Hybrid vehicle control device

Abstract

The present invention provides a control device for a hybrid vehicle. The ENG-ECU executes a specific-cylinder fuel-cut process for stopping combustion of a mixture in some of a plurality of cylinders of an internal combustion engine, and a transmission process for transmitting internal combustion engine operating information related to the execution of the specific-cylinder fuel-cut process to the HV-ECU. The HV-ECU executes a torque compensation process for compensating for a decrease in internal combustion engine torque caused by the execution of the specific-cylinder fuel-cut process using the output torque of a second MG based on the received internal combustion engine operating information. The ENG-ECU executes a process for starting the specific-cylinder fuel-cut process in a combustion cycle after a standby time, including the time until the HV-ECU receives the internal combustion engine operating information, has elapsed since the execution of the transmission process.

Description

Technical Field

[0001] The present invention relates to a control device for a hybrid vehicle. Background Art

[0002] The hybrid vehicle disclosed in Japanese Patent Application Laid-Open No. 2009-248698 is equipped with an internal combustion engine having multiple cylinders and an electric motor as prime movers. Furthermore, the hybrid vehicle includes an internal combustion engine control device for controlling the internal combustion engine, an electric motor control device for controlling the electric motor, and an integrated control device for comprehensively controlling the internal combustion engine and the electric motor. Furthermore, in this hybrid vehicle, the electric motor performs torque compensation to suppress torque shock caused by fuel cuts in the internal combustion engine. Summary of the Invention

[0003] Fuel cutoff of the internal combustion engine and torque compensation by the electric motor are executed by separate control units. Therefore, information is transmitted between the control units through mutual communication. However, there is a delay in this mutual communication, so torque compensation by the electric motor may not be able to keep up with the timing of fuel cutoff.

[0004] A hybrid vehicle control device that solves the above-mentioned problem is applied to a hybrid vehicle equipped with an internal combustion engine having multiple cylinders and an electric motor as prime movers. The control device includes a first control device and a second control device. The first control device performs a specific-cylinder fuel cutoff process to stop combustion of a mixture in some of the multiple cylinders and transmits engine operating information related to the execution of the specific-cylinder fuel cutoff process to the second control device. The second control device performs a torque compensation process based on the received engine operating information to control the electric motor so as to compensate for at least a portion of the decrease in engine torque caused by the execution of the specific-cylinder fuel cutoff process using the output torque of the electric motor. The first control device also performs a process to initiate the specific-cylinder fuel cutoff process in a combustion cycle that has elapsed a predetermined waiting time since the execution of the transmitting process, where the waiting time includes the time from the first control device transmitting the engine operating information to the second control device until the second control device receives the engine operating information.

[0005] According to this configuration, the standby time includes the time from when the first control unit transmits engine operating information to the second control unit until the second control unit receives the engine operating information. Furthermore, the specific-cylinder fuel cutoff process is initiated in a combustion cycle that occurs after the standby time has elapsed from the execution of the aforementioned transmission process. By initiating the specific-cylinder fuel cutoff process in consideration of communication delays between the first and second control units, it is possible to prevent torque compensation by the electric motor from catching up with the combustion cessation of the air-fuel mixture caused by the specific-cylinder fuel cutoff process.

[0006] In addition, in the above-mentioned control device, it may be that the second control device includes a calculation process for calculating a compensation torque for compensating at least a portion of the decrease in the internal combustion engine torque as the torque compensation process, and when the time from the first control device sending the internal combustion engine operation information to the second control device to the second control device receiving the internal combustion engine operation information is set as the first time, and the time required for executing the calculation process is set as the second time, the standby time includes the first time and the second time.

[0007] In this configuration, the standby time also includes the time required to calculate the compensation torque by the torque compensation process. Therefore, in addition to taking into account the communication delay between the first and second control devices, the time required to calculate the compensation torque is also taken into account when initiating the specific-cylinder fuel cutoff process. This further prevents the torque compensation performed by the electric motor from catching up with the combustion cessation of the air-fuel mixture performed by the specific-cylinder fuel cutoff process.

