JP7211264B2 - Hybrid vehicle control device - Google Patents

Description

The present invention relates to a hybrid vehicle control device.

Patent Literature 1 describes an example of a hybrid vehicle that includes an internal combustion engine, a motor generator, and a power split device. In this hybrid vehicle, the power split mechanism has a plurality of gears that mesh with each other. Among the plurality of gears, the internal combustion engine is connected to the first gear, and the motor generator is connected to the second gear. Then, in order to suppress looseness between the gears that mesh with each other, a push-down process is executed to cause the motor generator to output torque in a direction that increases the load applied to the internal combustion engine.

JP 2011-245986 A

When the push-down process is executed, the load applied to the internal combustion engine increases. Therefore, when the combustion of the air-fuel mixture in the cylinder of the internal combustion engine becomes unstable during the execution of the push-down process, there is concern that misfire may occur in the internal combustion engine.

A control device for a hybrid vehicle for solving the above-described problems includes an internal combustion engine, a motor generator, and a power split device having a plurality of gears that mesh with each other, and outputs torque from the internal combustion engine to the motor generator. It is applied to a hybrid vehicle that causes the motor generator to generate power by inputting through the . This control device includes a combustion determination section that determines whether or not an air-fuel mixture is stably combusted in a cylinder of the internal combustion engine while the engine is running, and a motor control section that controls the motor generator. , is equipped with Then, when it is determined that the air-fuel mixture is stably combusted in the cylinder, the motor control unit executes a push-down process that causes the motor generator to output torque in a direction that increases the load applied to the internal combustion engine. On the other hand, when it is not determined that the air-fuel mixture is stably burning in the cylinder, the push-down process is not executed.

According to the above configuration, the push-down process is not executed when it is not determined that the air-fuel mixture is stably combusted in the cylinder. Therefore, it is possible to suppress the occurrence of a misfire in the internal combustion engine that accompanies the execution of the push-down process.

One aspect of the hybrid vehicle control device is that when the torque output from the motor generator by the execution of the push-down process is set to be the first motor torque, the motor control unit determines that the air-fuel mixture is stably combusted in the cylinder. is not determined, a push-up process is executed to cause the motor generator to output the second motor torque, which is torque in the opposite direction to the direction of the first motor torque.

According to the above configuration, the boost process is executed when it is not determined that the air-fuel mixture is stably combusted in the cylinder. In the push-up process, the second motor torque is output from the motor generator. Therefore, unlike the case where the push-down process is executed, the load applied to the internal combustion engine by driving the motor generator can be reduced. By operating the engine with the load reduced in this manner, the fuel efficiency of the internal combustion engine can be improved.

It should be noted that when the push-down process is executed, the load applied to the internal combustion engine increases, resulting in deterioration of the fuel consumption of the internal combustion engine. In addition, the higher the vehicle speed, the louder the running sound generated when the vehicle is running. Therefore, when the vehicle speed is high, even if abnormal noise is generated due to rattling of the gears meshing with each other in the power split mechanism, it is difficult for the occupants of the vehicle to feel uncomfortable due to the generation of the abnormal noise.

Therefore, when the vehicle speed is equal to or higher than the determination vehicle speed, it is preferable that the motor control unit does not execute the push-down process even if it is determined that the air-fuel mixture is stably combusted in the cylinder. According to this configuration, when the vehicle speed is equal to or higher than the determination vehicle speed, the pressing process is not executed because the running noise is loud. By reducing the number of opportunities to execute the push-down process in this way, it is possible to suppress deterioration in fuel consumption of the internal combustion engine.

By the way, an internal combustion engine includes an EGR device that recirculates exhaust gas discharged from a cylinder into an exhaust passage to the intake passage as EGR gas, and a catalyst provided in the exhaust passage. The EGR device may be provided with an EGR valve that adjusts the amount of In this case, when the amount of decrease in the required engine output, which is the required output of the internal combustion engine, is less than the determined amount of decrease, the control device adjusts the opening of the throttle valve provided in the intake passage according to the change in the required engine output. and a normal processing section that adjusts the opening of the EGR valve, and when the reduction amount of the requested engine output is equal to or greater than the judgment reduction amount, the reduction speed of the EGR valve opening becomes higher than the reduction speed of the throttle valve opening. and a rapid decrease processing unit that executes rapid decrease processing for decreasing the opening degree of the throttle valve and the opening degree of the EGR valve.

If the ratio of the intake air to the gas introduced into the cylinder of the internal combustion engine is too small, the internal combustion engine may misfire. Therefore, when the opening of the throttle valve is reduced because the required engine output is reduced, the opening of the EGR valve is reduced in accordance with the reduction in the opening of the throttle valve. However, if the responsiveness of the EGR valve is worse than the responsiveness of the throttle valve, even if the opening of the EGR valve is decreased in accordance with the decrease in the opening of the throttle valve, there will be no suction due to the decrease in the opening of the throttle valve. The decrease in the amount of EGR gas recirculated to the intake passage may be delayed with respect to the decrease in air amount. If such a delay occurs, the ratio of the intake air to the gas introduced into the cylinder becomes too small, and misfire may occur in the internal combustion engine.

When the amount of decrease in the requested engine output is equal to or greater than the determination amount of decrease, the amount of intake air is greatly decreased, so the ratio of the intake air to the gas introduced into the cylinder tends to decrease. Therefore, according to the above configuration, when the amount of decrease in the required engine output is equal to or greater than the determination amount of decrease, the speed of decrease in the degree of opening of the EGR valve is higher than the speed of decrease in the degree of opening of the throttle valve. The degree of opening and the degree of opening of the EGR valve are reduced. By decreasing the opening of the EGR valve with priority over the opening of the throttle valve in this way, the amount of EGR gas recirculated to the intake passage relative to the decrease in intake air caused by the decrease in the opening of the throttle valve is suppressed. As a result, it is possible to prevent the intake air from becoming too small in the gas introduced into the cylinder. Therefore, it is possible to suppress the occurrence of misfires in the internal combustion engine when the required engine output is greatly reduced.

In the rapid decrease processing, the rapid decrease processing unit preferably closes the EGR valve and then decreases the opening of the throttle valve. With this configuration, when the required engine output is reduced, it is possible to prevent the intake air from becoming too small in the gas introduced into the cylinder.

In one aspect of the control device for a hybrid vehicle, in the rapid decrease processing, the rapid decrease processing unit sets the opening of the throttle valve so that the opening corresponds to the larger value of the required engine output and the lower limit guard. to adjust. In this control device, the motor control unit drives the motor generator so that, when the lower limit guard is greater than the required engine output, the amount of power generated by the motor generator corresponds to the difference between the lower limit guard and the required engine output. Execute the power generation process to

According to the above configuration, when the required engine output decreases and the lower limit guard is larger than the required engine output, the opening of the throttle valve is made to correspond to the lower limit guard. That is, a decrease in the opening degree of the throttle valve is suppressed, and a decrease in the amount of intake air is thus suppressed. As a result, it is possible to prevent the intake air from becoming too small in the gas introduced into the cylinder. Then, when the lower limit guard is greater than the requested engine output, the drive of the motor generator is controlled so that the power generation amount corresponds to the difference between the lower limit guard and the requested engine output. As a result, deterioration in the controllability of the torque transmitted to the driving wheels of the vehicle can be suppressed.

If the amount of intake air is significantly reduced while the EGR rate is high, the ratio of the intake air to the gas introduced into the cylinder tends to be too small. Therefore, the hybrid vehicle control device preferably includes a guard setting unit that sets the lower limit guard so that the lower limit guard increases as the EGR rate increases during execution of the rapid decrease process.

According to the above configuration, when the EGR rate is high, the intake air amount is less likely to decrease because the lower limit guard is large. As a result, it is possible to prevent the intake air from becoming too small in the gas introduced into the cylinder. On the other hand, when the EGR rate decreases due to a decrease in the degree of opening of the EGR valve, the lower limit guard becomes smaller. Then, the opening degree of the throttle valve is decreased according to the decrease of the lower limit card. As a result, the engine output can be reduced, and the deviation between the engine output and the required engine output can be reduced.

One aspect of the hybrid vehicle control device includes an ignition timing adjustment unit that adjusts the ignition timing of the internal combustion engine. In this control device, the motor control unit executes the power generation process when the rapid decrease process is executed under the condition that the storage amount of the battery that stores the electric power generated by the motor generator is less than the determination storage amount. , the power generation process is not executed when the sudden decrease process is executed under the condition that the stored power amount is equal to or greater than the judgment stored power amount. Further, the ignition timing adjustment unit retards the ignition timing when the sudden decrease process is executed in a situation where the stored electricity amount is equal to or greater than the determined stored electricity amount, thereby suppressing the divergence between the engine output and the requested engine output. Execute ignition timing retardation processing.

According to the above configuration, when the state of charge in the battery is less than the determined state of charge during execution of the rapid drop process, it is determined that the power generated by the motor generator during execution of the rapid drop process can be stored in the battery, and power generation is performed. Processing is performed. On the other hand, if the power generation process is executed when the amount of stored electricity is equal to or greater than the determined amount of stored electricity, the amount of stored electricity may become excessive. Therefore, when the stored electricity amount is equal to or greater than the determined stored electricity amount, the power generation process is not performed while the rapid decrease process is being performed. In this case, ignition timing retardation processing is executed. By retarding the ignition timing by executing the ignition timing retarding process, the occurrence of deviation between the engine output and the required engine output during the rapid decrease process is suppressed. As a result, deterioration in the controllability of the torque transmitted to the driving wheels of the vehicle can be suppressed without executing the power generation process.

