Control device for a vehicle

Abstract

The objective of this invention is to suppress driver discomfort caused by changes in deceleration due to the cessation of motor drive. The vehicle includes: an internal combustion engine, wherein a gas permeable powder (GPF) is installed in the exhaust pipe to trap particulate matter in the exhaust; and a first electric generator that performs motor drive to rotate the crankshaft of the internal combustion engine. During fuel cut-off of the internal combustion engine, a control device performs a regeneration process to regenerate the GPF by performing motor drive. During the regeneration process, when the driver of the vehicle performs an operation requiring deceleration, if the temperature of the GPF is above a predetermined temperature, the control device performs a process to stop motor drive and perform ignition combustion to burn the air-fuel mixture.

Description

Technical Field

[0001] This invention relates to a vehicle control device. Background Technology

[0002] In the vehicle described in Patent Document 1, a filter installed in the exhaust passage is regenerated by driving an internal combustion engine that is in a state of fuel cut-off using an electric motor.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2024-4038 Summary of the Invention

[0004] If the filter temperature becomes too high during regeneration, it is preferable to stop the motor drive to prevent damage to the filter. However, stopping the motor drive will change the vehicle's deceleration, which may cause discomfort to the driver.

[0005] The vehicle control device for solving the above-mentioned problems is applicable to vehicles comprising: an internal combustion engine, wherein a filter for capturing particulate matter in exhaust gas is disposed in the exhaust passage; and an electric motor that drives the crankshaft of the internal combustion engine to rotate. During fuel cut-off of the internal combustion engine, the control device performs a regeneration process by driving the electric motor to regenerate the filter, and during the regeneration process, when the driver of the vehicle performs an operation requiring deceleration, if the temperature of the filter is above a predetermined temperature, it performs a process of stopping the electric motor drive and performing ignition combustion to burn the air-fuel mixture.

[0006] Invention Effects

[0007] The vehicle's control system can suppress the discomfort caused to the driver by changes in deceleration due to the cessation of motor drive. Attached Figure Description

[0008] Figure 1 This is a schematic diagram illustrating the configuration of a vehicle in one implementation method.

[0009] Figure 2 This is a flowchart illustrating the steps of the processing performed by the control device in this embodiment. Detailed Implementation

[0010] The following describes one embodiment of the vehicle control device.

[0011] <Vehicle Composition>

[0012] like Figure 1 As shown, vehicle 500 is equipped with an internal combustion engine 10.

[0013] The internal combustion engine 10 includes a cylinder block 11, a cylinder head 12, and a cylinder head cover 13.

[0014] A cylinder 16, which constitutes the cylinder of an internal combustion engine 10, is provided inside the cylinder block 11. A piston 15 is disposed inside the cylinder 16.

[0015] The cylinder head 12 is provided with an intake port 30 for introducing intake air into the combustion chamber 17 of the internal combustion engine 10 and an exhaust port 70 for discharging exhaust gas from the combustion chamber 17.

[0016] An intake valve 81 is provided at the intake port 30. The drive system of the intake valve 81 is provided with a variable valve mechanism, namely the intake-side variable valve mechanism 85, which changes the valve opening and closing times of the intake valve 81.

[0017] An exhaust valve 82 is provided at the exhaust port 70. The drive system of the exhaust valve 82 is provided with a variable valve mechanism, namely an exhaust-side variable valve mechanism 86, which changes the valve opening and closing times of the exhaust valve 82.

[0018] The internal combustion engine 10 is equipped with an in-cylinder fuel injection valve 84 that injects fuel into the combustion chamber 17. Furthermore, a spark plug 23 is provided on the cylinder head 12.

[0019] A crankcase 19 is provided at the lower part of the cylinder block 11 to house the crankshaft 18, which serves as the output shaft of the internal combustion engine 10.

[0020] An intake manifold 29 with a pressure regulating chamber 60 is connected upstream of the intake port 30, and an intake pipe 20 is connected upstream of the pressure regulating chamber 60. The intake pipe 20, the pressure regulating chamber 60, the intake manifold 29, and the intake port 30 constitute the intake passage of the internal combustion engine 10.

