Vehicle

Abstract

To prevent engine output from being continuously limited to no avail.SOLUTION: A vehicle is configured to: calculate first and second total discharge amounts of particulate matters when assuming that an engine is continuously operated at first temporary upper limit output and second temporary upper limit output which is less than the first temporary upper limit output at the start of operating the engine; set the first and second total discharge amounts as first and second remaining discharge amounts; repeatedly execute update processing for updating the first remaining discharge amount by subtracting a first period discharge amount of the particulate matters when assuming that the engine is operated at the first temporary upper limit output from a previous value of the first remaining discharge amount and updating the second remaining discharge amount by subtracting a second period discharge amount of the particulate matters in actual operation of the engine from a previous value of the second remaining discharge amount; set the second temporary upper limit output to control upper limit output when a difference obtained by subtracting the first remaining discharge amount from the second remaining discharge amount is less than a difference threshold; and switch the control upper limit output to the first temporary upper limit output when the difference becomes equal to or larger than the difference threshold.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a vehicle.

Background Art

[0002] Conventionally, in a vehicle equipped with an engine having a catalyst for purifying exhaust gas attached to an exhaust system, when warm-up of the engine or the catalyst is required, when the required power required for the engine is equal to or less than a first power, the engine is controlled so that the engine is operated at a power equal to or less than the first power, and when the required power is greater than the first power, the engine is controlled so that the engine is operated at a power greater than the first power and equal to or less than a second power that is less than the maximum allowable output of the engine (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In such a vehicle, when it is required to suppress the emission of particulate matter such as soot from the engine, the engine is operated within a range equal to or less than a relatively small control upper limit output to suppress the emission of particulate matter. If the engine is operated at an output smaller than this control upper limit output and the integrated emission amount of particulate matter is not so large, there is a possibility that the control upper limit output will be unnecessarily maintained at a relatively small value and the output of the engine will be unnecessarily restricted.

[0005] The main object of the vehicle of the present invention is to suppress the continuous unnecessary restriction of the output of the engine.

Means for Solving the Problems

[0006] The vehicle of the present invention adopts the following means to achieve the above main object.

[0007] The vehicle of the present invention includes an engine and a control device that controls the engine so that the engine is operated within a range below the upper limit output for control, and is a vehicle capable of intermittently operating the engine. The control device calculates a first total emission amount of the particulate matter when it is assumed that the engine is continuously operated at a first provisional upper limit output at the start of operation of the engine, and calculates a second total emission amount of the particulate matter when it is assumed that the engine is continuously operated at a second provisional upper limit output less than the first provisional upper limit output, sets the first total emission amount as a first remaining emission amount, and sets the second total emission amount as a second remaining emission amount. The update process is repeatedly executed, in which a first period emission amount of the particulate matter when the engine is assumed to be operated at the first provisional upper limit output is subtracted from the previous value of the first remaining emission amount to update the first remaining emission amount, and a second period emission amount of the particulate matter in the actual operation of the engine is subtracted from the previous value of the second remaining emission amount to update the second remaining emission amount. When the difference obtained by subtracting the first remaining emission amount from the second remaining emission amount is less than a difference threshold value, the second provisional upper limit output is set as the upper limit output for control, and when the difference reaches the difference threshold value or more, the upper limit output for control is switched to the first provisional upper limit output. This is the gist.

[0008] In the vehicle of the present invention, the engine is controlled so as to be operated within a range below the upper limit output for control. In this case, at the start of engine operation, the first total emission amount of particulate matter is calculated when it is assumed that the engine is continuously operated at the first provisional upper limit output, and the second total emission amount of particulate matter is calculated when it is assumed that the engine is continuously operated at a second provisional upper limit output less than the first provisional upper limit output. The first total emission amount is set as the first remaining emission amount and the second total emission amount is set as the second remaining emission amount. Subsequently, the update process is repeatedly executed in which the first period emission amount of particulate matter when it is assumed that the engine is operated at the first provisional upper limit output is subtracted from the previous value of the first remaining emission amount to update the first remaining emission amount, and the second period emission amount of particulate matter in the actual operation of the engine is subtracted from the previous value of the second remaining emission amount to update the second remaining emission amount. Then, when the difference obtained by subtracting the first remaining emission amount from the second remaining emission amount is less than the difference threshold, the second provisional upper limit output is set as the upper limit output for control, and when the difference reaches the difference threshold or more, the upper limit output for control is switched to the first provisional upper limit output. Thereby, when the engine is operated at a relatively low output compared to the second provisional upper limit output (the sequential second period emission amounts are relatively small) and the second remaining emission amount decreases relatively gently, the difference easily reaches the difference threshold or more early, and the upper limit output for control can be easily switched to the first provisional upper limit output early. As a result, it is possible to suppress continuously and wastefully limiting the output of the engine.

[0009] In the vehicle of the present invention, when the first integrated air amount in the current trip is equal to or more than the first threshold value, or when the second integrated air amount in the current engine operation is equal to or more than the second threshold value, the first provisional upper limit output may be set as the upper limit output for control regardless of the difference.

[0010] In the vehicle of the present invention, the control device may set the first provisional upper limit output based on the water temperature at the first start of the engine in the current trip, and set the second provisional upper limit output based on the water temperature at the current start of the engine.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

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Figure 5

Figure 6

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Figure 11

Figure 12

Embodiments for Carrying Out the Invention

[0012] Next, embodiments for carrying out the present invention will be described using examples.

Examples

[0013] FIG. 1 is a configuration diagram showing an outline of the configuration of a hybrid vehicle 20 as an embodiment of the present invention, and FIG. 2 is a configuration diagram showing an outline of the configuration of the engine 22. As shown in FIG. 1, the hybrid vehicle 20 of the embodiment includes an engine 22, 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.

[0014] The engine 22 is configured as an internal combustion engine that outputs power through four strokes of intake, compression, expansion (explosion combustion), and exhaust using fuel such as gasoline or light oil. As shown in FIG. 2, the engine 22 has a port injection valve 125 that injects fuel into the intake port and an in-cylinder injection valve 126 that injects fuel into the cylinder. By having the port injection valve 125 and the in-cylinder injection valve 126, the engine 22 can be operated in any one of a port injection mode, an in-cylinder injection mode, and a common injection mode.