It should be noted that, in cases such as when deposits are attached to the throttle valve, the amount of intake air may become smaller than the amount corresponding to the required engine output. When the required engine output is significantly reduced, if the amount of intake air becomes too small, there is a risk of misfire occurring in the internal combustion engine. When a misfire occurs, more unburned fuel reaches the catalyst. If such unburned fuel burns in the catalyst, the temperature of the catalyst may become too high.

Therefore, the injection valve control unit stops the fuel injection of the fuel injection valve on the condition that the intake air amount is equal to or less than the determination intake air amount when the opening degree of the throttle valve is decreased by executing the rapid decrease process. A fuel cut process may be started.

According to the above configuration, when the opening degree of the throttle valve is decreased by executing the sudden decrease process, and the intake air amount is less than the determined intake air amount, the intake air amount becomes too small and misfire occurs in the internal combustion engine. Since it can be determined that there is a risk of occurrence, fuel cut processing is executed. When the fuel cut process is executed, fuel injection is stopped, so that unburned fuel does not reach the catalyst. As a result, it is possible to prevent the temperature of the catalyst from becoming too high.

For example, when the opening of the throttle valve is decreased by executing the rapid decrease process, the injection valve control unit is set to start fuel cut processing. In this case, it is preferable that the judgment continuation time is shortened as the amount of EGR gas recirculated to the intake passage by the EGR device increases, shortened as the amount of intake air decreases, and shortened as the engine speed increases.

According to the above configuration, when the opening degree of the throttle valve is decreased by executing the sudden decrease process, and the state in which the intake air amount is less than the determination intake air amount continues for the determination continuation time or longer, the internal combustion engine Since it can be determined that misfire may occur, fuel cut processing is executed.

Incidentally, misfiring is more likely to occur as the amount of EGR gas recirculated to the intake passage increases. Also, the smaller the amount of intake air, the more likely misfires will occur. Also, the higher the engine speed, the more likely misfires will occur.

In this respect, according to the above configuration, the duration of determination is set according to the amount of EGR gas recirculated to the intake passage by the EGR device, the amount of intake air, and the engine speed. That is, the higher the possibility of misfire occurrence, the earlier the fuel cut process can be started.

By the way, in an internal combustion engine having a plurality of cylinders, the downstream portion of the intake passage is configured to branch for each cylinder. When a passage portion of the intake passage that branches for each cylinder is a branch passage portion, the EGR device has a plurality of EGR ports connected to the plurality of branch passage portions. One aspect of a control device applied to a hybrid vehicle having such an internal combustion engine is provided with a blockage diagnosis section that diagnoses whether or not there is a blocked EGR port among the EGR ports. In this case, the judgment continuation time is made shorter when it is diagnosed that there is a blocked EGR port than when it is not diagnosed that there is a blocked EGR port.

If some of the EGR ports are blocked, the EGR gas will not be recirculated to the branch passage through the EGR ports. On the other hand, a large amount of EGR gas is recirculated to the branch passage from the EGR port that is not blocked. In other words, the ratio of the EGR gas to the gas introduced into the cylinder varies from cylinder to cylinder. In addition, misfires are likely to occur in cylinders in which the proportion of EGR gas is large.

In this regard, according to the above configuration, when it is diagnosed that there is a blocked EGR port, the determination duration is shorter than when it is not diagnosed that there is a blocked EGR port. be. Therefore, when there is a blocked EGR port, misfire is more likely to occur than when there is no blocked EGR port, so the fuel cut process can be started early.

In one aspect of the control device including the injection valve control unit, the injection valve control unit provides that the intake air amount is equal to or less than the determination intake air amount when the opening degree of the throttle valve is decreased by executing the rapid decrease process. First, air-fuel ratio rich processing is executed to control the fuel injection valve so that the air-fuel ratio becomes a value on the rich side.

According to the above configuration, when the opening degree of the throttle valve is decreased by executing the sudden decrease process, and the intake air amount is less than the determined intake air amount, the intake air amount becomes too small and misfire occurs in the internal combustion engine. Since it can be determined that there is a risk of occurrence, air-fuel ratio rich processing is executed. When the air-fuel ratio rich process is executed, the air-fuel ratio becomes richer than when the air-fuel ratio rich process is not executed. As a result, misfires are less likely to occur in the internal combustion engine.

In the air-fuel ratio rich process, the injection valve control unit shifts the air-fuel ratio to the rich side as the amount of EGR gas recirculated to the intake passage by the EGR device increases, and shifts the air-fuel ratio to the rich side as the amount of intake air decreases. The fuel injection valve may be controlled such that the higher the engine speed, the richer the air-fuel ratio becomes.

The greater the amount of EGR gas recirculated to the intake passage, the more likely misfires will occur in the internal combustion engine. Also, the smaller the amount of intake air, the more likely misfires will occur. Also, the higher the engine speed, the more likely misfires will occur. In this respect, according to the above configuration, the air-fuel ratio during the air-fuel ratio rich process can be set to a value corresponding to the amount of EGR gas recirculated to the intake passage by the EGR device, the amount of intake air, and the engine speed. That is, the higher the possibility of misfire occurrence, the greater the richness of the air-fuel ratio. Therefore, it is possible to enhance the effect of suppressing the occurrence of misfires during execution of the rapid decrease process.

1 is a diagram showing a functional configuration of a hybrid vehicle control device according to a first embodiment and a schematic configuration of a hybrid vehicle including the same control device; FIG. FIG. 2 is a diagram showing a schematic configuration of an internal combustion engine included in the hybrid vehicle; 4 is a flowchart for explaining a processing routine executed by a combustion determination section of the control device; 4 is a flowchart for explaining a processing routine executed by a motor control section of the control device; 4 is a flowchart for explaining a processing routine executed by a sudden drop processing section of the same control device; 4 is a flowchart for explaining a processing routine executed by an ignition timing adjustment section of the same control device; 4 is a flowchart for explaining a processing routine executed by an injection valve control section of the control device; 6 is a flowchart for explaining a processing routine executed by an injection valve control section of a control device according to a second embodiment;

(First embodiment)
A first embodiment of a control device for a hybrid vehicle will be described below with reference to FIGS. 1 to 7. FIG.
FIG. 1 shows a schematic configuration of a hybrid vehicle to which a control device 100 of this embodiment is applied. A hybrid vehicle includes an internal combustion engine 10 which is one of the power sources of the vehicle, a power distribution integration mechanism 40 connected to a crankshaft 18 of the internal combustion engine 10, and a first motor connected to the power distribution integration mechanism 40. and a generator 71 . The power distribution integration mechanism 40 is an example of a "power split mechanism." A second motor generator 72 is connected to the power distribution integration mechanism 40 via a reduction gear 50 , and a drive wheel 62 is connected via a speed reduction mechanism 60 and a differential 61 .

The power distribution integration mechanism 40 is a planetary gear mechanism, and has a sun gear 41 that is an external gear and a ring gear 42 that is coaxial with the sun gear 41 and is an internal gear. A plurality of pinion gears 43 that mesh with both the sun gear 41 and the ring gear 42 are arranged between the sun gear 41 and the ring gear 42 . Each pinion gear 43 is supported by a carrier 44 so as to freely rotate and revolve. A first motor generator 71 is connected to the sun gear 41 . The crankshaft 18 is connected to the carrier 44 . A ring gear shaft 45 is connected to the ring gear 42 , and both the reduction gear 50 and the speed reduction mechanism 60 are connected to the ring gear shaft 45 .

When the output torque of the internal combustion engine 10 is input to the carrier 44, the output torque is distributed to the sun gear 41 side and the ring gear 42 side. That is, by inputting the output torque of the internal combustion engine 10 to the first motor generator 71, the first motor generator 71 can generate electric power.

On the other hand, when the first motor generator 71 is caused to function as an electric motor, the output torque of the first motor generator 71 is input to the sun gear 41 . Then, the output torque of the first motor generator 71 input to the sun gear 41 is distributed to the carrier 44 side and the ring gear 42 side. By inputting the output torque of the first motor generator 71 to the crankshaft 18 via the carrier 44, the crankshaft 18 can be rotated.

The reduction gear 50 is a planetary gear mechanism, and has a sun gear 51 that is an external gear to which the second motor generator 72 is connected, and a ring gear 52 that is an internal gear coaxially arranged with the sun gear 51 . . A ring gear shaft 45 is connected to the ring gear 52 . A plurality of pinion gears 53 that mesh with both the sun gear 51 and the ring gear 52 are arranged between the sun gear 51 and the ring gear 52 . Each pinion gear 53 is rotatable but cannot revolve.

When decelerating the vehicle, the second motor generator 72 is caused to function as a generator, so that the vehicle can generate regenerative braking force corresponding to the amount of power generated by the second motor generator 72 . Further, when the second motor generator 72 functions as an electric motor, the output torque of the second motor generator 72 is input to the drive wheels 62 via the reduction gear 50, the ring gear shaft 45, the speed reduction mechanism 60 and the differential 61. . Thereby, the drive wheel 62 can be rotated. That is, the second motor generator 72 can also function as a power source of the vehicle.

The first motor generator 71 exchanges electric power with the battery 77 via the first inverter 75 . The second motor generator 72 exchanges electric power with the battery 77 via the second inverter 76 .

As shown in FIG. 2 , the internal combustion engine 10 has multiple cylinders 11 . Intake air is introduced into each cylinder 11 via an intake passage 12 . A throttle valve 13 is provided in the intake passage 12, and a portion downstream of the throttle valve 13 in the intake passage 12 branches into a plurality of branches. A passage portion of the intake passage 12 that branches for each cylinder 11 is referred to as a "branch passage portion 12A."

In each cylinder 11 , spark discharge from the ignition device 14 burns a mixture containing intake air introduced through the intake passage 12 and fuel injected from the fuel injection valve 15 . Exhaust gas generated in each cylinder 11 by combustion of the air-fuel mixture is discharged to the exhaust passage 16 . The exhaust passage 16 is provided with a three-way catalyst 17, which is an example of a catalyst having a function of purifying exhaust gas.

