JP7447773B2 - engine equipment - Google Patents

Description

The present invention relates to an engine device.

Conventionally, this type of engine device includes an engine and a purification catalyst that purifies engine exhaust gas, and when a warm-up request for the purification catalyst is made, a constant target output is achieved. A system has been proposed that performs catalyst warm-up control to control the engine (for example, see Patent Document 1).

Japanese Patent Application Publication No. 2007-32317

In such engine devices, when executing exhaust restriction control that limits the displacement of the engine, lean control is performed to control the engine so that the equivalence ratio is smaller than a value of 1, and lean control is performed to control the engine so that the equivalence ratio becomes larger than a value of 1. It has been considered to execute rich control for controlling the engine in this order. At this time, if lean control and rich control are both executed based on the cumulative air amount from the start of exhaust restriction control (lean control), rich control may not be performed properly due to variations in the cumulative air amount at the start of rich control. There may be cases where it cannot be executed.

The main purpose of the engine device of the present invention is to execute rich control more appropriately.

The engine device of the present invention employs the following means to achieve the above-mentioned main purpose.

The engine device of the present invention includes:
engine and
a purification catalyst that purifies the exhaust gas of the engine;
In the execution of exhaust restriction control that limits the displacement of the engine, lean control that controls the engine so that the equivalence ratio is smaller than a value 1, and lean control that controls the engine so that the equivalence ratio becomes larger than the value 1. a control device that executes the rich control to be controlled in this order;
An engine device comprising:
The control device includes:
In the lean control, at least one of a target output, a target equivalence ratio, and a target ignition timing is set based on a first integrated air amount that is an integrated value of the intake air amount from the start of the lean control, and the control the engine,
In the rich control, at least one of the target output, the target equivalence ratio, and the target ignition timing is set based on a second integrated air amount that is an integrated value of the intake air amount since the start of the rich control. to control the engine;
The gist is that.

In the engine device of the present invention, lean control is performed to control the engine so that the equivalence ratio becomes smaller than the value 1, and lean control is performed to control the engine so that the equivalence ratio becomes larger than the value 1, in executing the exhaust restriction control that limits the displacement of the engine. Execute rich control to control the engine in this order. In the lean control, at least one of the target output, the target equivalence ratio, and the target ignition timing is set based on the first integrated air amount, which is the integrated value of the intake air amount since the start of the lean control, and the engine and in the rich control, at least one of the target output, the target equivalence ratio, and the target ignition timing is set based on a second integrated air amount that is an integrated value of the intake air amount from the start of the rich control. control the engine. As a result, the target output, the target equivalence, and The engine can be controlled by setting at least one of the ratio and the target ignition timing more appropriately. As a result, rich control can be executed more appropriately.

In the engine device of the present invention, the control device may perform the target output in the lean control based on the first integrated air amount and a starting temperature that is a temperature of the engine at the time of starting the exhaust restriction control. , the engine is controlled by setting at least one of the target equivalence ratio and the target ignition timing, and in the rich control, the target is set based on the second integrated air amount and the starting temperature. The engine may be controlled by setting at least one of the output, the target equivalence ratio, and the target ignition timing.

In the engine device of the present invention, the control device is configured to shift to the rich control when a transition condition including a condition in which the amount of oxygen stored in the purification catalyst reaches a threshold value or more is established during execution of the lean control. Good too. In this case, the present invention is significant because the first integrated air amount varies when the oxygen storage amount of the purification catalyst reaches the threshold value or more and the transition condition is satisfied.

1 is a configuration diagram schematically showing the configuration of a hybrid vehicle 20 equipped with an engine device 21 as an embodiment of the present invention. FIG. 2 is an explanatory diagram showing an outline of the configuration of an engine device 21. FIG. 2 is a flowchart showing an example of a catalyst warm-up control routine executed by the engine ECU 24. FIG. The rotational speed Ne of the engine 22, the temperature Tc of the purification catalyst 135a, whether or not catalyst warm-up control is executed, the first integrated air amount Qas1, the second integrated air amount Qas2, the target power Pe*, the target equivalence ratio φ*, the target ignition FIG. 3 is an explanatory diagram showing an example of the state of time IT*.

Next, a mode for carrying out the present invention will be described using examples.

FIG. 1 is a block diagram schematically showing the structure of a hybrid vehicle 20 equipped with an engine device 21 as an embodiment of the present invention, and FIG. 2 is an explanatory diagram schematically showing the structure of the engine device 21. As shown in FIG. As shown in FIG. 1, the hybrid vehicle 20 of the embodiment includes an engine device 21, a planetary gear 30, motors MG1 and MG2, inverters 41 and 42, a battery 50, and a hybrid electronic control unit (hereinafter referred to as HVECU). )70. Here, the engine device 21 includes an engine 22 and an engine electronic control unit (hereinafter referred to as "engine ECU") 24.

