Hybrid vehicle control device

Abstract

To suppress vehicle vibration.SOLUTION: A crank shaft of an internal combustion engine having a plurality of cylinders is connected with a revolving shaft of a rotation electrical machine. A controller 70 performs: stop processing which stops a part of cylinders of the internal combustion engine; calculating processing of estimated torque of the internal combustion engine in which annealing-process is performed using annealing time constant; adjusting processing of torque outputted from the rotation electrical machine according to the estimated torque; and setting processing of the annealing time constant in which larger value is set for the annealing time constant during execution of the stop processing relative to non-execution of the stop processing.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[0002] Patent Document 1 describes a hybrid vehicle equipped with an internal combustion engine and an electric motor as power sources. In this hybrid vehicle, torque control of the electric motor is performed according to a calculated estimated torque of the internal combustion engine. Here, in this hybrid vehicle, an smoothing process using an smoothing time constant is performed when calculating the estimated torque. Furthermore, the smoothing time constant is set to a different value between the supercharging region and the non-supercharging region. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-152250 Summary of the Invention [Problem to be solved by the invention]

[0004] In a hybrid vehicle, a stop process may be performed to stop combustion in some of the cylinders of the internal combustion engine. When the stop process is performed, the engine torque of the cylinders where combustion has stopped decreases, causing the engine torque output from the internal combustion engine to oscillate. As a result, such an oscillating component is reflected in the estimated torque of the internal combustion engine, causing the estimated torque to oscillate as well. When the estimated torque oscillates, the torque of the electric motor, which is adjusted according to the estimated torque, also oscillates, which may increase vehicle vibration. [Means for solving the problem]

[0005] A control device for a hybrid vehicle that solves the above-mentioned problems is applied to a hybrid vehicle in which a rotating shaft of a rotating electric machine is connected to the crankshaft of an internal combustion engine having multiple cylinders. This control device executes a stop process that stops combustion in some cylinders of the internal combustion engine, a process that calculates an estimated torque of the internal combustion engine that has been smoothed using an smoothing time constant, a process that adjusts the torque output from the rotating electric machine in accordance with the estimated torque, and a process that sets the smoothing time constant to a larger value during the stop process than when the stop process is not being executed.

[0006] According to this configuration, when the stop process is executed, the smoothing time constant used to calculate the estimated torque is increased. Therefore, vibrations in the estimated torque during the stop process are suppressed. Therefore, vibrations in the torque of the rotating electrical machine, which is adjusted according to the estimated torque, are also suppressed, thereby suppressing vehicle vibrations. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a diagram showing the configuration of a drive system and a control device for a vehicle according to an embodiment; [Figure 2] 4 is a flowchart showing a procedure of a process executed by the control device according to the embodiment. [Figure 3] 4 is a flowchart showing a procedure of a process executed by the control device according to the embodiment. [Figure 4] 4 is a flowchart showing a procedure of a process executed by the control device according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, a specific embodiment of a control device for a hybrid vehicle will be described. <Vehicle drivetrain and control device configuration> As shown in FIG. 1, an internal combustion engine 10 mounted on a vehicle VC includes, for example, four cylinders #1 to #4.

[0009] A throttle valve 14 is provided in an intake passage 12 of the internal combustion engine 10. An intake port 12a, which is a downstream portion of the intake passage 12, is provided with a port injection valve 16 that injects fuel into the intake port 12a.

[0010] When an intake valve 18 opens, air drawn into the intake passage 12 and fuel injected from the port injection valve 16 flow into a combustion chamber 20. Fuel is injected into the combustion chamber 20 from an in-cylinder injection valve 22. The air-fuel mixture in the combustion chamber 20 is combusted in response to a spark discharge from an ignition device 24. The combustion energy generated at this time is converted into rotational energy of a crankshaft 26.

[0011] The air-fuel mixture burned in the combustion chamber 20 is discharged as exhaust gas into an exhaust passage 30 when an exhaust valve 28 opens. A three-way catalyst 32 having oxygen storage capacity and a gasoline particulate filter (GPF 34) are provided in the exhaust passage 30. 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, which is a rotating electric machine, is mechanically connected to a sun gear S of the planetary gear mechanism 50. Furthermore, a rotating shaft 54a of a second motor generator 54, which is also a rotating electric machine, and drive wheels 60 are mechanically connected to a ring gear R of the planetary gear mechanism 50. A hydraulic transmission 100 is provided on a power transmission path between the rotating shaft 54a of the second motor generator 54 and the drive wheels 60.