[0008] In addition, in the above-mentioned control device, it may be that the control device includes a third control device that controls the electric motor by receiving a control signal from the second control device, and the second control device performs a sending process of sending information related to the compensation torque calculated in the calculation process as the control signal to the third control device. When the time from the second control device sending the information related to the compensation torque to the third control device to the time the third control device receives the information related to the compensation torque is set as the third time, the standby time includes the first time, the second time and the third time.

[0009] In this configuration, the standby time also includes the time from when the second control unit transmits information regarding the compensation torque to the third control unit until the third control unit receives the information. Therefore, the specific-cylinder fuel cutoff process is initiated while also taking into account communication delays between the second and third control units. This further prevents the torque compensation performed by the electric motor from catching up with the combustion cessation of the air-fuel mixture performed by the specific-cylinder fuel cutoff process. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, in which like reference numerals represent like elements, and in which:

[0011] Figure 1 This is a schematic diagram of the configuration of a hybrid vehicle and a control device in one embodiment.

[0012] Figure 2 This is a flowchart showing the processing steps executed by the ENG-ECU of this embodiment.

[0013] Figure 3 This is a flowchart showing the processing steps executed by the HV-ECU of this embodiment.

[0014] Figure 4 It is a timing chart showing the operation of this embodiment. DETAILED DESCRIPTION

[0015] Hereinafter, an embodiment of a control device for a hybrid vehicle will be described with reference to the drawings.

[0016] <General Structure of Vehicle>

[0017] like Figure 1 As shown, the hybrid vehicle (hereinafter referred to as vehicle) 500 has an internal combustion engine 10, a first electric generator (hereinafter referred to as first MG) 71 as an electric motor, a second electric generator (hereinafter referred to as second MG) 72 also as an electric motor, a first converter 75, a second converter 76 and a battery 77.

[0018] Internal combustion engine 10, first MG 71, and second MG 72 serve as the driving source for vehicle 500. Details of internal combustion engine 10 will be described later. First MG 71 is a generator motor that functions as both a motor and a generator. Second MG 72, like first MG 71, is a generator motor. First MG 71 is electrically connected to battery 77 via first inverter 75. Second MG 72 is electrically connected to battery 77 via second inverter 76. First inverter 75 and second inverter 76 perform DC to AC power conversion. Battery 77 supplies power to first MG 71 and second MG 72 or stores the power supplied by them.

[0019] Vehicle 500 includes a power split mechanism 40, a reduction gear 50, a speed reduction mechanism 60, a differential 61, and drive wheels 62. Crankshaft 14, which serves as the output shaft of internal combustion engine 10, and the rotational shaft of first MG 71 are coupled to power split mechanism 40. Furthermore, the rotational shaft of second MG 72 is coupled to power split mechanism 40 via speed reduction gear 50. Power split mechanism 40 is coupled to drive wheels 62 via speed reduction mechanism 60 and differential 61.

[0020] The power distribution mechanism 40 is a planetary gear mechanism. The power distribution mechanism 40 includes a sun gear 41, a ring gear 42, a plurality of pinion gears 43, and a planetary carrier 44. The sun gear 41 is an externally toothed gear. The sun gear 41 rotates on its own axis. The ring gear 42 is an internally toothed gear. The ring gear 42 rotates coaxially with the sun gear 41. A plurality of pinion gears 43 are interposed between the sun gear 41 and the ring gear 42. Each pinion gear 43 meshes with both the sun gear 41 and the ring gear 42. Each pinion gear 43 is capable of orbiting around the sun gear 41. Specifically, each pinion gear 43 is supported by the planetary carrier 44 in a state capable of rotating on its own axis and orbiting around the sun gear 41. The planetary carrier 44 rotates coaxially with the sun gear 41 as the pinion gears 43 orbit. The sun gear 41 is connected to the rotation axis of the first MG 71. The planetary carrier 44 is connected to the crankshaft 14. The ring gear shaft 45 , which is an output shaft of the ring gear 42 , is connected to both the reduction gear 50 and the speed reduction mechanism 60 .

[0021] The reduction gear 50 is a planetary gear mechanism. The reduction gear 50 includes a sun gear 51, a ring gear 52, and a plurality of pinion gears 53. The sun gear 51 is an externally toothed gear. The sun gear 51 rotates on its own axis. The ring gear 52 is an internally toothed gear. The ring gear 52 rotates coaxially with the sun gear 51. The plurality of pinion gears 53 are interposed between the sun gear 51 and the ring gear 52. Each pinion gear 53 meshes with both the sun gear 51 and the ring gear 52. Each pinion gear 53 is supported in a state in which it can rotate on its own axis but cannot revolve around the sun gear 51. The sun gear 51 is connected to the rotation axis of the second MG 72. The ring gear 52 is connected to the aforementioned ring gear shaft 45.

