control device

Abstract

To enable regeneration processing for reducing an amount of particulate matters accumulated on a filter to be effectively conducted.SOLUTION: A vehicle control device comprises: a regeneration processing control section which executes regeneration processing to reduce an amount of particulate matters accumulated on a filter when the amount becomes equal to or larger than a predetermined amount; an SOC increase section which increases an upper limit of an SOC control range while stopping the regeneration processing when a filter temperature becomes equal to or higher than a predetermined temperature during the regeneration processing; and a torque reduction processing section which executes torque reduction processing to reduce a ratio of torque of an internal combustion engine to torque of an electric motor when the SOC reaches the increased upper limit. The regeneration processing control section resumes the regeneration processing when the filter temperature becomes lower than a specified temperature lower than the predetermined temperature after executing the torque reduction processing.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a control device. [Background technology]

[0002] The following Patent Document 1 discloses a technology for halting a fuel cut that is currently being performed to regenerate a filter that captures particulate matter in exhaust gas if the temperature of the filter reaches a predetermined temperature during the fuel cut. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-190358 Summary of the Invention [Problem to be solved by the invention]

[0004] As such, the technology of Patent Document 1 simply stops the ongoing fuel cut when the filter temperature reaches a predetermined temperature, so it is not possible to efficiently lower the filter temperature and therefore not to efficiently perform fuel cut. [Means for solving the problem]

[0005] In order to solve the above-mentioned problems, a control device according to one embodiment is a control device for a vehicle, and includes a regeneration process control unit that executes a regeneration process to reduce the amount of particulate matter deposited on a filter when the amount of deposition becomes equal to or greater than a predetermined value, an SOC expansion processing unit that interrupts the regeneration process and expands the upper limit of the SOC control range when the filter temperature becomes equal to or greater than the predetermined temperature during the regeneration process, and a torque reduction processing unit that executes a torque reduction process to reduce the ratio of the torque of the internal combustion engine to the torque of the electric motor when the SOC reaches the expanded upper limit, and the regeneration process control unit resumes the regeneration process when the filter temperature becomes lower than a specified temperature that is lower than the predetermined temperature after the torque reduction process is executed. [Effects of the Invention]

[0006] According to the control device of one embodiment, it is possible to efficiently execute a regeneration process that reduces the amount of particulate matter deposited on the filter. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram showing a configuration of a vehicle according to an embodiment; [Figure 2] FIG. 2 is a diagram showing a functional configuration related to control of a regeneration process of an ENGECU provided in a vehicle according to an embodiment; [Figure 3] 1 is a flowchart showing a procedure for controlling a regeneration process by an ENGECU provided in a vehicle according to an embodiment; DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0009] (Vehicle 1 configuration) Fig. 1 is a diagram showing the configuration of a vehicle 1 according to one embodiment. The vehicle 1 shown in Fig. 1 is a so-called HEV (Hybrid Electric Vehicle) that includes an engine 10, a first motor generator 52, and a second motor generator 54 as power sources for driving the vehicle 1.

[0010] As shown in FIG. 1, engine 10 has four cylinders #1 to #4. A throttle valve 14 is provided in an intake passage 12 of engine 10. Air drawn into intake passage 12 flows into each combustion chamber 18 of four cylinders #1 to #4 as intake valves 16 open. Fuel is injected into combustion chamber 18 from a direct injection valve 22. The air-fuel mixture in combustion chamber 18 is combusted in response to spark discharge from a spark plug 24. The combustion energy generated at this time is converted into rotational energy of a crankshaft 26.

[0011] When an exhaust valve 28 opens, exhaust gas generated as a result of combustion in the combustion chamber 18 is discharged into an exhaust passage 30. A three-way catalyst 32 having an oxygen storage capacity and a GPF (gasoline particulate filter) 34 are provided in the exhaust passage 30. In this embodiment, an example of the GPF 34 is a filter that collects PM and supports a three-way catalyst.

[0012] The crankshaft 26 is mechanically connected to a carrier C of a planetary gear mechanism 50 that constitutes a power split device. A rotating shaft 52a of a first motor generator 52 is mechanically connected to a sun gear S of the planetary gear mechanism 50. A rotating shaft 54a of a second motor generator 54 and drive wheels 60 are mechanically connected to a ring gear R of the planetary gear mechanism 50. An AC voltage is applied to the first motor generator 52 by a first inverter 56. An AC voltage is applied to the second motor generator 54 by a second inverter 58. The first inverter 56 and the second inverter 58 convert a DC voltage output from a battery 59 into an AC voltage. In this embodiment, a secondary battery such as a lithium-ion secondary battery is used as the battery 59.