[0021] In the intake manifold 20, from upstream, are arranged an air filter 21, an air flow meter 51, a compressor impeller 24C of a turbocharger 24 driven by exhaust gas from the combustion chamber 17, an intercooler 27, a boost pressure sensor 54, and a throttle valve 28. An intake pressure sensor 55 is also installed on the pressure regulating chamber 60. The throttle valve 28 adjusts the amount of air intake by changing its opening degree via an electric motor. Furthermore, the smaller the opening degree of the throttle valve 28, the less air passes through it.

[0022] Air filter 21 filters the intake air entering the intake manifold 20. Turbocharger 24 pressurizes the air within the intake manifold 20. Intercooler 27 cools the air after it passes through compressor impeller 24C. Throttle valve 28 regulates the amount of air intake by adjusting its opening.

[0023] Air flow meter 51 detects the intake air volume GA. Furthermore, boost pressure sensor 54 detects the pressure downstream of compressor impeller 24C in intake pipe 20, i.e., boost pressure PTC. Additionally, intake pressure sensor 55 detects the pressure within pressure regulating chamber 60, i.e., intake pressure PIM. Intake pressure PIM is the pressure in the intake passage further downstream of throttle valve 28.

[0024] Downstream of the exhaust port 70 is an exhaust pipe 90 that forms an exhaust passage. Midway through the exhaust pipe 90 is a housing that houses the turbine impeller 24T of the turbocharger 24.

[0025] In the exhaust pipe 90, a three-way catalyst 40 is located downstream of the turbine impeller 24T. This three-way catalyst 40 oxidizes the hydrocarbons (HC) and carbon monoxide (CO) contained in the exhaust gas to produce water and carbon dioxide. Furthermore, the three-way catalyst 40 reduces the nitrogen oxides (NOx) contained in the exhaust gas to produce nitrogen.

[0026] In the exhaust pipe 90, a gasoline particulate filter (hereinafter referred to as GPF) 41 is installed downstream of the three-way catalytic converter 40. GPF 41 is a filter that carries the three-way catalytic converter on the filter that captures particulate matter (hereinafter referred to as PM) in the exhaust.

[0027] The control device 100 includes a CPU 110, a memory 120, etc. The CPU 110 implements various controls of the internal combustion engine 10 by executing the program stored in the memory 120.

[0028] The crankshaft 18 is mechanically connected to the planet carrier C of the planetary gear mechanism 300 that constitutes the power distribution device.

[0029] The rotating shaft 310a of the first electric generator 310 is mechanically connected to the sun gear S of the planetary gear mechanism 300. The first electric generator 310 functions as a generator that generates electricity using the output of the internal combustion engine, and also functions as a starter that drives the crankshaft 18 to rotate when the internal combustion engine 10 is started. This first electric generator 310 is an electric motor that drives the crankshaft 18 to rotate.

[0030] The rotating shaft 320a of the second electric generator 320 and the drive wheel 400 are mechanically connected to the ring gear R of the planetary gear mechanism 300.

[0031] The second electric generator 320 functions as an electric motor that generates driving force for the drive wheel 400, and also functions as a generator that generates regenerative power when the vehicle decelerates.

[0032] An AC voltage is applied to the terminals of the first electric generator 310 by the inverter 330. Furthermore, an AC voltage is applied to the terminals of the second electric generator 320 by the inverter 340. Thus, the vehicle of this embodiment is equipped with a hybrid power system that uses an internal combustion engine 10 and an electric generator as prime movers.

[0033] The control device 100 operates various controllable devices, including the throttle valve 28, fuel injection valve 84, spark plug 23, intake-side variable valve timing mechanism 85, and exhaust-side variable valve timing mechanism 86. Furthermore, the control device 100 operates the inverter 330 to control the first electric generator 310. And, the control device 100 operates the inverter 340 to control the second electric generator 320.

[0034] The control device 100 includes a CPU 110 for performing calculations and a memory 120 for storing control programs and data. Furthermore, the control device 100 executes various control-related processes by having the CPU 110 execute the programs stored in the memory 120. Additionally, although not shown, the control device 100 consists of multiple control units, including a control unit for an internal combustion engine, a control unit for a first electric generator 310, and a control unit for a second electric generator 320.

