JP7619046B2 - Vehicle control device - Google Patents

Description

The present invention relates to a vehicle equipped with a clutch between an engine and an electric motor, and to a technology for preventing a decrease in the durability of the clutch when a misfire occurs in the engine.

Vehicle control devices that have a clutch between the engine and the electric motor are well known. For example, the vehicle control device described in Patent Document 1 is one such device. Patent Document 1 describes a technique in which, when it is determined that a misfire has occurred in the engine, the clutch is released, and disturbances due to changes in the road surface are prevented from being transmitted from the drive wheels to the engine, and then a determination is made again as to whether or not a misfire has occurred in the engine.

JP 2009-280082 A

In a vehicle such as that described in Patent Document 1, the clutch is released when a misfire is detected in the engine, and the release of the clutch may cause a sudden drop in driving force, which may cause the driver to feel uncomfortable. In response to this, it is possible to maintain the clutch engaged so that the driving force does not decrease even when a misfire is detected in the engine. However, when a misfire occurs in the engine, the fluctuation in the torque output from the engine increases, and the maximum value of the torque output from the engine may be greater than the maximum value of the torque when the engine is operating normally without a misfire, so there is a problem that when a misfire occurs in the engine, slippage occurs in the clutch and the durability of the clutch decreases. In addition, in order to improve fuel efficiency, the engagement force of the clutch is maintained at a level that does not cause slippage in the clutch when the engine is operating normally. Therefore, when a misfire occurs in the engine and the maximum value of the torque output from the engine becomes greater than the maximum value when the engine is operating normally, the torque output from the engine exceeds the torque capacity of the clutch.

The present invention was made against the background of the above circumstances, and its purpose is to provide a vehicle control device that can prevent the durability of the clutch from decreasing and prevent the driver from feeling uncomfortable when a misfire occurs in the engine.

The gist of the first invention is (a) a control device for a vehicle having a clutch between an engine and an electric motor, (b) when a misfire is detected in the engine, increasing the engagement force of the clutch compared to when a misfire is not detected in the engine , and (c) when a misfire is detected in the engine and the engine torque output from the engine is greater than the torque capacity when the engagement force of the clutch is maximized, reducing the engine torque until it is equal to or less than the torque capacity, and increasing the torque of the electric motor so that the torque output from the electric motor is the amount of torque that has been reduced until the engine torque is equal to or less than the torque capacity .

According to the vehicle control device of the first aspect of the invention, when a misfire is detected in the engine, the engagement force of the clutch is increased compared to when a misfire is not detected in the engine. Therefore, when a misfire occurs in the engine, the engagement force of the clutch is increased, so that slippage of the clutch is suppressed and a decrease in driving force when a misfire occurs in the engine is suppressed. This makes it possible to suppress a decrease in durability of the clutch and to suppress a sense of discomfort felt by the driver when a misfire occurs in the engine. Furthermore, when a misfire is detected in the engine and the engine torque output from the engine is greater than the torque capacity when the engagement force of the clutch is maximized, the engine torque is reduced until it is equal to or less than the torque capacity, and the torque of the electric motor is increased so that the torque equivalent to the torque reduced until the engine torque is equal to or less than the torque capacity is output from the electric motor. Therefore, even when the engine torque when a misfire occurs in the engine is greater than the torque capacity, slippage of the clutch can be suitably suppressed.

Here , preferably, when it is detected that a misfire has occurred in the engine, if the engine torque output from the engine is greater than the torque capacity when the engagement force of the clutch is maximized, the engine is stopped and the clutch is released, and the torque of the electric motor is increased so that the torque output from the electric motor is equal to the engine torque output from the engine. Therefore, by stopping the engine, torque fluctuations caused by engine misfire are eliminated, and drivability is preferably improved.