[0022] When the crankshaft 14 of the internal combustion engine 10 inputs torque to the planetary carrier 44 of the power split mechanism 40, the power split mechanism 40 distributes the torque to the sun gear 41 and the ring gear 42. The torque distributed to the sun gear 41 is input to the rotation shaft of the first MG 71. When the rotation shaft of the first MG 71 rotates due to this torque, the first MG 71 can function as a generator.

[0023] On the other hand, when the first MG 71 functions as an electric motor, the rotating shaft of the first MG 71 inputs torque to the sun gear 41 of the power distribution mechanism 40. In this case, the power distribution mechanism 40 distributes the input torque to the planetary carrier 44 and the ring gear 42. The torque input to the planetary carrier 44 is input to the crankshaft 14. This torque rotates the crankshaft 14. In this way, the first MG 71 can impart torque to the crankshaft 14.

[0024] Furthermore, the torque of the internal combustion engine 10 or the torque of the first MG 71 distributed to the ring gear 42 is input to the drive wheels 62 via the ring gear shaft 45, the reduction gear mechanism 60, and the differential 61. At this time, the reduction gear mechanism 60 amplifies the input torque and outputs it. Furthermore, the differential 61 allows a difference in rotational speed to occur between the left and right drive wheels 62.

[0025] Furthermore, when vehicle 500 is decelerated, second MG 72 is caused to function as a generator, thereby generating a regenerative braking force in vehicle 500 corresponding to the amount of power generated by second MG 72. On the other hand, when second MG 72 is caused to function as a motor, the torque of second MG 72 is input to drive wheels 62 via reduction gear 50, ring gear shaft 45, reduction mechanism 60, and differential 61.

[0026] The vehicle 500 includes various sensors such as a first rotation angle sensor 86 , a second rotation angle sensor 87 , an accelerator sensor 83 , and a vehicle speed sensor 85 .

[0027] First rotational angle sensor 86 is located near the rotation axis of first MG 71. First rotational angle sensor 86 detects rotational position Sm1 of the rotation axis of first MG 71. Second rotational angle sensor 87 is located near the rotation axis of second MG 72. Second rotational angle sensor 87 detects rotational position Sm2 of the rotation axis of second MG 72. Accelerator sensor 83 detects accelerator operation amount ACP, which is the amount of accelerator pedal operation in vehicle 500. Vehicle speed sensor 85 is located near drive wheels 62. Vehicle speed sensor 85 detects vehicle speed SP, which is the traveling speed of vehicle 500.

[0028] <General Structure of Internal Combustion Engine>

[0029] like Figure 1 As shown, the internal combustion engine 10 includes the aforementioned crankshaft 14 , a crank angle sensor 18 , a water temperature sensor 82 , and the like.

[0030] The internal combustion engine 10 is a four-cylinder inline engine. Below, the cylinders 11 of the internal combustion engine 10 are indicated in their order of arrangement with cylinder numbers such as 1st cylinder #1, 2nd cylinder #2, 3rd cylinder #3, and 4th cylinder #4. Each cylinder 11 houses a piston. The piston can reciprocate within each cylinder 11. The piston within each cylinder 11 is connected to a crankshaft 14 via a connecting rod. The crankshaft 14 rotates in accordance with the reciprocating motion of the piston within each cylinder 11. A crank angle sensor 18 is located near the crankshaft 14. The crank angle sensor 18 outputs a signal Scr indicating the rotational position of the crankshaft 14.

[0031] The internal combustion engine 10 also includes a water jacket 19. The water jacket 19 is a passage through which cooling water for cooling the internal combustion engine 10 flows. The water temperature sensor 82 detects the temperature of the cooling water in the water jacket 19, that is, the cooling water temperature THW.