[0013] An AC voltage is applied to the terminals of the first motor generator 52 by a first inverter 56. Furthermore, an AC voltage is applied to the terminals of the second motor generator 54 by a second inverter 58. Both the first inverter 56 and the second inverter 58 are power conversion circuits that convert the terminal voltage of a battery 59, which serves as a DC voltage source, into an AC voltage and output the AC voltage.

[0014] The control device 70 operates operating parts of the internal combustion engine 10, such as the throttle valve 14, the port injection valve 16, the in-cylinder injection valve 22, and the ignition device 24, in order to control the control variables of the internal combustion engine 10, such as torque and exhaust component ratio.

[0015] The control device 70 also operates the first inverter 56 to control the torque, which is the control variable of the first motor generator 52, which is the control object. The control device 70 also operates the second inverter 58 to control the torque, which is the control variable of the second motor generator 54, which is the control object. The control device 70 also operates the hydraulic mechanism of the transmission 100 to control the gear ratio of the transmission 100, which is the control object.

[0016] 1 shows operation signals MS1 to MS7 for the throttle valve 14, the port injection valve 16, the in-cylinder injection valve 22, the ignition device 24, the first inverter 56, the second inverter 58, and the transmission 100, respectively.

[0017] The control device 70 references the intake air amount Ga detected by the air flow meter 80 and the output signal Scr of the crank angle sensor 82 to control the controlled variable of the internal combustion engine 10. The control device 70 also references the water temperature THW detected by the water temperature sensor 84 and the output signal Sp of the output side rotation angle sensor 86 that detects the rotation angle of the ring gear R. The control device 70 also references the temperature Tb of the battery 59 detected by the temperature sensor 87, the charge / discharge current I of the battery 59 detected by the current sensor 88, and the terminal voltage Vb of the battery 59 detected by the voltage sensor 89. The control device 70 also references the output signal Sm1 of the first rotation angle sensor 90 that detects the rotation angle of the first motor-generator 52 to control the controlled variable of the first motor-generator 52. The control device 70 calculates a first rotation speed Nmg1, which is the rotation speed of the rotary shaft 52a of the first motor-generator 52, based on the output signal Sm1. Furthermore, in order to control the control amount of the second motor-generator 54, the control device 70 refers to the output signal Sm2 of the second rotation angle sensor 92 that detects the rotation angle of the second motor-generator 54. The control device 70 calculates a second rotation speed Nmg2 that is the rotation speed of the rotary shaft 54a of the second motor-generator 54 based on the output signal Sm2. The control device 70 also refers to the accelerator operation amount ACCP that is the amount of depression of the accelerator pedal detected by the accelerator sensor 94.

[0018] The control device 70 includes a CPU 72, a ROM 74, a peripheral circuit 76, and a communication line 78. The CPU 72, the ROM 74, and the peripheral circuit 76 are capable of communicating with each other via the communication line 78. The peripheral circuit 76 includes a circuit that generates a clock signal that regulates internal operations, a power supply circuit, a reset circuit, and the like. The control device 70 controls the control variables by the CPU 72 executing a program stored in the ROM 74.

[0019] Among the processes executed by the control system shown in FIG. 1, the regeneration process of the GPF 34, the process related to the operation of the motor generator and the internal combustion engine, and the process for prohibiting the regeneration process will be described below.

[0020] <GPF playback process> Figure 2 shows the procedure of the playback process. The process shown in Figure 2 is realized by the CPU 72 repeatedly executing the program stored in the ROM 74, for example, at a predetermined cycle. In the following, the step numbers of each process are represented by numbers with "S" added at the beginning.

[0021] In the series of processes shown in Figure 2, the CPU 72 first acquires the engine rotation speed NE, the filling efficiency η, and the water temperature THW (S10). The engine rotation speed NE is calculated by the CPU 72 based on the output signal Scr. The filling efficiency η is calculated by the CPU 72 based on the engine rotation speed NE and the intake air amount Ga.