[0013] The ENGECU 70 controls the engine 10. For example, the ENGECU 70 controls the throttle valve 14, the in-cylinder injection valve 22, the spark plug 24, and the like in order to control the torque of the engine 10, the ratio of exhaust components, and the like.

[0014] In order to control the engine 10, the ENGECU 70 refers to the intake air amount Ga detected by the air flow meter 80, the output signal Scr of the crank angle sensor 82, the upstream detected value Afu which is the detected value of the upstream air-fuel ratio sensor 84 provided upstream of the three-way catalyst 32, the downstream detected value Afd which is the detected value of the downstream air-fuel ratio sensor 86 provided downstream of the three-way catalyst 32, the pressure Pex of the exhaust gas flowing into the GPF 34 detected by the exhaust pressure sensor 88, and the water temperature THW detected by the water temperature sensor 90.

[0015] The ENGECU 70 is also an example of a "control device" and can control a regeneration process that reduces the amount of PM (an example of "particulate matter") deposited on the GPF 34 (an example of "filter").

[0016] The ENGECU 70 includes a CPU 72, a ROM 74, and a peripheral circuit 76, which are communicatively connected by a communication line 78. The peripheral circuit 76 includes a circuit that generates a clock signal that regulates internal operation, a power supply circuit, a reset circuit, etc. The ENGECU 70 achieves control of the engine 10 by the CPU 72 executing a program stored in the ROM 74. The ENGECU 70 is further communicatively connected to the MGECU 100 and the HVECU 120.

[0017] The MGECU 100 controls the rotation speed of the first motor generator 52 by controlling the first inverter 56. The MGECU 100 also controls the rotation speed of the second motor generator 54 by controlling the second inverter 58. To control the first inverter 56 and the second inverter 58, the MGECU 100 refers to an output signal Sm1 of a first rotation angle sensor 110 that detects the rotation angle of the first motor generator 52 and an output signal Sm2 of a second rotation angle sensor 112 that detects the rotation angle of the second motor generator 54.

[0018] The MGECU 100 includes a CPU 102, a ROM 104, and a peripheral circuit 106, which are communicatively connected by a communication line 108. The MGECU 100 realizes control of the first motor generator 52 and the second motor generator 54 by the CPU 102 executing a program stored in the ROM 104.

[0019] The HVECU 120 controls the hybrid system including the engine 10, the first motor generator 52, and the second motor generator 54 via the ENGECU 70 and the MGECU 100. In order to control the hybrid system, the HVECU 120 refers to the accelerator operation amount ACCP detected by the accelerator sensor 130 and the output signal Sp of the output side rotation angle sensor 132 that detects the rotation angle of the ring gear R.

[0020] The HVECU 120 includes a CPU 122, a ROM 124, and a peripheral circuit 126, which are communicatively connected by a communication line 128. The HVECU 120 controls the hybrid system by the CPU 122 executing a program stored in the ROM 124.

[0021] (Functional configuration for controlling the playback process of ENGECU70) FIG. 2 is a diagram showing a functional configuration related to control of the regeneration process of the ENGECU 70 provided in the vehicle 1 according to one embodiment.

[0022] As shown in FIG. 2, the ENGECU 70 includes an accumulation amount calculation unit 210, a temperature calculation unit 211, a regeneration process control unit 201, an SOC increase processing unit 202, and a torque reduction processing unit 203 for the regeneration process to reduce the amount of PM accumulated in the GPF 34.

[0023] The accumulation amount calculation unit 210 calculates the amount of PM accumulated in the GPF 34. For example, the accumulation amount calculation unit 210 calculates the amount of PM in the exhaust gas based on the rotation speed NE, charging efficiency η, and water temperature THW of the crankshaft 26 of the engine 10, and can calculate the amount of PM accumulated in the GPF 34 based on the rotation speed NE, charging efficiency η, filter temperature Tgpf of the GPF 34, and the amount of PM in the exhaust gas. The charging efficiency η is a parameter that indicates the magnitude of combustion energy in one cylinder.