[0032] Internal combustion engine 10 has four spark plugs 16. Each spark plug 16 is installed in each cylinder 11. The tip of each spark plug 16 is exposed within each cylinder 11. Each spark plug 16 ignites the mixture of intake air and fuel within cylinder 11 through spark discharge. During a single combustion cycle of internal combustion engine 10, the mixture ignites in the order of first cylinder #1, third cylinder #3, fourth cylinder #4, and second cylinder #2.

[0033] The internal combustion engine 10 includes an intake passage 15, an air flow meter 81, and a fuel injection valve 17. The intake passage 15 is a passage that introduces intake air into each cylinder 11. The intake passage 15 is connected to each cylinder 11. The air flow meter 81 is provided midway in the intake passage 15. The air flow meter 81 detects the flow rate of air flowing through the intake passage 15, i.e., the intake air amount GA. The fuel injection valve 17 is provided for each cylinder 11 to supply fuel into the cylinder 11.

[0034] The internal combustion engine 10 includes an exhaust passage 21, a three-way catalyst 22, and a gasoline particulate filter (hereinafter referred to as a GPF) 23. The exhaust passage 21 is a passage through which exhaust gas discharged from each cylinder 11 flows. The exhaust passage 21 is connected to each cylinder 11. The three-way catalyst 22 is located midway in the exhaust passage 21. The three-way catalyst 22 has oxygen storage capacity and purifies the exhaust gas. The GPF 23 is located downstream of the three-way catalyst 22 in the exhaust passage 21. The GPF 23 collects particulate matter (hereinafter referred to as PM) contained in the exhaust gas.

[0035] <General Structure of Control Device>

[0036] Vehicle 500 includes HV-ECU 100, ENG-ECU 200, and MG-ECU 300 as control devices. HV-ECU 100 constitutes the second control device. ENG-ECU 200 constitutes the first control device. MG-ECU 300 constitutes the third control device.

[0037] HV-ECU 100 and ENG-ECU 200 perform bidirectional communication via a communication line. HV-ECU 100 and MG-ECU 300 also perform bidirectional communication via a communication line.

[0038] HV-ECU 100 includes CPU 110 , ROM 120 , and the like, and various controls are implemented by CPU 110 executing programs stored in ROM 120 .

[0039] <About HV-ECU>

[0040] The HV-ECU 100 comprehensively controls the vehicle 500. The HV-ECU 100 obtains the accelerator operation amount ACP and the vehicle speed SP. Furthermore, based on the accelerator operation amount ACP and the vehicle speed SP, the HV-ECU 100 calculates the target internal combustion engine speed NE* (the target value of the rotational speed of the crankshaft 14), and the target internal combustion engine torque Te* (the target value of the output torque of the internal combustion engine 10). Furthermore, based on the accelerator operation amount ACP and the vehicle speed SP, the HV-ECU 100 calculates the target first torque Tm1* (the target value of the torque of the first MG 71), and the target second torque Tm2* (the target value of the torque of the second MG 72).

[0041] ENG-ECU 200 includes a CPU 210 , a ROM 220 , and the like, and various controls are implemented by CPU 210 executing programs stored in ROM 220 .

[0042] <About ENG-ECU>

[0043] ENG-ECU 200 obtains target engine speed NE* and target engine torque Te* calculated by HV-ECU 100 , and controls the output of internal combustion engine 10 based on these target engine speed NE* and target engine torque Te*.

[0044] To understand the operating state of the internal combustion engine 10, the ENG-ECU 200 obtains information such as the signal Scr from the crank angle sensor 18, the cooling water temperature THW, and the intake air amount GA. Based on the signal Scr, the ENG-ECU 200 calculates the engine speed NE. Furthermore, the ENG-ECU 200 calculates the engine load factor KL based on the engine speed NE and the intake air amount GA. The engine load factor KL is a parameter that determines the amount of air filling the combustion chamber of the cylinder 11 and is the ratio of the inflow air amount per cylinder per combustion cycle to a reference inflow air amount. The reference inflow air amount is variably set according to the engine speed NE.