The internal combustion engine 10 includes an EGR device 20 that recirculates part of the exhaust gas flowing through the exhaust passage 16 to the intake passage 12 as EGR gas. The EGR device 20 has an EGR passage 21 connected to a portion of the exhaust passage 16 downstream of the three-way catalyst 17 and an EGR valve 22 provided in the EGR passage 21 . The EGR passage 21 is provided with a plurality of EGR ports 211 connected to each branch passage portion 12A. Therefore, when the EGR valve 22 is open, the EGR gas is recirculated to the branch passage portion 12A through the EGR port 211. At this time, the greater the degree of opening of the EGR valve 22, the greater the amount of EGR gas recirculated to the branch passage portion 12A. On the other hand, when the EGR valve 22 is closed, the recirculation of EGR gas to the branch passage portion 12A is stopped.

Next, the control device 100 will be described with reference to FIG.
Detection signals are input to the control device 100 from various sensors. A vehicle speed sensor 91, an air flow meter 92, a crank angle sensor 93, an air-fuel ratio sensor 94, and a water temperature sensor 95 can be cited as sensors. A vehicle speed sensor 91 detects a vehicle speed VS and outputs a signal corresponding to the vehicle speed VS as a detection signal. The airflow meter 92 detects an intake air amount GA, which is the amount of intake air flowing through the intake passage 12, and outputs a signal corresponding to the intake air amount GA as a detection signal. The crank angle sensor 93 outputs a signal corresponding to the engine rotation speed NE, which is the rotation speed of the crankshaft 18, as a detection signal. The air-fuel ratio sensor 94 detects the air-fuel ratio AF and outputs a signal corresponding to the air-fuel ratio AF as a detection signal. A water temperature sensor 95 detects a water temperature TWT, which is the temperature of cooling water circulating in the internal combustion engine 10, and outputs a signal corresponding to the water temperature TWT as a detection signal. The control device 100 controls the internal combustion engine 10 and the motor generators 71 and 72 based on detection signals from these various sensors 91-95.

The control device 100 has a motor control section 110 , a battery monitoring section 120 and an engine control section 130 .
Battery monitoring unit 120 monitors the state of battery 77 . For example, the battery monitoring unit 120 monitors the state of the battery 77 by monitoring the storage amount SOC of the battery 77 and the temperature TBT of the battery 77 .

The engine control unit 130 includes, as functional units for controlling the internal combustion engine 10, a combustion determination unit 131, a normal processing unit 132, a sudden drop processing unit 133, a guard setting unit 134, an ignition timing adjustment unit 135, and an injection valve control unit 136. and an obstruction diagnosis unit 137 .

The combustion determination unit 131 determines whether or not the air-fuel mixture is stably combusted in the cylinder 11 of the internal combustion engine 10 while the engine is running. The specific content of the determination process as to whether or not the air-fuel mixture is stably combusted will be described later.

The normal processing unit 132 executes normal processing for adjusting the throttle opening SL, which is the opening of the throttle valve 13, and the EGR opening REGR, which is the opening of the EGR valve 22, when the engine is running. do. In the present embodiment, the normal processing unit 132 executes normal processing when sudden drop processing, which will be described later, is not executed. In normal processing, the normal processing unit 132 adjusts the throttle opening SL and the EGR opening REGR according to the required engine output PEQ, which is the required output for the internal combustion engine 10 . For example, in normal processing, the normal processing unit 132 increases the throttle opening SL and the EGR opening REGR as the required engine output PEQ increases.

The rapid decrease processing unit 133 controls the rate of decrease of the EGR opening REGR to be higher than the rate of decrease of the throttle opening SL on the condition that the conditions for starting the rapid decrease process are satisfied when the required engine output PEQ decreases. A rapid decrease process is started to decrease the throttle opening SL and the EGR opening REGR so that The details of the condition for starting the sudden drop process and the details of the sudden drop process will be described later.

Even when the requested engine output PEQ decreases, if the conditions for starting the rapid decrease process are not satisfied, the normal process is executed by the normal processing unit 132 to adjust the throttle opening SL and the EGR opening REGR.

A guard setting unit 134 sets a lower limit guard PELm of the engine output PE, which is the output of the internal combustion engine 10 . The lower limit guard PELm is used when executing the sudden drop process. That is, the engine output PE does not fall below the lower limit guard PELm during execution of the rapid decrease process.

Guard setting unit 134 sets a value corresponding to EGR rate Y as lower limit guard PELm. The EGR rate Y is a value obtained by dividing the amount of EGR gas recirculated to the intake passage 12 by the EGR device 20 by the intake air amount GA. The higher the EGR rate Y, the smaller the ratio of the intake air to the gas introduced into the cylinder 11 . Therefore, if the lower limit guard PELm is made small even though the EGR rate Y is high, the amount of intake air introduced into the cylinder 11 becomes too small, and misfire may occur in the internal combustion engine 10 . Therefore, in the present embodiment, the guard setting unit 134 sets the lower limit guard PELm such that the higher the EGR rate Y, the larger the lower limit guard PELm.

The ignition timing adjustment unit 135 adjusts the ignition timing TINJ. In this embodiment, the ignition timing adjusting section 135 may execute the ignition timing retarding process while the rapid decrease process is being executed. The ignition timing retardation process is a process for suppressing an increase in the engine output PE by retarding the ignition timing TINJ more than when the ignition timing retardation process is not executed. The conditions for executing the ignition timing retarding process and the specific contents of the ignition timing retarding process will be described later.

The injection valve control section 136 controls each fuel injection valve 15 . In this embodiment, the injection valve control unit 136 may execute a fuel cut process to stop fuel injection of each fuel injection valve 15 while the sudden drop process is being executed. Conditions for starting and ending the fuel cut process will be described later.

The blockage diagnosis unit 137 diagnoses whether or not there is a blocked EGR port 211 among the plurality of EGR ports connected to the EGR passage 21 .
Under the condition that the EGR valve 22 is open, if all the EGR ports 211 are not closed, the amount of EGR gas introduced into each cylinder 11 is substantially the same. That is, the difference in the EGR rate Y for each cylinder 11 is small.

On the other hand, when only some of the EGR ports 211 are blocked, little EGR gas is introduced into the cylinders 11 corresponding to the blocked EGR ports 211 . EGR gas is introduced into the cylinders 11 corresponding to the remaining EGR ports 211 . That is, among the plurality of cylinders 11, there are cylinders 11 with a low EGR rate Y and cylinders 11 with a high EGR rate Y. Therefore, when the required engine output PEQ is held at a constant value, the amount of variation in the engine rotation speed NE tends to increase compared to when there is no blocked EGR port 211 .

Therefore, in the present embodiment, the blockage diagnosis unit 137 detects fluctuations in the engine speed NE when the EGR valve 22 is closed and fluctuations in the engine speed NE when the EGR valve 22 is open. is compared to diagnose whether or not there is a blocked EGR port 211 . For example, when the difference between the variation in the engine rotation speed NE when the EGR valve 22 is closed and the variation in the engine rotation speed NE when the EGR valve 22 is open is small, the blockage diagnosis unit 137 , make a diagnosis that there is no blocked EGR port 211 . On the other hand, when there is a large divergence between the fluctuations in the engine speed NE when the EGR valve 22 is closed and the fluctuations in the engine speed NE when the EGR valve 22 is open, the blockage diagnosis unit 137 , make a diagnosis that there is a blocked EGR port 211 .

Motor control unit 110 drives first motor generator 71 by controlling first inverter 75 . Motor control unit 110 also drives second motor generator 72 by controlling second inverter 76 .

In the present embodiment, the motor control unit 110 may execute power generation processing for causing the first motor generator 71 to generate power when the rapid decrease processing is being executed. Further, the motor control unit 110 may execute the push-down process or the push-up process even during engine operation if the sudden drop process is not executed. The push-down process is a process of causing the first motor generator 71 to output the first motor torque TQM1, which is torque in the direction in which the load applied to the internal combustion engine 10 increases. The push-up process is a process of causing the first motor generator 71 to output the second motor torque TQM2, which is torque in the direction opposite to the direction of the first motor torque TQM1. The specific contents of the motor control unit 110 will be described later.

Next, a processing routine executed by the combustion determination unit 131 will be described with reference to FIG. This processing routine is a routine for determining whether or not the air-fuel mixture in the cylinder 11 is stably combusted. This processing routine is repeatedly executed when the fuel cut processing is not executed while the engine is running.

In the first step S11 of this processing routine, it is determined whether or not the engine speed NE is equal to or higher than the determination engine speed NETh. The engine rotation speed when the requested engine output PEQ is equal to or less than the specified value is set as the determination engine rotation speed NETh. That is, in a situation where the engine is running and the fuel cut process is not being executed, normally, the engine speed NE does not become less than the determination engine speed NETh. In other words, when the engine speed NE is less than the determination engine speed NETh, there is a possibility that the air-fuel mixture in the cylinder 11 is not stably combusted. In step S11, if the engine speed NE is less than the determination engine speed NETh (NO), the process proceeds to step S17, which will be described later. On the other hand, when the engine speed NE is equal to or higher than the determination engine speed NETh (S11: YES), the process proceeds to the next step S12.

In step S12, it is determined whether or not the water temperature TWT is equal to or higher than the determination water temperature TWTTh. The determination water temperature TWTTh is set as a criterion for determining whether or not the warm-up operation of the internal combustion engine 10 is completed. If the warm-up operation has not yet been completed, there is a possibility that the air-fuel mixture in the cylinder 11 is not burning stably. In step S12, if the water temperature TWT is less than the determination water temperature TWTTh (NO), it can be determined that the warm-up operation has not been completed, so the process proceeds to step S17. On the other hand, when the water temperature TWT is equal to or higher than the determination water temperature TWTTh (S12: YES), the process proceeds to the next step S13.