The engine 22 is configured as a four-cylinder internal combustion engine that uses fuel such as gasoline or diesel oil to output power through four strokes: intake, compression, expansion (explosive combustion), and exhaust. As shown in FIG. 2, the engine 22 includes a port injection valve 126 that injects fuel into an intake port, and an in-cylinder injection valve 127 that injects fuel into a cylinder. The engine 22 has a port injection valve 126 and an in-cylinder injection valve 127, so that it can be operated in any one of a port injection mode, an in-cylinder injection mode, and a shared injection mode. In the port injection mode, air purified by the air cleaner 122 is sucked into the intake pipe 123 and passed through the throttle valve 124 and surge tank 125, and fuel is injected from the port injection valve 126 downstream of the surge tank 125 in the intake pipe 123. to mix air and fuel. This air-fuel mixture is then sucked into the combustion chamber 129 through the intake valve 128 and exploded and combusted by the electric spark from the spark plug 130, converting the reciprocating motion of the piston 132 pushed down by the energy into the rotational motion of the crankshaft 23. do. In the direct injection mode, air is sucked into the combustion chamber 129 as in the port injection mode, fuel is injected from the direct injection valve 127 during the intake stroke and/or during the compression stroke, and an electric spark is generated by the spark plug 130. The rotational motion of the crankshaft 23 is obtained by causing explosive combustion. In the shared injection mode, fuel is injected from the port injection valve 126 when air is taken into the combustion chamber 129, and fuel is injected from the in-cylinder injection valve 127 during the intake stroke or compression stroke, and an electric spark from the spark plug 130 causes an explosion. The rotational motion of the crankshaft 23 is obtained by combustion. These injection modes are switched based on the operating state of the engine 22. Exhaust gas discharged from the combustion chamber 129 to the exhaust pipe 134 via the exhaust valve 133 is discharged to the outside air via the purification device 135. The purification device 135 includes a purification catalyst (three-way catalyst) 135a that purifies harmful components such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx) in exhaust gas. The purification catalyst 135a is configured to be able to store and desorb oxygen.

The engine 22 is operationally controlled by an engine electronic control unit (hereinafter referred to as "engine ECU") 24. Although not shown, the engine ECU 24 is configured as a microprocessor centered on a CPU, and in addition to the CPU, includes a ROM that stores processing programs, a RAM that temporarily stores data, and a flash memory that stores and holds data. , input/output ports, and communication ports.

Signals from various sensors necessary to control the operation of the engine 22 are input to the engine ECU 24 via an input port. Signals input to the engine ECU 24 include, for example, the crank angle θcr from the crank position sensor 140 that detects the rotational position of the crankshaft 23 of the engine 22, and the water temperature sensor 142 that detects the temperature of the cooling water of the engine 22. One example is the cooling water temperature Tw. Cam angles θci and θco from a cam position sensor 144 that detects the rotational position of the intake camshaft that opens and closes the intake valve 128 and the rotational position of the exhaust camshaft that opens and closes the exhaust valve 133 can also be cited. The throttle opening TH from the throttle valve position sensor 124a that detects the position of the throttle valve 124, the intake air amount Qa from the air flow meter 123a installed upstream of the throttle valve 124 of the intake pipe 123, and the intake air amount Qa of the intake pipe 123. The intake air temperature Ta from the temperature sensor 123t attached upstream of the throttle valve 124 and the surge pressure Ps from the pressure sensor 125a attached to the surge tank 125 can also be cited. The front air-fuel ratio AF1 from the front air-fuel ratio sensor 137 installed in the exhaust pipe 134 on the upstream side of the purification device 135, and the rear air-fuel ratio sensor 138 installed in the exhaust pipe 134 on the downstream side of the purification device 135. The rear air-fuel ratio AF2 can also be mentioned.

The engine ECU 24 outputs various control signals for controlling the operation of the engine 22 via an output port. Examples of the signals output from the engine ECU 24 include a control signal to the throttle valve 124, a control signal to the port injection valve 126, a control signal to the in-cylinder injection valve 127, and a control signal to the spark plug 130. Can be done.

