Drive control device

Abstract

To enhance the effect of suppressing variations in engine output torque when catalytic converter warm-up treatment is being performed. [Solution] The drive control device's processing circuit performs a catalyst warm-up process M21 that retards the ignition timing to a target time for warming up the catalyst, an inter-cylinder correction process M24 that adjusts the amount of fuel supplied to each cylinder in order to correct for variations in the magnitude of the engine's output torque, and a determination process M22 that determines whether the engine's operating state is stable when the ignition timing has reached the target time due to the catalyst warm-up process M21. The processing circuit executes the inter-cylinder correction process M24 on the condition that it has determined the operating state is stable while the catalyst warm-up process M21 is being executed.

Description

Technical Field

[0001] The present invention relates to a drive control device applied to a vehicle equipped with an engine.

Background Art

[0002] Patent Document 1 discloses a control device that controls the operation of an engine in which a catalyst for purifying exhaust gas is installed in an exhaust passage. The control device performs a catalyst warm-up process for warming up the catalyst by delaying the ignition timing, and during the execution of the catalyst warm-up process, in order to correct the variation in the engine speed within one cycle of the engine, a cylinder-to-cylinder correction process for correcting the fuel supply amount to each cylinder is executed. By executing such a cylinder-to-cylinder correction process, variation in the magnitude of the output torque of the engine at the ignition timing of a plurality of cylinders is suppressed.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the initial stage of the catalyst warm-up process, fluctuations in the engine speed and engine load factor occur due to the delay of the ignition timing. In such a situation, when the above-described cylinder-to-cylinder correction process is executed, it is difficult to say that the fuel supply amounts to a plurality of cylinders can be appropriately corrected.

Means for Solving the Problems

[0005] The drive control device for solving the above problems is applied to a vehicle equipped with a spark-ignition engine in which a catalyst is installed in the exhaust passage through which exhaust gases discharged from multiple cylinders flow. The drive control device includes a processing circuit that performs a catalyst warm-up process to retard the ignition timing to a target time for warming up the catalyst; an inter-cylinder correction process to adjust the amount of fuel supplied to each of the multiple cylinders in order to correct for variations in the magnitude of the engine's output torque at the ignition timing of the multiple cylinders; and a determination process that determines whether the operating state of the engine is stable when the ignition timing has reached the target time due to the catalyst warm-up process. The processing circuit performs the inter-cylinder correction process on the condition that it has determined that the operating state of the engine is stable during the execution of the catalyst warm-up process. [Effects of the Invention]

[0006] To enhance the effect of suppressing variations in engine output torque when catalytic converter warm-up treatment is being performed. [Brief explanation of the drawing]

[0007] [Figure 1] Figure 1 is a schematic diagram showing a vehicle equipped with one embodiment of a drive control device. [Figure 2] Figure 2 is a block diagram showing the various processes performed by the drive control device. [Figure 3] Figure 3 is a flowchart showing the series of processes executed by the first processing circuit when the determination process is executed. [Figure 4] Figure 4 is a flowchart showing a series of processes executed by the first processing circuit when inter-cylinder correction processing is performed. [Modes for carrying out the invention]

[0008] An embodiment of the drive control device will be described with reference to Figures 1 to 4. Figure 1 illustrates a hybrid vehicle 10 equipped with a drive control device 300. Hereafter, the hybrid vehicle 10 will be simply referred to as "vehicle 10".

[0009] Vehicle 10 further comprises a power plant 200 controlled by a drive control device 300, an operating mechanism 11, a plurality of axles 12, and a plurality of drive wheels 13. Torque output from the power plant 200 is transmitted to the plurality of axles 12 via the operating mechanism 11, causing the plurality of drive wheels 13 to rotate.

[0010] <Configuration of Powerplant 200> The power plant 200 comprises a spark-ignition engine 20, a damper 40, and a power transmission device 50.

[0011] The engine 20 comprises a crankshaft 21, multiple cylinders 22, an intake passage 23, and a throttle valve 24. A damper 40 is connected to the crankshaft 21. The throttle valve 24 adjusts the intake air volume, which is the flow rate of air that flows from the intake passage 23 towards the multiple cylinders 22.

