Control device and control method for a vehicle

Abstract

A control device and a control method of a vehicle. A CPU executes filter regeneration processing, ignition processing, and stop processing. In the stop processing, the rotation of a crankshaft of an internal combustion engine is stopped as a condition during a deceleration period after the end of the ignition processing.

Description

Technical Field

[0001] This disclosure relates to vehicle control devices and control methods. Background Technology

[0002] Japanese Patent Application Publication No. 2018-065448 discloses a vehicle comprising an internal combustion engine, an electric generator, and a battery. The internal combustion engine has an exhaust passage for exhaust gas flow and a filter for capturing particulate matter contained in the exhaust gas. A control device, controlling the vehicle, coordinates the internal combustion engine and the electric generator to drive the vehicle. While driving the internal combustion engine and the electric generator, the control device performs a filter regeneration process, regenerating the filter when the amount of particulate matter (PM) collected by the filter reaches a predetermined amount. Furthermore, the control device terminates the filter regeneration process when the filter temperature reaches a predetermined temperature threshold. After terminating the filter regeneration process, the control device performs an ignition process, injecting fuel from the fuel injection valve and igniting it through the spark plug.

[0003] In the vehicle described in Japanese Patent Application Publication No. 2018-065448, the crankshaft of the internal combustion engine rotates regardless of whether either filter regeneration or ignition treatment is being performed. During crankshaft rotation, the intake and exhaust valves of the internal combustion engine open and close, thus the engine performs intake and exhaust. Therefore, the sounds and vibrations accompanying this intake and exhaust may be noticeable to the vehicle occupants. Summary of the Invention

[0004] To address the aforementioned issues, according to a first aspect of this disclosure, a vehicle control device is provided. The vehicle includes: an internal combustion engine having a cylinder, a fuel injection valve for injecting fuel into the cylinder, a spark plug for ignition within the cylinder, an exhaust passage for supplying exhaust gas from the cylinder, and a filter for capturing particulate matter contained in the exhaust gas; an electric generator connected to the crankshaft of the internal combustion engine; and a battery supplied with power from the electric generator. The control device is configured to perform a buildup calculation process, a filter regeneration process, an ignition process, and a stop process. The buildup calculation process calculates the amount of particulate matter (PM) collected by the filter. The filter regeneration process, under the condition that the PM buildup is above a predetermined amount and the vehicle is in a deceleration period, stops the fuel injection from the fuel injection valve while the crankshaft of the internal combustion engine is rotating, thereby causing the particulate matter collected by the filter to burn. The ignition process, under the condition that the filter temperature is above a predetermined temperature threshold and the vehicle is in a deceleration period, ends the filter regeneration process and injects fuel from the fuel injection valve for ignition through the spark plug. The stop process, under the condition that the vehicle is in a deceleration period after the ignition process has ended, stops the rotation of the crankshaft of the internal combustion engine.

[0005] To address the aforementioned issues, according to a second aspect of this disclosure, a vehicle control method is provided. The vehicle comprises: an internal combustion engine having a cylinder, a fuel injection valve for injecting fuel into the cylinder, a spark plug for ignition within the cylinder, an exhaust passage for supplying exhaust gas from the cylinder, and a filter for capturing particulate matter contained in the exhaust gas; an electric generator connected to the crankshaft of the internal combustion engine; and a battery supplied with power from the electric generator. The control method includes: a buildup calculation process, which calculates the buildup amount of particulate matter (PM) captured by the filter; a filter regeneration process, which, under the condition that the PM buildup amount is above a predetermined buildup amount and the vehicle is in a deceleration period, stops fuel injection from the fuel injection valve while the crankshaft of the internal combustion engine is rotating, thereby causing the particulate matter captured by the filter to burn; an ignition process, which, under the condition that the filter temperature is above a predetermined temperature threshold and the vehicle is in a deceleration period, ends the filter regeneration process and injects fuel from the fuel injection valve and ignites it through the spark plug; and a stop process, which, under the condition that the vehicle is in a deceleration period after the ignition process ends, stops the rotation of the crankshaft of the internal combustion engine. Attached Figure Description

[0006] Figure 1 This is a schematic diagram of the vehicle configuration according to one embodiment.

[0007] Figure 2 This is a flowchart illustrating a series of processes for controlling regeneration in one embodiment.

[0008] Figure 3 It is a timing diagram of a vehicle decelerating from a state of traveling at a certain speed. Figure 3 (a) is a time sequence diagram regarding vehicle speed. Figure 3 (b) is a timing diagram of the regeneration process. Figure 3 (c) is a time-series diagram of the filter temperature. Figure 3 (d) is the timing diagram of the internal combustion engine output. Figure 3 (e) is a time series diagram of the target value of the energy storage rate. Figure 3 (f) is a timing diagram of the upper limit of the battery input. Figure 3 (g) is a time series diagram of PM accumulation. Detailed Implementation

[0009] (One implementation method)

[0010] Hereinafter, an embodiment of the vehicle control device will be described with reference to the accompanying drawings. In this embodiment, the vehicle control device is mounted on the vehicle.

[0011] <General Components of a Vehicle>

[0012] First, the general configuration of the vehicle 100, which is controlled by the vehicle's control device, will be explained.