1 is a diagram for explaining a schematic configuration of a vehicle to which the present invention is applied, and is also a diagram for explaining main parts of control functions and a control system for various controls in the vehicle. 2 is a flowchart illustrating a main part of the control operation of the electronic control device of FIG. 1, and is a flowchart illustrating an example of the control operation of the engagement control of the K0 clutch when a misfire occurs in the engine. 3 is a diagram showing an example of a time chart when the control operation shown in the flowchart of FIG. 2 is executed. FIG. FIG. 11 is a diagram illustrating a configuration of an electronic control device for a vehicle according to another embodiment (embodiment 2) of the present invention. 5 is a flowchart illustrating the main control operations of the electronic control device of FIG. 4, and is a flowchart illustrating an example of the control operations of the engagement control of the K0 clutch and the hybrid drive control by the engine and the electric motor when a misfire occurs in the engine. 6 is a diagram showing an example of a time chart when the control operation shown in the flowchart of FIG. 5 is executed. FIG. FIG. 13 is a diagram illustrating the configuration of an electronic control device for a vehicle according to another embodiment (third embodiment) of the present invention. 8 is a flowchart illustrating the main control operations of the electronic control device of FIG. 7, and is a flowchart illustrating an example of the control operations of the engagement control of the K0 clutch and the hybrid drive control by the engine and the electric motor when a misfire occurs in the engine. 9 is a diagram showing an example of a time chart when the control operation shown in the flowchart of FIG. 8 is executed.

The following describes in detail an embodiment of the present invention with reference to the drawings.

Figure 1 is a diagram illustrating the general configuration of a vehicle 10 to which the present invention is applied, as well as a diagram illustrating the main parts of the control functions and control system for various controls in the vehicle 10. In Figure 1, the vehicle 10 is a hybrid vehicle equipped with an engine 12 and an electric motor MG, which are driving power sources for traveling. The vehicle 10 also has driving wheels 14 and a power transmission device 16 provided in the power transmission path between the engine 12 and the driving wheels 14.

The engine 12 is a known internal combustion engine such as a gasoline engine or a diesel engine. The engine 12 has an engine control device 50, which includes a throttle actuator, a fuel injection device, an ignition device, and the like, provided on the vehicle 10, controlled by an electronic control device 100 (described later), thereby controlling the engine torque Te, which is the output torque of the engine 12.

The electric motor MG is a rotating electric machine that functions as a motor to generate mechanical power from electric power and as a generator to generate electric power from mechanical power, and is a so-called motor generator. The electric motor MG is connected to a battery 54 provided in the vehicle 10 via an inverter 52 provided in the vehicle 10. The electric motor MG controls the MG torque (torque) Tm, which is the output torque of the electric motor MG, by controlling the inverter 52 by an electronic control device 100 described later. For example, when the rotation direction of the electric motor MG is the same as the rotation direction when the engine 12 is operating, the MG torque Tm is a power torque in the positive torque on the acceleration side, and a regenerative torque in the negative torque on the deceleration side. Specifically, the electric motor MG generates power for running using electric power supplied from the battery 54 via the inverter 52 instead of or in addition to the engine 12. The electric motor MG also generates power using the power of the engine 12 and the driven force input from the drive wheels 14 side. The electric power generated by the electric motor MG is stored in the battery 54 via the inverter 52. The battery 54 is an electric storage device that supplies electric power to the electric motor MG. The electric power is also synonymous with electrical energy unless otherwise specified. The motive power is also synonymous with torque and force unless otherwise specified.