[0012] In the multiple cylinders 22, a fuel-air mixture containing fuel injected from the fuel injector 25 and intake air is burned by the spark discharge of the spark plug 26. The combustion of the fuel-air mixture in the multiple cylinders 22 causes the pistons to reciprocate within the cylinders 22, which in turn causes the crankshaft 21 to rotate. The exhaust gas generated in the multiple cylinders 22 by the combustion of the fuel-air mixture is discharged into the exhaust passage 27. The exhaust passage 27 is equipped with a catalyst 28 that has the function of purifying the exhaust gas. An example of a catalyst 28 is a three-way catalyst.

[0013] The engine 20 is equipped with multiple sensors that output detection signals to the drive control device 300. These multiple sensors include a crank angle sensor 31, an air flow meter 32, and an air-fuel ratio sensor 33. The crank angle sensor 31 detects the rotation angle of the crankshaft 21 and outputs a detection signal corresponding to the rotation speed of the crankshaft 21. The air flow meter 32 detects the flow rate of air flowing through the intake passage 23. The air-fuel ratio sensor 33 detects the air-fuel ratio.

[0014] The power transmission device 50 includes an input shaft 51, a planetary gear mechanism 52, a first motor generator 53, a gear mechanism 54, and a second motor generator 55. The input shaft 51 is connected to the crankshaft 21 via a damper 40.

[0015] The planetary gear mechanism 52 includes a sun gear 52s, a ring gear 52r arranged coaxially with the sun gear 52s, a plurality of pinion gears 52p, and a planetary carrier 52c. The plurality of pinion gears 52p mesh with both the sun gear 52s and the ring gear 52r. The planetary carrier 52c supports the plurality of pinion gears 52p in a state that allows for both rotation and revolution.

[0016] The planetary carrier 52c is connected to the input shaft 51. In other words, the crankshaft 21 is connected to the planetary carrier 52c via the damper 40 and the input shaft 51. The sun gear 52s is connected to the first motor generator 53. The ring gear 52r is connected to the gear mechanism 54.

[0017] The first motor generator 53 includes a first rotor 53a and a first rotation angle sensor 53b. Since the first rotor 53a is connected to the sun gear 52s, the first rotor 53a rotates in sync with the input shaft 51. The first rotation angle sensor 53b detects the rotation angle of the first rotor 53a. The first rotation angle sensor 53b outputs a detection signal to the drive control device 300 corresponding to the rotation speed of the first rotor 53a.

[0018] The gear mechanism 54 has a counter drive gear 54a, a counter driven gear 54b, and a reduction gear 54c. The counter drive gear 54a rotates integrally with the ring gear 52r. The counter driven gear 54b is meshed with the counter drive gear 54a. The reduction gear 54c is meshed with the counter driven gear 54b. The reduction gear 54c is connected to the second motor generator 55.

[0019] The second motor generator 55 has a second rotor 55a and a second rotation angle sensor 55b. The second rotor 55a is connected to the reduction gear 54c. The second rotation angle sensor 55b detects the rotation angle of the second rotor 55a. The second rotation angle sensor 55b outputs a detection signal corresponding to the rotation speed of the second rotor 55a to the drive control device 300.

[0020] The power transmission device 50 includes a first inverter 61 which is an inverter for the first motor generator 53, and a second inverter 62 which is an inverter for the second motor generator 55.

[0021] The vehicle 10 further includes a final drive gear 71 that rotates integrally with the counter driven gear 54b, and a final driven gear 72 that is meshed with the final drive gear 71. The final driven gear 72 is connected to the operating mechanism 11.

[0022] <Drive control device 300> The drive control device 300 includes a first control device 310 and a second control device 320. The first control device 310 includes a first processing circuit 311 that controls the engine 20. The first processing circuit 311 has a CPU and a memory that stores a control program executed by the CPU. By the CPU executing the control program in the memory, the first processing circuit 311 controls the engine 20. Detection signals from the crank angle sensor 31, air flow meter 32, and air-fuel ratio sensor 33 provided in the engine 20 are input to the first control device 310.