[0015] In the port injection mode, the air cleaned by the air cleaner 122 is inhaled into the intake pipe 123, passed through the throttle valve 124, and fuel is injected from the port injection valve 125 to mix the air and fuel. Then, this air-fuel mixture is inhaled into the combustion chamber 129 through the intake valve 128, and is explosively combusted by the electric spark from the spark plug 130. The energy generated by this explosive combustion converts the reciprocating motion of the piston 132 pushed down in the cylinder bore 131 into the rotational motion of the crankshaft 23. In the in-cylinder injection mode, air is inhaled into the combustion chamber 129 in the same manner as in the port injection mode, fuel is injected from the in-cylinder injection valve 126 during the intake stroke and the compression stroke, and is explosively combusted by the electric spark from the spark plug 130 to obtain the rotational motion of the crankshaft 23. In the common injection mode, fuel is injected from the port injection valve 125 when air is inhaled into the combustion chamber 129, and fuel is injected from the in-cylinder injection valve 126 during the intake stroke and the compression stroke, and is explosively combusted by the electric spark from the spark plug 130 to obtain the rotational motion of the crankshaft 23. These injection modes are switched based on the operating state of the engine 22 and the like. The exhaust discharged from the combustion chamber 129 to the exhaust pipe 134 through the exhaust valve 133 is discharged to the outside air through the purification device 135. The purification device 135 has a purification catalyst (three-way catalyst) 135a that purifies harmful components such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx) in the exhaust. Note that the purification catalyst 135a may be a four-way catalyst that combines the purification function of the three-way catalyst and the collection function of collecting particulate matter (PM) such as soot in the exhaust.

[0016] The engine 22 further includes a variable valve timing device 150. The variable valve timing device 150 is configured to be able to continuously change the opening and closing timings of the intake valve 128 and the exhaust valve 133, respectively.

[0017] The engine 22 is operationally controlled by an engine electronic control unit (hereinafter referred to as "engine ECU") 24. The engine ECU 24 includes a microcomputer having a CPU, ROM, RAM, flash memory, input / output ports, and communication ports, although not shown in the figure. Signals from various sensors necessary for operationally controlling the engine 22 are input to the engine ECU 24 via the input ports. Examples of signals input to the engine ECU 24 include the crank angle θcr from a crank position sensor 140 that detects the rotational position of the crankshaft 23 of the engine 22, and the coolant temperature Tw from a water temperature sensor 142 that detects the temperature of the coolant of the engine 22. Also included are the 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. Further examples include the throttle opening TH from a throttle valve position sensor 124a that detects the position of the throttle valve 124, the intake air quantity Qa from an air flow meter 123a attached upstream of the throttle valve 124 in the intake pipe 123, and the intake air temperature Ta from a temperature sensor 123t attached upstream of the throttle valve 124 in the intake pipe 123. Also included are the front air-fuel ratio AFf from a front air-fuel ratio sensor 137 attached upstream of the purification device 135 in the exhaust pipe 134, and the rear air-fuel ratio AFr from a rear air-fuel ratio sensor 138 attached downstream of the purification device 135 in the exhaust pipe 134.

[0018] Various control signals for operationally controlling the engine 22 are output from the engine ECU 24 via the output ports. Examples of signals output from the engine ECU 24 include a control signal to the throttle valve 124, a control signal to the port injection valve 125, a control signal to the in-cylinder injection valve 126, a control signal to the ignition plug 130, and a control signal to the variable valve timing device 150.

[0019] The engine ECU 24 is connected to the HV ECU 70 via a communication port. The engine ECU 24 calculates the engine speed Ne of the engine 22 based on the crank angle θcr of the engine 22 from the crank position sensor 140. Further, the engine ECU 24 calculates a load factor KL (the ratio of the volume of air actually inhaled in one cycle to the stroke volume per cycle of the engine 22) based on the intake air volume Qa from the air flow meter 123a and the engine speed Ne of the engine 22. Additionally, the engine ECU 24 calculates the opening and closing timings VTi, VTo of the intake valve 128 and the exhaust valve 133 based on the angles (θci - θcr), (θco - θcr) of the cam angles θci, θco of the intake camshaft and the exhaust camshaft from the cam position sensor 144 with respect to the crank angle θcr. Moreover, the engine ECU 24 estimates the temperature Tc of the purification catalyst 135a of the purification device 135 based on the coolant temperature Tw from the coolant temperature sensor 142, the engine speed Ne of the engine 22, the load factor KL, and the ignition timing.

[0020] As shown in FIG. 1, the planetary gear 30 is configured as a single pinion type planetary gear mechanism. The rotor of the motor MG1 is connected to the sun gear of the planetary gear 30. The drive shaft 36, which is connected to the drive wheels 39a, 39b via the differential gear 38, is connected to the ring gear of the planetary gear 30. The crankshaft 23 of the engine 22 is connected to the carrier of the planetary gear 30.

[0021] The motor MG1 is configured as, for example, a synchronous generator motor, and as described above, the rotor is connected to the sun gear of the planetary gear 30. The motor MG2 is configured as, for example, a synchronous generator motor, and the rotor is connected to the drive shaft 36. The inverters 41, 42 are used to drive the motors MG1, MG2 and are connected to the battery 50 via the power line 54. The motors MG1, MG2 are rotationally driven by the motor electronic control unit (hereinafter referred to as "motor ECU") 40 by switching control of a plurality of switching elements (not shown) of the inverters 41, 42.

[0022] The motor ECU 40 includes a microcomputer having a CPU, a ROM, a RAM, a flash memory, input / output ports, and communication ports, although not shown in the figure. Signals from various sensors necessary for driving and controlling the motors MG1 and MG2 are input to the motor ECU 40 via the input ports. Examples of the signals input to the motor ECU 40 include the rotational positions θm1 and θm2 from a rotational position sensor (not shown) that detects the rotational positions of the rotors of the motors MG1 and MG2, and the phase currents Iu1, Iv1, Iu2, and Iv2 from a current sensor (not shown) that detects the phase currents flowing through each phase of the motors MG1 and MG2. Switching control signals and the like to a plurality of switching elements (not shown) of the inverters 41 and 42 are output from the motor ECU 40 via the output ports. The motor ECU 40 is connected to the HV ECU 70 via the communication port. The motor ECU 40 calculates the electrical angles θe1 and θe2 and the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 based on the rotational positions θm1 and θm2 of the rotors of the motors MG1 and MG2 from the rotational position sensor.