[0022] Next, the CPU 72 calculates the update amount ΔDPM of the deposition amount DPM based on the engine rotation speed NE, the filling efficiency η, and the water temperature THW (S12). Here, the deposition amount DPM is the amount of PM collected by the GPF 34. Specifically, the CPU 72 calculates the amount of PM in the exhaust gas discharged to the exhaust passage 30 based on the engine rotation speed NE, the filling efficiency η, and the water temperature THW. Also, the CPU 7 determines the temperature of the GPF 34 based on the engine rotation speed NE and the filling efficiency η. Then the CPU 72 calculates the update amount ΔDPM based on the amount of PM in the exhaust gas and the temperature of the GPF 34. When executing the process of S20 described later, the temperature of the GPF 34 and the update amount ΔDPM may be calculated based on the increment coefficient K.

[0023] Next, the CPU 72 updates the deposition amount DPM according to the update amount ΔDPM (S14). Next, the CPU 72 determines whether the execution flag Fc is "1" or not (S16). The execution flag Fc indicates that the regeneration process for burning and removing the PM of the GPF 34 is being executed when it is "1", and indicates otherwise when it is "0".

[0024] When the CPU 72 determines that the execution flag Fc is "0" (S16: NO), it determines whether the accumulation amount DPM is equal to or greater than the regeneration execution value DPMH (S18). The regeneration execution value DPMH is set to a value at which the amount of PM trapped by the GPF 34 is large and it is desirable to remove the PM.

[0025] When the CPU 72 determines that the accumulation amount DPM is equal to or greater than the regeneration execution value DPMH (S18: YES), it executes the regeneration process and sets the execution flag Fc to "1" (S20).

[0026] As the regeneration process according to this embodiment, the CPU 72 executes a stop process to stop combustion in some cylinders of the internal combustion engine 10 by stopping fuel injection from the port injection valve 16 and the in-cylinder injection valve 22 of cylinder #1. In addition, in conjunction with the execution of this stop process, a process is executed to make the air-fuel ratio of the mixture in the combustion chamber 20 of cylinders #2, #3, and #4 richer than the stoichiometric air-fuel ratio. These processes are, first, processes for raising the temperature of the three-way catalyst 32. That is, by discharging oxygen and unburned fuel into the exhaust passage 30, the unburned fuel is oxidized in the three-way catalyst 32, thereby raising the temperature of the three-way catalyst 32. Second, these processes are processes for raising the temperature of the GPF 34 and supplying oxygen to the heated GPF 34 to oxidize and remove PM trapped by the GPF 34. That is, when the temperature of the three-way catalyst 32 becomes high, the temperature of the GPF 34 rises due to the flow of high-temperature exhaust gas into the GPF 34. Then, oxygen flows into the GPF 34 at a high temperature, and the PM trapped by the GPF 34 is oxidized and removed.

[0027] Specifically, the CPU 72 assigns "0" to the required injection amount Qd for the port injection valve 16 and the in-cylinder injection valve 22 of cylinder #1. Meanwhile, the CPU 72 assigns a value obtained by multiplying the base injection amount Qb by the increase coefficient K to the required injection amount Qd for cylinders #2, #3, and #4. The base injection amount Qb is the injection amount for making the air-fuel ratio of the mixture the stoichiometric air-fuel ratio. The CPU 72 calculates the base injection amount Qb by multiplying the charging efficiency η by a predetermined coefficient.

[0028] The CPU 72 sets the increase coefficient K so that the amount of unburned fuel in the exhaust gas discharged from cylinders #2, #3, and #4 into the exhaust passage 30 is equal to or less than the amount that causes the unburned fuel in the exhaust to react just right with the oxygen discharged from cylinder #1. Specifically, in the early stage of the regeneration process of the GPF 34, the CPU 72 sets the air-fuel ratio of the mixture in cylinders #2, #3, and #4 to a value that is as close as possible to the amount that causes the unburned fuel to react just right, in order to quickly raise the temperature of the three-way catalyst 32.

[0029] On the other hand, when the CPU 72 determines in the process of S16 that the execution flag Fc is "1" (S16: YES), it determines whether the accumulation amount DPM is equal to or less than the stop threshold value DPML (S22). The stop threshold value DPML is set to a value at which the amount of PM trapped in the GPF 34 becomes small enough to allow the regeneration process to be stopped.

[0030] When the CPU 72 determines that the accumulation amount DPM is greater than the stop threshold value DPML (S22: NO), the CPU 72 continues the process of S20, that is, the regeneration process. On the other hand, when it is determined that the accumulation amount DPM is equal to or less than the stop threshold value DPML (S22: YES), the CPU 72 stops the process of S20 and sets the execution flag Fc to "0" (S28).