[0023] The second control device 320 includes a second processing circuit 321 that controls the power transmission device 50. The second processing circuit 321 has a CPU and a memory that stores a control program executed by the CPU. The CPU executes the control program in the memory, thereby controlling the power transmission device 50. Detection signals from the first rotation angle sensor 53b and the second rotation angle sensor 55b of the power transmission device 50 are input to the second control device 320.

[0024] The drive control device 300 is equipped with a signal line 301 for transmitting the crank counter CNTcr acquired by the first control device 310 to the second control device 320. The crank counter CNTcr is a value that is counted up each time the rotation angle of the crankshaft 21 increases by a predetermined rotation angle. When one cycle of the engine 20 is completed, the crank counter CNTcr is reset to 0 (zero).

[0025] Signal line 301 is a dedicated signal line for transmitting the crank counter CNTcr from the first control device 310. Therefore, the delay when transmitting the crank counter CNTcr to the second control device 320 using signal line 301 is sufficiently suppressed to the extent that it does not affect the execution of various processes based on the crank counter CNTcr.

[0026] The drive control device 300 is equipped with a CAN communication line 302 for sending and receiving various types of information between the first control device 310 and the second control device 320. The CAN communication line 302 is used for sending and receiving information by numerous control devices mounted on the vehicle 10.

[0027] <Various processes executed by the drive control device 300> Referring to Figure 2, various processes performed by the drive control device 300 will be described. The drive control device 300 performs engine inertia torque calculation processing M11, first motor rotational angular velocity calculation processing M12, resonance effect torque calculation processing M13, and engine torque calculation processing M14. In addition, the drive control device 300 performs catalyst warm-up processing M21, determination processing M22, target injection amount calculation processing M23, and inter-cylinder correction processing M24.

[0028] The engine inertia torque calculation process M11 is performed by the first processing circuit 311 of the first control device 310. In the engine inertia torque calculation process M11, the first processing circuit 311 calculates the engine inertia torque Tei at predetermined intervals. The engine inertia torque Tei is the inertia torque of the engine 20. For example, the first processing circuit 311 calculates the engine inertia torque Tei as the product of the time derivative of the engine rotational angular velocity ωe and the moment of inertia of the engine 20.

[0029] The first motor rotational angular velocity calculation process M12 is performed by the second processing circuit 321 of the second control device 320. In the first motor rotational angular velocity calculation process M12, the second processing circuit 321 calculates the first motor rotational angular velocity ωmg1, which is the rotational angular velocity of the first rotor 53a of the first motor generator 53, at predetermined intervals. For example, the second processing circuit 321 can calculate the first motor rotational angular velocity ωmg1 by converting the first motor rotation speed Nmg1, which is the rotational speed of the first motor generator 53, into angular velocity.

[0030] The resonance-influenced torque calculation process M13 is performed by the second processing circuit 321. In the resonance-influenced torque calculation process M13, the second processing circuit 321 calculates the resonance-influenced torque Tdmp at predetermined intervals.

[0031] The output of the engine 20 is input to the input shaft 51 of the power transmission device 50 via the damper 40. When the output torque of the engine 20 fluctuates, torsional vibration occurs in the damper 40, and resonance caused by this torsional vibration may occur in the input shaft 51. When such resonance occurs in the input shaft 51, the torque caused by this resonance is input to the crankshaft 21. This torque caused by resonance in the power transmission device 50 is the resonance-influenced torque Tdmp.

[0032] In the resonance-affected torque calculation process M13, the second processing circuit 321 calculates the input shaft rotational angular velocity ωinp, which is the rotational angular velocity of the input shaft 51 of the power transmission device 50. The second processing circuit 321 can calculate the input shaft rotational angular velocity ωinp based on the first motor rotational speed Nmg1 and the second motor rotational speed Nmg2. The second motor rotational speed Nmg2 is the rotational speed of the second motor generator 55.