[0023] 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.

[0024] The battery ECU 52 includes a microcomputer having a CPU, ROM, RAM, flash memory, input / output ports, and communication ports, although not shown in the figure. Signals from various sensors necessary for managing the battery 50 are input to the battery ECU 52 via the input ports. Examples of the signals input to the battery ECU 52 include the voltage Vb of the battery 50 from a voltage sensor (not shown) attached between the terminals of the battery 50, the current Ib of the battery 50 from a current sensor (not shown) attached to the output terminal of the battery 50, and the temperature Tb of the battery 50 from a temperature sensor (not shown) attached to the battery 50. The battery ECU 52 is connected to the HV ECU 70 via a communication port. The battery ECU 52 calculates the state of charge SOC of the battery 50 based on the integrated value of the current Ib of the battery 50 from the current sensor. The state of charge SOC is the ratio of the amount of electric power that can be discharged from the battery 50 to the total capacity of the battery 50.

[0025] The HV ECU 70 includes a microcomputer having a CPU, ROM, RAM, flash memory, input / output ports, and communication ports, although not shown in the figure. Signals from various sensors are input to the HV ECU 70 via the input ports. Examples of the signals input to the HV ECU 70 include the ignition signal from the ignition switch 80 and the shift position SP from the shift position sensor 82 that detects the operation position of the shift lever 81. Also, the accelerator opening Acc from the accelerator pedal position sensor 84 that detects the depression amount of the accelerator pedal 83, the brake pedal position BP from the brake pedal position sensor 86 that detects the depression amount of the brake pedal 85, and the vehicle speed V from the vehicle speed sensor 87 can be mentioned. As described above, the HV ECU 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via communication ports.

[0026] In the hybrid vehicle 20 of the embodiment configured in this way, basically, by the cooperative control of the HVECU 70, the engine ECU 24, and the motor ECU 40, there are a hybrid driving mode (HV driving mode) in which the vehicle travels with the operation of the engine 22 and an electric driving mode (EV driving mode) in which the vehicle travels without the operation of the engine 22. The engine 22 is intermittently operated while switching between these modes to drive the vehicle.

[0027] In the HV driving mode, the HVECU 70 sets the driving torque Td* required for driving (required for the drive shaft 36) based on the accelerator opening Acc and the vehicle speed V, and multiplies the set driving torque Td* by the rotational speed Nd of the drive shaft 36 (the rotational speed Nm2 of the motor MG2) to calculate the driving power Pd* required for driving. Subsequently, based on the driving power Pd* and the state of charge SOC of the battery 50, a temporary target power Petmp, which is a temporary value of the target power Pe* of the engine 22, is set, and the set temporary target power Petmp is limited (upper limit guard) by the control upper limit power Pelim (control upper limit output) to set the target power Pe*. The method for setting the control upper limit power Pelim will be described later. Then, the target rotational speed Ne* and target torque Te* of the engine 22 and the torque commands Tm1*, Tm2* of the motors MG1, MG2 are set so that the target power Pe* is output from the engine 22 and the driving torque Td* is output to the drive shaft 36. The set target rotational speed Ne* and target torque Te* are transmitted to the engine ECU 24, and the torque commands Tm1*, Tm2* are transmitted to the motor ECU 40.

[0028] The engine ECU 24 performs operation control of the engine 22, such as intake air amount control, fuel injection control, ignition control, and opening / closing timing control, so that the engine 22 operates based on the target rotational speed Ne* and the target torque Te*. The intake air amount control is performed by controlling the opening degree of the throttle valve 124. The fuel injection control is performed by controlling the fuel injection amount from the port injection valve 125 or the in-cylinder injection valve 126 in the port injection mode, the in-cylinder injection mode, or the common injection mode. The ignition control is performed by controlling the ignition timing of the spark plug 130. The opening / closing timing control is performed by controlling the opening / closing timing of the intake valve 128 and the exhaust valve 133 by the variable valve timing device 150. The motor ECU 40 performs switching control of a plurality of switching elements of the inverters 41 and 42 so that the motors MG1 and MG2 are driven by the torque commands Tm1* and Tm2*.

[0029] In the EV driving mode, the HV ECU 70 sets the driving torque Td* in the same manner as in the HV driving mode, sets the value 0 for the torque command Tm1* of the motor MG1, and sets the torque command Tm2* of the motor MG2 so that the driving torque Td* is output to the drive shaft 36, and transmits the set torque commands Tm1* and Tm2* to the motor ECU 40. The control of the inverters 41 and 42 by the motor ECU 40 has been described above.

[0030] In the HV driving mode, when the temporary target power Petmp reaches less than the threshold value Peref, etc., it is determined that the stop condition of the engine 22 is satisfied, the engine 22 is stopped, and the vehicle shifts to the EV driving mode. In the EV driving mode, when the temporary target power Petmp calculated in the same manner as in the HV driving mode reaches the power threshold value Peref or more, etc., it is determined that the start condition of the engine 22 is satisfied, the engine 22 is started, and the vehicle shifts to the HV driving mode.

[0031] Next, the operation of the hybrid vehicle 20 of the thus configured embodiment will be described, particularly the setting process of the control upper limit power Pelim. FIGS. 3 and 4 are flowcharts showing an example of the control upper limit power setting routine executed by the HVECU 70. This routine is repeatedly executed when the engine 22 is operating.