[0013] like Figure 1 As shown, vehicle 100 is equipped with a spark-ignition internal combustion engine 10. In addition, vehicle 100 is equipped with a first electric generator 71 and a second electric generator 72, which function as both an electric motor and a generator. Therefore, vehicle 100 is a so-called hybrid vehicle.

[0014] The internal combustion engine 10 includes multiple cylinders 11, a crankshaft 12, an intake passage 21, and a throttle valve 22. In addition, the internal combustion engine 10 includes multiple fuel injection valves 23, multiple spark plugs 24, an exhaust passage 26, a catalyst 27, and a filter 28.

[0015] Cylinder 11 is a space for burning the fuel-air mixture. The internal combustion engine 10 has four cylinders 11. An intake passage 21 is connected to each cylinder 11. A portion of the intake passage 21, including its downstream end, branches into four branches. Each branch is connected to a specific cylinder 11. The intake passage 21 introduces intake air from outside the internal combustion engine 10 into each cylinder 11. A throttle valve 22 is located in the intake passage 21, viewed from the branched portion as the upstream side. The throttle valve 22 adjusts the amount of intake air flowing through the intake passage 21.

[0016] Fuel injection valve 23 is located near the downstream end of intake passage 21. The internal combustion engine 10 has four fuel injection valves 23 corresponding to its four cylinders 11. The fuel injection valves 23 inject fuel supplied from a fuel tank (not shown) into the intake passage 21. That is, the fuel injection valves 23 supply fuel to the cylinders 11 via the intake passage 21. Spark plugs 24 are located in the cylinders 11. The internal combustion engine 10 has four spark plugs 24 corresponding to its four cylinders 11. The spark plugs 24 ignite the fuel-air mixture through spark discharge.

[0017] Exhaust passage 26 is connected to cylinder 11. A portion of exhaust passage 26, including the upstream end, branches into four branches. Each branch is connected to a cylinder 11. Exhaust passage 26 discharges exhaust gas from each cylinder 11 to the outside of the internal combustion engine 10.

[0018] Catalyst 27 is located in the exhaust passage 26, viewed from the branch portion as downstream. Catalyst 27 purifies the exhaust gas flowing in the exhaust passage 26. Filter 28 is located in the exhaust passage 26, viewed from the downstream side of catalyst 27. Filter 28 traps particulate matter contained in the exhaust gas flowing in the exhaust passage 26.

[0019] The crankshaft 12 is connected to pistons (not shown) located in each cylinder 11. When fuel burns in each cylinder 11, the piston in that cylinder 11 moves. As a result, the crankshaft 12 connected to the piston rotates.

[0020] 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 multiple drive wheels 64.

[0021] The first planetary gear mechanism 40 includes a sun gear 41, a ring gear 42, multiple pinions 43, and a gear carrier 44. The sun gear 41 is an external gear. The sun gear 41 is connected to the first electric generator 71. The ring gear 42 is an internal gear, coaxial with the sun gear 41. Each pinion 43 is located between the sun gear 41 and the ring gear 42. Each pinion 43 meshes with both the sun gear 41 and the ring gear 42. The gear carrier 44 supports the pinions 43. The pinions 43 are capable of rotation and can revolve around a central axis by rotating together with the gear carrier 44. The gear carrier 44 is connected to the crankshaft 12.

[0022] The gear shaft 45 is connected to the gear ring 42. Furthermore, the gear shaft 45 is connected to the drive wheel 64 via a reduction mechanism 62 and a differential mechanism 63. The reduction mechanism 62 outputs the rotational speed of the gear shaft 45 at a reduced speed. The differential mechanism 63 allows for a speed difference between the left and right drive wheels 64.

[0023] The second planetary gear mechanism 50 includes a sun gear 51, a ring gear 52, multiple pinions 53, a gear carrier 54, and a housing 55. The sun gear 51 is an external gear. The sun gear 51 is connected to the second electric generator 72. The ring gear 52 is an internal gear, coaxial with the sun gear 51. The ring gear 52 is connected to the ring gear shaft 45. Each pinion 53 is located between the sun gear 51 and the ring gear 52. Each pinion 53 meshes with both the sun gear 51 and the ring gear 52. The gear carrier 54 supports the pinions 53. The pinions 53 are capable of rotation. The gear carrier 54 is fixed to the housing 55. Therefore, the pinions 53 are in a state where they cannot revolve around the sun gear.

[0024] The vehicle 100 is equipped with a battery 75, a first converter 76, and a second converter 77.

[0025] Battery 75 is a rechargeable battery. First converter 76 performs AC-DC power conversion between the first generator 71 and battery 75. Additionally, first converter 76 adjusts the power transfer between the first generator 71 and battery 75. Second converter 77 performs AC-DC power conversion between the second generator 72 and battery 75. Second converter 77 adjusts the power transfer between the second generator 72 and battery 75.

[0026] The vehicle 100 is equipped with an air flow meter 81, an intake air temperature sensor 82, an exhaust air temperature sensor 83, an air-fuel ratio sensor 84, an accelerator operation sensor 85, and a vehicle speed sensor 86.