At step S13, it is determined whether or not the engine has been started. For example, when the internal combustion engine 10 has completely exploded, it is determined that the engine has been started. If the engine starting has not been completed, there is a possibility that the air-fuel mixture in the cylinder 11 is not stably combusted. In step S13, if engine starting has not been completed (NO), the process proceeds to step S17. On the other hand, if the engine has been started (S13: YES), the process proceeds to the next step S14.

In step S14, it is determined whether or not the fuel injected from the fuel injection valve 15 is highly combustible. During engine operation, fuel injection is performed based on a basic injection amount corresponding to the required engine output PEQ and a feedback control amount calculated by feedback control using the difference between the air-fuel ratio AF and the target air-fuel ratio AFTr as inputs. quantity is determined. The fuel injection amount is derived so as to increase as the base injection amount increases. The fuel injection amount is derived so as to increase as the feedback control amount increases. An upper limit is set for the feedback control amount. Therefore, the feedback control amount that exceeds the upper limit is not calculated by the feedback control.

Here, when fuel with low combustibility is injected from the fuel injection valve 15, the absolute value of the deviation between the air-fuel ratio AF and the target air-fuel ratio AFTr tends to increase. That is, the absolute value of the feedback control amount tends to increase. At this time, when the state in which the absolute value of the feedback control amount is equal to the upper limit continues for a predetermined time or longer, it can be determined that fuel with low combustibility is being injected from the fuel injection valve 15 . Then, when fuel with low combustibility is injected from the fuel injection valve 15, there is a possibility that the air-fuel mixture in the cylinder 11 is not stably combusted.

Therefore, when it is not determined in step S14 that the fuel injected from the fuel injection valve 15 is highly combustible fuel (NO), the process proceeds to step S17. On the other hand, when it is determined that the fuel injected from the fuel injection valve 15 is highly combustible fuel (S14: YES), the process proceeds to the next step S15.

At step S15, it is determined whether or not the valve timing adjustment device provided in the internal combustion engine 10 is operating normally. The valve timing adjustment device is a device that adjusts the opening/closing timing of the intake valves of the internal combustion engine 10 . The valve timing control device is also called "VVT". When the valve timing adjustment device is in the fail-safe state, it is not determined that it is operating normally. On the other hand, if it is not in fail-safe mode, it is determined that it is operating normally. If it is not determined in step S15 that the device is operating normally (NO), the process proceeds to step S17. On the other hand, if it is determined that it is operating normally (S15: YES), the process proceeds to the next step S16.

In step S16, the stable combustion flag FLG1 is set to ON. That is, if all of the determinations in steps S11 to S15 are "YES", it is determined that the air-fuel mixture in the cylinder 11 is stably combusted. Then, this processing routine is temporarily terminated.

In step S17, the stable combustion flag FLG1 is set to OFF. That is, if the determination in any one of steps S11 to S15 is "NO", it is not determined that the air-fuel mixture is stably combusted in the cylinder 11. Then, this processing routine is temporarily terminated.

Next, a processing routine executed by the motor control unit 110 will be described with reference to FIG. This processing routine is repeatedly executed while the engine is running.
In this processing routine, at the first step S21, it is determined whether or not the sudden drop processing is being executed by the sudden drop processing unit 133 . If the rapid decrease process is not being executed (S21: NO), the process proceeds to the next step S22. In step S22, it is determined whether or not the vehicle speed VS is less than the determination vehicle speed VSTh. The higher the vehicle speed VS, the louder the running sound of the vehicle. A determination vehicle speed VSTh is set as a criterion for determining whether or not the running noise is loud. That is, when the vehicle speed VS is less than the determination vehicle speed VSTh, the running noise is small. In step S22, if the vehicle speed VS is equal to or higher than the determination vehicle speed VSTh (NO), it can be determined that the running sound of the vehicle is loud, so this processing routine is temporarily terminated. That is, neither the push-down process nor the push-up process is executed. On the other hand, when the vehicle speed VS is less than the determination vehicle speed VSTh (S22: YES), the process proceeds to the next step S23.

In step S23, it is determined whether or not the stable combustion flag FLG1 is set to ON. If the stable combustion flag FLG1 is set to ON (S23: YES), the process proceeds to the next step S24. Then, in step S24, a depression process is executed. That is, in this embodiment, when it is determined that the air-fuel mixture is stably combusted in the cylinder 11, the push-down process is executed. Then, when the push-down process is executed, this process routine is terminated.

As described above, the first motor torque TQM1 is output from the first motor generator 71 in the depression process. In the power distribution integration mechanism 40 , the sun gear 41 is a gear connected to the first motor generator 71 and the pinion gear 43 is a gear connected to the internal combustion engine 10 . Assuming that the torque input from the internal combustion engine 10 to the pinion gear 43 while the engine is running is positive torque, when the first motor torque TQM1 is input to the sun gear 41, the sun gear 41 to the pinion gear 43 The direction of the input torque is opposite to the positive torque. Therefore, when the push-down process is being executed, the teeth of the sun gear 41 are pressed against the teeth of the pinion gear 43 from the rotation direction side of the pinion gear 43 . As a result, the generation of backlash in the power distribution integration mechanism 40 is suppressed, and in turn, the generation of vibration and abnormal noise caused by the backlash is suppressed.

On the other hand, in step S23, when the stable combustion flag FLG1 is set to OFF (NO), the process proceeds to the next step S25. In step S25, push-up processing is performed. That is, in the present embodiment, the push-up process is executed when it is not determined that the air-fuel mixture is stably combusted in the cylinder 11 . Then, when the push-up process is executed, this process routine is terminated.

As described above, the second motor torque TQM2 is output from the first motor generator 71 when the push-up process is being performed. In the power distribution integration mechanism 40 , the sun gear 41 is a gear connected to the first motor generator 71 and the pinion gear 43 is a gear connected to the internal combustion engine 10 . Assuming that the torque input from the internal combustion engine 10 to the pinion gear 43 while the engine is running is positive torque, when the second motor torque TQM2 is input to the sun gear 41, the sun gear 41 to the pinion gear 43 The direction of the input torque is the same direction as the positive torque. Therefore, when the push-up process is being performed, the teeth of the sun gear 41 are pressed against the teeth of the pinion gear 43 from the side opposite to the rotation direction of the pinion gear 43 . As a result, the generation of backlash in the power distribution integration mechanism 40 is suppressed, and in turn, the generation of vibration and abnormal noise caused by the backlash is suppressed.

On the other hand, in step S21, if the rapid decrease process is being performed (YES), the process proceeds to next step S26. In step S26, it is determined whether or not the state of charge SOC of the battery 77 is less than the determination state of charge SOCTh. A determination storage amount SOCTh is set as a criterion for determining whether or not the state of the battery 77 is such that a further increase in the storage amount SOC is undesirable. If the state of charge SOC is equal to or greater than the determined state of charge SOCTh, further increase in the state of charge SOC is undesirable. Therefore, in step S26, when the amount of stored electricity SOC is equal to or greater than the determined amount of stored electricity SOCTh (NO), this processing routine is temporarily terminated without executing the power generation processing, which is the processing of step S27. On the other hand, when the stored electricity amount SOC is less than the determined stored electricity amount SOCTh (S26: YES), the process proceeds to the next step S27. In step S27, power generation processing is executed. Once the power generation process is executed, this process routine is terminated.

When the lower guard PELm is larger than the required engine output PEQ under the condition that the rapid decrease process is being executed, the actual engine output PE may become larger than the required engine output PEQ. If the actual engine output PE is greater than the required engine output PEQ, it becomes difficult for the vehicle speed VS to decrease. Therefore, in the power generation process, when the lower limit guard PELm is greater than the requested engine output PEQ, the first motor generator 71 generates power in accordance with the difference between the lower limit guard PELm and the requested engine output PEQ. Motor generator 71 is driven. As a result, an output corresponding to the difference between the actual engine output PE and the requested engine output PEQ is consumed by the power generation of the first motor generator 71 .

If the lower limit guard PELm is equal to or less than the required engine output PEQ even during the execution of the rapid decrease process, the power generation process performs the first motor generator 71 so that the power generation amount of the first motor generator 71 becomes "0 (zero)". Motor generator 71 is driven.

Next, with reference to FIG. 5, a processing routine executed by the sudden drop processing unit 133 will be described. This processing routine is repeatedly executed when the fuel cut processing is not being executed while the engine is running.

In the first step S31 of this processing routine, it is determined whether or not the reduction amount ΔPEQ of the requested engine output PEQ is equal to or greater than the judgment reduction amount ΔPEQTh. The determination decrease amount ΔPEQTh is a criterion for determining whether or not the requested engine output PEQ has decreased significantly.

In general, when the requested engine power PEQ is decreased, the throttle opening SL is also decreased. Furthermore, the EGR opening REGR is also reduced as the throttle opening SL decreases. At this time, if the responsiveness of the EGR valve 22 is lower than the responsiveness of the throttle valve 13, the EGR rate Y will increase due to the response delay of the EGR valve 22. If the EGR rate Y becomes extremely high while the required engine output PEQ is small, the proportion of the intake air in the gas introduced into the cylinder 11 becomes extremely small, and misfire may occur in the internal combustion engine 10. be.

If the decrease amount ΔPEQ is equal to or greater than the determination decrease amount ΔPEQTh, the required engine output PEQ has decreased significantly, so if normal processing is executed, the ratio of the intake air to the gas introduced into the cylinder 11 will be extremely small. misfire may occur in the internal combustion engine 10. On the other hand, if the decrease amount ΔPEQ is less than the determination decrease amount ΔPEQTh, the required engine output PEQ has not decreased, or the required engine output PEQ has decreased but the decrease amount ΔPEQ is not so large. Therefore, even if normal processing is executed, the ratio of the intake air to the gas introduced into the cylinder 11 does not become extremely small, and misfire does not occur in the internal combustion engine 10 .