[0032] When the control upper limit power setting routine in FIGS. 3 and 4 is executed, the HVECU 70 first inputs data such as the water temperature Twst1 at the first start of the engine 22, the water temperature Twst2 at the current start, the trip integrated air amount Iqa1 (first integrated air amount), the current integrated air amount Iqa2 (second integrated air amount), and the actual output Peac (step S100). Here, the water temperature Twst1 at the first start and the water temperature Twst2 at the current start are respectively the cooling water temperature Tw detected by the water temperature sensor 142 at the first start and the current start of the engine 22 in the current trip. The trip integrated air amount Iqa1 is the integrated air amount in the current trip, and a value calculated as the integrated value of the intake air amount Qa detected by the air flow meter 123a from the start of the first operation of the engine 22 in the current trip is input. The current integrated air amount Iqa2 is the integrated air amount in the current operation of the engine 22 (from the start of the current operation of the engine 22 to the end of the operation), and a value calculated as the integrated value of the intake air amount Qa detected by the air flow meter 123a from the start of the current operation of the engine 22 is input. The actual output Peac is the output in the actual operation of the engine 22, and a value estimated based on the engine speed Ne, the load factor KL (intake air amount Qa), the ignition timing, etc. of the engine 22 is input.

[0033] Subsequently, in the operation of the engine 22 this time, it is determined whether this is the first execution of this routine (step S110). When it is determined that this is the first execution of this routine in the operation of the engine 22 this time, the value 0 is set in the upper limit release flag Fpe (step S120), and the provisional upper limit power Pe1 (first provisional upper limit output) is set based on the water temperature Twst1 at the first start (step S130), and the provisional upper limit power Pe2 (second provisional upper limit output) is set based on the water temperature Twst2 at the current start (step S140). Here, the details of the upper limit release flag Fpe will be described later. The provisional upper limit power Pe1 is the upper limit power set so as to ensure the running performance of the vehicle. This provisional upper limit power Pe1 can be set, for example, by applying the water temperature Twst1 at the first start to a first provisional upper limit output setting map in which the relationship between the water temperature Twst1 at the first start and the provisional upper limit power Pe1 is determined in advance by experiments, analysis, machine learning, etc. The provisional upper limit power Pe1 is set so as to be higher as the water temperature Twst1 at the first start is higher. The provisional upper limit power Pe2 is the upper limit power set so that the total emission amount of particulate matter (particulate number (PN)) Spn2 described later becomes equal to or less than the allowable amount Spnlim in the operation of the engine 22 this time. This provisional upper limit power Pe2 can be set, for example, by applying the water temperature Twst2 at the current start to a second provisional upper limit output setting map in which the relationship between the water temperature Twst2 at the current start and the provisional upper limit power Pe2 is determined in advance by experiments, analysis, machine learning, etc. The provisional upper limit power Pe2 is set so as to be higher as the water temperature Twst2 at the current start is higher.

[0034] Then, the total emission amount Spn1 of particulate matter is calculated based on the temporary upper limit power Pe1 (step S150), and the total emission amount Spn2 of particulate matter is calculated based on the temporary upper limit power Pe2 (step S160). Here, the total emission amount Spn1 (the first total emission amount) is an estimated value of the total emission amount (total number of particulate matters) of particulate matter when it is assumed that the engine 22 is continuously operated at the temporary upper limit power Pe1 in the current operation of the engine 22. The total emission amount Spn2 (the second total emission amount) is an estimated value of the total emission amount of particulate matter when it is assumed that the engine 22 is continuously operated at the temporary upper limit power Pe2 in the current operation of the engine 22. FIG. 5 is an explanatory diagram showing an example of the relationship between the trip integrated air amount Iqa1, the current integrated air amount Iqa2, the output Pe of the engine 22, and the number of particulate matters Npn per unit time. When the trip integrated air amount Iqa1, the current integrated air amount Iqa2, the output Pe, and the number of particulate matters Npn have the relationship as shown in FIG. 5, the total emission amount Spn1 can be calculated by applying the temporary upper limit power Pe1 to the output Pe and integrating in the range of the input value in step S100 or more for the trip integrated air amount Iqa1. The total emission amount Spn2 can be calculated by applying the temporary upper limit power Pe2 to the output Pe and integrating in the range of the input value in step S100 or more for the current integrated air amount Iqa2. For example, when the temporary upper limit power Pe1 is the output Pe of the value Pe6 and the input value of the trip integrated air amount Iqa1 is the value Iqa1ini, the area surrounded by the thick solid line in FIG. 5 can be calculated as the total emission amount Spn1. Also, when the temporary upper limit power Pe2 is the output Pe of the value Pe3 and the input value of the current integrated air amount Iqa2 is the value 0, the area surrounded by the thick dashed line in FIG. 5 can be calculated as the total emission amount Spn2.

[0035] In addition, the total emission amount Spn1 is set as the remaining emission amount Rpn1 (the first remaining emission amount) of particulate matter (step S170), and the total emission amount Spn2 is set as the remaining emission amount Rpn2 (the second remaining emission amount) of particulate matter (step S180). Also, the value 0 is set for the allowable emission amount Apn of particulate matter (step S190).

[0036] When it is determined in step S110 that this is not the first execution of this routine in the current operation of engine 22 (i.e., it is the second or subsequent execution), the period emission amount Qpn1 of particulate matter is calculated based on the previous value and the latest value of the provisional upper limit power Pe1 and the trip integrated air amount Iqa1 (step S200). Also, the period emission amount Qpn2 of particulate matter is calculated based on the previous value and the latest value of the provisional upper limit power Pe2 and the current integrated air amount Iqa2 (step S210). Further, the period emission amount Qpn3 of particulate matter is calculated based on the actual output Peac of engine 22 and the previous value and the latest value of the current integrated air amount Iqa2 (step S220). Here, the period emission amount Qpn1 (the first period emission amount) is the emission amount of particulate matter when it is assumed that engine 22 is operated at the provisional upper limit power Pe1 while the trip integrated air amount Iqa1 changes from the previous value to the latest value. The period emission amount Qpn2 is the emission amount of particulate matter when it is assumed that engine 22 is operated at the provisional upper limit power Pe2 while the current integrated air amount Iqa2 changes from the previous value to the latest value. The period emission amount Qpn3 (the second period emission amount) is the emission amount of particulate matter when it is assumed that engine 22 is operated at the actual output Peac while the current integrated air amount Iqa2 changes from the previous value to the latest value. When the trip integrated air amount Iqa1, the current integrated air amount Iqa2, the output Pe, and the number of particulate matter Npn are in the relationship shown in FIG. 5, the period emission amount Qpn1 can be calculated by applying the provisional upper limit power Pe1 to the output Pe and integrating the trip integrated air amount Iqa1 within the range from the previous value to the latest value. The period emission amount Qpn2 can be calculated by applying the provisional upper limit power Pe2 to the output Pe and integrating the current integrated air amount Iqa2 within the range from the previous value to the latest value. The period emission amount Qpn3 can be calculated by applying the actual output Peac to the output Pe and integrating the current integrated air amount Iqa2 within the range from the previous value to the latest value.