[0027] Air flow meter 81 is located upstream of throttle valve 22 in intake passage 21. Air flow meter 81 detects the amount of intake air flowing through intake passage 21 per unit time, i.e., intake air volume GA. Intake air temperature sensor 82 detects the temperature of the intake air flowing through intake passage 21, i.e., intake air temperature TI. Exhaust temperature sensor 83 detects the temperature of the exhaust gas flowing through exhaust passage 26 and into filter 28, i.e., exhaust temperature TO. Air-fuel ratio sensor 84 detects the exhaust air-fuel ratio AF of the exhaust gas flowing through exhaust passage 26 and into filter 28. Accelerator operation amount sensor 85 detects the amount of accelerator pedal operation by the driver, i.e., accelerator operation amount ACC. Vehicle speed sensor 86 detects the vehicle speed at 100, i.e., vehicle speed V.

[0028] <Control Device>

[0029] Vehicle 100 is equipped with a control device 90. The control device 90 controls vehicle 100. The control device 90 obtains a signal indicating the intake air volume GA from air flow meter 81. The control device 90 obtains a signal indicating the intake air temperature TI from intake air temperature sensor 82. The control device 90 obtains a signal indicating the exhaust air temperature TO from exhaust air temperature sensor 83. The control device 90 obtains a signal indicating the exhaust air-fuel ratio AF from air-fuel ratio sensor 84. The control device 90 obtains a signal indicating the accelerator operation amount ACC from accelerator operation amount sensor 85. The control device 90 obtains a signal indicating the vehicle speed V from vehicle speed sensor 86. The control device 90 obtains signals indicating the current IB and temperature TB of battery 75 from battery 75.

[0030] The control device 90 includes a CPU 91, peripheral circuits 92, ROM 93, storage device 94, and bus 95. Bus 95 connects the CPU 91, peripheral circuits 92, ROM 93, and storage device 94 to enable communication between them. Peripheral circuits 92 include circuits for generating clock signals that define internal operations, power supply circuits, reset circuits, etc. ROM 93 pre-stores various programs used by the CPU 91 to execute various controls. The CPU 91 controls the vehicle 100 by executing the various programs stored in ROM 93.

[0031] Vehicle Control

[0032] CPU 91 calculates the required driving force for vehicle 100 based on the accelerator operation (ACC) and vehicle speed (V). Based on this required driving force, CPU 91 determines the torque distribution among the internal combustion engine 10, the first electric generator 71, and the second electric generator 72. Based on this torque distribution, CPU 91 controls the output of the internal combustion engine 10 and the power operation and regeneration of the first and second electric generators 71 and 72.

[0033] Based on the torque distribution among the internal combustion engine 10, the first electric generator 71, and the second electric generator 72, the CPU 91 calculates the target output value of the internal combustion engine 10. The CPU 91 then outputs control signals to the internal combustion engine 10 based on this target output value to control the throttle opening 22, the fuel injection quantity from the fuel injection valve 23, and the ignition timing of the spark plug 24. Furthermore, the CPU 91 controls the first electric generator 71 via the first converter 76 by outputting control signals to the first converter 76. Finally, the CPU 91 controls the second electric generator 72 via the second converter 77 by outputting control signals to the second converter 77.

[0034] The CPU 91 calculates the battery 75's state of charge (SOC) and input limit value Win based on the torque distribution. The CPU 91 calculates the SOC based on the cumulative value of the current IB. Furthermore, the CPU 91 calculates the maximum allowable charge to the battery 75, i.e., the input limit value Win, based on the calculated SOC and the battery temperature TB. The input limit value Win is represented by a zero or positive value; the larger the absolute value, the greater the allowable charge to the battery 75. The CPU 91 determines the torque distribution among the internal combustion engine 10, the first electric generator 71, and the second electric generator 72 in a manner that maintains the battery 75's SOC within a certain control range.

[0035] <Accumulation Calculation and Processing>

[0036] CPU 91 performs a calculation process to determine the accumulation amount of particulate matter captured by filter 28, i.e., the PM accumulation amount DA. CPU 91 repeatedly executes the program stored in ROM 93 for calculating the PM accumulation amount DA at predetermined cycles. The accumulation amount calculation process is implemented by CPU 91, for example, repeatedly executing the program stored in ROM 93 for calculating the PM accumulation amount DA.

[0037] When CPU91 begins the program for calculating PM accumulation amount DA, it repeatedly calculates PM generation and PM regeneration. Then, CPU91 calculates the PM accumulation amount DA by updating the PM accumulation amount DA. Specifically, CPU91 calculates the difference between PM generation and PM regeneration and adds it to the value of PM accumulation amount DA before the update, and uses this sum as the latest value of PM accumulation amount DA, thus updating the PM accumulation amount DA.

[0038] PM generation is the amount of particulate matter generated by the combustion of the gas mixture in cylinder 11. CPU 91 calculates the PM generation based on the intake air volume GA, fuel injection volume, etc.