[0031] It should be noted that when the CPU 72 has completed the process of S20 or S28, or when a negative determination is made in the process of S18, the CPU 72 temporarily ends the series of processes shown in FIG. <Processing related to the operation of the motor generator and internal combustion engine> The procedure of the process relating to the operation of the motor generator and the internal combustion engine is shown in Fig. 3. The process shown in Fig. 3 is realized by the CPU 72 repeatedly executing a program stored in the ROM 74, for example, at a predetermined interval.

[0032] In the series of processes shown in Fig. 3, the CPU 72 first acquires the accelerator operation amount ACCP and the output side rotation speed Np (S40). The output side rotation speed Np is the rotation speed of the ring gear R. In other words, it is a variable indicating the vehicle speed. The output side rotation speed Np is calculated by the CPU 72 based on the output signal Sp.

[0033] The CPU 72 calculates a required drive torque Tp*, which is the torque required for the drive wheels 60, based on the accelerator operation amount ACCP and the output side rotation speed Np (S42). Next, the CPU 72 substitutes the product of the required drive torque Tp* and the output side rotation speed Np into the traveling power Pp* (S44).

[0034] Next, the CPU 72 calculates the required charge / discharge power Pbatt* of the battery 59 based on the charging rate SOC of the battery 59 (S46). The required charge / discharge power Pbatt* is positive when discharging. More specifically, when the charging rate SOC is equal to or lower than a predetermined value, the CPU 72 sets the required charge / discharge power Pbatt* to negative so as to charge the battery 59. The charging rate SOC is calculated by the CPU 72 based on the charging / discharging current I and the terminal voltage Vb.

[0035] Next, the CPU 72 subtracts the product of the required charge / discharge power Pbatt* and the conversion efficiency Kef from the running power Pp*, and assigns the result to the required engine power Pe* (S48). Next, the CPU 72 calculates the target engine rotation speed NE* and the required engine torque Te* (S50).

[0036] The target engine speed NE* is a target value of the engine speed NE. The CPU 72 first calculates a target engine speed NE* that allows the internal combustion engine 10 to operate efficiently, for example, based on the required engine power Pe*. This can be achieved by having the CPU 72 perform map calculations to determine the target engine speed NE* while map data is pre-stored in the ROM 74. The map data is data that uses the required engine power Pe* as an input variable and the target engine speed NE* as an output variable. The map data is a set of data that includes discrete values ​​of the input variables and values ​​of the output variables corresponding to each of the input variable values. The map calculation may be a process in which, when the value of an input variable matches any of the input variable values ​​in the map data, the value of the output variable in the corresponding map data is used as the calculation result. The map calculation may be a process in which, when the value of an input variable does not match any of the input variable values ​​in the map data, the value obtained by interpolating the values ​​of multiple output variables included in the map data is used as the calculation result.

[0037] Then, the CPU 72 divides the required engine output Pe* by the target engine rotation speed NE* and assigns the result to the required engine torque Te*. The CPU 72 controls the opening of the throttle valve 14 so that the torque of the internal combustion engine 10 becomes the required engine torque Te*.

[0038] Next, the CPU 72 calculates a target first rotation speed Nmg1* (S52). The target first rotation speed Nmg1* is a target value of the first rotation speed Nmg1, which is the rotation speed of the rotary shaft 52a of the first motor generator 52. More specifically, the target first rotation speed Nmg1* is the first rotation speed Nmg1 when the engine rotation speed NE becomes the target engine rotation speed NE*. The CPU 72 calculates the target first rotation speed Nmg1* based on the target engine rotation speed NE* and the output side rotation speed Np using the following equation (1).

[0039] Nmg1*=[{1 / (1+ρ)}·Np-NE*] / {ρ / (1+ρ)}…(1) However, the planetary gear ratio ρ in the above formula is the value obtained by dividing the number of teeth of the sun gear S by the number of teeth of the ring gear R.

[0040] Next, the CPU 72 calculates a required first torque Tmg1* (S54). The required first torque Tmg1* is a torque required for the first motor generator 52. More specifically, the required first torque Tmg1* is a torque of the first motor generator 52 that is required to make the first rotation speed Nmg1 equal to the target first rotation speed Nmg1*.