[0033] In the resonance-affected torque calculation process M13, the second processing circuit 321 calculates the resonance-affected torque Tdmp based on the input shaft rotational angular velocity ωinp, the first motor rotational angular velocity ωmg1, and the first motor torque Tmg1. The first motor torque Tmg1 is the output torque of the first motor generator 53.

[0034] An example of a method for calculating the input shaft rotational angular velocity ωinp and the resonance-influenced torque Tdmp is disclosed in "Japanese Patent Publication No. 2022-107264". The engine torque calculation process M14 is performed by the first processing circuit 311. In the engine torque calculation process M14, the first processing circuit 311 calculates the engine torque Te, which is the calculated value of the output torque of the engine 20, at predetermined intervals. The first processing circuit 311 calculates the engine torque Te as the sum of the engine inertia torque Tei and the resonance-influenced torque Tdmp. For example, the first processing circuit 311 calculates the engine torque Te as the sum of the engine inertia torque Tei, which is calculated at the same time as the first motor rotational angular velocity ωmg1 used to calculate the resonance-influenced torque Tdmp, and the said resonance-influenced torque Tdmp.

[0035] The catalyst warm-up treatment M21 is a process to warm up the catalyst 28 early. The first processing circuit 311 starts the catalyst warm-up treatment M21 when the temperature of the catalyst 28 is below a certain threshold. The threshold is the lower limit of the temperature range in which the catalyst 28 is activated, or a temperature slightly higher than that lower limit.

[0036] In the catalyst warm-up process M21, the first processing circuit 311 retards the ignition timing TMi compared to the reference ignition timing TMib. The reference ignition timing TMib is the ignition timing when the catalyst warm-up process M21 is not performed. For example, the first processing circuit 311 sets the most retarded timing as the target timing TMiTh, which is the target for the ignition timing TMi. The first processing circuit 311 gradually brings the ignition timing TMi closer to the target timing TMiTh. When the ignition timing TMi reaches the target timing TMiTh, the first processing circuit 311 holds the ignition timing TMi at the target timing TMiTh.

[0037] The determination process M22 is performed by the first processing circuit 311. In the determination process M22, the first processing circuit 311 determines whether the operating state of the engine 20 is stable when the ignition timing TMi has reached the target timing TMiTh due to the catalyst warm-up process M21. Details of the determination process M22 will be described later with reference to Figure 3.

[0038] The target injection amount calculation process M23 is performed by the first processing circuit 311. In the target injection amount calculation process M23, the first processing circuit 311 sets the target injection amount Qf, which is the target value of the fuel injection amount of the fuel injector 25. When the detected value of the air-fuel ratio sensor 33 is defined as the air-fuel ratio Af, and the target value of the air-fuel ratio Af is defined as the target air-fuel ratio AfTr, the first processing circuit 311 calculates the target injection amount Qf by feedback control that takes the deviation between the target air-fuel ratio AfTr and the air-fuel ratio Af as input.

[0039] The inter-cylinder correction process M24 is performed by the first processing circuit 311. In the inter-cylinder correction process M24, the first processing circuit 311 adjusts the amount of fuel supplied to each of the cylinders 22 in order to correct the variation in the magnitude of the engine torque Te at the ignition timing TMi of the multiple cylinders 22. Details of the inter-cylinder correction process M24 will be described later with reference to Figure 4.

[0040] <Decision Process M22> Referring to Figure 3, an example of the determination process M22 will be explained. In the determination process M22, the first processing circuit 311 repeatedly executes the series of processes shown in Figure 3 at predetermined intervals.

[0041] In step S11, the first processing circuit 311 determines whether or not the catalyst warm-up process M21 is currently being executed. If the catalyst warm-up process M21 is being executed (S11: YES), the first processing circuit 311 proceeds to step S13. On the other hand, if the catalyst warm-up process M21 is not being executed (S11: NO), the first processing circuit 311 proceeds to step S19.