[0039] PM regeneration is the amount of particulate matter burned within filter 28. The higher the temperature of the exhaust gas flowing into filter 28, i.e., exhaust temperature TO, the higher the temperature of filter 28. Therefore, the temperature of filter 28 can be determined from the temperature detected by exhaust temperature sensor 83. CPU 91 uses a heat budget model of filter 28 based on the flow rate of exhaust gas flowing into filter 28, exhaust temperature TO, and outside air temperature to calculate the temperature of filter 28, i.e., filter temperature TF. Furthermore, the flow rate of exhaust gas flowing into filter 28 can be determined from the intake air volume GA and fuel injection volume. Additionally, the outside air temperature can be determined using the intake air temperature TI detected by intake air temperature sensor 82. When the filter temperature TF is above the ignition point of particulate matter, oxygen-containing exhaust gas flows into filter 28, causing the particulate matter accumulated in filter 28 to burn. Combustion of particulate matter requires oxygen, so the amount of particulate matter burned within filter 28 at this time depends on the amount of oxygen in the exhaust gas flowing into filter 28. The oxygen concentration of the exhaust gas flowing into filter 28 can be determined from the detection results of air-fuel ratio sensor 84. Therefore, the CPU91 calculates the PM regeneration amount based on the exhaust temperature TO detected by the exhaust temperature sensor 83, the oxygen concentration (i.e., exhaust air-fuel ratio AF) detected by the air-fuel ratio sensor 84, the intake air volume GA, and the fuel injection amount.

[0040] <Including a series of processes such as regeneration>

[0041] CPU91 performs regeneration control, including filter regeneration, ignition, shutdown, and deceleration force adjustment. When the PM buildup DA exceeds a predetermined buildup amount DAS, CPU91 executes a program stored in ROM93 for regeneration control. In other words, regeneration control is achieved by CPU91 executing a program stored in ROM93 for regeneration control when the PM buildup DA exceeds the predetermined buildup amount DAS. The predetermined buildup amount DAS, defined as "the amount at which filter regeneration should be performed when a considerable amount of particulate matter has been captured in filter 28," is determined in advance through experiments and simulations.

[0042] Specifically, such as Figure 2 As shown, after the CPU 91 starts the program for controlling regeneration, it first executes step S11. In step S11, the CPU 91 starts the deceleration force adjustment process. In the deceleration force adjustment process, the CPU 91 first sets the target value SOCT of the battery 75's charge rate SOC to be smaller than before the start of regeneration control. The target value SOCT is the value between the upper and lower limits of the control range of charge rate SOC. By setting the target value SOCT to be smaller than before, the control range of charge rate SOC shifts upward towards the lower value side. Therefore, the CPU 91 controls the vehicle 100 in a way that keeps the battery 75's charge rate SOC within a range that has shifted upward towards the lower value side compared to the control range before the start of regeneration control.

[0043] Next, CPU 91 sets the input upper limit value Win to a value greater than the value before the start of regeneration control. This increases the power output of the second electric generator 72 when it functions as a generator. Consequently, the regenerative braking force, i.e., the deceleration force, corresponding to the power output of the second electric generator 72 can also be increased. Afterward, CPU 91 proceeds the process to step S12.

[0044] In step S12, CPU 91 determines whether the regeneration conditions for the filter regeneration process are met. The regeneration conditions include "vehicle 100 is decelerating." Specifically, CPU 91 stores the timing data of vehicle speed V obtained from vehicle speed sensor 86 in storage device 94. Then, based on the timing data of vehicle speed V, CPU 91 determines whether vehicle 100 is decelerating. If the regeneration conditions are not met (S12: No), CPU 91 repeats step S12. On the other hand, if the regeneration conditions are met (S12: Yes), CPU 91 proceeds to step S13. Furthermore, if the regeneration conditions are no longer met after determining in step S12 that the regeneration conditions have been met, CPU 91 cancels all subsequent processing after the regeneration control and ends the regeneration control.

[0045] In step S13, CPU91 performs a filter regeneration process. The filter regeneration process is a process that burns the particulate matter captured by filter 28. Furthermore, step S13 is performed when the start conditions controlled during regeneration are met and a positive determination is made in step S12. Therefore, the filter regeneration process in step S13 is performed under the conditions that the PM accumulation amount DA is above a predetermined accumulation amount DAS and the vehicle 100 is in a deceleration period.

[0046] The aforementioned filter regeneration process includes a heating process and an oxygen supply process. The heating process involves raising the temperature of the filter 28 to a predetermined or higher temperature. As part of the heating process, the CPU 91 stops combustion in the cylinder 11 by stopping the spark ignition of the spark plug 24. Based on this, fuel injection is performed from the fuel injection valve 23. In addition, the CPU 91 controls the throttle valve 22 to allow air to flow in the intake passage 21. As a result, the fuel-containing air-fuel mixture flows into the exhaust passage 26 without combustion in the cylinder 11. When the unburned air-fuel mixture flows into the exhaust passage 26, it is combusted in the catalyst 27. Furthermore, in this fuel injection, only an amount of fuel that can be completely reacted in the catalyst 27 is injected to prevent the injected fuel from passing through the catalyst 27 and being discharged downstream.

[0047] In this manner, the CPU91 injects fuel, generating heat in the catalyst 27. Then, the CPU91 uses the exhaust gas flowing in the exhaust passage 26 as a medium to transfer the heat generated in the catalyst 27 downstream. When the heat generated in the catalyst 27 is transferred to the filter 28 in this way, and the temperature of the filter 28 becomes above the ignition point of the particulate matter, the particulate matter accumulated in the filter 28 can be burned.