[0035] The control unit 100 receives detection signals from the air flow meter 51, boost pressure sensor 54, and intake pressure sensor 55. It also receives detection signals from various other sensors. For example, the control unit 100 receives a detection signal from a throttle operation sensor 52, which detects the amount of throttle pedal operation (ACCP), which regulates the output of the internal combustion engine 10. It also receives a detection signal from a throttle valve sensor 53, which detects the throttle valve opening (TA), which determines the opening of the throttle valve 28. Furthermore, the control unit 100 receives a detection signal from a vehicle speed sensor 56, which detects the vehicle speed (SP). It also receives a detection signal from a coolant temperature sensor 57, which detects the temperature of the coolant in the internal combustion engine 10. Finally, the control unit 100 receives a detection signal from a shift position sensor 58, which detects the shift position (SFT). The shift position SFT is the operating position of the shift lever located inside the vehicle 500 and operated by the driver of the vehicle 500. Furthermore, the control device 100 receives a detection signal from the crankshaft angle sensor 50, which detects the rotation angle (crankshaft angle) of the crankshaft 18 for calculating the internal combustion engine speed NE, or a detection signal from the vehicle speed sensor 56, which detects the vehicle speed SP. Additionally, the control device 100 receives an output signal Sm1 from the first rotation angle sensor 350, which detects the rotation angle of the first electric generator 310. Furthermore, the control device 100 receives an output signal Sm2 from the second rotation angle sensor 360, which detects the rotation angle of the second electric generator 320.

[0036] The control device 100 calculates the internal combustion engine load rate KL based on the internal combustion engine speed NE and the intake air volume GA. The internal combustion engine load rate KL is a parameter that determines the amount of air filled into the combustion chamber 17, and is the ratio of the inflow air volume per combustion cycle of a cylinder to a reference inflow air volume. The reference inflow air volume can be set variably according to the internal combustion engine speed NE.

[0037] The control device 100 calculates the required torque for vehicle operation based on the throttle input (ACCP) and vehicle speed (SP). Furthermore, the control device 100 controls the required output torque (Pe) of the internal combustion engine 10, the output torque of the first electric generator 310, and the second electric generator 320 in a manner that satisfies the required torque. For example, when the required output torque (Pe) of the internal combustion engine 10 is "0", the control device 100 implements EV driving (stopping the operation of the internal combustion engine 10 and using the output torque of the second electric generator 320 to drive the vehicle). Conversely, when the required output torque (Pe) of the internal combustion engine 10 is greater than "0", the control device 100 operates the internal combustion engine 10 to obtain internal combustion engine output, and implements hybrid driving (using the internal combustion engine output and the output torque of the second electric generator 320 to drive the vehicle).

[0038] The control device 100 controls the fuel injection of the fuel injection valve 84, the opening of the throttle valve 28, etc. Furthermore, when the output required by the internal combustion engine 10 is "0", the control device 100 performs fuel cut-off to stop fuel injection from the fuel injection valve 84.

[0039] The control device 100 controls the drive of the intake-side variable valve mechanism 85 and the exhaust-side variable valve mechanism 86 based on the internal combustion engine speed NE, internal combustion engine load rate KL, etc.

[0040] The control device 100 switches the driving mode of the vehicle 500 based on the shift position SFT. Driving modes include, for example, the known D mode, the known S mode, and the known B mode. D mode is the basic driving mode. S mode is a driving mode that improves the handling of the vehicle 500 compared to D mode. B mode is a driving mode that improves the deceleration of the vehicle 500 compared to D mode. Furthermore, the selection of each driving mode can also be done by operating a switch located inside the vehicle, rather than by operating the shift lever.

[0041] <Regarding the switch from motor drive to ignition and combustion>

[0042] When the fuel cutoff described above is performed, the control device 100 implements the aforementioned motor drive. By implementing the motor drive, if fresh air is introduced into the high-temperature GPF41, the PM accumulated on the GPF41 is burned by the oxygen contained in the fresh air. The GPF41 is regenerated through this PM combustion.