Therefore, in step S31, when the decrease amount ΔPEQ is equal to or greater than the determination decrease amount ΔPEQTh (YES), the rapid decrease process is started. That is, the condition for starting the rapid decrease process is that the decrease amount ΔPEQ is equal to or greater than the determination decrease amount ΔPEQTh. On the other hand, if the decrease amount ΔPEQ is less than the determination decrease amount ΔPEQTh (S31: NO), the process proceeds to step S36, which will be described later.

In the rapid decrease process, the target engine output PETr is set in the first step S32. That is, the larger one of the required engine output PEQ and the lower guard PELm is set as the target engine output PETr. A lower limit guard PELm used for setting the target engine output PETr is set by the guard setting unit 134 . Subsequently, in step S33, a value corresponding to the target engine output PETr is set as the target throttle opening XSL, which is the target of the throttle opening SL. That is, the target throttle opening XSL decreases as the target engine output PETr decreases. Therefore, since the lower limit guard PELm is larger than the required engine output PEQ, when the target engine output PETr is larger than the required engine output PEQ, the target throttle opening XSL is larger than the opening according to the required engine output PEQ. Become. That is, the reduction of the target throttle opening XSL is restricted.

Then, in the next step S34, a value corresponding to the required engine output PEQ is set as the target EGR opening degree XEGR, which is the target of the EGR opening degree REGR. That is, the target EGR opening XEGR becomes smaller as the required engine output PEQ becomes smaller. The target throttle opening XSL is set to a value corresponding to the target engine output PETr, while the target EGR opening XEGR is set to a value corresponding to the required engine output PEQ. That is, in the rapid decrease process, reduction of the target EGR opening XEGR is executed with priority over reduction of the target throttle opening XSL.

Subsequently, in step S35, the throttle valve 13 is controlled based on the target throttle opening XSL, and the EGR valve 22 is controlled based on the target EGR opening XEGR. As a result, the throttle opening SL and the EGR opening REGR are decreased such that the EGR opening REGR decreases faster than the throttle opening SL. When the rapid decrease process is executed in this manner, the present process routine is terminated.

In step S36, it is determined whether or not the sudden drop process is being executed. If the rapid decrease process is not being executed (S36: NO), this process routine is temporarily terminated. In this case, the throttle opening SL and the EGR opening REGR are each adjusted through execution of normal processing. On the other hand, in step S36, if the rapid decrease process is being performed (YES), the process proceeds to the next step S37.

In step S37, it is determined whether or not a termination condition for the rapid decrease process is satisfied. That is, when it can be determined that the EGR opening REGR has reached the opening corresponding to the required engine output PEQ, it is determined that the end condition is met. Even if the target EGR opening XEGR is changed according to the change in the required engine output PEQ, the change in the EGR opening REGR is delayed with respect to the change in the required engine output PEQ. Therefore, the EGR opening REGR is estimated taking into account the delay.

For example, when the accelerator operation by the driver is canceled and the minimum value that can be generated as the engine output PE during engine operation is set as the required engine output PEQ, the EGR opening REGR corresponding to the required engine output PEQ is "0 (zero)" is set. Therefore, when the accelerator operation is canceled, it is determined that the termination condition of the rapid decrease process is satisfied when the EGR valve 22 is completely closed.

If it is not determined in step S37 that the end condition is satisfied (NO), the process proceeds to step S32. That is, the sudden drop process is continued. On the other hand, if it is determined that the end condition is satisfied (S37: YES), the rapid decrease process is ended, and this process routine is once ended. After this, the throttle opening SL and the EGR opening REGR are adjusted through execution of normal processing.

Next, a processing routine executed by the ignition timing adjustment section 135 will be described with reference to FIG. This processing routine is repeatedly executed when the fuel cut processing is not executed while the engine is running.

In this processing routine, at the first step S41, it is determined whether or not the rapid decrease processing is being executed. If the sudden decrease process has not been executed (S41: NO), the present process routine is temporarily ended without executing the ignition timing retardation process. On the other hand, if the rapid decrease process is being executed (S41: YES), the process proceeds to the next step S42.

In step S42, it is determined whether or not the state of charge SOC of the battery 77 is greater than or equal to the determination state of charge SOCTh. If the stored electricity amount SOC is less than the determined stored electricity amount SOCTh (S42: NO), the power generation process is being executed, so this processing routine is temporarily terminated. That is, the ignition timing retarding process is not executed. On the other hand, if the stored electricity amount SOC is equal to or greater than the determined stored electricity amount SOCTh (S42: YES), the process proceeds to the next step S43 because the power generation process is not being performed even though the rapid decrease process is being performed.

In step S43, ignition timing retardation processing is executed. The more the ignition timing TINJ is retarded, the smaller the engine output PE can be. When the rapid decrease process is being executed and the target engine output PETr is greater than the required engine output PEQ, the actual engine output PE becomes greater than the required engine output PEQ. Therefore, in the ignition timing retarding process, the ignition timing TINJ is retarded by an amount corresponding to the difference between the target engine output PETr and the required engine output PEQ, compared to when the ignition timing retarding process is not executed. That is, the greater the difference, the greater the retardation amount of the ignition timing TINJ. Then, this processing routine is temporarily terminated.

Next, a processing routine executed by the injection valve control section 136 will be described with reference to FIG. This processing routine is repeatedly executed while the engine is running.
In this processing routine, at the first step S51, it is determined whether or not the sudden drop processing is being executed. If the rapid decrease process is being executed (S51: YES), the process proceeds to the next step S52. In step S52, it is determined whether or not the intake air amount GA is equal to or less than the determination intake air amount GATh.

When the throttle valve 13 has deposits, the intake air amount GA may become smaller than the amount corresponding to the throttle opening SL. If the intake air amount GA is excessively small, the amount of fuel supplied to the cylinder 11 will also be small, which may cause misfiring in the internal combustion engine 10 . Therefore, a determination intake air amount GATh is set as a criterion for determining whether or not there is a risk of misfire occurring due to a small intake air amount GA.

In step S52, if the intake air amount GA is greater than the determination intake air amount GATh (NO), this processing routine is temporarily terminated. In this case, execution of the rapid decrease process is continued. On the other hand, if the intake air amount GA is equal to or less than the determined intake air amount GATh (S52: YES), the process proceeds to the next step S53. In step S53, it is determined whether or not the state in which the intake air amount GA is equal to or less than the determination intake air amount GATh continues for the determination continuation time TMTh or longer. If the duration of the state in which the intake air amount GA is equal to or less than the determination intake air amount GATh is less than the determination continuation time TMTh (S53: NO), it can be determined that a misfire has not yet occurred in the internal combustion engine 10. Therefore, this processing routine is executed. once terminated. On the other hand, if the duration of the state in which the intake air amount GA is equal to or less than the determination intake air amount GATh is equal to or greater than the determination continuation time TMTh (S53: YES), it can be determined that misfire may occur in the internal combustion engine 10. The process proceeds to the next step S54.

It should be noted that misfires are more likely to occur as the amount of EGR gas recirculated to the intake passage 12 increases. In addition, the smaller the intake air amount GA, the more likely misfire occurs. Also, the higher the engine rotation speed NE, the more likely misfiring occurs. In the present embodiment, the higher the possibility of a misfire occurring in the internal combustion engine 10, the shorter the determination continuation time TMTh is set. That is, the larger the amount of EGR gas recirculated to the intake passage 12 by the EGR device 20, the shorter the determination continuation time TMTh is set. Further, as the determination continuation time TMTh, a shorter time is set as the intake air amount GA is smaller. Further, the judgment continuation time TMTh is set to a shorter time as the engine rotation speed NE is higher.

If some of the EGR ports 211 among the plurality of EGR ports 211 are blocked, the EGR rate Y will be higher than the EGR rate Y in the other cylinders 11 when the required engine output PEQ is greatly reduced. A misfire may occur in the cylinder 11 . Therefore, when the obstruction diagnosis unit 137 diagnoses that there is a blocked EGR port 211, the determination duration time TMTh is longer than when it is not diagnosed that there is a blocked EGR port 211. A short time is set.

In step S54, fuel cut processing is executed. Then, this processing routine is temporarily terminated.
When the fuel cut process is started because the intake air amount GA has become equal to or less than the determination intake air amount GATh due to the execution of the sudden decrease process, the process routine shown in FIG. 5 is not executed. That is, the sudden drop process is no longer executed. Then, the throttle opening SL and the EGR opening REGR are adjusted by normal processing. Further, when the power generation process is being executed in conjunction with the execution of the rapid decrease process, the power generation process is no longer executed when the rapid decrease process is terminated due to the execution of the fuel cut process. Further, when the ignition timing retarding process is executed along with the execution of the rapid decrease process, the ignition timing retarding process is not executed when the sudden decrease process is terminated due to the execution of the fuel cut process.

On the other hand, in step S51, if the rapid decrease process is not executed (NO), the process proceeds to the next step S55. At step S55, it is determined whether or not the fuel cut process is being executed. If the fuel cut process is not being executed (S55: NO), this process routine is temporarily terminated. On the other hand, if the fuel cut process is being executed (S55: YES), the process proceeds to the next step S56.

In step S56, it is determined whether or not the EGR opening REGR has reached the opening corresponding to the requested engine output PEQ. If it is not determined that the EGR opening REGR has reached the opening corresponding to the requested engine output PEQ (S56: NO), it is determined that the EGR opening REGR is still larger than the opening corresponding to the requested engine output PEQ. and the process proceeds to step S54. That is, the execution of the fuel cut process is continued.