[0048] The oxygen supply process involves supplying oxygen to the filter 28 after the heating process has been completed, thereby causing the particulate matter trapped in the filter 28 to burn. During the oxygen supply process, the CPU 91 stops the spark ignition of the spark plug 24 and stops fuel injection from the fuel injection valve 23. Simultaneously, the CPU 91 controls the throttle valve 22 to allow air to flow in the intake passage 21. Air is then fed into the filter 28 by a pump action (not shown) where a piston moves up and down within the cylinder 11. Furthermore, the oxygen supply process is performed under the condition that the filter temperature TF reaches or exceeds a predetermined temperature. This predetermined temperature is above the ignition point of the particulate matter. In this manner, the CPU 91 begins the filter regeneration process. Afterward, the CPU 91 proceeds the process to step S14.

[0049] In step S14, CPU91 determines whether the filter temperature TF is above the temperature threshold TTH. The temperature threshold TTH is a value higher than a specified temperature. The temperature threshold TTH is determined in advance through experiments and simulations, as the temperature at which the particulate matter accumulated on filter 28 may melt. If the filter temperature TF is less than the temperature threshold TTH (S14: No), CPU91 repeats step S14. On the other hand, if the filter temperature TF is above the temperature threshold TTH (S14: Yes), CPU91 proceeds to step S15.

[0050] In step S15, CPU91 terminates the filter regeneration process. Then, the process proceeds to step S16.

[0051] In step S16, the CPU 91 performs an ignition process. The ignition process involves injecting fuel from the fuel injection valve 23 and igniting it through the spark plug 24. Furthermore, during the ignition process, the CPU 91 sets the ignition timing of the spark plug 24 to be delayed compared to the case where no ignition process is performed. Moreover, in this ignition process, fuel is injected at a lower amount than when the internal combustion engine 10 is idling. Idling is the minimum operating state in which the internal combustion engine 10 can operate autonomously and continuously. Furthermore, as described above, step S16 is performed under conditions where regeneration conditions are met. Therefore, the ignition process is performed with the filter temperature TF being above the temperature threshold TTH and the vehicle 100 being in a deceleration phase.

[0052] Thus, through steps S15 and S16, CPU91 terminates the filter regeneration process and begins the ignition process. Afterward, CPU91 proceeds the process to step S17.

[0053] In step S17, the CPU91 determines whether the filter temperature TF is below the predetermined target temperature TTL. The target temperature TTL is the temperature at which the filter 28 has been sufficiently cooled, and is determined in advance through experiments and simulations. If the filter temperature TF is higher than the target temperature TTL (S17: No), the CPU91 returns the process to step S16. Therefore, the higher the filter temperature TF, the longer the ignition process takes until it reaches the target temperature TTL. On the other hand, if the filter temperature TF is below the target temperature TTL (S17: Yes), the CPU91 proceeds the process to step S18.

[0054] In step S18, CPU91 determines whether the vehicle speed V is below a predetermined speed VT. The predetermined speed VT is the minimum vehicle speed V required to supply the air needed for the regeneration process to the filter 28 after the regeneration process in step S13 has been performed, and is determined in advance through testing and simulation. If the vehicle speed V is below the predetermined speed VT (S18: Yes), CPU91 proceeds the process to step S19.

[0055] In step S19, CPU 91 terminates the ignition process and executes a stop process. The stop process is a process that stops the rotation of the crankshaft 12 of the internal combustion engine 10. Specifically, in the stop process, CPU 91 stops the ignition of the spark plug 24. In addition, CPU 91 stops the injection of fuel from the fuel injection valve 23. Furthermore, CPU 91 controls the throttle valve 22 to stop the flow of air in the intake passage 21. Then, CPU 91 controls the first electric generator 71 and the second electric generator 72 so that the rotation of the crankshaft 12 becomes zero while satisfying the vehicle's required driving force. Moreover, as described above, step S19 is a process performed after the process of step S16, under the condition that the regeneration conditions are met. Therefore, the stop process is a process performed with the condition that the vehicle 100 is in a deceleration period after the ignition process. After step S19, CPU 91 proceeds the process to step S20.

[0056] In step S20, CPU 91 determines whether the vehicle speed V is zero. If the vehicle speed V is not zero (S20: No), CPU 91 repeatedly performs the process in step S20. On the other hand, if the vehicle speed V is zero (S20: Yes), CPU 91 moves the process to step S21.

[0057] In step S21, CPU91 terminates the deceleration force adjustment process. That is, CPU91 returns (restores) the target value SOCT, which serves as the control center for the battery's SOC (State of Charge) of the battery 75, to its value before the start of regeneration control. Additionally, CPU91 returns (restores) the input upper limit value Win to its value before the start of regeneration control. Afterward, CPU91 terminates a series of processes in the regeneration control.

[0058] If the vehicle speed V is greater than the specified speed VT in step S18 (S18: No), CPU 91 returns the process to step S12. That is, CPU 91 executes the filter regeneration process of step S13 again if the following conditions are met: after the ignition process in step S16, the vehicle 100 is in a deceleration period, the PM accumulation amount DA is greater than the specified accumulation amount DAS, and the vehicle speed V is greater than the specified speed VT.