[0045] ENG-ECU 200 also calculates the accumulation amount DPM of PM trapped by GPF 23 based on engine speed NE, engine load factor KL, and cooling water temperature THW. When accumulation amount DPM exceeds a predetermined value, ENG-ECU 200 executes a cylinder-specific fuel cutoff process (hereinafter referred to as cylinder-specific FC process) as a regeneration process to regenerate GPF 23. This cylinder-specific FC process discharges oxygen and unburned fuel into exhaust passage 21, thereby increasing the temperature of GPF 23 and burning and removing PM trapped by GPF 23. Specifically, by discharging oxygen and unburned fuel into exhaust passage 21, the unburned fuel is burned in three-way catalyst 22 and other devices, raising the temperature of the exhaust gas. This increase in exhaust temperature causes the temperature of GPF 23 to rise. Furthermore, by supplying oxygen to the hot GPF 23, PM trapped by GPF 23 is burned and removed.

[0046] ENG-ECU 200 repeatedly performs, as specific cylinder FC processing, a process of stopping combustion of the air-fuel mixture in one of the four cylinders in one combustion cycle and performing combustion of the air-fuel mixture in the remaining three cylinders in a plurality of consecutive combustion cycles.

[0047] ENG-ECU 200 executes fuel cutoff, which stops fuel injection in cylinders where combustion of the air-fuel mixture has been stopped. Hereinafter, cylinders where combustion has been stopped are referred to as FC cylinders. Oxygen is discharged from these FC cylinders into exhaust passage 21. Furthermore, ENG-ECU 200 appropriately changes the cylinder designated as the FC cylinder so that the cylinder where combustion of the air-fuel mixture has been stopped is not biased towards a specific cylinder.

[0048] Meanwhile, ENG-ECU 200 injects fuel into the combustion cylinder, which is a cylinder that burns the air-fuel mixture, so that the air-fuel ratio of the air-fuel mixture in the cylinder becomes richer than the stoichiometric air-fuel ratio. Unburned fuel is discharged from the combustion cylinder into exhaust passage 21 .

[0049] <About MG-ECU>

[0050] The MG-ECU 300 acquires the target first torque Tm1* and the target second torque Tm2* calculated by the HV-ECU 100, and controls the first MG 71 and the second MG 72 based on these target first torque Tm1* and target second torque Tm2*.

[0051] The MG-ECU 300 controls the first MG 71 by controlling the first converter 75. In addition, the MG-ECU 300 controls the second MG 72 by controlling the second converter 76.

[0052] The MG-ECU 300 controls the first MG 71 and the second MG 72 while grasping their states. The MG-ECU 300 acquires the rotational position Sm1 of the rotational shaft of the first MG 71 and the rotational position Sm2 of the rotational shaft of the second MG 72 as parameters required for grasping the states of the first MG 71 and the second MG 72.

[0053] <Regarding torque compensation>

[0054] During the execution of the above-mentioned specific cylinder FC process, the internal combustion engine torque generated by the combustion of the air-fuel mixture cannot be obtained in the FC cylinder. Therefore, torque compensation processing is performed to compensate for such a decrease in the internal combustion engine torque.

[0055] To execute this torque compensation processing, the HV-ECU 100 adds a compensation torque Th2, which is the internal combustion engine torque corresponding to one cylinder of the internal combustion engine 10, to the target second torque Tm2* of the second MG 72. And the MG-ECU 300 performs torque compensation by controlling the first converter 75 based on the target second torque Tm2* obtained by adding the compensation torque Th2 during the expansion stroke of the FC cylinder.

[0056] Hereinafter, the processing steps executed by each ECU to execute the processing related to such torque compensation will be described.

[0057] Figure 2 shows the processing steps executed by the ENG-ECU 200. In addition, Figure 3 shows the processing steps executed by the HV-ECU 100. In addition, each of the above-mentioned processing steps is repeatedly executed at each predetermined cycle.

[0058] <Processing of ENG-ECU>

[0059] As Figure 2 shown, the ENG-ECU 200 first determines whether there is a requirement to execute the specific cylinder FC process (S100). And when there is no execution requirement (S100: No), the ENG-ECU 200 temporarily ends this processing.

[0060] On the other hand, if there is a request to execute the specific cylinder FC process (S100: YES), ENG-ECU 200 calculates a torque achievement ratio TAR (S110). Torque achievement ratio TAR is a value indicating the ratio of the internal combustion engine torque value during execution of the specific cylinder FC process to the internal combustion engine torque value during one combustion cycle when the specific cylinder FC process is not executed.