[0042] In step S13, the first processing circuit 311 determines whether the ignition timing TMi has reached the target timing TMiTh. If the ignition timing TMi has reached the target timing TMiTh (S13: YES), the first processing circuit 311 proceeds to step S15. On the other hand, if the ignition timing TMi has not reached the target timing TMiTh (S13: NO), that is, if the ignition timing TMi is advanced beyond the target timing TMiTh, the first processing circuit 311 proceeds to step S19.

[0043] In step S15, the first processing circuit 311 determines whether the operating state of the engine 20 is stable. In this embodiment, the first processing circuit 311 determines that the operating state is stable if the duration of the following two conditions being met exceeds a predetermined determination duration. In this case, the first processing circuit 311 determines that the operating state is not stable if the duration has not reached the determination duration. The rotational speed fluctuation is a criterion for determining whether the fluctuation amount of the engine rotational speed NE is small or not. The load factor fluctuation is a criterion for determining whether the fluctuation amount of the engine load factor KL is small or not.

[0044] • The amount of fluctuation in engine speed NE is less than a specified amount of fluctuation in engine speed. • The amount of change in the engine load factor KL is less than the specified amount of change in the load factor. If the first processing circuit 311 determines that the operating state is stable (S15: YES), the first processing circuit 311 proceeds to step S17. On the other hand, if the first processing circuit 311 determines that the operating state is not stable (S15: NO), the first processing circuit 311 proceeds to step S19.

[0045] In step S17, the first processing circuit 311 sets the stability flag FLG to ON. The stability flag FLG is a flag that is set to ON when the operating state can be considered stable. Then, the first processing circuit 311 terminates the series of processes.

[0046] In step S19, the first processing circuit 311 sets the stability flag FLG to off. Then, the first processing circuit 311 terminates the series of processes. <Cylinder-to-cylinder correction processing M24> Referring to Figure 4, an example of the inter-cylinder correction process M24 will be explained. In the inter-cylinder correction process M24, the first processing circuit 311 repeatedly executes the series of processes shown in Figure 4 at predetermined intervals.

[0047] In step S31, the first processing circuit 311 sets cylinder number n to 1. In the following step S33, the first processing circuit 311 determines whether the engine torque Te(n) at the ignition timing TMi of the nth cylinder among the multiple cylinders 22 is substantially equal to the target engine torque TeTr. The target engine torque TeTr is the target value of the engine torque Te during the execution of the inter-cylinder correction process M24. For example, the average value of the engine torque Te at the ignition timing TMi of the multiple cylinders 22 is set as the target engine torque TeTr. If the difference between the engine torque Te(n) and the target engine torque TeTr falls within the acceptable range, the first processing circuit 311 determines that the engine torque Te(n) is substantially equal to the target engine torque TeTr (S33: YES). The first processing circuit 311 then proceeds to step S41. On the other hand, if the difference does not fall within the acceptable range, the first processing circuit 311 determines that the engine torque Te(n) is not substantially equal to the target engine torque TeTr (S33: NO). Then, the first processing circuit 311 moves the processing to step S35.

[0048] In step S35, the first processing circuit 311 determines whether the engine torque Te(n) at the ignition timing TMi of the nth cylinder is greater than the target engine torque TeTr. If the engine torque Te(n) is greater than the target engine torque TeTr (S35: YES), the first processing circuit 311 proceeds to step S37. On the other hand, if the engine torque Te(n) is less than or equal to the target engine torque TeTr (S35: NO), the first processing circuit 311 proceeds to step S39.

[0049] In step S37, the first processing circuit 311 reduces the nth correction amount CQ(n). The nth CQ(n) is the correction amount for the fuel supply to the nth cylinder. Here, the first processing circuit 311 may set a negative value as the nth correction amount CQ(n). Then, the first processing circuit 311 proceeds to step S41.

[0050] In step S39, the first processing circuit 311 increases the nth correction amount CQ(n). Here, the first processing circuit 311 may set a positive value as the nth correction amount CQ(n). Then, the first processing circuit 311 proceeds to step S41.