[0043] If the temperature of GPF41 becomes too high during GPF41 regeneration, the control device 100 switches from motor drive to ignition combustion to prevent damage to GPF41. Ignition combustion is the operation of stopping motor drive and allowing the air-fuel mixture to burn. The control device 100 implements ignition combustion by restarting fuel injection from the fuel injection valve 84. Furthermore, if spark plug 23 discharge is stopped during motor drive, spark plug 23 discharge is restarted in conjunction with the restart of fuel injection from the fuel injection valve 84.

[0044] Here, if the motor drive is stopped, the deceleration of vehicle 500 will change, which may cause discomfort to the driver of vehicle 500. Therefore, control device 100 executes... Figure 2 The processing is shown.

[0045] Figure 2 The diagram shows the steps of the process performed by the control device 100 at a predetermined cycle when the regeneration process of GPF41, driven by the motor described above, begins. Figure 2 The processing shown is implemented by the CPU 110 executing a program stored in the memory 120 of the control device 100. Furthermore, the step numbers of each process will be indicated below by numbers beginning with "S".

[0046] exist Figure 2 In the series of processes shown, the control device 100 determines whether there is a user operation that changes the deceleration (S100). In the S100 process, if the driver of the vehicle 500 requests deceleration, the control device 100 determines that there is a user operation that changes the deceleration. The such operation by the driver requesting deceleration is, for example, selecting the aforementioned B mode as the driving mode of the vehicle 500.

[0047] In the processing of S100, if a user operation indicating a change in deceleration is detected (S100: "Yes"), the control device 100 determines whether the current filter temperature T is above a predetermined judgment value Tref (S110). The filter temperature T is the temperature of the GPF41. The filter temperature T is calculated by the control device 100 based on, for example, the internal combustion engine speed NE and the filling efficiency η. The filter temperature T can be detected using sensors, etc. The filling efficiency η is a value calculated by the control device 100 based on the internal combustion engine speed NE and the intake air volume GA. The aforementioned judgment value Tref is, for example, a value obtained by multiplying the temperature of heat damage to the GPF41 by a predetermined safety factor.

[0048] In the process of S110, if it is determined that the current filter temperature T is not above the predetermined determination value Tref (S110: "No"), the control device 100 executes the aforementioned motor drive (S120). In the process of S120, if the motor drive is currently being executed, the control device 100 continues the motor drive. In the process of S120, if ignition and combustion are currently being executed, the control device 100 stops ignition and combustion and executes the motor drive.

[0049] On the other hand, in the process of S110 described above, if it is determined that the current filter temperature T is above a predetermined determination value Tref (S110: "Yes"), the control device 100 performs the aforementioned ignition combustion (S130) by stopping the motor drive and igniting the air-fuel mixture. In the process of S130, if ignition combustion is currently being performed, the control device 100 continues ignition combustion. In the process of S130, if the motor drive is currently being performed, the control device 100 stops the motor drive and performs ignition combustion.

[0050] Furthermore, if the processing of S120 or S130 is performed, or if the result is negative in the processing of S100, the control device 100 terminates the processing in this cycle.

[0051] <Function and Effects of This Implementation Method>

[0052] During the fuel cutoff period of the internal combustion engine 10, the control device 100 performs a regeneration process to regenerate the GPF41 via electric motor drive. During the regeneration process, if the driver of the vehicle 500 performs a deceleration operation, and the filter temperature T is above a predetermined threshold Tref, the control device 100... Figure 2 S110 shows "Yes", and the process of S130 is executed. The process of S130 is to perform the ignition combustion process of stopping the motor drive and causing the air-fuel mixture to burn. In addition, in this embodiment, the above-mentioned operation of requesting deceleration by the driver is the operation of the driver selecting mode B as the driving mode of vehicle 500.

[0053] Therefore, during the regeneration process, the motor drive is stopped at the exact moment the driver requests a sense of deceleration. This effectively suppresses any discomfort to the driver caused by changes in deceleration due to the cessation of motor drive.

[0054] <Example of Change>

[0055] Furthermore, the above-described embodiments can be modified as follows. The above-described embodiments and the following modifications can be combined with each other within the scope of technical non-contradiction.