[0061] For example, the value of the internal combustion engine torque in one combustion cycle when the FC process for a specific cylinder is not executed is set to "1." Furthermore, when the number of cylinders in the internal combustion engine is set to k, the number of FC cylinders in one combustion cycle is set to n, and the rate of increase in the internal combustion engine torque due to enrichment of the air-fuel ratio in the combustion cylinder is set to α%, the value is expressed by the following equation (1).

[0062] TAR=(1 / k)×(k-n)×(1+α / 100)…(1)

[0063] For example, in the case of a 4-cylinder engine, when n=1 and α=5%, TAR=(1 / 4)×(4−1)×(1+5 / 100)=0.788.

[0064] Next, ENG-ECU 200 executes a first transmission process (S120) of engine operating information related to the execution of the specific cylinder FC process to HV-ECU 100. The engine operating information related to the execution of the specific cylinder FC process includes the torque achievement ratio TAR calculated in S100 and the cylinder number of the cylinder that serves as the FC cylinder in this specific cylinder FC process.

[0065] Next, ENG-ECU 200 calculates a combustion cycle for starting the FC process for the specific cylinder based on engine speed NE and waiting time TW ( S130 ). hereinafter, the combustion cycle for starting the FC process for the specific cylinder is referred to as an FC start cycle.

[0066] The standby time TW is the sum of a first time Tw1, a second time Tw2 (described later), and a third time Tw3 (described later) required from the transmission of the engine operating information in S120 to the receipt of the engine operating information by the HV-ECU 100. This time corresponds to the time required to implement the aforementioned torque compensation. Furthermore, the standby time TW is a fixed value determined by the communication circuit connecting the ECUs and the specifications of the CPU performing various calculations. The ENG-ECU 200 calculates the first combustion cycle after the standby time TW, starting from the time the engine operating information was transmitted in S120, as the FC start cycle.

[0067] Next, the ENG-ECU 200 determines whether it is the start cycle of FC (S140). And, when it is not the start cycle of FC (S140: No), the ENG-ECU 200 repeats the process of S140.

[0068] On the other hand, when it is determined that it is the start cycle of FC (S140: Yes), the ENG-ECU 200 executes the specific cylinder FC process (S150) and temporarily ends this process.

[0069] <Process of HV-ECU>

[0070] As Figure 3 shown, the HV-ECU 100 first receives the internal combustion engine operation information transmitted in the process of S120 above (S200).

[0071] Next, the HV-ECU 100 calculates the above-mentioned compensation torque Th2 and re-sets the target second torque Tm2* (S210). In this S210, based on the cylinder number of the FC cylinder included in the received internal combustion engine operation information, the cylinder number that requires torque compensation is grasped. In addition, the value obtained by dividing the target internal combustion engine torque Te* by the number of cylinders k and multiplying it by the reduction ratio G from the second MG 72 to the drive wheel 62 is calculated as the compensation torque Th2. And, by adding the compensation torque Th2 to the current target second torque Tm2, the re-setting of the target second torque Tm2 corresponding to the FC cylinder is performed. The sum of the calculation process of this S210, that is, the calculation of the compensation torque Th2 and the process time required for the re-setting of the target second torque Tm2* becomes the above-mentioned second time Tw2.

[0072] Next, the HV-ECU 100 executes the second transmission process (S220) of transmitting the re-set target second torque Tm2* to the MG-ECU 300.

[0073] The process of this S220 is a transmission process of transmitting information related to the compensation torque Th2 calculated in the calculation process of S210, more specifically, the target second torque Tm2* re-set using this compensation torque Th2 as a control signal to the MG-ECU 300. And, the time required from when the target second torque Tm2* is transmitted in this S220 until the MG-ECU 300 receives it is the above-mentioned third time Tw3. The MG-ECU 300 that receives the target second torque Tm2* transmitted in S220 controls the second converter 76 in such a way that the output torque of the second MG 72 becomes the received re-set target second torque Tm2* during the expansion stroke of the FC cylinder in which combustion is stopped by the execution of the specific cylinder FC process.

[0074] Next, the HV-ECU 100 resets the target internal combustion engine torque Te* by multiplying the torque achievement ratio TAR included in the received internal combustion engine operating information by the current target internal combustion engine torque Te* ( S230 ). The HV-ECU 100 then transmits the reset target internal combustion engine torque Te* to the ENG-ECU 200 ( S240 ), temporarily terminating this process.