[0059] Furthermore, after regeneration control begins, if the PM accumulation amount DA becomes less than the specified accumulation amount DAS, the CPU91 will cancel all subsequent processing during regeneration control and terminate the regeneration control.

[0060] <The Role of the Implementation Method>

[0061] Taking the case of vehicle 100 decelerating after traveling at a constant speed as an example, the effect of the above implementation method is explained.

[0062] Assuming Figure 3 As shown in (a), during the period from time t1 to time t2, vehicle 100 travels at a constant speed V. Figure 3 As shown in (g), the PM accumulation amount DA gradually increases as the vehicle travels at speed 100. Furthermore, it is assumed that at time t1, the PM accumulation amount DA becomes the predetermined accumulation amount DAS.

[0063] When the PM buildup amount DA reaches or exceeds the specified buildup amount DAS, CPU91 executes the program for regeneration control. Then, at time t1, CPU91 begins deceleration force adjustment processing. Thus, as... Figure 3 As shown in (e), the target value SOCT of the battery 75's SOC is set to be smaller than the value before control during regeneration. Additionally, as... Figure 3 As shown in (f), the input upper limit value Win is set to a value greater than the value before the start of regeneration control. Thereafter, the power that can be generated by the first electric generator 71 and the second electric generator 72 increases, and as a result, the deceleration force that can be generated by the first electric generator 71 and the second electric generator 72 also increases.

[0064] Then, assuming as Figure 3 As shown in (a), at time t2, vehicle 100 begins to decelerate. Figure 3 As shown in (b), at time t2, CPU91 considers the filter regeneration process to be complete and begins the filter regeneration process. Furthermore, in Figure 3 In (b), ON indicates that the filter regeneration process is in progress, and OFF indicates that the filter regeneration process is not in progress. Additionally, as... Figure 3 As shown in (c), the filter temperature TF begins to rise from time t2. Furthermore, as... Figure 3 As shown in (d), the output of the internal combustion engine 10 is positive before time t2 due to combustion in the cylinder 11, meaning it becomes the driving force. On the other hand, the output of the internal combustion engine 10 becomes negative after time t2 because combustion no longer occurs in the cylinder 11, meaning it becomes the deceleration force. Furthermore, as... Figure 3 As shown in (g), the PM accumulation DA begins to decrease from time t2.

[0065] Then, assuming as Figure 3 As shown in (c), at time t3, the filter temperature TF reached the temperature threshold TTH. Therefore, CPU91 terminated the filter regeneration process and began the ignition process. Thus, as... Figure 3 As shown in (b), the filter regeneration process ends at time t3. During this ignition process, the fuel injection amount is less than that during idling. That is, the torque obtained through fuel combustion is insufficient to overcome the frictional forces and other resistances at various points in the internal combustion engine 10. Therefore, as... Figure 3 As shown in (d), at time t3, the output of the internal combustion engine 10 is greater than that during the filter regeneration process from time t2 to time t3, and is negative. As a result, the output of the internal combustion engine 10 during the ignition process becomes a weaker deceleration force than the output of the internal combustion engine 10 during the filter regeneration process.

[0066] After that, as Figure 3 As shown in (d), the ignition process ends at time t4. Figure 3 As shown in (c), at time t4, the filter temperature TF becomes lower than at time t3. Additionally, as... Figure 3 As shown in (a), at time t4, the vehicle speed V becomes below the specified speed VT. Therefore, at time t4, because the vehicle speed V is below the specified speed VT, CPU 91 executes a stop process. Thus, the rotation of crankshaft 12 stops, as... Figure 3 As shown in (d), at time t4, the output of the internal combustion engine 10 becomes zero. That is, at time t4, no further deceleration force can be obtained from the internal combustion engine 10. On the other hand, at time t4, as... Figure 3 As shown in (f), the input upper limit value Win of battery 75 is set to a value larger than that before control was initiated when regeneration began. Therefore, the power generation of the first electric generator 71 and the second electric generator 72 is increased when the vehicle 100 decelerates, as they function as generators. Consequently, the regenerative braking force, i.e., the deceleration force, corresponding to the power generation of the first electric generator 71 and the second electric generator 72, is significantly generated in the vehicle 100. Afterwards, although the illustration is omitted, for example, when the vehicle 100 stops and the vehicle speed V becomes zero, the CPU 91 ends the deceleration force adjustment process. Thus, the target value SOCT of the battery charge SOC and the input upper limit value Win return to their values ​​before control was initiated when regeneration began.

[0067] <Effects of the Implementation Method>

[0068] (1) According to the above embodiment, the CPU 91 executes a stop process that stops the drive of the internal combustion engine 10 after the ignition process is completed. Therefore, when the vehicle 100 is in a deceleration period after the ignition process is completed and the sound and vibration of the intake and exhaust of the internal combustion engine 10 are easily noticeable, the crankshaft 12 does not rotate. In other words, under the above conditions, no sound and vibration of the intake and exhaust of the internal combustion engine 10 are generated.