[0041] The CPU 72 determines the required first torque Tmg1* as the sum of an open-loop term and a feedback term. Here, the open-loop term is a value obtained by "{-ρ / (1+ρ)} Te*." Note that "-ρ / (1+ρ)" is a coefficient that converts the torque of the carrier C into the torque of the sun gear S. On the other hand, the feedback term is a manipulated variable for feedback control of the first rotational speed Nmg1. The feedback term is the sum of the output value of the proportional element and the output value of the integral element. The output value of the proportional element is a value obtained by subtracting the first rotational speed Nmg1 from the target first rotational speed Nmg1* to obtain an error err1, and multiplying this error err1 by a proportional gain Kp. The output value of the integral element is the integrated value of the error err1 multiplied by an integral gain Ki. The CPU 72 controls the driving of the first motor-generator 52 so as to obtain the required first torque Tmg1*.

[0042] Next, the CPU 72 calculates the required second torque base value Tmg2b* (S56). This required second torque base value Tmg2b* is calculated as follows. First, the CPU 72 multiplies "1 / (1+ρ)" by the estimated torque Tee and assigns the result to the direct torque Ted. Here, "1 / (1+ρ)" is a coefficient for converting the torque of the carrier C into the torque of the ring gear R.

[0043] The estimated torque Tee is an estimated value of the torque output by the internal combustion engine 10, and is calculated by the CPU 72 at predetermined intervals in a process separate from this process. The estimated torque Tee is a value obtained by smoothing the estimated torque base value Teeb calculated by the following equation (2) using an smoothing time constant N. In this smoothing process, the larger the value of the smoothing time constant N, the smaller the amount of change in the estimated torque Tee relative to the amount of change in the estimated torque base value Teeb. In other words, the larger the value of the smoothing time constant N, the gentler the responsiveness of the estimated torque Tee to changes in the estimated torque base value Teeb. The smoothing time constant N is variably set in the process shown in FIG. 4, which will be described later.

[0044]

number

[0045] Next, the CPU 72 determines whether the execution flag Fc of the reproduction process is "1" (S58). When it is determined that the execution flag Fc is "1" (S58: YES), the CPU 72 calculates the second superimposed torque ΔTmg2* (S38). The second superimposed torque ΔTmg2* is a torque for suppressing rotation fluctuations of the crankshaft 26 that accompany the regeneration process. The CPU 72 variably sets the second superimposed torque ΔTmg2* based on the engine rotation speed NE, the required engine torque Te*, and the second rotation speed Nmg2. The objects that are variably set here are the phase, magnitude, and waveform of the second superimposed torque ΔTmg2*.

[0046] Next, the CPU 72 assigns a value obtained by adding the second superimposed torque ΔTmg2* to the required second torque base value Tmg2b* to the required second torque Tmg2* (S62). Then, the CPU 72 controls the drive of the second motor generator 54 so as to obtain the required second torque Tmg2*. The processes of S58, S60, and S62 are compensation processes in which, when the stop process is executed, the second motor generator 54 generates torque to compensate for fluctuations in the rotation of the crankshaft 26 due to a decrease in torque of the internal combustion engine 10 caused by the cessation of combustion in some cylinders.

[0047] When it is determined in the process of S58 that the execution flag Fc is not "1" (S58: YNO), the CPU 72 assigns the required second torque base value Tmg2b* to the required second torque Tmg2* (S64). Then, the CPU 72 controls the drive of the second motor generator 54 so as to obtain the required second torque Tmg2*.

[0048] When the CPU 72 completes the processing of S62 or S64, it temporarily ends the series of processing steps shown in FIG. <Setting the smoothing time constant> When the stop process is executed by executing the regeneration process, the engine torque output from the internal combustion engine 10 begins to oscillate at a high frequency. Here, each value used to calculate the estimated torque base value Teeb contains an error. Furthermore, communication delays occur between the sensor and the control device 70, making it difficult to accurately estimate the engine torque that oscillates at a high frequency.

[0049] Furthermore, if the engine torque fluctuates at a high frequency, the estimated engine torque also fluctuates at a high frequency. When the estimated engine torque fluctuates at a high frequency, the required second torque Tmg2* calculated based on the estimated engine torque also becomes a high-frequency command value. However, it is difficult from a hardware perspective to actually output torque corresponding to such a high-frequency command value from the second motor-generator 54.