[0075] The ENG-ECU 200, which has received the reset target engine torque Te*, controls the internal combustion engine 10 in such a manner as to obtain the reset target engine torque Te*. In this way, by resetting the target engine torque Te* of the internal combustion engine 10, it is possible to suppress the deviation (deviation, deviation) between the actual engine torque during the execution of the specific cylinder FC process and the target engine torque Te*. Therefore, for example, it is possible to suppress the situation in which the engine torque of the internal combustion engine 10 increases based on the deviation between the actual engine torque and the target engine torque Te* despite the torque compensation performed by the second MG 72. In addition, it is also possible to suppress the occurrence of erroneous abnormality judgments caused by such torque deviations.

[0076] <Function of Implementation Method>

[0077] Figure 4 An example of the execution method of torque compensation when executing the specific cylinder FC process is shown in FIG. Figure 4 In the example shown, the third cylinder #3 is an FC cylinder.

[0078] like Figure 4 As shown, when a request to execute the specific cylinder FC process is generated at time t1 , the internal combustion engine operation information is transmitted from the ENG-ECU 200 to the HV-ECU 100 at time t2 .

[0079] The first combustion cycle after the waiting time TW has elapsed from time t2 is calculated as the FC start cycle. Therefore, in the combustion cycle immediately following the request to execute the specific cylinder FC process, fuel cutoff is not performed in the third cylinder #3 at time t3, and the air-fuel mixture is combusted in the third cylinder #3. Therefore, torque compensation by the second MG 72 is not performed at time t3.

[0080] On the other hand, in this example, since the combustion cycle immediately following the request to execute the specific cylinder FC process is the FC start cycle, fuel cutoff of the third cylinder #3 is executed in the subsequent combustion cycles including the FC start cycle (times t4 and t5). Furthermore, at times t4 and t5, torque compensation is performed by the second MG 72 to compensate for the decrease in engine torque caused by the fuel cutoff of the third cylinder #3.

[0081] <Effects of Implementation>

[0082] (1) The aforementioned standby time TW includes a first time Tw1, which is the time from when ENG-ECU 200 transmits engine operating information to HV-ECU 100 until HV-ECU 100 receives the engine operating information. Furthermore, the specific-cylinder FC process begins in a combustion cycle that occurs after the aforementioned first transmission process has elapsed from the standby time TW. By initiating the specific-cylinder FC process in consideration of communication delays between ENG-ECU 200 and HV-ECU 100, it is possible to prevent torque compensation by second MG 72 from catching up with combustion cessation of the air-fuel mixture performed by the specific-cylinder FC process.

[0083] (2) Furthermore, the aforementioned standby time TW also includes the time required to calculate the compensation torque Th2 by the torque compensation process and to reset the target second torque Tm2* based on the compensation torque Th2, i.e., the second time Tw2. Therefore, in addition to considering the communication delay between ENG-ECU 200 and HV-ECU 100, the time required for calculating the compensation torque Th2 is also considered when starting the specific cylinder FC process. This further prevents the torque compensation performed by second MG 72 from catching up with the combustion stop of the air-fuel mixture performed by the specific cylinder FC process.

[0084] (3) Furthermore, the aforementioned standby time TW also includes a third time Tw3, which is the time from when HV-ECU 100 transmits information regarding the compensation torque to MG-ECU 300 until MG-ECU 300 receives the information. Therefore, the specific cylinder FC process is initiated taking into account the communication delay between HV-ECU 100 and MG-ECU 300. This further prevents the torque compensation performed by second MG 72 from catching up with the combustion stop of the air-fuel mixture performed by the specific cylinder FC process.

[0085] <Change Example>

[0086] This embodiment can be implemented by modifying as follows: This embodiment and the following modifications can be implemented in combination with each other within a range that does not technically conflict.

[0087] For example, when the compensation torque Th2 is a fixed value and there is no need to calculate the compensation torque Th2 by the torque compensation process, the second time Tw2 may be excluded from the waiting time TW.

[0088] HV-ECU 100 may also have the function of MG-ECU 300. In this case, since there is no need to separately prepare MG-ECU 300, third time Tw3 may be excluded from standby time TW.