[0037] Subsequently, the remaining discharge amount Rpn1 of particulate matter is calculated by subtracting the period discharge amount Qpn1 from the previous remaining discharge amount (previous Rpn1) of particulate matter (step S230), and the remaining discharge amount Rpn2 of particulate matter is calculated by subtracting the period discharge amount Qpn3 from the previous remaining discharge amount (previous Rpn2) of particulate matter (step S240). Also, the margin discharge amount Apn is calculated by adding the value obtained by subtracting the period discharge amount Qpn3 from the period discharge amount Qpn2 of particulate matter to the previous margin discharge amount (previous Apn) (step S250). FIG. 6 is an explanatory diagram showing an example of the relationship between the trip integrated air amount Iqa1, the current integrated air amount Iqa2, the output Pe of the engine 22, and the number Npn of particulate matter per unit time, similar to FIG. 5. For example, the region surrounded by the thick solid line in FIG. 6 can be calculated as the remaining discharge amount Rpn1. Also, the region surrounded by the thick broken line in FIG. 6 can be calculated as the remaining discharge amount Rpn2. Further, the region surrounded by the thick dashed-dotted line in FIG. 6 (the region of the region surrounded by the thick broken line that is less than or equal to the latest value of the current integrated air amount Iqa2) can be calculated as the margin discharge amount Apn.

[0038] Thus, when the remaining discharge amount Rpn1, the remaining discharge amount Rpn2, and the margin discharge amount Apn of particulate matter are set or calculated in the processes of steps S170 to S190 or the processes of steps S230 to S250, the value of the upper limit release flag Fpe is examined (step S260). Then, when the upper limit release flag Fpe has a value of 0, the remaining discharge amount Rpn2 of particulate matter is compared with the remaining discharge amount Rpn1 (step S270). This process is a process for predicting whether or not the integrated discharge amount of particulate matter in the current operation of the engine 22, that is, the integrated value of the period discharge amount Qpn3, may become larger than the allowable amount Spnlim when performing the upper limit release process for releasing the control upper limit power Pelim to the temporary upper limit power Pe1. Although details will be described later, when performing the upper limit release process, the temporary upper limit power Pe1 is set to the control upper limit power Pelim, and when not performing the upper limit release process, a value less than the temporary upper limit power Pe1, specifically, a value obtained by multiplying the temporary upper limit power Pe2 by a coefficient kpe greater than 1 is set to the control upper limit power Pelim.

[0039] When the remaining emission amount Rpn2 is less than the remaining emission amount Rpn1 in step S270, it is predicted that if the upper limit release process is executed, the integrated emission amount of particulate matter in the current operation of the engine 22 may exceed the allowable amount Spnlim, and the upper limit release flag Fpe is held at the value 0. When the remaining emission amount Rpn2 is greater than or equal to the remaining emission amount Rpn1 in step S270, it is predicted that the probability that the integrated emission amount of particulate matter in the current operation of the engine 22 will exceed the allowable amount Spnlim is sufficiently low even if the upper limit release process is executed, and the upper limit release flag Fpe is switched from the value 0 to the value 1 (step S280). When the upper limit release flag Fpe has the value 1 in step S260, the upper limit release flag Fpe is held at the value 1. The upper limit release flag Fpe is a flag indicating whether to perform the upper limit release process based on the fact that the remaining emission amount Rpn2 is greater than or equal to the remaining emission amount Rpn1.

[0040] Subsequently, a threshold value Iqaref2 is set based on the current starting water temperature Twst2 (step S290). The trip integrated air amount Iqa1 is compared with the threshold value Iqaref11 (step S300), and the current integrated air amount Iqa2 is compared with the threshold value Iqaref2 which is less than the threshold value Iqaref11 (step S310). Here, both the threshold value Iqaref11 and the threshold value Iqaref2 are threshold values used to determine whether the warm-up of the combustion chamber 129 of the engine 22 is insufficient (incomplete) and whether a PN suppression requirement for suppressing the emission amount of particulate matter is being performed. A fixed value is used for the threshold value Iqaref11. The threshold value Iqaref2 can be set, for example, by applying the current starting water temperature Twst2 to a first threshold value setting map determined in advance by experiments, analysis, machine learning, etc. regarding the relationship between the current starting water temperature Twst2 and the threshold value Iqaref2. FIG. 7 is an explanatory diagram showing an example of the first threshold value setting map. As shown in the figure, the threshold value Iqaref2 is set to increase as the current starting water temperature Twst2 decreases. This is based on the fact that the lower the current starting water temperature Twst, the more difficult it is for the fuel injected from the port injection valve 125 and the in-cylinder injection valve 126 to vaporize, and the more likely the emission amount of particulate matter is to increase.

[0041] When the trip integrated air quantity Iqa1 is greater than or equal to the threshold value Iqaref11 in step S300, or when the current integrated air quantity Iqa2 is greater than or equal to the threshold value Iqaref2 in step S310, it is determined that the PN suppression request is not being made. The temporary upper limit power Pe1 is set to the control upper limit power Pelim (step S410), the value 0 is set to the PN suppression request flag Fpn (step S420), and this routine ends. Here, the PN suppression request flag Fpn is a flag indicating whether or not a PN suppression request, which is a request for suppressing the emission of particulate matter from the engine 22, is being made. In this case, the HVECU 70 sets the target power Pe* of the engine 22 within the range of the control upper limit power Pelim (=Pe1), and sets the target rotational speed Ne* and the target torque Te* of the engine 22 based on the target power Pe*. Also, when the PN suppression request flag Fpn has the value 0, the engine ECU 24 determines that the PN suppression request is not being made, and performs operation control of the engine 22 (hereinafter referred to as "normal operation control") in consideration of fuel consumption, fuel dilution, emissions, drivability, etc. based on the target rotational speed Ne* and the target torque Te*.