Engine ECU 24 is connected to HVECU 70 via a communication port. The engine ECU 24 calculates the rotation speed Ne of the engine 22 based on the crank angle θcr of the engine 22 from the crank position sensor 140. In addition, the engine ECU 24 calculates the load factor (the volume of air actually taken in in one cycle relative to the stroke volume per cycle of the engine 22) based on the intake air amount Qa from the air flow meter 123a and the rotational speed Ne of the engine 22. (ratio of ) KL is calculated. Further, the engine ECU 24 estimates the temperature Tc of the purification catalyst 135a of the purification device 135 based on the cooling water temperature Tw from the water temperature sensor 142, the rotational speed Ne of the engine 22, and the load factor KL. In addition, the engine ECU 24 determines the oxygen occlusion of the purification catalyst 135a of the purification device 135 based on the front air-fuel ratio AF1 from the front air-fuel ratio sensor 137 and/or the rear air-fuel ratio AF2 from the rear air-fuel ratio sensor 138 and the intake air amount Qa. Estimate the amount OS.

As shown in FIG. 1, the planetary gear 30 is configured as a single pinion type planetary gear mechanism. The sun gear of the planetary gear 30 is connected to the rotor of the motor MG1. A drive shaft 36 connected to drive wheels 39a and 39b via a differential gear 38 is connected to the ring gear of the planetary gear 30. A crankshaft 23 of an engine 22 is connected to the carrier of the planetary gear 30 via a damper 28.

The motor MG1 is configured, for example, as a synchronous generator motor, and has a rotor connected to the sun gear of the planetary gear 30, as described above. The motor MG2 is configured as, for example, a synchronous generator motor, and has a rotor connected to the drive shaft 36. Inverters 41 and 42 are used to drive motors MG1 and MG2, and are connected to battery 50 via power line 54. The motors MG1 and MG2 are rotationally driven by a motor electronic control unit (hereinafter referred to as "motor ECU") 40 that controls switching of a plurality of switching elements (not shown) of inverters 41 and 42.

Although not shown, the motor ECU 40 is configured as a microprocessor centered on a CPU, and in addition to the CPU, includes a ROM for storing processing programs, a RAM for temporarily storing data, and a flash memory for storing and retaining data. , input/output ports, and communication ports. Signals from various sensors necessary to drive and control the motors MG1 and MG2 are input to the motor ECU 40 via input ports. Examples of signals input to the motor ECU 40 include rotational positions θm1 and θm2 of the rotors of the motors MG1 and MG2 from a rotational position sensor (not shown) that detects the rotational positions of the rotors of the motors MG1 and MG2; Examples include phase currents Iu1, Iv1, Iu2, and Iv2 of each phase of motors MG1 and MG2 from a current sensor (not shown) that detects phase currents flowing through each phase of MG2. The motor ECU 40 outputs switching control signals to a plurality of switching elements (not shown) of the inverters 41 and 42 via an output port. Motor ECU 40 is connected to HVECU 70 via a communication port. Motor ECU 40 calculates electrical angles θe1, θe2 and rotational speeds Nm1, Nm2 of motors MG1, MG2 based on rotational positions θm1, θm2 of the rotors of motors MG1, MG2 from rotational position sensors.

The battery 50 is configured as, for example, a lithium ion secondary battery or a nickel metal hydride secondary battery, and is connected to the inverters 41 and 42 via the power line 54, as described above. This battery 50 is managed by a battery electronic control unit (hereinafter referred to as "battery ECU") 52.

Although not shown, the battery ECU 52 is configured as a microprocessor centered on a CPU, and in addition to the CPU, includes a ROM for storing processing programs, a RAM for temporarily storing data, and a flash memory for storing and retaining data. , input/output ports, and communication ports. Signals from various sensors necessary for managing the battery 50 are input to the battery ECU 52 via an input port. Examples of signals input to the battery ECU 52 include voltage Vb of the battery 50 from a voltage sensor (not shown) attached between terminals of the battery 50, and voltage Vb of the battery 50 from a current sensor (not shown) attached to an output terminal of the battery 50. 50, and the temperature Tb of the battery 50 from a temperature sensor (not shown) attached to the battery 50. Battery ECU 52 is connected to HVECU 70 via a communication port. The battery ECU 52 calculates the storage percentage SOC of the battery 50 based on the integrated value of the current Ib of the battery 50 from the current sensor. The power storage ratio SOC is the ratio of the capacity of electric power that can be discharged from the battery 50 to the total capacity of the battery 50.

Although not shown, the HVECU 70 is configured as a microprocessor centered on a CPU, and in addition to the CPU, includes a ROM that stores processing programs, a RAM that temporarily stores data, a flash memory that stores and holds data, Equipped with input/output ports and communication ports. Signals from various sensors are input to the HVECU 70 via input ports. Examples of signals input to the HVECU 70 include an ignition signal from an ignition switch 80 and a shift position SP from a shift position sensor 82 that detects the operating position of the shift lever 81. Further, the accelerator opening degree Acc from the accelerator pedal position sensor 84 which detects the amount of depression of the accelerator pedal 83, the brake pedal position BP from the brake pedal position sensor 86 which detects the amount of depression of the brake pedal 85, and the brake pedal position BP from the vehicle speed sensor 88. The vehicle speed V and the outside air temperature Tout from the outside air temperature sensor 89 can also be cited. As described above, the HVECU 70 is connected to the engine ECU 24, motor ECU 40, and battery ECU 52 via the communication port.