The power transmission device 16 includes a K0 clutch 20, a torque converter 22 with an LU clutch 22a, an automatic transmission 24, and the like, in a case 18, which is a non-rotating member attached to the vehicle body. The K0 clutch 20 is a clutch provided between the engine 12 and the electric motor MG in the power transmission path between the engine 12 and the drive wheels 14. A damper 26 and a flywheel 28 are provided between the engine 12 and the K0 clutch 20. As shown in FIG. 1, the engine 12 is connected to the torque converter 22 and the automatic transmission 24 via the K0 clutch 20 so that the engine 12 can transmit power, i.e., the engine 12 is connected to the drive wheels 14 via the K0 clutch 20 so that the engine 12 can transmit power. The electric motor MG is connected to the torque converter 22 and the automatic transmission 24 so that the electric motor MG can transmit power without the K0 clutch 20, i.e., the electric motor MG is connected to the drive wheels 14 so that the electric motor MG can transmit power without the K0 clutch 20. The torque converter 22 and the automatic transmission 24 transmit the driving force from the driving force sources, the engine 12 and the electric motor MG, respectively, to the drive wheels 14.

The LU clutch 22a switches its operating state, i.e., its control state, by changing the LU clutch torque Tlu, which is the torque capacity of the LU clutch 22a, using the regulated LU hydraulic pressure PRlu supplied from the hydraulic control circuit 56 provided in the vehicle 10.

The automatic transmission 24 is a known planetary gear type automatic transmission that includes, for example, one or more planetary gear sets (not shown) and multiple engagement devices CB. The engagement devices CB are hydraulic friction engagement devices that are composed of, for example, multi-plate or single-plate clutches or brakes pressed by a hydraulic actuator, or band brakes tightened by a hydraulic actuator. The engagement devices CB have their respective torque capacities, or CB torques Tcb, changed by the regulated CB hydraulic pressure PRcb supplied from the hydraulic control circuit 56, thereby switching between control states such as an engaged state and a disengaged state.

The automatic transmission 24 is a stepped transmission in which one of a plurality of gear stages (also called gear stages) with different speed ratios (also called gear ratios) γat (=AT input rotation speed Ni/AT output rotation speed No) is formed by engaging one of the engagement devices CB. The automatic transmission 24 selectively forms a plurality of gear stages by switching the gear stages formed according to the accelerator operation of the driver (=operator) and the vehicle speed V, etc., by the electronic control device 100 described later. The AT input rotation speed Ni is the input rotation speed of the automatic transmission 24, and the AT output rotation speed No is the output rotation speed of the automatic transmission 24.

The K0 clutch 20 is a wet or dry friction engagement device, for example, configured with a multi-plate or single-plate clutch. The control state of the K0 clutch 20, such as an engaged state or a released state, is switched by the electronic control device 100, which will be described later. The control state of the K0 clutch 20 is switched by changing the clutch engagement force (engagement force) Fk0 of the K0 clutch 20, i.e., the K0 torque Tk0, which is the torque capacity of the K0 clutch 20, by the K0 hydraulic pressure PRk0 supplied from the hydraulic control circuit 56.

The vehicle 10 further includes an electronic control device 100 that includes a control device for the vehicle 10 related to driving control, etc. The electronic control device 100 includes a so-called microcomputer equipped with, for example, a CPU, RAM, ROM, an input/output interface, etc., and the CPU executes various controls of the vehicle 10 by performing signal processing according to a program previously stored in the ROM while utilizing the temporary storage function of the RAM. The electronic control device 100 includes computers for engine control, electric motor control, hydraulic control, etc. as necessary.

The electronic control device 100 is supplied with various signals based on the detection values of various sensors (e.g., engine speed sensor 70, turbine speed sensor 72, output speed sensor 74, MG speed sensor 76, accelerator opening sensor 78, throttle valve opening sensor 80, battery sensor 82, etc.) provided in the vehicle 10 (e.g., engine speed Ne, which is the rotation speed of the engine 12; turbine speed Nt, which is the same value as AT input rotation speed Ni; AT output rotation speed No, which corresponds to the vehicle speed V; MG speed Nm, which is the rotation speed of the electric motor MG; accelerator opening θacc, which is the driver's accelerator operation amount indicating the magnitude of the driver's acceleration operation; throttle valve opening θth, which is the opening of the electronic throttle valve; battery temperature THbat, battery charge/discharge current Ibat, battery voltage Vbat, etc.) of the battery 54.