[0042] When the trip integrated air quantity Iqa1 is less than the threshold value Iqaref11 in step S300 and the current integrated air quantity Iqa2 is less than the threshold value Iqaref2 in step S310, it is determined that the PN suppression request is being made, and the value of the upper limit release flag Fpe is checked (step S320). When the upper limit release flag Fpe has the value 0, it is determined that the upper limit release process is not requested, the threshold value Iqaref12 is set within the range less than the threshold value Iqaref11 based on the initial start water temperature Twst1 (step S330), and the value obtained by multiplying the total emission amount Spn2 by the coefficient kpn is set to the threshold value Apnref (step S340). Subsequently, the trip integrated air quantity Iqa1 is compared with the threshold value Iqaref12 (step S350), and the margin emission amount Apn of the particulate matter is compared with the threshold value Apnref (step S360).

[0043] Here, the threshold Iqaref12 and the threshold Apnref are thresholds used to determine whether to execute an upper limit relaxation process that increases the control upper limit power Pelim with respect to the temporary upper limit power Pe2 within a range where the control upper limit power Pelim is less than the temporary upper limit power Pe1. The threshold Iqaref12 can be set, for example, by applying the initial start water temperature Twst1 to a second threshold setting map in which the relationship between the initial start water temperature Twst1 and the threshold Iqaref12 is determined in advance by experiments, analysis, machine learning, or the like. FIG. 8 is an explanatory diagram showing an example of the second threshold setting map. As shown in the figure, the threshold Iqaref12 is set such that it increases as the initial start water temperature Twst1 decreases. This is for the same reason as the tendency of the threshold Iqaref2 with respect to the current start water temperature Twst2. The coefficient kpn used for setting the threshold Apnref is, for example, about 0.05 to 0.10.

[0044] When the trip integrated air quantity Iqa1 is less than the threshold value Iqaref12 in step S350 or when the margin discharge amount Apn of particulate matter is less than the threshold value Apnref in step S360, it is determined that the upper limit relaxation process is not executed, the temporary upper limit power Pe2 is set to the control upper limit power Pelim (step S370), the value 1 is set to the PN suppression request flag Fpn (step S400), and this routine is terminated. In this case, the HVECU70 sets the target power Pe* of the engine 22 within the range of the control upper limit power Pelim (=Pe2) or less, and sets the target engine speed Ne* and the target torque Te* based on the target power Pe*. Further, when the PN suppression request flag Fpn has the value 1, the engine ECU24 determines that the PN suppression request is being made, and injects fuel from the in-cylinder injection valve 126 in the intake stroke a plurality of times (for example, once in the first half and once in the second half of the intake stroke) in the in-cylinder injection mode or the common injection mode to perform the operation control of the engine 22 (hereinafter referred to as "PN suppression operation control"). As a result, it is possible to shorten the injection length of the fuel injected from the in-cylinder injection valve 126 and suppress this fuel from hitting the cylinder bore 131 or the piston 132, or to secure the atomization time of this fuel. Therefore, by restricting the output Pe of the engine 22 or by injecting fuel from the in-cylinder injection valve 126 in the intake stroke a plurality of times in the in-cylinder injection mode or the common injection mode, the emission amount of particulate matter can be suppressed.

[0045] When the trip integrated air quantity Iqa1 is greater than or equal to the threshold value Iqaref12 in step S350 and the margin emission amount Apn of particulate matter is greater than or equal to the threshold value Apnref in step S360, it is determined that the upper limit relaxation process is to be executed. A coefficient kpe is set within a range greater than 1 based on the margin emission amount Apn of particulate matter (step S380). A value obtained by multiplying the provisional upper limit power Pe2 by the coefficient kpe is set as the control upper limit power Pelim (step S390). A value 1 is set for the PN suppression request flag Fpn (step S400), and this routine is terminated. In this case, the HVECU 70 sets the target power Pe* of the engine 22 within a range less than or equal to the control upper limit power Pelim (=Pe2·kpn), and sets the target engine speed Ne* and the target torque Te* based on the target power Pe*. Thus, as the upper limit relaxation process, by increasing the control upper limit power Pelim with respect to the provisional upper limit power Pe2, it is possible to achieve a certain degree of compatibility between the suppression of particulate matter emissions from the engine 22 and the increase in the output of the engine 22. That is, when the suppression of particulate matter emissions from the engine 22 is required, it is possible to prevent continuously restricting the output of the engine 22 unnecessarily. Moreover, when the trip integrated air quantity Iqa1 is greater than or equal to the threshold value Iqaref12 and the margin emission amount Apn of particulate matter is greater than or equal to the threshold value Apnref, by executing the upper limit relaxation process, it is possible to prevent executing the upper limit relaxation process when the trip integrated air quantity Iqa1 is less than the threshold value Iqaref12, for example, immediately after the start of the first operation of the engine 22 during a trip.

[0046] Here, the coefficient kpe can be set by applying the margin discharge amount Apn of particulate matter to a coefficient setting map determined in advance by experiments, analysis, machine learning, etc. for the relationship between the margin discharge amount Apn of particulate matter and the coefficient kpe. FIG. 9 is an explanatory diagram showing an example of the coefficient setting map. As shown in the figure, the coefficient kpe is set such that the larger the margin discharge amount Apn of particulate matter, the larger it becomes with respect to the value 1 within the range where the value obtained by multiplying the provisional upper limit power Pe2 by the coefficient kpe is less than the provisional upper limit power Pe1. Thereby, the larger the margin discharge amount Apn of particulate matter, the larger the control upper limit power Pelim can be made, and the output Pe of the engine 22 can be increased.

[0047] As the upper limit relaxation process, when the control upper limit power Pelim is increased with respect to the provisional upper limit power Pe2, the output Pe of the engine 22 may become larger than the provisional upper limit power Pe2. In this case, since the period discharge amount Qpn3 of particulate matter becomes larger than the period discharge amount Qpn2 of particulate matter in steps S210 and S230, the margin discharge amount Apn of particulate matter decreases in step S250. Thereby, the coefficient kpn becomes smaller and the control upper limit power Pelim becomes smaller. Then, when the margin discharge amount Apn of particulate matter reaches less than the threshold value Apnref in step S360, the provisional upper limit power Pe2 is set to the control upper limit power Pelim in step S370. In this way, the upper limit relaxation process is terminated.