On the other hand, if it is determined in step S56 that the EGR opening REGR has reached the opening corresponding to the requested engine output PEQ (YES), the process proceeds to the next step S57. In step S57, the fuel injection of the fuel injection valve 15 is resumed. That is, the fuel cut process ends. After that, this processing routine is temporarily terminated.

The action and effect of this embodiment will be described.
(1) If it is not determined that the air-fuel mixture is stably combusted in the cylinder 11 in a situation where the rapid decrease process is not executed, the push-down process is not executed. Therefore, when the combustion of the air-fuel mixture in the cylinder 11 is unstable, it is possible to suppress the occurrence of a misfire in the internal combustion engine 10 due to the execution of the push-down process. In this embodiment, when it is not determined that the air-fuel mixture is stably combusted in the cylinder 11, push-up processing is executed instead of push-down processing. By executing the push-up process, the load applied to the internal combustion engine 10 by driving the first motor generator 71 can be reduced. The fuel efficiency of the internal combustion engine 10 can be improved by operating the engine with the load reduced in this manner. In addition, compared to the case where the push-up process is not executed, rattling in the power distribution and integration mechanism 40 can be suppressed, and vibration and abnormal noise caused by the rattling in the power distribution and integration mechanism 40 can be suppressed. Its occurrence can be suppressed.

(2) On the other hand, when it is determined that the air-fuel mixture is stably combusted in the cylinder 11 under the condition that the sudden decrease process is not executed, the push-down process is executed. Therefore, rattling in the power distribution and integration mechanism 40 can be suppressed, and in turn, vibration and abnormal noise caused by the rattling in the power distribution and integration mechanism 40 can be suppressed.

(3) When the running noise is loud, even if rattling occurs in the power distribution integration mechanism 40, the occupants of the vehicle are less likely to feel uncomfortable due to the vibration and noise caused by the rattling. Therefore, in the present embodiment, when the vehicle speed VS is equal to or higher than the determination vehicle speed VSTh, it is determined that the air-fuel mixture is stably combusted in the cylinder 11 because the running noise generated when the vehicle is running is large. Also, the push-down process is not executed. Since the opportunity to execute the push-down process can be reduced in this way, deterioration of the fuel consumption of the internal combustion engine 10 can be suppressed.

(4) When the reduction amount ΔPEQ of the required engine output is equal to or greater than the determination reduction amount ΔPEQTh, the intake air amount GA is greatly reduced, so that the ratio of the intake air to the gas introduced into the cylinder 11 is small. Prone. Therefore, when the decrease amount ΔPEQ is equal to or greater than the determination decrease amount ΔPEQTh, the throttle opening SL and EGR are adjusted so that the decrease speed of the EGR opening REGR becomes higher than the decrease speed of the throttle opening SL by executing the rapid decrease process. The degree of opening REGR is decreased. By decreasing the EGR opening degree REGR with priority over the throttle opening degree SL in this way, the amount of EGR gas recirculated to the intake passage 12 is reduced with respect to the intake air reduction caused by the decrease in the throttle opening degree SL. delay is suppressed. As a result, it is possible to prevent the intake air from becoming too small in the gas introduced into the cylinder 11, thereby preventing misfires in the internal combustion engine 10 when the required engine output PEQ is reduced. can.

(5) In the rapid decrease process, when the lower limit guard PELm is larger than the required engine output PEQ, the target throttle opening XSL is set to the opening corresponding to the lower limit guard PELm. As a result, a decrease in the throttle opening SL is restricted, and a decrease in the intake air amount GA is suppressed. Therefore, it is possible to prevent the intake air from taking up too little of the gas introduced into the cylinder 11 . That is, the occurrence of misfires in the internal combustion engine 10 can be suppressed. Then, by executing the power generation process when the lower limit guard PELm is greater than the requested engine output PEQ, the first motor generator is configured so that the power generation amount corresponds to the difference between the lower limit guard PELm and the requested engine output PEQ. 71 is controlled. As a result, deterioration in the controllability of the torque transmitted to the drive wheels 62 of the vehicle can be suppressed.

(6) The lower limit guard PELm is set to decrease as the EGR rate Y decreases. That is, when the EGR rate Y is high, the lower limit guard PELm is large, so the intake air amount GA is less likely to decrease. As a result, it is possible to prevent the intake air from taking up too little of the gas introduced into the cylinder 11 . As a result, the occurrence of misfires in the internal combustion engine 10 can be suppressed.

On the other hand, when the EGR rate Y decreases due to the decrease in the EGR opening REGR, the lower limit guard PELm decreases. When the lower limit guard PELm is decreased in this manner, the throttle opening SL is also decreased. As a result, the engine output PE can be reduced, and the deviation between the engine output PE and the required engine output PEQ can be reduced.

(7) When the state of charge SOC of the battery 77 is less than the determination state of charge SOCTh during execution of the rapid decrease process, the power generation process is executed. On the other hand, when the stored electricity amount SOC is equal to or greater than the determined stored electricity amount SOCTh, the ignition timing retarding process is executed instead of the power generation process. By retarding the ignition timing TINJ by executing the ignition timing retarding process, the deviation between the engine output PE and the required engine output PEQ is suppressed. As a result, deterioration in the controllability of the torque transmitted to the drive wheels 62 of the vehicle can be suppressed without executing the power generation process.

(8) When the intake air amount GA is less than the determined intake air amount GATh, the intake air amount GA may become too small and misfire may occur in the internal combustion engine 10 . Therefore, when the intake air amount GA becomes less than the determination intake air amount GATh when the throttle opening degree SL is decreased by executing the rapid decrease process, it is determined that the intake air amount GA is less than the determination intake air amount GATh. On the condition that the fuel has continued for the duration time TMTh or more, the rapid decrease process is terminated and the fuel cut process is started. Since fuel injection is stopped when the fuel cut process is executed, unburned fuel does not reach the three-way catalyst 17 . As a result, it is possible to prevent the temperature of the three-way catalyst 17 from becoming too high.

(9) It should be noted that the higher the possibility of a misfire occurring in the internal combustion engine 10, the shorter the determination continuation time TMTh is set. By varying the determination continuation time TMTh in this way, the higher the possibility of misfire occurrence, the earlier the fuel cut process can be started.

(Second embodiment)
Next, a second embodiment of the hybrid vehicle control device will be described with reference to FIG. In this embodiment, the processing contents of the injection valve control section 136 are different from those in the first embodiment. In the following description, the parts that are different from the first embodiment will be mainly described, and the same reference numerals will be given to members that are the same as or correspond to those of the first embodiment, and redundant description will be omitted. shall be

A processing routine executed by the injection valve control unit 136 will be described with reference to FIG. This processing routine is repeatedly executed while the engine is running.
In this processing routine, in the first step S61, it is determined whether or not the sudden drop processing is being executed by the sudden drop processing unit 133 . If the sudden drop process is being executed (S61: YES), the process proceeds to the next step S62. In step S62, similarly to step S52, it is determined whether or not the intake air amount GA is equal to or less than the determination intake air amount GATh.

In step S62, if the intake air amount GA is greater than the determined intake air amount GATh (NO), this processing routine is temporarily terminated. In this case, execution of the rapid decrease process is continued. On the other hand, if the intake air amount GA is equal to or less than the determined intake air amount GATh (S62: YES), the process proceeds to the next step S63. In step S63, similarly to step S53, it is determined whether or not the state in which the intake air amount GA is equal to or less than the determination intake air amount GATh continues for the determination continuation time TMTh or longer. If the duration of the state in which the intake air amount GA is equal to or less than the determination intake air amount GATh is less than the determination duration TMTh (S63: NO), it can be determined that a misfire has not yet occurred in the internal combustion engine 10. Therefore, this processing routine is executed. once terminated. On the other hand, if the duration of the state in which the intake air amount GA is equal to or less than the determination intake air amount GATh is equal to or greater than the determination continuation time TMTh (S63: YES), it can be determined that a misfire may occur in the internal combustion engine 10. The process proceeds to the next step S64.

In step S64, air-fuel ratio enrichment processing is executed. In the air-fuel ratio enrichment process, an air-fuel ratio richer than the stoichiometric air-fuel ratio AFSt is set as the target air-fuel ratio AFTr, which is the target of the air-fuel ratio AF. Then, air-fuel ratio control based on the target air-fuel ratio AFTr is performed. As a result, the air-fuel ratio AF can be made richer than the stoichiometric air-fuel ratio AFSt. Then, this processing routine is temporarily terminated.

Here, misfiring is more likely to occur as the amount of EGR gas recirculated to the intake passage 12 increases. In addition, the smaller the intake air amount GA, the more likely misfire occurs. Also, the higher the engine rotation speed NE, the more likely misfiring occurs. Within a predetermined air-fuel ratio range including the stoichiometric air-fuel ratio AFSt, misfires in the internal combustion engine 10 are less likely to occur as the air-fuel ratio AF is set to a richer value.

Therefore, in the air-fuel ratio enrichment process, the target air-fuel ratio AFTr is set such that the difference between the target air-fuel ratio AFTr and the stoichiometric air-fuel ratio AFSt increases as the possibility of misfire occurring in the internal combustion engine 10 increases. That is, as the target air-fuel ratio AFTr, an air-fuel ratio on the richer side is set as the amount of EGR gas recirculated to the intake passage by the EGR device 20 increases. Further, as the target air-fuel ratio AFTr, an air-fuel ratio on the richer side is set as the intake air amount GA decreases. As the target air-fuel ratio AFTr, an air-fuel ratio on the richer side is set as the engine speed NE increases.