The electronic control device 100 outputs various command signals (e.g., engine control command signal Se for controlling the engine 12, MG control command signal Sm for controlling the electric motor MG, CB hydraulic control command signal Scb for controlling the engagement device CB, K0 hydraulic control command signal Sk0 for controlling the K0 clutch 20, LU hydraulic control command signal Slu for controlling the LU clutch 22a, etc.) to each device (e.g., engine control device 50, inverter 52, hydraulic control circuit 56, etc.) provided in the vehicle 10.

The electronic control device 100 includes a hybrid control means, i.e., a hybrid control unit 102, a clutch control means, i.e., a clutch control unit 104, and a misfire detection means, i.e., a misfire detection unit 106, in order to realize various controls in the vehicle 10.

The hybrid control unit 102 includes a function as an engine control means, i.e., engine control unit 102a, that controls the operation of the engine 12, and a function as an electric motor control means, i.e., electric motor control unit 102b, that controls the operation of the electric motor MG via the inverter 52, and executes hybrid drive control using the engine 12 and the electric motor MG, etc., by using these control functions.

The hybrid control unit 102 calculates the driving demand amount of the vehicle 10 by the driver, for example, by applying the accelerator opening θacc and the vehicle speed V to a driving demand amount map. The driving demand amount map is a relationship that is experimentally or design-wise determined and stored in advance, i.e., a predetermined relationship. The driving demand amount is, for example, the required driving torque Trdem [Nm] at the driving wheels 14. In other words, the required driving torque Trdem [Nm] is the required driving power Prdem [W] at the vehicle speed V at that time. The driving demand amount can also be the required driving force Frdem [N] at the driving wheels 14, the required AT output torque at the output shaft of the automatic transmission 24, etc. In calculating the driving demand amount, the AT output rotation speed No [rpm], etc. may be used instead of the vehicle speed V.

The hybrid control unit 102 outputs an engine control command signal Se for controlling the engine 12 and an MG control command signal Sm for controlling the electric motor MG so as to realize the required driving power Prdem, taking into consideration the transmission loss, the auxiliary load, the gear ratio γat of the automatic transmission 24, the chargeable power Win and dischargeable power Wout of the battery 54, etc. The engine control command signal Se is, for example, a command value for the engine power Pe, which is the power of the engine 12 that outputs the engine torque Te at the current engine rotation speed Ne. The MG control command signal Sm is, for example, a command value for the power consumption Wm of the electric motor MG that outputs the MG torque Tm at the current MG rotation speed Nm.

The chargeable power Win of the battery 54 is the maximum power that can be input, which specifies the limit on the input power of the battery 54, and indicates the input limit of the battery 54. The dischargeable power Wout of the battery 54 is the maximum power that can be output, which specifies the limit on the output power of the battery 54, and indicates the output limit of the battery 54. The chargeable power Win and dischargeable power Wout of the battery 54 are calculated by the electronic control unit 100, for example, based on the battery temperature THbat and the state of charge value SOC [%] of the battery 54. The state of charge value SOC of the battery 54 is a value that indicates the remaining charge of the battery 54, and is calculated by the electronic control unit 100, for example, based on the battery charge/discharge current Ibat and the battery voltage Vbat.