[0024] The temperature calculation unit 211 calculates the filter temperature Tgpf of the GPF 34. For example, the temperature calculation unit 211 can calculate the filter temperature Tgpf of the GPF 34 based on the rotation speed NE and the filling efficiency η.

[0025] When the amount of accumulated PM calculated by the accumulation amount calculation unit 210 becomes equal to or greater than a predetermined value, the regeneration process control unit 201 executes a regeneration process for reducing the amount of accumulated PM.

[0026] Furthermore, if the filter temperature Tgpf of the GPF 34 becomes lower than a specified temperature that is lower than a predetermined temperature after the torque reduction processing unit 203 executes the torque reduction processing, the regeneration processing control unit 201 resumes the regeneration processing for reducing the amount of PM accumulation.

[0027] When the filter temperature Tgpf of the GPF 34 calculated by the temperature calculation unit 211 becomes equal to or higher than a predetermined temperature during the regeneration process, the SOC expansion processing unit 202 interrupts the regeneration process and expands the upper limit of the SOC control range. In addition, the SOC expansion processing unit 202 increases the output torque of the engine 10 so that the battery 59 is charged until the SOC reaches the expanded upper limit.

[0028] When the SOC reaches the increased upper limit due to charging of the battery 59 by improving the output torque of the engine 10, the torque reduction processing unit 203 changes the engine operating point (combination of the rotation speed of the engine 10 and the torque of the engine 10) to one that allows partial cylinder fuel cut, and executes torque reduction processing to reduce the ratio of the torque of the internal combustion engine (engine 10) to the torque of the electric motors (first motor generator 52 and second motor generator 54). As a result, the torque reduction processing unit 203 controls the filter temperature Tgpf of the GPF 34 so that the filter temperature Tgpf of the GPF 34 decreases to below a specified temperature that is lower than a predetermined temperature.

[0029] (Procedure for controlling the regeneration process using ENGECU70) FIG. 3 is a flowchart showing a procedure for controlling the regeneration process by the ENGECU 70 provided in the vehicle 1 according to one embodiment.

[0030] First, the regeneration process control unit 201 of the ENGECU 70 determines whether or not to execute regeneration process with partial cylinder fuel cut (i.e., regeneration process for reducing the amount of PM deposited in the GPF 34) (step S301). For example, if the amount of PM deposited calculated by the deposition amount calculation unit 210 is equal to or greater than a predetermined value, the regeneration process control unit 201 determines to execute regeneration process with partial cylinder fuel cut, and if the amount of PM deposited calculated by the deposition amount calculation unit 210 is less than the predetermined value, the regeneration process control unit 201 determines not to execute regeneration process with partial cylinder fuel cut.

[0031] In step S301, if it is determined that partial cylinder fuel cut is not to be performed (step S301: NO), the regeneration processing control unit 201 of the ENGECU 70 stops the regeneration processing by partial cylinder fuel cut (step S308), and the ENGECU 70 ends the series of processing shown in Figure 3.

[0032] On the other hand, in step S301, if it is determined that regeneration processing using partial cylinder fuel cut is to be performed (step S301: YES), the SOC expansion processing unit 202 of the ENGECU 70 determines whether the filter temperature Tgpf of the GPF 34 calculated by the temperature calculation unit 211 is higher than a predetermined threshold value (step S302).

[0033] In step S302, if it is determined that the filter temperature Tgpf of the GPF 34 is higher than the predetermined threshold value (step S302: YES), the ENGECU 70 advances the process to step S303.

[0034] On the other hand, if it is determined in step S302 that the filter temperature Tgpf of the GPF 34 is not higher than the predetermined threshold value (step S302: NO), the ENGECU 70 advances the process to step S306.

[0035] <Step S303~> In step S303, the SOC expansion processing unit 202 of the ENGECU 70 expands the upper limit value of the SOC control range and increases the output torque of the engine 10 so that the battery 59 is charged until the SOC reaches the expanded upper limit value (step S303).

[0036] Next, the torque reduction processing unit 203 of the engine control unit 70 determines whether the SOC is higher than the increased upper limit (step S304).

[0037] In step S304, if it is determined that the SOC is not higher than the expanded upper limit (step S304: NO), the engine control unit 70 returns the process to step S303.