[0069] (2) According to the above embodiment, the CPU91 performs a stop process when the vehicle speed V is below the predetermined speed VT after the ignition treatment is completed. On the other hand, the CPU91 performs a filter regeneration process again when the vehicle speed V is greater than the predetermined speed VT after the ignition treatment is completed. Therefore, by performing the stop process when the vehicle speed V is low and the sound and vibration are easily noticeable, the noise generated by the vibration of the internal combustion engine 10 can be suppressed. On the other hand, by performing the filter regeneration process again when the vehicle speed V is high and the regeneration process can be performed appropriately, the PM accumulation amount DA can be reduced.

[0070] (3) According to the above embodiment, the CPU91 sets the ignition timing of the spark plug 24 to be delayed during the ignition process compared to the case where no ignition process is performed. Therefore, compared to the case where the ignition timing is assumed to be the same as the case where no ignition process is performed, the amount of heat transferred to the exhaust passage 26 is reduced. Therefore, the heat transferred to the filter 28 during the ignition process can be suppressed. As a result, the filter temperature TF tends to decrease.

[0071] (4) According to the above embodiment, the CPU91 performs the ignition process until the filter temperature TF reaches the target temperature TTL. That is, the higher the filter temperature TF, the longer the CPU91 will perform the ignition process. Therefore, even if the filter temperature TF is relatively high, the filter temperature TF can be sufficiently reduced.

[0072] (5) According to the above embodiment, the CPU 91 performs a deceleration force adjustment process to increase the amount of electricity supplied from the first electric generator 71 and the second electric generator 72 to the battery 75 when the crankshaft 12 of the internal combustion engine 10 stops. Therefore, the maximum value of the deceleration force of the vehicle 100 generated by the electricity generated by the first electric generator 71 and the second electric generator 72 can be increased. As a result, the occurrence of insufficient deceleration force due to stopping the rotation of the crankshaft 12 of the internal combustion engine 10 can be suppressed.

[0073] (6) During the ignition process, the deceleration force generated by the internal combustion engine 10 is smaller in the vehicle 100 compared to the regeneration process. According to the above embodiment, the CPU 91 starts the deceleration force adjustment process before the ignition process begins. As a result, the power that can be supplied to the battery 75 during the ignition process is increased. Therefore, the maximum value of the deceleration force of the vehicle 100 generated by the power generation of the first electric generator 71 and the second electric generator 72 can be increased. As a result, the occurrence of insufficient deceleration force due to stopping the rotation of the crankshaft 12 of the internal combustion engine 10 can also be suppressed during the ignition process.

[0074] (7) In the deceleration force adjustment process of the above embodiment, the target value SOCT of the battery 75's charge rate SOC is set to be smaller than that before the start of regeneration control. Therefore, even if the first electric generator 71 and the second electric generator 72 generate electricity to generate deceleration force during ignition and shutdown processes, it is possible to prevent the battery 75 from becoming overcharged.

[0075] (Other implementation methods)

[0076] The above-described embodiments can be implemented by modification as follows. The above-described embodiments and the following modifications can be combined with each other within the scope of technical inconsistency.

[0077] The timing for performing the deceleration force adjustment process is not limited to the examples of the above embodiments. For example, the CPU91 may perform the deceleration force adjustment process together with the execution of the stop process after the ignition process is completed. That is, the deceleration force adjustment process only needs to be performed during the stop process. Furthermore, the timing for ending the deceleration force adjustment process is not limited to the examples of the above embodiments. For example, the CPU91 may end the deceleration force adjustment process when the vehicle speed V falls below a predetermined speed. The predetermined speed, which is the speed at which sufficient deceleration force of the vehicle 100 can be ensured even without performing the deceleration force adjustment process, can be determined through testing and simulation.

[0078] In the above embodiment, during the deceleration force adjustment process, the power supplied to the battery 75 is increased by increasing the input upper limit value Win, but it can also be achieved without using the input upper limit value Win. For example, it is also possible to limit the power supplied to the battery 75 when the deceleration force adjustment process is not performed, and not to perform such a limitation when the deceleration force adjustment process is performed.

[0079] • In the deceleration force adjustment process of the above embodiment, the process of reducing the target value SOCT of the battery's SOC (State of Charge) can also be omitted. Alternatively, the deceleration force adjustment process can also be omitted.

[0080] • The duration of the ignition treatment can also be constant, independent of the filter temperature TF. For example, it can be performed for a constant period determined in advance through testing or simulation, independent of the filter temperature TF.

[0081] • During ignition treatment, the ignition timing of spark plug 24 can be kept from being delayed. Even in this case, the filter temperature TF can be lowered during ignition treatment compared to the case of regeneration treatment. In addition, during ignition treatment, the variable valve mechanism can be controlled, for example, in the case where the internal combustion engine 10 has a variable valve mechanism, to prevent the heat generated by combustion in cylinder 11 from flowing to exhaust passage 26.

[0082] • After the fire treatment is completed, the filter regeneration process may not need to be performed again. In other words, after the fire treatment is completed, the CPU91 can perform the shutdown process regardless of the vehicle speed V.

[0083] The calculation of the accumulation amount is not limited to the examples of the above embodiments; any method that can calculate the PM accumulation amount DA is acceptable. For example, the PM accumulation amount DA can also be calculated based on the pressure difference before and after filter 28.