In the hybrid vehicle 20 of the embodiment configured in this way, the HVECU 70, the engine ECU 24, and the motor ECU 40 cooperatively control the hybrid drive mode (HV drive mode) in which the vehicle runs with the rotation of the engine 22, and the mode in which the rotation of the engine 22 is stopped. The vehicle travels in electric driving mode (EV driving mode).

Further, in the hybrid vehicle 20, when the engine 22 is operated, intake air amount control, fuel injection control, ignition control, etc. are performed based on the target power Pe* of the engine 22. Intake air amount control is performed by controlling the opening degree of throttle valve 124. Fuel injection control is performed by controlling the amount of fuel injected from the port injection valve 126 and the cylinder injection valve 127 in port injection mode, in-cylinder injection mode, and shared injection mode. Ignition control is performed by controlling the ignition timing of the spark plug 130.

Further, in the hybrid vehicle 20, when the fuel cut condition is satisfied in the HV driving mode, the fuel cut of the engine 22 is executed and the engine 22 is motored by the motor MG1. As the fuel cut condition, for example, a condition is used in which the accelerator is turned off when the storage rate SOC of the battery 50 is relatively large in the HV driving mode.

In addition, in the hybrid vehicle 20, if execution of the exhaust restriction control is required, such as when the engine 22 has finished starting, the exhaust restriction control is executed. Here, the exhaust restriction control is a control that limits the displacement of the engine 22 in order to suppress deterioration of emissions. In the embodiment, in the exhaust restriction control, fuel injection control is performed in the in-cylinder injection mode in consideration of the combustion stability of the engine 22 and the like. In addition, in the embodiment, the case where execution of exhaust restriction control is requested is when temperature Tc of purification catalyst 135a is less than threshold value Tcref (purification catalyst 135a is inactive), and execution of catalyst warm-up control is requested. In addition to considering the case where the exhaust gas restriction control is performed, the catalyst warm-up control is executed as the exhaust restriction control. Catalyst warm-up control is control for controlling the engine 22 by making the ignition timing of the engine 22 later than the optimum ignition timing (MBT: Minimum advance for Best Torque) in order to promote the warm-up of the purification catalyst 135a.

Next, the operation of the hybrid vehicle 20 according to the embodiment configured in this manner will be described, in particular, the details of the catalyst warm-up control. FIG. 3 is a flowchart showing an example of a catalyst warm-up control routine executed by the engine ECU 24. This routine is executed when execution of catalyst warm-up control is requested, such as when starting of the engine 22 is completed.

When the catalyst warm-up control routine of FIG. 3 is executed, the engine ECU 24 first executes catalyst lean control in the catalyst warm-up control (steps S100 to S104). Here, the catalyst lean control is control for controlling the engine 22 so that the ignition timing of the engine 22 becomes later than the optimum ignition timing and the equivalence ratio becomes smaller than the value 1 (the air-fuel ratio becomes lean). . The equivalence ratio is the stoichiometric air-fuel ratio/air-fuel ratio, and the target equivalence ratio is the target value of the equivalence ratio.

In the catalyst lean control, first, the starting water temperature Twst and the first integrated air amount Qas1 are input (step S100). Next, target power Pe*, target equivalence ratio φ*, and target ignition timing IT* are set based on the input starting water temperature Twst and first integrated air amount Qas1 (step S102). Then, the engine 22 is controlled using the set target power Pe*, target equivalence ratio φ*, and target ignition timing IT* (step S104).

Here, the cooling water temperature Tw detected by the water temperature sensor 142 at the time of starting the catalyst warm-up control (for example, when starting of the engine 22 is completed) is input as the starting water temperature Twst. A value calculated as an integrated value of the intake air amount Qa detected by the air flow meter 123a from the start of the catalyst warm-up control is input as the first integrated air amount Qas1.