Note that when the air-fuel ratio enrichment process is started because the intake air amount GA has become equal to or less than the determination intake air amount GATh due to the execution of the rapid decrease process, the process routine shown in FIG. 5 is not executed. That is, the sudden drop process is no longer executed. Then, the throttle opening SL and the EGR opening REGR are adjusted by normal processing. Further, when the power generation process is being executed in conjunction with the execution of the air-fuel ratio enrichment process, the power generation process is no longer executed when the rapid decrease process is terminated due to the execution of the air-fuel ratio enrichment process. Further, when the ignition timing retarding process has been executed along with the execution of the rapid decrease process, the ignition timing retarding process is executed when the sudden decrease process is terminated due to the execution of the air-fuel ratio enriching process. Gone.

On the other hand, in step S61, if the rapid decrease process is not executed (NO), the process proceeds to the next step S65. At step S65, it is determined whether or not the air-fuel ratio enrichment process is being executed. If the air-fuel ratio enrichment process is not being executed (S65: NO), this process routine is temporarily terminated. On the other hand, if the air-fuel ratio enrichment process is being executed (S65: YES), the process proceeds to the next step S66.

In step S66, it is determined whether or not the EGR opening REGR has reached the opening corresponding to the requested engine output PEQ. If it is not determined that the EGR opening REGR has reached the opening corresponding to the requested engine output PEQ (S66: NO), it is determined that the EGR opening REGR is still larger than the opening corresponding to the requested engine output PEQ. and the process proceeds to step S64. That is, the execution of the air-fuel ratio enrichment process is continued.

On the other hand, if it is determined in step S66 that the EGR opening REGR has reached the opening corresponding to the requested engine output PEQ (YES), the process proceeds to the next step S67. In step S67, the theoretical air-fuel ratio AFSt is set as the target air-fuel ratio AFTr. That is, the air-fuel ratio enrichment process is ended. After that, this processing routine is temporarily terminated.

In this embodiment, in addition to the effects equivalent to the above (1) to (7), the following effects can be obtained.
(10) When the intake air amount GA is less than the determination intake air amount GATh, the intake air amount GA becomes too small, and there is a risk that a misfire may occur in the internal combustion engine 10 . Therefore, when the intake air amount GA becomes less than the determination intake air amount GATh when the throttle opening degree SL is decreased by executing the rapid decrease process, it is determined that the intake air amount GA is less than the determination intake air amount GATh. On the condition that the air-fuel ratio has continued for the duration time TMTh or longer, the rapid decrease process is terminated and the air-fuel ratio enrichment process is started. As a result, the air-fuel ratio AF can be made richer than the stoichiometric air-fuel ratio AFSt. As a result, misfires are less likely to occur in the internal combustion engine 10 than when the stoichiometric air-fuel ratio AFSt is set as the target air-fuel ratio AFTr. As a result, it is possible to suppress an increase in the amount of unburned fuel reaching the three-way catalyst 17 due to a misfire. Therefore, it is possible to prevent the temperature of the three-way catalyst 17 from becoming too high.

(11) In the air-fuel ratio enrichment process, the higher the possibility of a misfire occurring in the internal combustion engine 10, the richer the air-fuel ratio is set than the target air-fuel ratio AFTr. Therefore, it is possible to enhance the effect of suppressing the occurrence of misfire caused by the execution of the air-fuel ratio enrichment process.

(12) It should be noted that the higher the possibility of a misfire occurring in the internal combustion engine 10, the shorter the determination continuation time TMTh is set. By varying the determination continuation time TMTh in this way, the air-fuel ratio enrichment process can be started earlier as the possibility of misfire occurrence increases.

(Change example)
Each of the above embodiments can be implemented with the following modifications. Each of the above-described embodiments and the following modifications can be implemented in combination with each other within a technically consistent range.

In the second embodiment, in the air-fuel ratio enrichment process, if the target air-fuel ratio AFTr is varied according to the amount of EGR gas recirculated to the intake passage 12 by the EGR device 20, It is not necessary to vary the target air-fuel ratio AFTr. Similarly, in the air-fuel ratio enrichment process, if the target air-fuel ratio AFTr is varied according to the amount of EGR gas recirculated to the intake passage by the EGR device 20, the target air-fuel ratio AFTr is varied according to the engine speed NE. It does not have to be changed.

In the second embodiment, in the air-fuel ratio enrichment process, if the target air-fuel ratio AFTr is varied according to the intake air amount GA, It is not necessary to vary the target air-fuel ratio AFTr. Similarly, in the air-fuel ratio enrichment process, if the target air-fuel ratio AFTr is varied according to the intake air amount GA, it is not necessary to vary the target air-fuel ratio AFTr according to the engine speed NE.

In the second embodiment, in the air-fuel ratio enrichment process, if the target air-fuel ratio AFTr is varied according to the engine speed NE, It is not necessary to vary the target air-fuel ratio AFTr. Similarly, in the air-fuel ratio enrichment process, if the target air-fuel ratio AFTr is varied according to the engine speed NE, it is not necessary to vary the target air-fuel ratio AFTr according to the intake air amount GA.

In the second embodiment, in the air-fuel ratio enrichment process, the target air-fuel ratio AFTr is variable during the air-fuel ratio enrichment process if an air-fuel ratio on the richer side than the stoichiometric air-fuel ratio AFSt can be set as the target air-fuel ratio AFTr. You don't have to.

- In the second embodiment, when the air-fuel ratio enrichment process is started, the rapid decrease process is terminated. However, the rapid decrease process may be continued even after the air-fuel ratio enrichment process is started. Even in this case, the occurrence of misfires in the internal combustion engine 10 can be suppressed. Note that if the execution of the rapid decrease process continues even after the air-fuel ratio enrichment process is started in this way, the power generation process and the ignition timing retardation process that have been executed before the start of the air-fuel ratio enrichment process Execution of processing may also be continued.

・In the second embodiment, if fuel injection is to be stopped immediately upon detection of a misfire during execution of the rapid decrease process, the air-fuel ratio enrichment process will be executed even if the intake air amount GA becomes equal to or less than the determination intake air amount GATh. You don't have to.

- In the first embodiment, during execution of the rapid decrease process, the fuel cut process may be started after a misfire is detected.
- The determination continuation time TMTh does not have to be varied according to the diagnosis result of the blockage diagnosis unit 137 .

If the determination continuation time TMTh is varied according to the amount of EGR gas recirculated to the intake passage 12 by the EGR device 20, it is not necessary to vary the determination continuation time TMTh according to the intake air amount GA. Similarly, if the determination continuation time TMTh is varied according to the amount of EGR gas recirculated to the intake passage 12 by the EGR device 20, it is not necessary to vary the determination continuation time TMTh according to the engine speed NE. .

If the determination continuation time TMTh is varied according to the intake air amount GA, it is not necessary to vary the determination continuation time TMTh according to the amount of EGR gas recirculated to the intake passage 12 by the EGR device 20 . Similarly, if the determination continuation time TMTh is varied according to the intake air amount GA, it is not necessary to vary the determination continuation time TMTh according to the engine speed NE.

If the determination continuation time TMTh is varied according to the engine speed NE, it is not necessary to vary the determination continuation time TMTh according to the amount of EGR gas recirculated to the intake passage 12 by the EGR device 20 . Similarly, if the determination continuation time TMTh is varied according to the engine speed NE, it is not necessary to vary the determination continuation time TMTh according to the intake air amount GA.

- The determination continuation time TMTh may be fixed at a certain value.
In the second embodiment, when the intake air amount GA becomes equal to or less than the determination intake air amount GATh during execution of the rapid decrease process, the air-fuel ratio You may make it start the enrichment process.

In the first embodiment, when the intake air amount GA becomes equal to or less than the determination intake air amount GATh during execution of the sudden decrease process, the fuel is cut as soon as it is detected that the intake air amount GA is equal to or less than the determination intake air amount GATh. You may make it start processing.

- The lower limit guard PELm is varied according to changes in the EGR rate Y during execution of the sudden drop process. However, the lower limit guard PELm may be held until the reduction of the EGR opening REGR is completed during the rapid decrease process. Then, after the reduction of the EGR opening REGR is completed, the holding of the lower limit guard PELm may be released and the throttle opening SL may be reduced.

Further, during execution of the sudden drop process, the lower limit guard PELm is held from the start of the sudden drop process until a predetermined time elapses, and the lower limit guard PELm is gradually decreased after the elapse of the specified time. good too.

- During execution of the rapid decrease process, the battery 77 need not be charged by the power generation process when the lower limit guard PELm is greater than the required engine output PEQ. In this case, when the lower limit guard PELm is greater than the required engine output PEQ, the ignition timing retarding process may be executed regardless of the state of charge SOC.

In the rapid decrease process, if the rate of decrease of the EGR opening REGR can be made higher than the rate of decrease of the throttle opening SL, the lower limit guard PELm need not be used. For example, in the sudden drop process, the EGR valve 22 is closed. At this time, the throttle opening SL may be maintained until the EGR valve 22 is closed. That is, the reduction of the throttle opening SL may be started after the EGR valve 22 is closed.

When the EGR valve 22 is closed in this way and then the throttle opening degree SL is started to decrease, there is a period during which the actual engine output PE is higher than the required engine output PEQ. During this period, the power generation process may be executed. In this case, it is preferable to drive the first motor generator 71 so that the greater the difference between the actual engine output PE and the requested engine output PEQ, the greater the amount of power generation.

- The determination storage amount SOCTh may be varied. For example, when it can be predicted that the amount of electric power generated by first motor generator 71 will increase during execution of the rapid decrease process, the determination storage amount SOCTh may be made smaller than when this is not the case.

If a misfire is detected in the internal combustion engine 10 when the required engine output PEQ is greatly reduced, the fuel injection is stopped immediately, and the rapid decrease process does not have to be executed.
- Execution of the push-down process may not be prohibited when the vehicle speed VS is equal to or higher than the determination vehicle speed VSTh.