[0048] When the trip integrated air quantity Iqa1 is less than the threshold value Iqaref11 in step S300 and the current integrated air quantity Iqa2 is less than the threshold value Iqaref2 in step S310, and when the upper limit release flag Fpe has the value 1 in step S320, it is determined that an upper limit release process is required based on the remaining emission amount Rpn2 being greater than or equal to the remaining emission amount Rpn1. As the upper limit release process, the temporary upper limit power Pe1 is set to the control upper limit power Pelim (step S410), the PN suppression request flag Fpn is set to the value 0 (step S420), and this routine is terminated. As described above, when the remaining emission amount Rpn2 of particulate matter reaches or exceeds the remaining emission amount Rpn1, the upper limit release flag Fpe is switched from the value 0 to the value 1. At this time, as the upper limit release process, the control upper limit power Pelim is switched from the temporary upper limit power Pe2 or the value obtained by multiplying this by the coefficient kpe to the temporary upper limit power Pe1. As a result, compared with the case where the upper limit release process is executed only when the trip integrated air quantity Iqa1 reaches or exceeds the threshold value Iqaref11 or when the current integrated air quantity Iqa2 reaches or exceeds the threshold value Iqaref2, there may be a case where the upper limit release process can be performed earlier. For example, when the actual output Peac of the engine 22 is relatively low compared to the temporary upper limit power Pe2 (the period emission amount Qpn3 of particulate matter is relatively small) and the remaining emission amount Rpn2 decreases relatively gently, the remaining emission amount Rpn2 is likely to reach or exceed the remaining emission amount Rpn1 earlier, and the control upper limit power Pelim can be easily switched to the temporary upper limit power Pe1 earlier. As a result, it is possible to suppress continuously and uselessly restricting the output Pe of the engine 22.

[0049] FIG. 10 is a time chart showing an example of the relationship between the trip integrated air quantity Iqa1, the remaining emissions Rpn1, Rpn2, the margin emissions Apn, and the control upper limit power Pelim. As shown in the figure, when the temporary upper limit power Pe2 is set for the control upper limit power Pelim, when the trip integrated air quantity Iqa1 reaches a value equal to or greater than the threshold Iqaref12 and the margin emissions Apn reaches a value equal to or greater than the threshold Apnref (at time t1), as an upper limit relaxation process, the control upper limit power Pelim is increased with respect to the temporary upper limit power Pe2. Then, when the upper limit relaxation process is being executed and the margin emissions Apn reaches a value less than the threshold Apnref, as the end of the upper limit relaxation process, the control upper limit power Pelim is decreased with respect to the temporary upper limit power Pe2. After that, when the remaining emissions Rpn2 reaches a value equal to or greater than the remaining emissions Rpn1 (at time t3), as an upper limit release process, the control upper limit power Pelim is increased to the temporary upper limit power Pe1.

[0050] In the hybrid vehicle 20 of the embodiment described above, when starting the operation of the engine 22, the total emissions Spn1, Spn2 of particulate matter are calculated assuming that the engine 22 is continuously operated at the temporary upper limit powers Pe1, Pe2, and the calculated total emissions Spn1, Spn2 are set as the remaining emissions Rpn1, Rpn2. Subsequently, the remaining emissions Rpn1 are calculated by subtracting the period emissions Qpn1 of particulate matter when assuming that the engine 22 is operated at the temporary upper limit power Pe1 from the previous remaining emissions (previous Rpn1), and the remaining emissions Rpn2 are calculated by subtracting the period emissions Qpn3 of particulate matter when the engine 22 is operated at the actual output Pe from the previous remaining emissions (previous Rpn2), and this process is repeatedly executed. Then, when the remaining emissions Rpn2 reach or exceed the remaining emissions Rpn1, as an upper limit release process, the control upper limit power Pelim is switched from the temporary upper limit power Pe2 or a value obtained by multiplying this by the coefficient kpe to the temporary upper limit power Pe1. Thereby, when the actual output Peac of the engine 22 is relatively low compared to the temporary upper limit power Pe2 (the period emissions Qpn3 are relatively small) and the remaining emissions Rpn2 decrease relatively gently, the remaining emissions Rpn2 are likely to reach or exceed the remaining emissions Rpn1 earlier, and the control upper limit power Pelim can be easily switched to the temporary upper limit power Pe1 earlier. As a result, it is possible to suppress continuously and wastefully limiting the output Pe of the engine 22.

[0051] In the hybrid vehicle 20 of the embodiment, it is assumed that the temporary upper limit power Pe1 is set based on the water temperature Twst1 at the first startup. However, it may be assumed that the rated output of the engine 22 or an output slightly lower than that is set as the temporary upper limit power Pe1.

[0052] In the hybrid vehicle 20 of the embodiment, when the upper limit release flag Fpe has a value of 0 and the remaining emission amount Rpn2 is greater than or equal to the remaining emission amount Rpn1, that is, when the value obtained by subtracting the remaining emission amount Rpn1 from the remaining emission amount Rpn2 is greater than or equal to 0, the upper limit release flag Fpe is switched to a value of 1. However, when the remaining emission amount Rpn2 is greater than or equal to the value obtained by adding the margin α to the remaining emission amount Rpn1, that is, when the value obtained by subtracting the remaining emission amount Rpn1 from the remaining emission amount Rpn2 is greater than or equal to the margin α, the upper limit release flag Fpe may be switched to a value of 1.

[0053] In the hybrid vehicle 20 of the embodiment, when the trip integrated air amount Iqa1 is greater than or equal to the threshold value Iqaref12 and the margin emission amount Apn of particulate matter is greater than or equal to the threshold value Apnref, the upper limit relaxation process is executed. However, when the margin emission amount Apn of particulate matter is greater than or equal to the threshold value Apnref, the upper limit relaxation process may be executed regardless of the trip integrated air amount Iqa1.

[0054] In the hybrid vehicle 20 of the embodiment, the threshold value Iqaref12 is set based on the water temperature Twst1 at the first start. However, the threshold value Iqaref12 may be set based on the water temperature Twst2 at the current start. Also, a constant value may be used as the threshold value Iqaref12.