The target power Pe*, the target equivalence ratio φ*, and the target ignition timing IT* in catalyst lean control are, for example, based on the starting water temperature Twst and the first integrated air amount Qas1, the target power Pe*, the target equivalence ratio φ*, and the target It is estimated by applying the starting water temperature Twst and the first integrated air amount Qas1 to a first map predetermined as a relationship between the ignition timing IT* and the ignition timing IT*. The target power Pe* is set to increase as the starting water temperature Twst increases and as the first integrated air amount Qas1 increases. The target equivalence ratio φ* is set such that the higher the starting water temperature Twst is, the smaller it becomes with respect to the value 1, and the larger the first integrated air amount Qas1 is, the smaller the target equivalence ratio φ* is with respect to the value 1. The target ignition timing IT* is set within a range later than the optimum ignition timing, so that the higher the starting water temperature Twst is, the later the target ignition timing IT* is, and the higher the first integrated air amount Qas1 is, the later the target ignition timing IT* is. These trends are based on considerations such as the combustion stability of the engine 22 and the purification performance of the purification catalyst 135a.

Subsequently, the oxygen storage amount OS of the purification catalyst 135a is input (step S110), and the input oxygen storage amount OS of the purification catalyst 135a is compared with the threshold value OSref (step S112). Here, the oxygen storage amount OS of the purification catalyst 135a is determined by the front air-fuel ratio AF1 detected by the front air-fuel ratio sensor 137 and/or the rear air-fuel ratio AF2 detected by the rear air-fuel ratio sensor 138, and the air flow meter 123a. A value estimated based on the intake air amount Qa is input. The threshold OSref is a threshold used to determine whether a transition condition for transitioning from catalyst lean control to catalyst rich control, which will be described later, is satisfied in catalyst warm-up control.

When the oxygen storage amount OS of the purification catalyst 135a is less than the threshold OSref in step S112, it is determined that the transition condition is not satisfied, and the process returns to step S100. In this way, the catalyst lean control in the catalyst warm-up control is continued. In this way, the processes of steps S100 to S112 are repeatedly executed, and when the oxygen storage amount OS of the purification catalyst 135a reaches the threshold value OSref or more in step S112, it is determined that the transition condition is satisfied, and the rich control for the catalyst in the catalyst warm-up control is performed. (Steps S120 to S124). Here, the catalyst rich control is control for controlling the engine 22 so that the ignition timing of the engine 22 becomes later than the optimum ignition timing and the equivalence ratio becomes larger than the value 1 (the air-fuel ratio becomes rich). .

In the catalyst rich control, first, the starting water temperature Twst and the second integrated air amount Qas2 are input (step S120). Next, target power Pe*, target equivalence ratio φ*, and target ignition timing IT* are set based on the input starting water temperature Twst and second integrated air amount Qas2 (step S122). Then, the engine 22 is controlled using the set target power Pe*, target equivalence ratio φ*, and target ignition timing IT* (step S124).

Here, the method of inputting the starting water temperature Twst has been described above. As the second integrated air amount Qas2, a value calculated as an integrated value of the intake air amount Qa detected by the air flow meter 123a from the start of the catalyst rich control is input.

The target power Pe*, target equivalence ratio φ*, and target ignition timing IT* in catalyst rich control are, for example, based on the starting water temperature Twst and the second integrated air amount Qas2, the target power Pe*, the target equivalence ratio φ*, and the target It is estimated by applying the starting water temperature Twst and the second integrated air amount Qas2 to a second map predetermined as a relationship between the ignition timing IT* and the ignition timing IT*. The target power Pe* is set to increase as the starting water temperature Twst increases and as the second integrated air amount Qas2 increases. The target equivalence ratio φ* is set such that the higher the starting water temperature Twst, the larger the value 1, and the larger the second integrated air amount Qas2, the larger the value 1. The target ignition timing IT* is set within a range later than the optimum ignition timing so that the higher the starting water temperature Twst is, the later the target ignition timing IT* is, and the later the second integrated air amount Qas2 is, the later the target ignition timing IT* is. These trends are based on the same reasons as the trends in the first map.

Subsequently, the number Nc of injection cylinders is input (step S130), and the input number Nc of injection cylinders is compared with a threshold value Ncref (step S132). Here, the number of injection cylinders Nc is the number of cylinders in which fuel is injected from the in-cylinder injection valve 127 under catalyst rich control. The threshold value Ncref is a threshold value used to determine whether a termination condition for terminating the catalyst warm-up control (catalyst rich control in the catalyst warm-up control) is satisfied. Note that in the embodiment, the target power Pe* and the target power Pe* in the catalyst lean control and the catalyst rich control of the catalyst warm-up control are set so that the catalyst warm-up control is terminated when the temperature Tc of the purification catalyst 135a reaches or exceeds the threshold value Tcref. A target equivalence ratio φ* and a target ignition timing IT* were set.