[0051] In step S41, the first processing circuit 311 sets the sum of the target injection amount Qf calculated in the target injection amount calculation process M23 and the nth correction amount CQ(n) as the target injection amount QfTr(n) for the fuel injector 25 for the nth cylinder. Then, the first processing circuit 311 moves the process to step S43.

[0052] In step S43, the first processing circuit 311 updates the cylinder number n so that it increases by one. In the following step S45, the first processing circuit 311 determines whether the cylinder number n is greater than the number of cylinders nTh. The number of cylinders nTh for the engine 20 shown in Figure 1 is 4. If the cylinder number n is less than or equal to the number of cylinders nTh (S45: NO), the first processing circuit 311 proceeds to step S33. On the other hand, if the cylinder number n is greater than the number of cylinders nTh (S45: YES), the first processing circuit 311 terminates the series of processes.

[0053] <Operation and Effects of This Embodiment> (1) When the catalyst warm-up process M21 is started, the ignition timing TMi is retarded from the reference ignition timing TMib. When the ignition timing TMi is retarded, the engine speed NE and engine load ratio KL are changed in accordance with the change in ignition timing TMi. Because the target injection amount Qf is calculated by feedback control, the engine speed NE and engine load ratio KL are not stable even immediately after the ignition timing TMi reaches the target timing TMiTh during the execution of the catalyst warm-up process M21. When the engine speed NE and engine load ratio KL are not stable, the output of the engine 20 tends to fluctuate. However, after a certain amount of time has passed, the engine speed NE and engine load ratio KL will stabilize. As a result, the fluctuations in the output of the engine 20 caused by fluctuations in engine speed NE and engine load ratio KL will subside.

[0054] In the drive control device 300, the first processing circuit 311 executes the inter-cylinder correction process M24 on the condition that it has determined that the operating state of the engine 20 is stable while the catalyst warm-up process M21 is being executed. In other words, the first processing circuit 311 can start the inter-cylinder correction process M24 after the variation in the output of the engine 20 caused by variations in engine speed NE and engine load ratio KL has subsided. As a result, the first processing circuit 311 can effectively suppress variations in the output torque of the engine 20 when the catalyst warm-up process M21 is being executed.

[0055] (2) The first processing circuit 311 can calculate the engine torque Te by adding the synchronized engine inertia torque Tei and the resonance-influenced torque Tdmp. The first processing circuit 311 uses this engine torque Te to perform the inter-cylinder correction process M24. As a result, the first processing circuit 311 can accurately adjust the amount of fuel supplied to multiple cylinders 22 in the inter-cylinder correction process M24.

[0056] <Example of changes> The above embodiment can be implemented with the following modifications. The above embodiment and the following modifications can be combined with each other to the extent that they do not contradict each other technically.

[0057] The first processing circuit 311 may, in the determination process M22, determine whether or not the operating state of the engine 20 is stable using a method different from the method described in the above embodiment, if it is possible to determine whether or not the operating state of the engine 20 is stable. The length of time from the moment the ignition timing TMi reaches the target timing TMiTh due to the execution of the catalyst warm-up process M21 until the operating state of the engine 20 actually stabilizes can be estimated from experiments or simulations. Therefore, the first processing circuit 311 may determine in the determination process M22 that the operating state of the engine 20 is stable if the elapsed time from the moment the ignition timing TMi reaches the target timing TMiTh exceeds a predetermined determination elapsed time. In this case, the first processing circuit 311 determines that the operating state is not stable if the elapsed time is less than or equal to the determination elapsed time.

[0058] The first processing circuit 311 may interrupt the inter-cylinder correction process M24 if the operating state of the engine 20 becomes unstable while it is executing the inter-cylinder correction process M24. Then, when the first processing circuit 311 determines that the operating state has stabilized, it may resume the inter-cylinder correction process M24.

[0059] The powerplant controlled by the drive control device may have a different configuration from the powerplant 200 shown in Figure 1, as long as it includes an engine 20. For example, the powerplant may be one applied to a serial hybrid system or one applied to a parallel hybrid system. Alternatively, the powerplant may include an engine 20 but not a motor generator. The drive control device can then calculate the engine torque Te using a method appropriate to the configuration of the powerplant.