[0038] On the other hand, if it is determined in step S304 that the SOC is higher than the expanded upper limit (step S304: YES), the torque reduction processing unit 203 of the ENGECU 70 changes the engine operating point to one that allows partial cylinder fuel cut and reduces the ratio of the torque of the internal combustion engine (engine 10) to the torque of the electric motors (first motor generator 52 and second motor generator 54), thereby controlling the filter temperature Tgpf of the GPF 34 so that the filter temperature Tgpf of the GPF 34 decreases to below a specified temperature that is lower than the predetermined temperature (step S305). The ENGECU 70 then returns the process to step S302. In this case, in the next step S302, the SOC expansion processing unit 202 determines whether the filter temperature Tgpf of the GPF 34 calculated by the temperature calculation unit 211 is higher than the specified temperature.

[0039] <Step S306~> In step S306, the regeneration process control unit 201 of the engine control unit 70 executes regeneration process by partial cylinder fuel cut (step S306).

[0040] Next, the regeneration process control unit 201 of the ENGECU 70 determines whether the amount of accumulated PM calculated by the accumulation amount calculation unit 210 is less than a predetermined threshold value (step S307).

[0041] In step S307, if it is determined that the amount of accumulated PM is not less than the predetermined threshold value (step S307: NO), the ENGECU 70 returns the process to step S301.

[0042] On the other hand, if it is determined in step S307 that the amount of PM accumulation is less than the predetermined threshold (step S307: YES), the regeneration process control unit 201 of the ENGECU 70 stops the regeneration process by partial cylinder fuel cut (step S308), and the ENGECU 70 ends the series of processes shown in Figure 3.

[0043] As described above, in one embodiment, when the filter temperature Tgpf of the GPF 34 is higher than a predetermined threshold while performing regeneration processing using partial cylinder fuel cut, the ENGECU 70 can interrupt the regeneration processing, expand the upper limit value of the SOC control range, and charge the battery 59 by improving the output torque of the engine 10 so that the SOC becomes the expanded upper limit value.

[0044] In one embodiment, when the SOC reaches the expanded upper limit value, the ENGECU 70 changes the engine operating point to one that allows partial cylinder fuel cut and reduces the ratio of the torque of the internal combustion engine (engine 10) to the torque of the electric motor (first motor generator 52 and second motor generator 54), thereby controlling the filter temperature Tgpf of the GPF 34 so that the filter temperature Tgpf of the GPF 34 drops to below a specified temperature that is lower than a predetermined temperature.

[0045] Furthermore, the ENGECU 70 according to one embodiment can resume the regeneration process when the filter temperature Tgpf of the GPF 34 becomes lower than a specified temperature that is lower than a predetermined temperature.

[0046] Therefore, the ENGECU 70 according to one embodiment can efficiently lower the filter temperature Tgpf of the GPF 34, and therefore can efficiently perform a regeneration process that reduces the amount of PM deposited on the GPF 34.

[0047] In this case, the ENGECU 70 in one embodiment can charge the battery 59 so that the SOC reaches the expanded upper limit value, so that the torque deficiency caused by partial cylinder fuel cut can be compensated for by the electric motors (first motor generator 52 and second motor generator 54).

[0048] Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of the gist of the present invention described in the claims. [Explanation of symbols]

[0049] 1 vehicle 10 Engine (internal combustion engine) 34 GPF 52 First motor generator (electric motor) 54 Second motor generator (electric motor) 70 ENGECU (control unit) 100 MGECU 120 HVECU 201 Reproduction processing control unit 202 SOC expansion processing unit 203 Torque reduction processing unit 210 Deposition amount calculation section 211 Temperature calculation section

Claims

[Claim 1] A control device for a vehicle, a regeneration process control unit that executes a regeneration process to reduce the amount of particulate matter deposited on the filter when the amount of particulate matter deposited on the filter reaches or exceeds a predetermined value; an SOC expansion processing unit that interrupts the regeneration process and expands an upper limit of an SOC control range when the filter temperature becomes equal to or higher than a predetermined temperature during execution of the regeneration process; a torque reduction processing unit that executes a torque reduction process to reduce a ratio of the torque of the internal combustion engine to the torque of the electric motor when the SOC reaches the increased upper limit value; Equipped with The playback processing control unit The regeneration process is resumed when the filter temperature becomes lower than a specified temperature that is lower than the predetermined temperature after the torque reduction process is executed. Control device.

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