[0050] For these reasons, when the stop process is being executed, it becomes difficult to ensure an accurate driving force corresponding to the engine torque, which vibrates at high frequency, and there is a risk that vehicle vibrations will occur. Therefore, in this embodiment, the above-mentioned smoothing time constant N is appropriately set to suppress the vibration of the estimated torque Tee, thereby suppressing the occurrence of vehicle vibration.

[0051] Fig. 4 shows the procedure for setting the smoothing time constant N. The process shown in Fig. 4 is realized by the CPU 72 repeatedly executing a program stored in the ROM 74 at predetermined intervals.

[0052] In the series of processes shown in FIG. 4, the CPU 72 first determines whether the regeneration process execution flag Fc is "1" (S100). When it is determined that the execution flag Fc is "1" (S100: YES), the CPU 72 assigns a second constant N2 to the smoothing time constant N (S120). In this embodiment, a first constant N1 and a second constant N2 are set in advance as values ​​to be assigned to the smoothing time constant N. A value greater than the first constant N1 is set to the second constant N2. When it is determined that the execution flag Fc is "1" in this way, that is, when the stop process is being executed, the smoothing time constant N is set to the value of the second constant N2, which is greater than the first constant N1. As a result, even when the torque of the internal combustion engine 10 oscillates at a high frequency, the change in the estimated torque Tee is gradual, and fluctuations are suppressed.

[0053] If it is determined in the process of S100 that the execution flag Fc is not "1" (S100: YNO), the CPU 72 determines whether or not the current state is a transient state in which the torque of the internal combustion engine 10 is changing significantly (S110). In the process of S100, the CPU 72 determines that the current state is a transient state when, for example, any one of the following conditions (A) to (C) is satisfied.

[0054] Condition (A): The vehicle is accelerating or decelerating. Condition (B): A predetermined time has elapsed since the fuel cut process was initiated for the internal combustion engine 10. The fuel cut process is a process for stopping fuel injection in all cylinders of the internal combustion engine 10 when a predetermined condition is met.

[0055] Condition (C): A predetermined time has elapsed since the start of the fuel cut recovery process. The fuel cut recovery process is a process in which, when a predetermined condition is met, the fuel cut process is stopped and fuel injection is resumed in all cylinders of the internal combustion engine 10.

[0056] When it is determined in the process of S110 that the engine is in a transient state (S110: YES), the CPU 72 assigns the first constant N1 to the smoothing time constant N (S130). When it is determined that the engine is in a transient state, the smoothing time constant N is set to the first constant N1, which is smaller than the second constant N2, thereby improving the responsiveness of the estimated torque Tee when the torque of the internal combustion engine 10 changes significantly.

[0057] On the other hand, if it is determined in the process of S110 that the current state is not a transient state (S110: NO), the CPU 72 assigns the second constant N2 to the smoothing time constant N (S140). Then, when the CPU 72 has completed any one of the processes of S120, S130, and S140, it temporarily ends this process.

[0058] <Action and effect> The operation and effects of this embodiment will be described. When the above-described stop processing is executed, the smoothing time constant N used when calculating the estimated torque Tee is set to a large value through the processing of S100 and S120 shown in FIG. 4. Therefore, fluctuations in the estimated torque Tee during execution of the stop processing are suppressed, and vibrations in the estimated torque Tee are suppressed. As a result, vibrations in the required second torque base value Tmg2b* calculated in accordance with the estimated torque Tee are suppressed. Therefore, vibrations in the torque of the second motor-generator 54, which is adjusted in accordance with the estimated torque Tee, are suppressed, thereby suppressing vehicle vibrations.

[0059] <Example of change> This embodiment can be modified as follows: This embodiment and the following modifications can be combined and implemented within the scope of technical compatibility.

[0060] In the process of S120 and the process of S140 shown in FIG. 4, the value substituted for the smoothing time constant N is the same, the second constant N2. Alternatively, the value substituted for the smoothing time constant N in the process of S120 and the process of S140 may be different. For example, the value substituted for the smoothing time constant N in the process of S120 may be a value larger than the second constant N2. Also, for example, the value substituted for the smoothing time constant N in the process of S120 may be a value larger than the first constant N1 and smaller than the second constant N2.