When the number of injection cylinders Nc is less than the threshold value Ncref in step S132, it is determined that the termination condition is not satisfied, and the process returns to step S120. In this way, the catalyst warm-up control catalyst rich control is continued. In this way, the processes of steps S120 to S132 are repeatedly executed, and when the number of injection cylinders Nc reaches the threshold value Ncref or more in step S132, it is determined that the termination condition is satisfied, and the catalyst warm-up control (catalyst rich control) is terminated. Then, this routine ends.

In the embodiment, the catalyst lean control and the catalyst rich control of the catalyst warm-up control are performed so that the termination condition is satisfied and the catalyst warm-up control is terminated when the temperature Tc of the purification catalyst 135a reaches or exceeds the threshold value Tcref. The target power Pe*, the target equivalence ratio φ*, the target ignition timing IT*, the transition condition (threshold OSref), and the end condition (threshold Ncref) are set.

As described above, in the embodiment, in the catalyst warm-up control, the catalyst lean control is executed based on the starting water temperature Twst and the first integrated air amount Qas1, and then the starting water temperature Twst and the second integrated air amount Qas2 are adjusted. Based on this, the catalyst richness is controlled. In the embodiment, when the oxygen storage amount OS reaches the threshold value OSref or more during execution of the catalyst lean control, the transition is made to the catalyst rich control. Variations occur in the first integrated air amount Qas1 (when starting rich control). For these reasons, when catalyst rich control is executed based on the first integrated air amount Qas1, it is difficult to appropriately set target power Pe*, target equivalence ratio φ*, and target ignition timing IT* in catalyst rich control. Therefore, there is a possibility that the engine 22 cannot be properly controlled. On the other hand, in the embodiment, by executing the catalyst rich control based on the second integrated air amount Qas2, the target power Pe*, the target equivalence ratio φ*, the target ignition timing IT* Since the engine 22 can be controlled by setting more appropriately, the engine 22 can be controlled more appropriately. As a result, catalyst rich control can be executed more appropriately.

FIG. 4 shows the rotational speed Ne of the engine 22, the temperature Tc of the purification catalyst 135a, whether or not catalyst warm-up control is executed, the first integrated air amount Qas1, the second integrated air amount Qas2, the target power Pe*, and the target equivalence ratio φ * is an explanatory diagram showing an example of the state of the target ignition timing IT*. As shown in the figure, when the temperature Tc of the purification catalyst 135a is less than the threshold Tcref at the time of completion of starting the engine 22 (time t11), the catalyst lean control in the catalyst warm-up control is executed, and the catalyst lean control is executed. When the oxygen storage amount OS reaches the threshold value OSref or more (time t12), the transition is made to catalyst rich control, and when the number of injection cylinders Nc reaches the threshold value Ncref or more during the execution of the catalyst rich control (time t13), the catalyst End warm-up control. In the catalyst lean control, the engine 22 is controlled by setting target power Pe*, target equivalence ratio φ*, and target ignition timing IT* based on the starting water temperature Twst and the first integrated air amount Qas1. In the catalyst rich control, the engine 22 is controlled by setting target power Pe*, target equivalence ratio φ*, and target ignition timing IT* based on the starting water temperature Twst and the second integrated air amount Qas2. In the catalyst rich control, by using the second integrated air amount Qas2, the engine 22 can be controlled more appropriately than when using the first integrated air amount Qas1. As a result, catalyst rich control can be executed more appropriately.

In the engine device 21 installed in the hybrid vehicle 20 of the embodiment described above, catalyst lean control and catalyst rich control are executed in this order in catalyst warm-up control. In the catalyst lean control, the engine 22 is controlled by setting target power Pe*, target equivalence ratio φ*, and target ignition timing IT* based on the starting water temperature Twst and the first integrated air amount Qas1. In the catalyst rich control, the engine 22 is controlled by setting target power Pe*, target equivalence ratio φ*, and target ignition timing IT* based on the starting water temperature Twst and the second integrated air amount Qas2. Thereby, in the catalyst rich control, the engine 22 can be controlled by setting target power Pe*, target equivalence ratio φ*, and target ignition timing IT* more appropriately. As a result, catalyst rich control can be executed more appropriately.

In the engine device 21 installed in the hybrid vehicle 20 of the embodiment, the engine 22 is controlled based on the starting water temperature Twst and the first integrated air amount Qas1 in the catalyst lean control, and the starting water temperature is controlled in the catalyst rich control. The engine 22 is controlled based on Twst and the second integrated air amount Qas2. However, in the catalyst lean control, the engine 22 is controlled based on the first integrated air amount Qas1 without considering the starting water temperature Twst, and in the catalyst rich control, the engine 22 is controlled based on the first integrated air amount Qas1 without considering the starting water temperature Twst. The engine 22 may be controlled based on the integrated air amount Qas2.