[0084] • In the filter regeneration process, fuel supply to other cylinders 11 can be continued while fuel supply to some cylinders 11 is stopped.

[0085] Regarding the configuration of the control device 90, it is not limited to the examples of the above embodiments. The control device 90 may be a processing circuit having one or more processors that perform various processes according to a computer program (software). Furthermore, the control device 90 may also be a processing circuit having dedicated hardware circuits such as application-specific integrated circuits (ASICs) or combinations thereof that perform at least some of the various processes. The processor includes a CPU 91 and memories such as RAM and ROM 93. The memories store program code or instructions configured to cause the CPU 91 to perform processes. Memory, i.e., computer-readable media, includes all available media that can be accessed by a general-purpose or special-purpose computer.

[0086] • In the above embodiments, the configuration of the vehicle 100 can also be appropriately modified. For example, the internal combustion engine 10 can have three or fewer cylinders 11, or it can have five or more cylinders 11.

Claims

1. A control device of a vehicle adapted for a vehicle in which, the vehicle is provided with: an internal combustion engine having a cylinder, a fuel injection valve that injects fuel into the cylinder, a spark plug that ignites in the cylinder, an exhaust passage through which exhaust gas from the cylinder flows, and a filter that traps particulate matter contained in the exhaust gas; a motor generator that is linked to a crankshaft of the internal combustion engine; and a battery that is supplied with electric power from the motor generator, the control device is configured to execute a deposit amount calculation process, a filter regeneration process, an ignition process, and a stop process that stops rotation of the crankshaft of the internal combustion engine, the deposit amount calculation process is a process of calculating a deposit amount of the particulate matter trapped by the filter, i.e., a PM deposit amount, the filter regeneration process is a process of combusting the particulate matter trapped by the filter while stopping injection of fuel from the fuel injection valve while the crankshaft of the internal combustion engine is rotating, as a condition that the PM deposit amount is equal to or greater than a predetermined prescribed deposit amount and that the vehicle is in a deceleration period, the ignition process is a process of ending the filter regeneration process and injecting fuel from the fuel injection valve and igniting by the spark plug as a condition that the temperature of the filter is equal to or greater than a predetermined temperature threshold and that the vehicle is in a deceleration period, the control device is configured to, execute the stop process as a condition that the vehicle is in a deceleration period and that the speed of the vehicle is equal to or less than a predetermined prescribed speed after the ignition process ends, re-execute the filter regeneration process as a condition that the PM deposit amount is equal to or greater than the predetermined prescribed deposit amount, that the vehicle is in a deceleration period, and that the speed of the vehicle is greater than the prescribed speed after the ignition process ends, the prescribed speed is a minimum vehicle speed at which air required for the filter regeneration process can be supplied to the filter in a case where the filter regeneration process is executed.

2. The control device of a vehicle according to claim 1, the control device is configured to delay the ignition timing of the spark plug in the ignition process compared to a case where the ignition process is not executed.

3. The control device of a vehicle according to claim 1, the control device is configured to execute the ignition process for a longer period as the temperature of the filter is higher.

4. The control device of a vehicle according to claim 1, the control device is configured to further execute a deceleration force adjustment process that is a process for making the electric power that can be supplied from the motor generator to the battery larger when the stop process is executed compared to a case where the stop process is not executed.

5. The control device of a vehicle according to claim 4, the control device is configured to start the deceleration force adjustment process before starting execution of the ignition process.

6. A control method of a vehicle adapted for a vehicle in which, the vehicle is provided with: An internal combustion engine having a cylinder, a fuel injection valve that injects fuel into the cylinder, a spark plug that ignites in the cylinder, an exhaust passage through which exhaust gas from the cylinder flows, and a filter that traps particulate matter contained in the exhaust gas; An electric motor generator that is coupled to a crankshaft of the internal combustion engine; and A battery that is supplied with electric power from the electric motor generator The control method includes: A PM accumulation amount calculation process that calculates a PM accumulation amount of the particulate matter trapped by the filter; A filter regeneration process that, as conditions, the PM accumulation amount is equal to or greater than a predetermined prescribed accumulation amount and the vehicle is in a deceleration period, stops injection of fuel from the fuel injection valve while rotating the crankshaft of the internal combustion engine, thereby combusting the particulate matter trapped by the filter; An ignition process that, as conditions, the temperature of the filter is equal to or greater than a predetermined temperature threshold and the vehicle is in a deceleration period, ends the filter regeneration process and injects fuel from the fuel injection valve and ignites by the spark plug; and In the control method, A stop process that stops rotation of the crankshaft of the internal combustion engine is executed as a condition that the vehicle is in a deceleration period and the speed of the vehicle is equal to or less than a predetermined prescribed speed after the ignition process ends, The filter regeneration process is executed again as a condition that the PM accumulation amount is equal to or greater than the predetermined prescribed accumulation amount, the vehicle is in a deceleration period, and the speed of the vehicle is greater than the prescribed speed after the ignition process ends, The prescribed speed is a minimum vehicle speed at which air required for the filter regeneration process can be supplied to the filter when the filter regeneration process is executed. ​

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