[0061] In the process of S110 shown in Fig. 4, it is determined whether or not the state is transient. In addition, in the process of S110, it may be determined based on other conditions whether to assign a small value or a large value to the smoothing time constant N.

[0062] The required first torque Tmg1* is calculated with reference to the required engine torque Te*. Alternatively, the estimated torque Tee may be referenced instead of the required engine torque Te*.

[0063] The second superimposed torque ΔTmg2* is variably set based on the engine rotation speed NE, the required engine torque Te*, and the second rotation speed Nmg2. Alternatively, the second superimposed torque ΔTmg2* may be set to a predetermined fixed value.

[0064] The compensation process described above is a process in which the second motor-generator 54 generates a compensation torque to compensate for the rotational fluctuation of the crankshaft 26 caused by the torque reduction of the internal combustion engine 10 due to the cessation of combustion in some cylinders. Alternatively, the compensation torque may be generated by increasing the torque of the cylinders in which combustion occurs even during the execution of the stop process.

[0065] The target for stopping combustion during the stop process may be a cylinder other than cylinder #1. The number of cylinders for which combustion is stopped is not limited to one. The cylinders in which combustion is stopped may be switched periodically.

[0066] The stop process is not limited to the regeneration process. For example, when the oxygen storage amount of the three-way catalyst 32 falls below a specified value, the stop process may be a process that stops combustion in only some cylinders to supply oxygen to the three-way catalyst 32, and controls the air-fuel ratio of the mixture in the remaining cylinders to the stoichiometric air-fuel ratio.

[0067] The GPF 34 is not limited to being provided downstream of the three-way catalyst 32 in the exhaust passage 30. Furthermore, it is not essential that the aftertreatment device be provided with a GPF 34. The GPF 34 is not limited to being a filter carrying a three-way catalyst. For example, if a three-way catalyst is provided upstream, the GPF 34 may be a filter alone. Furthermore, the GPF 34 may be a process for stopping combustion in some cylinders in order to adjust the output of the internal combustion engine 10.

[0068] The control device is not limited to one equipped with a CPU 72 and a ROM 74 and executing software processing. For example, it may be equipped with a dedicated hardware circuit, such as an ASIC, that performs hardware processing on at least a portion of the software processing performed in the above embodiments. That is, the control device may have any of the following configurations (a) to (c): (a) equipped with a processing device that executes all of the above processing in accordance with a program, and a program storage device, such as a ROM, that stores the program; (b) equipped with a processing device and program storage device that executes part of the above processing in accordance with a program, and a dedicated hardware circuit that executes the remaining processing; or (c) equipped with a dedicated hardware circuit that executes all of the above processing. Here, the software execution device equipped with a processing device and program storage device, and the dedicated hardware circuit may be one or any multiple number.

[0069] Instead of directly connecting the ring gear R and the second motor generator 54, a reduction gear may be interposed therebetween. The hybrid vehicle is not limited to a series-parallel hybrid vehicle. For example, it may be a parallel hybrid vehicle. [Explanation of symbols]

[0070] 10...Internal combustion engine 16...Port injection valve 20...Combustion chamber 22...In-cylinder injection valve 26...Crankshaft 32...Three-way catalyst 34...GPF 50...Planetary gear mechanism 52...First motor generator 52a...Rotation axis 54...Second motor generator 54a...Rotation axis 56...First inverter 58...Second inverter 59...Battery 60...Drive wheels 70...Control device 80...Air flow meter 82...Crank angle sensor 86...Output side rotation angle sensor 88...Current sensor 89...Voltage sensor 90...First rotation angle sensor 92...Second rotation angle sensor 94...Accelerator sensor 100...Gearbox

Claims

[Claim 1] The present invention is applied to a hybrid vehicle in which a rotating shaft of a rotating electric machine is connected to a crankshaft of an internal combustion engine having a plurality of cylinders, a stop process for stopping combustion in some cylinders of the internal combustion engine; a process of calculating an estimated torque base value based on a torque required for the rotary electric machine and an angular acceleration of the rotary electric machine, and performing an smoothing process on the estimated torque base value using an smoothing time constant to calculate an estimated torque that is an estimated value of a torque output from the internal combustion engine; a process of adjusting a torque output from the rotating electrical machine in accordance with the estimated torque; During the execution of the stop processing, a process is executed in which the smoothing time constant is set to a larger value than when the stop processing is not being executed. A control device for a hybrid vehicle.

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