or higher than the specified temperature; a setting process for selectively setting one of a normal regeneration mode in which the motor generator is operated as a generator to generate the braking force and a strong regeneration mode in which the motor generator is operated as a generator to generate a braking force greater than that in the normal regeneration mode, based on a request from a driver of the vehicle; a regeneration process for generating the braking force in one of the normal regeneration mode and the strong regeneration mode set in the setting process when deceleration is required in the vehicle; is executable, In the setting process, when the filter temperature is equal to or higher than the specified temperature, the normal regeneration mode is set between the normal regeneration mode and the strong regeneration mode regardless of a request from the driver of the vehicle. Vehicle control device.

2. When the torque of the crankshaft generated by the combustion of fuel in the cylinder is defined as a combustion torque, and the minimum torque of the crankshaft that allows the internal combustion engine to continue operating independently is defined as a maintenance torque, In the combustion continuation process, the internal combustion engine is controlled so that the combustion torque is equal to or less than the maintenance torque. The vehicle control device according to claim 1 .

3. In the setting process, when the filter temperature is equal to or higher than the specified temperature and the setting is changed from the strong regeneration mode to the normal regeneration mode regardless of a request from the driver of the vehicle, the driver of the vehicle is notified that the normal regeneration mode has been set. The vehicle control device according to claim 1 or 2.

4. an internal combustion engine having cylinders which are spaces for burning fuel, fuel injection valves for supplying fuel into the cylinders, an exhaust passage connected to the cylinders, a catalyst located in the exhaust passage for purifying exhaust gas, a filter located in the exhaust passage downstream of the catalyst for collecting particulate matter contained in the exhaust gas, and a crankshaft which rotates based on the combustion of fuel in the cylinders and is capable of transmitting power to drive wheels; a motor generator capable of transmitting power to the drive wheels; The present invention is applied to a control device for a vehicle equipped with The control device a combustion stop process that generates a braking force on the vehicle by an engine brake using the internal combustion engine while stopping the supply of fuel from the fuel injection valve to the cylinder, when deceleration of the vehicle is required and the filter temperature is lower than a predetermined specified temperature; a combustion continuation process for supplying fuel from the fuel injection valve to the cylinder and burning the fuel in the cylinder when deceleration is required in the vehicle and the filter temperature is equal to or higher than the specified temperature; a setting process for selectively setting one of a normal regeneration mode in which the motor generator is operated as a generator to generate the braking force and a strong regeneration mode in which the motor generator is operated as a generator to generate a braking force greater than that in the normal regeneration mode, based on a request from a driver of the vehicle; a regeneration process for generating the braking force in one of the normal regeneration mode and the strong regeneration mode set in the setting process when deceleration is required in the vehicle; Make it executable, In the setting process, when the filter temperature is equal to or higher than the specified temperature, the normal regeneration mode is set between the normal regeneration mode and the strong regeneration mode regardless of a request from the driver of the vehicle. Vehicle control program.

5. an internal combustion engine having cylinders which are spaces for burning fuel, fuel injection valves for supplying fuel into the cylinders, an exhaust passage connected to the cylinders, a catalyst located in the exhaust passage for purifying exhaust gas, a filter located in the exhaust passage downstream of the catalyst for collecting particulate matter contained in the exhaust gas, and a crankshaft which rotates based on the combustion of fuel in the cylinders and is capable of transmitting power to drive wheels; a motor generator capable of transmitting power to the drive wheels; The present invention is applied to a control device for a vehicle equipped with The control device a combustion stop process that generates a braking force on the vehicle by an engine brake using the internal combustion engine while stopping the supply of fuel from the fuel injection valve to the cylinder, when deceleration of the vehicle is required and the filter temperature is lower than a predetermined specified temperature; a combustion continuation process for supplying fuel from the fuel injection valve to the cylinder and burning the fuel in the cylinder when deceleration is required in the vehicle and the filter temperature is equal to or higher than the specified temperature; a setting process for selectively setting one of a normal regeneration mode in which the motor generator is operated as a generator to generate the braking force and a strong regeneration mode in which the motor generator is operated as a generator to generate a braking force greater than that in the normal regeneration mode, based on a request from a driver of the vehicle; a regeneration process for generating the braking force in one of the normal regeneration mode and the strong regeneration mode set in the setting process when deceleration is required in the vehicle; is executable, In the setting process, when the filter temperature is equal to or higher than the specified temperature, the normal regeneration mode is set between the normal regeneration mode and the strong regeneration mode regardless of a request from the driver of the vehicle. How to control the vehicle.

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