In the engine device 21 installed in the hybrid vehicle 20 of the embodiment, in the catalyst lean control, the target power Pe*, the target equivalence ratio φ*, and the target ignition timing IT are determined based on the starting water temperature Twst and the first integrated air amount Qas1. *, and in the catalyst rich control, the target power Pe*, the target equivalence ratio φ*, and the target ignition timing IT* are set based on the starting water temperature Twst and the second integrated air amount Qas2. However, in catalyst lean control, one of the target power Pe*, the target equivalence ratio φ*, and the target ignition timing IT* is set based on the starting water temperature Twst and the first integrated air amount Qas1. The remaining two may be set based on the following. In addition, in the catalyst rich control, one of the target power Pe*, the target equivalence ratio φ*, and the target ignition timing IT* is set based on the starting water temperature Twst and the second integrated air amount Qas2, and one of the target power Pe*, the target equivalence ratio φ*, and the target ignition timing IT* is set. The remaining two may be set based on the following.

In the engine device 21 installed in the hybrid vehicle 20 of the embodiment, in the catalyst lean control, the target power Pe*, the target equivalence ratio φ*, and the target ignition timing IT are determined based on the starting water temperature Twst and the first integrated air amount Qas1. *, and in the catalyst rich control, the target power Pe*, the target equivalence ratio φ*, and the target ignition timing IT* are set based on the starting water temperature Twst and the second integrated air amount Qas2. However, regarding catalyst lean control, at least one of the target power Pe*, target equivalence ratio φ*, and target ignition timing IT* is set based on the starting water temperature Twst and the first integrated air amount Qas1. Good to have. Furthermore, regarding the catalyst rich control, at least one of the target power Pe*, target equivalence ratio φ*, and target ignition timing IT* is set based on the starting water temperature Twst and the second integrated air amount Qas2. Good to have.

In the engine device 21 installed in the hybrid vehicle 20 of the embodiment, in the catalyst lean control, the target power Pe*, the target equivalence ratio φ*, and the target ignition timing IT are determined based on the starting water temperature Twst and the first integrated air amount Qas1. *, and in the catalyst rich control, the target power Pe*, the target equivalence ratio φ*, and the target ignition timing IT* are set based on the starting water temperature Twst and the second integrated air amount Qas2. However, in catalyst lean control, in addition to at least one of target power Pe*, target equivalence ratio φ*, and target ignition timing IT*, injection modes (port injection mode, in-cylinder injection mode, shared injection mode), injection timing, number of injections (in the case of multiple injections), supply fuel pressure of the in-cylinder injection valve 127, opening/closing timing of the intake valve 128 and exhaust valve 133 (when the engine 22 In the case where a variable valve timing device that can change the opening/closing timing of the valve 128 or the exhaust valve 133 is provided, at least one of the following may be set based on the starting water temperature Twst and the first integrated air amount Qas1. In addition, in catalyst rich control, in addition to at least one of target power Pe*, target equivalence ratio φ*, and target ignition timing IT*, in fuel injection control, injection mode, injection timing, number of injections, and in-cylinder injection At least one of the supply fuel pressure of the valve 127, the opening/closing timing of the intake valve 128 and the exhaust valve 133 (if a variable valve timing device is provided), etc. is set based on the starting water temperature Twst and the second integrated air amount Qas2. You can also use it as

In the engine device 21 installed in the hybrid vehicle 20 of the embodiment, a condition in which the oxygen storage amount OS reaches the threshold OSref or more is used as the transition condition. However, in addition to the condition (A1) in which the oxygen storage amount OS reaches the threshold value OSref or more, the condition (A2) in which the first integrated air amount Qas1 reaches the threshold value Qasref1 or more may be used as the transition condition. In this case, it may be determined that the transition condition is satisfied when either condition (A1) or (A2) is satisfied, or it may be determined that the transition condition is satisfied when both conditions (A1) and (A2) are satisfied. It may be determined that the condition is satisfied.

In the engine device 21 installed in the hybrid vehicle 20 of the embodiment, the condition in which the number of injection cylinders Nc reaches or exceeds the threshold value Ncref is used as the termination condition. However, as termination conditions, in addition to or in place of the condition (B1) in which the number of injection cylinders Nc has reached the threshold value Ncref or more, the condition (B2) in which the second integrated air amount Qas2 has reached the threshold value Qasref2 or more, or the condition (B2) in which the number of injection cylinders Nc has reached the threshold value Ncref or more, It is also possible to use a condition (B3) in which the temperature Tc of is equal to or higher than the threshold value Tcref. For example, when conditions (B1) to (B3) are used as termination conditions, it may be determined that the termination conditions are satisfied when any one of conditions (B1) to (B3) is satisfied; It may be determined that the termination condition is satisfied when all of the conditions (B1) to (B3) are satisfied.