[0060] The drive control device only needs to have at least one processing circuit. The first processing circuit 311 and the second processing circuit 321 are not limited to those that include a CPU and ROM and execute software processing. That is, the first processing circuit 311 and the second processing circuit 321 may have any of the following configurations: (a), (b), and (c).

[0061] (a) The first processing circuit 311 and the second processing circuit 321 each include one or more processors that perform various processes according to a computer program. The processors include a CPU and memory such as RAM and ROM. The memory stores program code or instructions configured to cause the CPU to perform the processes. The memory, i.e., computer-readable media, includes any available media that can be accessed by a general-purpose or dedicated computer.

[0062] (b) The first processing circuit 311 and the second processing circuit 321 are each equipped with one or more dedicated hardware circuits that perform various processes. Examples of dedicated hardware circuits include application-specific integrated circuits, i.e., ASICs or FPGAs. ASIC is an abbreviation for "Application Specific Integrated Circuit," and FPGA is an abbreviation for "Field Programmable Gate Array."

[0063] (c) The first processing circuit 311 and the second processing circuit 321 each include one or more processors that execute a portion of the various processes according to a computer program, and one or more dedicated hardware circuits that execute the remaining processes of the various processes. [Explanation of Symbols]

[0064] 10...Vehicle, 20...Engine, 21...Crankshaft, 22...Cylinder, 27...Exhaust passage, 28...Catalytic converter, 40...Damper, 50...Power transmission device, 53...First motor generator, 53a...First rotor, 300...Drive control device, 311,312...Processing circuit.

Claims

1. This applies to vehicles equipped with a spark-ignition engine in which a catalytic converter is installed in the exhaust passage through which exhaust gases discharged from multiple cylinders flow. A catalyst warm-up treatment is performed to retard the ignition timing to a target time for warming up the catalyst, In order to correct the variation in the magnitude of the engine's output torque at the ignition timing of the aforementioned multiple cylinders, an inter-cylinder correction process is performed to adjust the amount of fuel supplied to each of the aforementioned multiple cylinders, The system includes a processing circuit that performs a determination process to determine whether the engine's operating state is stable when the ignition timing has reached the target timing due to the catalyst warm-up process, The processing circuit executes the inter-cylinder correction process on the condition that it has determined that the engine's operating state is stable during the execution of the catalyst warm-up process. Drive control device.

2. The processing circuit determines in the determination process that the engine's operating state is stable if the duration of the state in which the amount of fluctuation in engine speed is less than a predetermined amount of fluctuation in engine speed and the amount of fluctuation in engine load ratio is less than a predetermined amount of fluctuation in load ratio exceeds a predetermined determination duration. The drive control device according to claim 1.

3. The processing circuit determines, in the determination process, that the engine's operating state is stable when the elapsed time from the point in time when the ignition timing reaches the target time exceeds a predetermined determination elapsed time. The drive control device according to claim 1.

4. The vehicle comprises a damper connected to the crankshaft of the engine, and a power transmission device connected to the crankshaft via the damper. The power transmission device has a motor generator having a rotor that rotates in sync with the crankshaft, The processing circuit is configured to perform a calculation process to calculate the engine torque, which is the calculated value of the engine's output torque. The inter-cylinder correction process is a process that adjusts the amount of fuel supplied to each of the multiple cylinders in order to correct the variation in the magnitude of the engine torque at the ignition timing of the multiple cylinders. The aforementioned calculation process is, The motor rotational angular velocity, which is the rotational angular velocity of the rotor, The resonance-influenced torque, which is the torque caused by resonance generated in the power transmission device, is calculated based on the motor rotational angular velocity. Based on the rotational angular velocity of the crankshaft, the engine inertia torque, which is the inertia torque of the engine, is calculated. This includes calculating the engine torque as the sum of the engine inertia torque, which is calculated at the same time as the motor rotational angular velocity used to calculate the resonance-affected torque, and the resonance-affected torque. A drive control device according to any one of claims 1 to 3.

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