[0055] In the hybrid vehicle 20 of the embodiment, a value obtained by multiplying the total emission amount Spn2 by the coefficient kpn is set as the threshold value Apnref. However, a constant value may be used as the threshold value Apnref.

[0056] In the hybrid vehicle 20 of the embodiment, as the upper limit relaxation process, the coefficient kpe is set such that the greater the margin emission amount Apn of particulate matter, the larger the value with respect to 1, and the value obtained by multiplying the temporary upper limit power Pe2 by the coefficient kpe is set as the control upper limit power Pelim. However, a constant value greater than 1 may be used as the coefficient kpe.

[0057] In the hybrid vehicle 20 of the embodiment, when starting the upper limit relaxation process, the control upper limit power Pelim is sharply increased to a value (Pe2·kpe) obtained by multiplying the temporary upper limit power Pe2 by the coefficient kpe, or when ending the upper limit relaxation process, the control upper limit power Pelim is sharply decreased from the value (Pe2·kpe) to the temporary upper limit power Pe2. However, in these cases, a slow change process such as a rate process or a smoothing process may be used to gradually change the control upper limit power Pelim. By doing so, sudden changes in the control upper limit power Pelim can be suppressed. Moreover, when the surplus emission amount Apn of particulate matter reaches the threshold value Apnref or more and the upper limit relaxation process is started, by gradually increasing the control upper limit power Pelim, it is possible to suppress the time until the surplus emission amount Apn reaches less than the threshold value Apnref and the upper limit relaxation process ends from becoming excessively short compared to the case where the control upper limit power Pelim is sharply increased.

[0058] In the hybrid vehicle 20 of the embodiment, the engine 22 is assumed to have the port injection valve 125 and the in-cylinder injection valve 126. However, the engine 22 may have only either the port injection valve 125 or the in-cylinder injection valve 126.

[0059] In the hybrid vehicle 20 of the embodiment, the variable valve timing device 150 of the engine 22 is configured to be able to continuously change the opening and closing timings of the intake valve 128 and the exhaust valve 133, respectively. However, the variable valve timing device 150 may be configured to be able to continuously change only either the intake valve 128 or the exhaust valve 133.

[0060] In the embodiment, the engine 22 and the motor MG1 are connected to the drive shaft 36 connected to the drive wheels 39a and 39b via the planetary gear 30, and the motor MG2 is connected to the drive shaft 36, and the hybrid vehicle 20 that travels while intermittently operating the engine 22 has been described. However, the present invention is not limited to this, and any vehicle capable of intermittently operating the engine 22 may be used. For example, as shown in the hybrid vehicle 220 of the modified example in FIG. 11, the motor MG is connected to the drive shaft 36 connected to the drive wheels 39a and 39b via the transmission 230, and the engine 22 is connected to the motor MG via the clutch 226, and the vehicle may be one that travels while intermittently operating the engine 22. Further, as shown in the engine vehicle 320 of the modified example in FIG. 12, the engine 22 is connected to the drive shaft 36 connected to the drive wheels 39a and 39b via the transmission 330, and the vehicle may be one capable of executing idling stop.

[0061] The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problems will be described. In the embodiment, the engine 22 corresponds to the "engine", and the engine ECU 24 corresponds to the "control device".

[0062] Note that the correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problems is an example for specifically explaining the form for implementing the invention described in the column of means for solving the problems in the embodiment, and thus does not limit the elements of the invention described in the column of means for solving the problems. That is, the interpretation of the invention described in the column of means for solving the problems should be made based on the description in that column, and the embodiment is merely a specific example of the invention described in the column of means for solving the problems.

[0063] As described above, the embodiments for implementing the present invention have been described using examples. However, the present invention is not limited to such examples, and it goes without saying that the present invention can be implemented in various forms without departing from the gist of the present invention.

Industrial Applicability

[0064] The present invention can be used in the vehicle manufacturing industry and the like.

Explanation of Signs

[0065] 20,220 Hybrid vehicle, 22 Engine, 23 Crankshaft, 24 Engine ECU, 30 Planetary gear, 36 Driveshaft, 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, 87 Vehicle speed sensor, 122 Air cleaner, 123 Intake pipe, 123a Airflow meter, 123t Temperature sensor, 124 Throttle valve, 124a Throttle valve position sensor, 125 Port injection valve, 126 In-cylinder injection valve, 128 Intake valve, 129 Combustion chamber, 130 Spark plug, 131 Cylinder bore, 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, 150 Variable valve timing device, 226 Clutch, 230, 330 Transmission, 320 Engine vehicle, MG1, MG2 Motors.

Claims

1. An engine, a control device that controls the engine so that the engine is operated within a range not exceeding the upper limit output for control, and a vehicle capable of intermittently operating the engine, wherein the control device, when starting the operation of the engine, calculates a first total emission amount of particulate matter when assuming that the engine is continuously operated at a first provisional upper limit output, and calculates a second total emission amount of the particulate matter when assuming that the engine is continuously operated at a second provisional upper limit output less than the first provisional upper limit output, sets the first total emission amount as a first remaining emission amount, and sets the second total emission amount as a second remaining emission amount, subtracts a first period emission amount of the particulate matter when assuming that the engine is operated at the first provisional upper limit output from a previous value of the first remaining emission amount to update the first remaining emission amount, and subtracts a second period emission amount of the particulate matter in the actual operation of the engine from a previous value of the second remaining emission amount to update the second remaining emission amount, and repeatedly executes an update process, when a difference obtained by subtracting the first remaining emission amount from the second remaining emission amount is less than a difference threshold, sets the second provisional upper limit output as the control upper limit output, and when the difference reaches the difference threshold or more, switches the control upper limit output to the first provisional upper limit output, a vehicle.

2. The vehicle according to Claim 1, wherein the control device sets the first provisional upper limit output as the control upper limit output regardless of the difference when a first integrated air amount in the current trip is equal to or more than a first threshold value, or when a second integrated air amount in the current operation of the engine is equal to or more than a second threshold value. a vehicle.

3. The vehicle according to Claim 1 or 2, wherein the control device sets the first provisional upper limit output based on a water temperature at the first start of the engine in the current trip, and sets the second provisional upper limit output based on a water temperature at the current start of the engine. a vehicle.

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