When the required drive torque Trdem can be satisfied only by the output of the electric motor MG, the hybrid control unit 102 sets the driving mode to the motor driving (=EV driving) mode. In the EV driving mode, the hybrid control unit 102 performs EV driving, in which the vehicle runs using only the electric motor MG as a driving force source with the K0 clutch 20 in the released state. On the other hand, when the required drive torque Trdem cannot be satisfied without using at least the output of the engine 12, the hybrid control unit 102 sets the driving mode to the engine driving mode, i.e., hybrid driving (=HV driving) mode. In the HV driving mode, the hybrid control unit 102 performs engine driving, i.e., HV driving, in which the vehicle runs using at least the engine 12 as a driving force source with the K0 clutch 20 in the engaged state. On the other hand, even if the required drive torque Trdem can be satisfied only by the output of the electric motor MG, the hybrid control unit 102 establishes the HV driving mode when the state of charge value SOC of the battery 54 is less than a predetermined engine start threshold value or when the engine 12, etc., needs to be warmed up. The engine start threshold is a predetermined threshold for determining that the state of charge value SOC is at a value at which it is necessary to forcibly start the engine 12 and charge the battery 54. In this way, the hybrid control unit 102 switches between the EV driving mode and the HV driving mode by automatically stopping the engine 12 during HV driving, restarting the engine 12 after the engine has stopped, or starting the engine 12 during EV driving, based on the required driving torque Trdem, etc.

The clutch control unit 104 controls the clutch engagement force Fk0 of the K0 clutch 20 according to the running state of the vehicle 10. For example, the clutch control unit 104 controls the clutch engagement force Fk0 [N] of the K0 clutch 20 so that the force exceeds the output torque of the engine 12, i.e., the force does not cause slippage in the K0 clutch 20, during at least HV running using the engine 12 as a driving force source, and maintains the engaged state. In addition, the clutch control unit 104 releases the K0 clutch 20 during EV running using only the electric motor MG as a driving force source. The above clutch engagement force Fk0 is the fastening force of the K0 clutch 20, and is the pressing force of the K0 clutch 20 against the friction plates.

The misfire detection unit 106 determines whether or not a misfire has occurred in the engine 12. For example, the misfire detection unit 106 measures the amplitude A [rpm] (see FIG. 3) of the engine speed Ne using the engine speed sensor 70, and determines that a misfire has occurred in the engine 12 when the amplitude A of the engine speed Ne exceeds a predetermined misfire determination value Aj [rpm]. When the misfire detection unit 106 detects that a misfire has occurred in the engine 12, the electronic control unit 100 turns on a warning light provided on a meter panel (not shown) to notify the driver that a misfire has occurred in the engine 12. The misfire determination value Aj is a predetermined determination value of the amplitude A for determining that a misfire has occurred in the engine 12.

When the misfire detection unit 106 detects that the engine 12 has misfired, the clutch control unit 104 increases the clutch engagement force Fk0 of the K0 clutch 20 compared to when the engine 12 has not detected that the engine 12 has misfired. For example, when the misfire detection unit 106 detects that the engine 12 has misfired, the clutch control unit 104 increases the clutch engagement force Fk0 by a predetermined engagement force increase amount Fup [Nm] (see FIG. 3) compared to the clutch engagement force Fk0 when the misfire detection unit 106 determines that the engine 12 has not detected that the engine 12 has misfired. The engagement force increase amount Fup is set, for example, based on the maximum value of the engine torque Te, that is, the engagement force increase amount Fup is set so that the engagement force increase amount Fup increases as the maximum value of the engine torque Te increases, or the engagement force increase amount Fup is set so that the engagement force increase amount Fup decreases as the maximum value of the engine torque Te decreases. The engine torque Te used to set the engagement force increase amount Fup may be, for example, actually measured by a torque sensor or estimated from the rotational fluctuation (rotational acceleration) of the engine rotation speed Ne. In addition, in the clutch control unit 104, when the misfire detection unit 106 detects that a misfire has occurred in the engine 12, and then the amplitude A of the engine rotation speed Ne becomes equal to or less than the misfire judgment value Aj and the misfire detection unit 106 no longer detects that a misfire has occurred in the engine 12, the engagement force increase amount Fup is set to zero.