In the engine device 21 installed in the hybrid vehicle 20 of the embodiment, when execution of exhaust restriction control is requested, execution of catalyst warm-up control is requested due to temperature Tc of purification catalyst 135a being less than threshold value Tcref. In addition to considering the case where the exhaust gas is restricted, the catalyst warm-up control is executed as the exhaust restriction control. However, if the execution of exhaust restriction control is required for a reason different from the case where execution of catalyst warm-up control is required (for example, the starting water temperature Twst is extremely low or extremely high), the exhaust restriction As the control, a control different from catalyst warm-up control may be executed. In this case, as the exhaust restriction control, for example, different control may be executed in that the optimum ignition timing is set as the target ignition timing IT* for the catalyst lean control and the catalyst rich control.

The engine device 21 installed in the hybrid vehicle 20 of the embodiment uses a four-cylinder engine 22. However, a 6-cylinder, 8-cylinder, or 12-cylinder engine may also be used.

The hybrid vehicle 20 of the embodiment includes an engine ECU 24, a motor ECU 40, a battery ECU 52, and an HVECU 70. However, at least two of these may be configured as a single electronic control unit.

In the embodiment, the engine device is installed in a hybrid vehicle 20 that includes an engine 22, a planetary gear 30, and motors MG1 and MG2. However, it may also be in the form of an engine device mounted on a so-called one-motor hybrid vehicle that includes an engine and one motor. Alternatively, the present invention may be in the form of an engine device that is mounted on a vehicle that does not include a motor for driving and runs using only power from the engine. Furthermore, it may be in the form of an engine device mounted on equipment that does not move, such as construction equipment.

The correspondence between the main elements of the embodiments and the main elements of the invention described in the column of means for solving the problems will be explained. In the embodiment, the engine 22 corresponds to an "engine," the purification catalyst 135a corresponds to a "purification catalyst," and the engine ECU 24 corresponds to a "control device."

The correspondence relationship between the main elements of the examples and the main elements of the invention described in the column of means for solving the problem is that the example implements the invention described in the column of means for solving the problem. Since this is an example for specifically explaining a form for solving the problem, it is not intended to limit the elements of the invention described in the column of means for solving the problems. In other words, the interpretation of the invention described in the column of means for solving the problem should be based on the description in that column, and the examples are based on the description of the invention described in the column of means for solving the problem. This is just one specific example.

Although the embodiments of the present invention have been described above using examples, the present invention is not limited to these examples in any way, and may be modified in various forms without departing from the gist of the present invention. Of course, it can be implemented.

INDUSTRIAL APPLICATION This invention can be utilized for the manufacturing industry of an engine device, etc.

20 Hybrid vehicle, 21 Engine device, 22 Engine, 23 Crankshaft, 24 Engine ECU, 28 Damper, 30 Planetary gear, 36 Drive shaft, 38 Differential gear, 39a, 39b Drive wheels, 40 Motor ECU, 41, 42 Inverter, 50 Battery , 52 battery ECU, 54 power line, 70 HVECU, 80 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 86 brake pedal position sensor, 88 vehicle speed sensor, 89 Outside temperature sensor, 122 Air cleaner, 123 Intake pipe, 123a Air flow meter, 123t Temperature sensor, 124 Throttle valve, 124a Throttle valve position sensor, 125 Surge tank, 125a Pressure sensor, 126 Port injection valve, 127 In-cylinder injection valve, 128 Intake valve, 129 combustion chamber, 130 spark plug, 132 piston, 133 exhaust valve, 134 exhaust pipe, 135 purification device, 135a purification catalyst, 137 front air-fuel ratio sensor, 138 rear air-fuel ratio sensor, 140 crank position sensor, 142 water temperature sensor, 144 Cam position sensor, MG1, MG2 motor.

Claims (1)

engine and
a purification catalyst that purifies the exhaust gas of the engine;
In the execution of exhaust restriction control that limits the displacement of the engine, lean control that controls the engine so that the equivalence ratio is smaller than a value 1, and lean control that controls the engine so that the equivalence ratio becomes larger than the value 1. a control device that executes the rich control to be controlled in this order;
An engine device comprising:
The control device includes:
In the lean control, at least one of a target output, a target equivalence ratio, and a target ignition timing is set based on a first integrated air amount that is an integrated value of the intake air amount from the start of the lean control, and the control the engine,
In the rich control, at least one of the target output, the target equivalence ratio, and the target ignition timing is set based on a second integrated air amount that is an integrated value of the intake air amount since the start of the rich control. to control the engine;
engine equipment.

Images