[0089] The process of executing the FC treatment for a specific cylinder is not limited to the regeneration process described above. For example, the FC treatment for a specific cylinder may be executed for catalyst warm-up or sulfur poisoning recovery. Furthermore, for example, when the oxygen storage amount of the three-way catalyst 22 is below a predetermined value, a control process may be executed to stop combustion of the air-fuel mixture in only some cylinders and to control combustion of the air-fuel mixture in the remaining cylinders to the stoichiometric air-fuel ratio.

[0090] The number of cylinders whose combustion is stopped during execution of the above-described specific cylinder FC process can be appropriately changed with "the number of cylinders - 1" as a maximum value. Alternatively, the number of cylinders whose combustion is stopped may be fixed to a predetermined number of cylinders.

[0091] In the above-described torque compensation process, a portion of the decrease in internal combustion engine torque caused by execution of the specific cylinder FC process may be compensated by the output torque of second MG 72 .

[0092] The information related to the FC cylinder in the internal combustion engine operation information is not limited to the cylinder number of the FC cylinder, but may be other information, such as a crank angle for specifying the FC cylinder.

[0093] The GPF 23 is not limited to the one provided downstream of the three-way catalyst 22 in the exhaust passage 21. Alternatively, the three-way catalyst 22 may be replaced with an oxidation catalyst that oxidizes components contained in the exhaust gas.

[0094] Each control device is not limited to a control device that includes a CPU and a ROM and executes software processing. For example, a dedicated hardware circuit such as an ASIC that performs hardware processing on at least a portion of the software processing in the above-mentioned embodiment may also be provided. That is, the control device may be any one of the following (a) to (c). (a) A processing device that executes all of the above-mentioned processing according to a program, and a program storage device such as a ROM that stores the program. (b) A processing device and a program storage device that execute a portion of the above-mentioned processing according to a program, and a dedicated hardware circuit that executes the remaining processing. (c) A dedicated hardware circuit that executes all of the above-mentioned processing. Here, there may be multiple software execution devices and dedicated hardware circuits equipped with a processing device and a program storage device.

[0095] The configuration of the internal combustion engine 10 is not limited to the example of the above embodiment. For example, the number of cylinders 11 may be changed. It is sufficient that there are a plurality of cylinders 11.

[0096] The vehicle is not limited to a series-parallel hybrid vehicle, and may be, for example, a parallel hybrid vehicle or a series hybrid vehicle.

Claims

1. A control device for a hybrid vehicle, the control device being applied to a hybrid vehicle equipped with an internal combustion engine having multiple cylinders and an electric motor as prime movers, The control device includes a first control device and a second control device, The first control device executes a specific cylinder fuel cut process for stopping combustion of an air-fuel mixture in a portion of the plurality of cylinders and a transmission process for transmitting engine operation information related to execution of the specific cylinder fuel cut process to the second control device. The second control device performs a torque compensation process for controlling the electric motor based on the received internal combustion engine operating information so as to compensate at least a portion of a decrease in the internal combustion engine torque caused by execution of the fuel cut process for the specific cylinder using the output torque of the electric motor during the expansion stroke of the part of the cylinders. The first control device executes a process of starting the specific cylinder fuel cut process in a combustion cycle after a predetermined waiting time has elapsed since the execution of the transmission process, and The waiting time includes a time from when the first control device transmits the internal combustion engine operating information to the second control device until the second control device receives the internal combustion engine operating information.

2. The hybrid vehicle control device according to claim 1, The second control device includes, as the torque compensation processing, a calculation process for calculating a compensation torque for compensating for at least a portion of a decrease in the internal combustion engine torque. When the time from when the first control device sends the internal combustion engine operating information to the second control device to when the second control device receives the internal combustion engine operating information is set as the first time, and the time required to execute the calculation processing is set as the second time, the standby time includes the first time and the second time.

3. The hybrid vehicle control device according to claim 2, The control device includes a third control device that receives a control signal from the second control device and controls the electric motor. The second control device performs a transmission process of transmitting information on the compensation torque calculated in the calculation process to the third control device as the control signal. When the time from when the second control device transmits the information on the compensation torque to the third control device to when the third control device receives the information on the compensation torque is defined as a third time, the waiting time includes the first time, the second time, and the third time.

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