Figure 2 is a flowchart explaining the main control operations of the electronic control unit 100, and is a flowchart explaining an example of the control operation of the engagement control of the K0 clutch 20 when a misfire occurs in the engine 12. Also, Figure 3 is a diagram showing an example of a time chart when the control operation shown in the flowchart of Figure 2 is executed. Note that the time chart of Figure 3 shows the change in engine torque Te [Nm], engine speed Ne [rpm], and clutch engagement force Fk0 [N] over time t [sec]. In Figure 3, tA is the time when it is detected that a misfire has occurred in the engine 12 (misfire determination). Also, the flowchart of Figure 2 starts when the vehicle 10 is running in HV mode.

First, in step S10 (hereinafter, step will be omitted) corresponding to the function of the misfire detection unit 106, it is determined whether or not a misfire has been detected in the engine 12. If the determination in S10 is negative, this routine is terminated. If the determination in S10 is positive (time tA in FIG. 3), S20 corresponding to the function of the clutch control unit 104 is executed. In S20, the clutch engagement force Fk0 of the K0 clutch 20 is increased compared to when a misfire has not been detected in the engine 12.

As described above, according to the electronic control device 100 of the vehicle 10 of this embodiment, when a misfire is detected in the engine 12, the clutch engagement force Fk0 of the K0 clutch 20 is increased compared to when a misfire is not detected in the engine 12. Therefore, when a misfire occurs in the engine 12, the clutch engagement force Fk0 of the K0 clutch 20 is increased, thereby suppressing slippage of the K0 clutch 20 and suppressing a decrease in driving force when a misfire occurs in the engine 12. This makes it possible to suppress a decrease in the durability of the K0 clutch 20 and to suppress a sense of discomfort felt by the driver when a misfire occurs in the engine 12.

Next, we will explain other embodiments of the present invention. In the following explanation, parts common to the embodiments will be given the same reference numerals and explanations will be omitted.

Figure 4 is a diagram illustrating the configuration of an electronic control device (control device) 150 of a vehicle 10 according to another embodiment (embodiment 2) of the present invention. The electronic control device 150 of the vehicle 10 of this embodiment is substantially the same as the electronic control device 100 of the vehicle 10 of embodiment 1, except that the electronic control device 150 is provided with an engine torque determination means, i.e., an engine torque determination unit 152.

When the misfire detection unit 106 determines that a misfire has occurred in the engine 12, the engine torque determination unit 152 determines whether the engine torque Te [Nm] is greater than a predetermined clutch allowable torque Tk0max [Nm]. The engine torque Te used in the engine torque determination unit 152 may be, for example, actually measured by a torque sensor or the like, or may be estimated from the rotational fluctuation (rotational acceleration) of the engine rotation speed Ne. The clutch allowable torque Tk0max is the torque capacity when the clutch engagement force Fk0 of the K0 clutch 20 is maximized.

When a predetermined first condition CD1 is satisfied, the engine control unit 102a controls the engine torque Te so that the maximum value of the engine torque Te is equal to or less than the clutch allowable torque Tk0max. The first condition CD1 is satisfied when the misfire detection unit 106 detects that a misfire has occurred in the engine 12 and the engine torque determination unit 152 determines that the engine torque Te is greater than the clutch allowable torque Tk0max.

When the first condition CD1 is satisfied, the motor control unit 102b controls the MG torque Tm so that the torque that has been reduced by the engine control unit 102a until the engine torque Te becomes equal to or less than the clutch allowable torque Tk0max is output from the motor MG.

When the first condition CD1 is satisfied, the clutch control unit 104 increases the clutch engagement force Fk0 of the K0 clutch 20 so that the clutch engagement force Fk0 of the K0 clutch 20 is, for example, maximized. When a predetermined second condition CD2 is satisfied, the clutch control unit 104 increases the clutch engagement force Fk0 of the K0 clutch 20 by the engagement force increase amount Fup, as in the function of the clutch control unit 104 in the first embodiment, compared to when a misfire has not been detected in the engine 12. The second condition CD2 is satisfied when the misfire detection unit 106 detects that a misfire has occurred in the engine 12, and the engine torque determination unit 152 determines that the engine torque Te is not greater than the clutch allowable torque Tk0max, i.e., when the engine torque determination unit 152 determines that the engine torque Te is equal to or less than the clutch allowable torque Tk0max.