[0056] In the processing of S100, the driver's operation to request deceleration is selecting mode B as the driving mode of vehicle 500, but it can also be other operations requesting deceleration. For example, it could be selecting mode S as the driving mode of vehicle 500. Furthermore, if the drive system of vehicle 500 is equipped with a transmission that can change the gear ratio, the driver's operation to request deceleration can also be a downshift operation. A downshift operation is an operation that increases the gear ratio of the transmission.

[0057] The internal combustion engine 10 may not have an intake-side variable valve timing mechanism 85, an exhaust-side variable valve timing mechanism 86, or a turbocharger 24.

[0058] • The vehicle's hybrid system is not limited to Figure 1 The hybrid power system shown can also be other hybrid power systems.

[0059] The number of electric generators in the vehicle can be changed appropriately.

[0060] • The location of GPF41 in exhaust pipe 90 can be appropriately changed.

[0061] • GPF41 can be used as a filter without a three-way catalyst.

[0062] The control device 100 includes a CPU and a memory, and is not limited to performing software processing. For example, the control device 100 may include a dedicated hardware circuit, such as an ASIC, that performs hardware processing on at least a portion of the software processing described in the above embodiments. That is, the control device 100 may include a processing circuit having any of the following configurations (a) to (c): (a) A processing circuit comprising: one or more processing devices that execute all of the above processing according to a program; and one or more program storage devices, such as a ROM, that stores the program. (b) A processing circuit comprising: one or more processing devices that execute a portion of the above processing according to a program and one or more program storage devices; and one or more dedicated hardware circuits that execute the remaining processing. (c) A processing circuit comprising: one or more dedicated hardware circuits that execute all of the above processing. The program storage device, i.e., the computer-readable medium, includes any usable medium that can be accessed by a general-purpose or special-purpose computer.

[0063] Symbol Explanation

[0064] 10-Internal combustion engine, 11-Cylinder block, 12-Cylinder head, 13-Cylinder head cover, 15-Piston, 16-Cylinder, 17-Combustion chamber, 18-Crankshaft, 19-Crankcase, 20-Intake manifold, 21-Air filter, 23-Spark plug, 24-Turbocharger, 24C-Compressor impeller, 24T-Turbine impeller, 27-Intercooler, 28-Throttle valve, 29-Intake manifold, 30-Intake port, 40-Three-way catalytic converter, 41-Gas particulate filter, 41-GPF, 50-Crankshaft angle sensor, 51-Air flow meter, 52-Throttle position sensor, 53-Throttle valve sensor, 54-Boost pressure sensor, 55-Intake pressure sensor, 56- - Vehicle speed sensor, 57- Water temperature sensor, 58- Shift position sensor, 60- Pressure regulating chamber, 70- Exhaust port, 81- Intake valve, 82- Exhaust valve, 84- Fuel injection valve, 85- Intake-side variable valve mechanism, 86- Exhaust-side variable valve mechanism, 90- Exhaust pipe, 100- Control device, 110- CPU, 120- Memory, 300- Planetary gear mechanism, 310- First electric generator, 310a- Rotating shaft, 320- Second electric generator, 320a- Rotating shaft, 330- Inverter, 340- Inverter, 350- First rotation angle sensor, 360- Second rotation angle sensor, 400- Drive wheel, 500- Vehicle.

Claims

1. A control device for a vehicle, the vehicle comprising: an internal combustion engine, wherein a filter for capturing particulate matter in exhaust gas is disposed in an exhaust passage; and an electric motor, which drives the motor to rotate the crankshaft of the internal combustion engine, the control device for the vehicle being characterized in that... During the fuel cut-off of the internal combustion engine, a regeneration process is performed to regenerate the filter by driving the electric motor. During the regeneration process, if the driver of the vehicle performs an operation requiring deceleration and the temperature of the filter is above a predetermined temperature, a process is performed to stop the electric motor drive and perform ignition combustion to burn the air-fuel mixture.

2. The vehicle control device according to claim 1, characterized in that, The operation refers to the driver selecting mode B as the driving mode of the vehicle.

3. The vehicle control device according to claim 1, characterized in that, The operation is a downshifting operation performed by the driver.

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