- It is not necessary to prohibit execution of the push-up process when the vehicle speed VS is equal to or higher than the determination vehicle speed VSTh.
- When it is not determined that the air-fuel mixture is stably burning in the cylinder 11, it is not necessary to perform not only the push-down process but also the push-up process. By adopting such a control configuration, it is possible to suppress the occurrence of misfires in the internal combustion engine 10 as compared with the case where the push-down process is executed even when the combustion of the air-fuel mixture is unstable.

If the hybrid vehicle to which the control device 100 is applied has an internal combustion engine and a motor generator as power sources of the vehicle, and the output torque of the internal combustion engine can be input to the motor generator via the power split mechanism, The vehicle may have a configuration different from that of the hybrid vehicle shown in FIG.

Next, technical ideas that can be grasped from the above embodiments and modified examples will be described.
(a) An internal combustion engine and a motor generator are provided as power sources of the vehicle, and the internal combustion engine includes an EGR device that recirculates the exhaust gas discharged from the cylinder into the exhaust passage to the intake passage as EGR gas, and an EGR device provided in the exhaust passage. and a hybrid vehicle in which the EGR device is provided with an EGR valve that adjusts the amount of EGR gas recirculated to the intake passage,
When the amount of decrease in the required engine output, which is the required output of the internal combustion engine, is less than the determination amount of decrease, the opening of the throttle valve provided in the intake passage and the EGR are controlled in accordance with the change in the required engine output. a normal processing unit that adjusts the opening of the valve;
When the amount of decrease in the required engine output is greater than or equal to the determination amount of decrease, the throttle valve opening and A control device for a hybrid vehicle, comprising: a rapid decrease processing unit that executes a rapid decrease processing for decreasing the degree of opening of the EGR valve.

An internal combustion engine applied to a hybrid vehicle is sometimes provided with an EGR device that recirculates exhaust gas flowing through an exhaust passage to an intake passage as EGR gas. The EGR device has an EGR valve that adjusts the amount of exhaust gas recirculated to the intake passage. If the ratio of the intake air to the gas introduced into the cylinder of the internal combustion engine is too small, the internal combustion engine may misfire. Therefore, when the opening of the throttle valve is reduced because the required engine output, which is the required output of the internal combustion engine, is reduced, the opening of the EGR valve is reduced in accordance with the reduction in the opening of the throttle valve. However, if the responsiveness of the EGR valve is worse than the responsiveness of the throttle valve, even if the opening of the EGR valve is decreased in accordance with the decrease in the opening of the throttle valve, there will be no suction due to the decrease in the opening of the throttle valve. The decrease in the amount of EGR gas recirculated to the intake passage may be delayed with respect to the decrease in air amount. If such a delay occurs, the ratio of the intake air to the gas introduced into the cylinder becomes too small, and misfire may occur in the internal combustion engine.

When the amount of decrease in the requested engine output is equal to or greater than the determination amount of decrease, the amount of intake air is greatly decreased, so the ratio of the intake air to the gas introduced into the cylinder tends to decrease. Therefore, according to the above configuration, when the amount of decrease in the required engine output is equal to or greater than the determination amount of decrease, the speed of decrease in the degree of opening of the EGR valve is higher than the speed of decrease in the degree of opening of the throttle valve. The degree of opening and the degree of opening of the EGR valve are reduced. By decreasing the opening of the EGR valve with priority over the opening of the throttle valve in this way, the amount of EGR gas recirculated to the intake passage relative to the decrease in intake air caused by the decrease in the opening of the throttle valve is suppressed. As a result, it is possible to prevent the intake air from becoming too small in the gas introduced into the cylinder. Therefore, it is possible to suppress the occurrence of misfire in the internal combustion engine when the required engine output is reduced.

Reference Signs List 10 Internal combustion engine 11 Cylinder 12 Intake passage 12A Branch passage portion 13 Throttle valve 15 Fuel injection valve 16 Exhaust passage 17 Three-way catalyst 20 EGR device 211 EGR Port 22 EGR valve 40 Power distribution integration mechanism 71 First motor generator 72 Second motor generator 77 Battery 100 Control device 110 Motor control unit 130 Engine control unit 131 Combustion determination unit 132 Processing unit 133 Sudden decrease processing unit 134 Guard setting unit 135 Ignition timing adjustment unit 136 Injection valve control unit 137 Blockage diagnosis unit.

Claims (12)

An internal combustion engine, a motor generator, and a power split device having a plurality of gears meshing with each other are provided, and the output torque of the internal combustion engine is input to the motor generator via the power split device to the motor generator. The internal combustion engine includes an EGR device that recirculates exhaust gas discharged from a cylinder into an exhaust passage to an intake passage as EGR gas, and a catalyst provided in the exhaust passage. Applied to a hybrid vehicle in which an EGR valve for adjusting the amount of EGR gas to be supplied is provided in the EGR device ,
a combustion determination unit that determines whether or not an air-fuel mixture is stably combusted in the cylinder of the internal combustion engine when the engine is running;
a motor control unit that controls the motor generator;
When the amount of decrease in the required engine output, which is the required output of the internal combustion engine, is less than the determination amount of decrease, the degree of opening of the throttle valve provided in the intake passage and the degree of opening of the EGR valve are adjusted according to the change in the required engine output. a normal processing unit that adjusts the degree of opening;
When the amount of decrease in the required engine output is greater than or equal to the determination amount of decrease, the throttle valve opening and a sudden drop processing unit that executes a sudden drop process that reduces the opening of the EGR valve ,
When it is determined that the air-fuel mixture is stably combusted in the cylinder, the motor control unit performs push-down processing for outputting torque from the motor generator in a direction in which the load applied to the internal combustion engine increases. and does not execute the push-down process when it is not determined that the air-fuel mixture is stably combusted in the cylinder. When the torque output from the motor generator by the execution of the pressing process is the first motor torque,
When it is not determined that the air-fuel mixture is stably combusted in the cylinder, the motor control unit applies the second motor torque, which is the torque in the opposite direction to the direction of the first motor torque. The control device for a hybrid vehicle according to claim 1, wherein a push-up process for outputting from the motor generator is executed. 3. When the vehicle speed is equal to or higher than the determination vehicle speed, the motor control unit does not execute the push-down process even if it is determined that the air-fuel mixture is stably combusted in the cylinder. The hybrid vehicle control device according to . The hybrid vehicle according to any one of claims 1 to 3 , wherein, in the rapid decrease processing, the sudden decrease processing unit closes the EGR valve and then decreases the opening degree of the throttle valve. Control device. The rapid decrease processing unit adjusts the opening of the throttle valve so that the opening corresponds to the larger one of the required engine output and the lower limit guard in the rapid decrease processing. cage,
The motor control unit controls the motor generator so that, when the lower limit guard is greater than the required engine output, the amount of power generated by the motor generator is an amount corresponding to the difference between the lower limit guard and the required engine output. The hybrid vehicle control device according to any one of claims 1 to 3, wherein a power generation process for driving is executed. The control device for a hybrid vehicle according to claim 5 , further comprising a guard setting unit that sets the lower limit guard so that the lower limit guard increases as the EGR rate during execution of the rapid decrease process increases. An ignition timing adjustment unit that adjusts the ignition timing of the internal combustion engine,
The motor control unit executes the power generation process when the sudden decrease process is executed under a situation where the storage amount of a battery in which electric power generated by the motor generator is stored is less than the determination storage amount, The power generation process is not executed when the rapid decrease process is executed in a situation where the stored power amount is equal to or greater than the determined stored power amount,
The ignition timing adjustment unit retards the ignition timing when the sudden decrease process is executed under the condition that the stored electricity amount is equal to or greater than the determined stored electricity amount, thereby causing the difference between the engine output and the required engine output. 7. The control device for a hybrid vehicle according to claim 5 or 6 , wherein ignition timing retardation processing for suppressing the ignition timing is executed. An injection valve control unit that controls a fuel injection valve of the internal combustion engine,
The injection valve control unit causes the fuel injection valve to perform fuel injection on the condition that the intake air amount is equal to or less than a judgment intake air amount when the opening degree of the throttle valve is decreased by executing the rapid decrease process. The hybrid vehicle control device according to any one of claims 1 to 7 , further comprising: starting a fuel cut process for stopping. When the opening degree of the throttle valve is decreased by executing the rapid decrease process, the injection valve control unit determines that the duration of a state in which the amount of intake air is less than the determination intake air amount is equal to or greater than the determination duration. The fuel cut process is started on the condition that
The determination duration time is shorter as the amount of EGR gas recirculated to the intake passage by the EGR device is larger, shorter as the amount of intake air is smaller, and shorter as the engine speed is higher. Control device. The internal combustion engine has a plurality of cylinders, and the downstream portion of the intake passage is configured to branch for each cylinder,
When a passage portion of the intake passage that is branched for each cylinder is a branch passage portion, the EGR device has a plurality of EGR ports connected to the plurality of branch passage portions,
The control device includes a blockage diagnosis unit that diagnoses whether or not there is a blockage of the EGR port among the EGR ports,
10. The determination duration time is shorter when it is diagnosed that there is a blocked EGR port than when it is not diagnosed that there is a blocked EGR port. A control device for a hybrid vehicle as described. An injection valve control unit that controls a fuel injection valve of the internal combustion engine,
The injection valve control unit determines that the air-fuel ratio is a value on the rich side on the condition that the intake air amount is equal to or less than the judgment intake air amount when the opening degree of the throttle valve is decreased by executing the rapid decrease process. 8. The hybrid vehicle control device according to any one of claims 1 to 7 , wherein an air-fuel ratio rich process is executed to control the fuel injection valve such that In the air-fuel ratio rich process, the injection valve control unit shifts the air-fuel ratio to the rich side as the amount of EGR gas recirculated to the intake passage by the EGR device increases, and shifts the air-fuel ratio to the rich side as the amount of intake air decreases. , and the fuel injection valve is controlled such that the higher the engine speed, the richer the air - fuel ratio becomes.

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