Figure 5 is a flowchart explaining the main part of the control operation of the electronic control unit 150, and is a flowchart explaining an example of the control operation of the engagement control of the K0 clutch 20 when a misfire occurs in the engine 12 and the hybrid drive control by the engine 12 and the electric motor MG. Also, Figure 6 is a diagram showing an example of a time chart when the control operation shown in the flowchart of Figure 5 is executed. Note that the time chart of Figure 6 shows the change in time t [sec] of the engine torque Te [Nm], the engine command torque Te_S [Nm] which is a signal output to the engine control unit 50 to control the engine torque Te, the motor command torque Tm_S [Nm] which is a signal output to the inverter 52 to control the MG torque Tm, and the clutch engagement force Fk0 [N]. In Figure 6, tB is the time when the first condition CD1 is established. Also, the flowchart of Figure 5 starts when the vehicle 10 is running in HV mode. Note that S10 in the flowchart in Figure 5 is the same as S10 in the flowchart in Figure 2, so below we will omit the explanation of S10 and explain the flowchart in Figure 5.

If the determination in S10 is positive, S110, which corresponds to the function of the engine torque determination unit 152, is executed. In S110, it is determined whether the engine torque Te is greater than the clutch allowable torque Tk0max. If the determination in S110 is negative, that is, if the second condition CD2 is satisfied, S120, which corresponds to the function of the clutch control unit 104, is executed. In S120, the clutch engagement force Fk0 of the K0 clutch 20 is increased compared to when it is not detected that a misfire has occurred in the engine 12.

When the determination in S110 is positive (time tB in FIG. 6), that is, when the first condition CD1 is satisfied, S130 corresponding to the functions of the engine control unit 102a, the electric motor control unit 102b, and the clutch control unit 104 is executed. In S130, the engine torque Te is reduced until it becomes equal to or less than the clutch allowable torque Tk0max, the clutch engagement force Fk0 is increased to be maximized, and the torque by which the engine torque Te is reduced until it becomes equal to or less than the clutch allowable torque Tk0max is output from the electric motor MG.

As described above, according to the electronic control device 150 of the vehicle 10 of this embodiment, when it is detected that the engine 12 has misfired, if the engine torque Te output from the engine 12 is greater than the clutch allowable torque Tk0max, which is the torque capacity when the clutch engagement force Fk0 of the K0 clutch 20 is maximized, the engine torque Te is reduced to less than the clutch allowable torque Tk0max, and the MG torque Tm of the electric motor MG is increased so that the torque output from the electric motor MG is the amount of torque that has been reduced until the engine torque Te is less than the clutch allowable torque Tk0max. Therefore, even if the engine torque Te when the engine 12 has misfired is greater than the clutch allowable torque Tk0max, slippage of the K0 clutch 20 can be suitably suppressed.

Figure 7 is a diagram illustrating the configuration of an electronic control device (control device) 200 of a vehicle 10 in another embodiment (embodiment 3) of the present invention. The electronic control device 200 of the vehicle 10 in this embodiment differs in that the control operations of the hybrid control unit 102 and the clutch control unit 104 when the first condition CD1 is satisfied are different, but otherwise is substantially the same as the electronic control device 150 of the vehicle 10 in embodiment 2.

When the first condition CD1 is satisfied, the engine control unit 102a stops the engine 12 and sets the engine torque Te to zero.

When the first condition CD1 is satisfied, the motor control unit 102b controls the MG torque Tm so that the torque output from the motor MG is equal to the engine torque Te output from the engine 12.

When the first condition CD1 is satisfied, the clutch control unit 104 sets the clutch engagement force Fk0 of the K0 clutch 20 to zero and releases the K0 clutch 20.

Figure 8 is a flowchart explaining the main parts of the control operation of the electronic control unit 200, and is a flowchart explaining an example of the control operation of the engagement control of the K0 clutch 20 when a misfire occurs in the engine 12 and the hybrid drive control by the engine 12 and the electric motor MG. Also, Figure 9 is a diagram showing an example of a time chart when the control operation shown in the flowchart of Figure 8 is executed. Note that the time chart of Figure 9 shows the change in time t [sec] of the engine torque Te [Nm], the engine command torque Te_S [Nm], the motor command torque Tm_S [Nm], and the clutch engagement force Fk0 [N]. In Figure 9, tC is the time when the first condition CD1 is established. Also, the flowchart of Figure 8 starts when the vehicle 10 is running in HV mode. Note that S10, S110, and S120 in the flowchart in Figure 8 are the same as S10, S110, and S120 in the flowchart in Figure 5, so below we will omit the explanation of S10, S110, and S120 and explain the flowchart in Figure 8.

When the determination in S110 is positive (time tC in FIG. 9), that is, when the first condition CD1 is satisfied, S200, which corresponds to the functions of the engine control unit 102a, the electric motor control unit 102b, and the clutch control unit 104, is executed. In S200, the engine 12 is stopped, the K0 clutch 20 is released, and the torque equivalent to the engine torque Te output from the engine 12 is output from the electric motor MG.

As described above, according to the electronic control device 200 of the vehicle 10 of this embodiment, when a misfire is detected in the engine 12, if the engine torque Te output from the engine 12 is greater than the clutch allowable torque Tk0max, which is the torque capacity when the clutch engagement force Fk0 of the K0 clutch 20 is maximized, the engine 12 is stopped and the K0 clutch 20 is released, and the MG torque Tm of the electric motor MG is increased so that the torque equivalent to the engine torque Te output from the engine 12 is output from the electric motor MG. Therefore, by stopping the engine 12, torque fluctuations caused by a misfire in the engine 12 are eliminated, and drivability is suitably improved.

The above describes in detail an embodiment of the present invention based on the drawings, but the present invention can also be applied in other aspects.

For example, in the misfire detection unit 106 of the above embodiment, the amplitude A of the engine speed Ne is measured by the engine speed sensor 70, and when the amplitude A of the engine speed Ne exceeds the misfire determination value Aj, it is detected that a misfire has occurred in the engine 12. However, for example, it is also possible to detect that a misfire has occurred in the engine 12 by a method other than this.

In addition, in the above-described first embodiment, when the misfire detection unit 106 detects that a misfire has occurred in the engine 12, the clutch engagement force Fk0 of the K0 clutch 20 is increased by the engagement force increase amount Fup. However, for example, when the misfire detection unit 106 detects that a misfire has occurred in the engine 12, the clutch engagement force Fk0 of the K0 clutch 20 may be increased to its maximum.

The above is merely one embodiment, and the present invention can be implemented in various forms with various modifications and improvements based on the knowledge of those skilled in the art.

10: Vehicle 12: Engine 20: K0 clutch 100, 150, 200: Electronic control unit (control unit)
104: Clutch control unit 106: Misfire detection unit Fk0: Clutch engagement force (engagement force)
MG: Electric motor

Claims (1)

A control device for a vehicle having a clutch between an engine and an electric motor,
A vehicle control device characterized in that, when a misfire is detected in the engine, the engagement force of the clutch is increased compared to when a misfire is not detected in the engine, and, when a misfire is detected in the engine and the engine torque output from the engine is greater than a torque capacity when the engagement force of the clutch is maximized, the engine torque is reduced until it is equal to or less than the torque capacity, and the torque of the electric motor is increased so that the torque output from the electric motor is the amount of torque by which the engine torque is reduced until it is equal to or less than the torque capacity .

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