Hybrid vehicle

Abstract

To ensure the controllability of an engine.SOLUTION: A hybrid vehicle comprises an engine equipped in an exhaust system with a filter for removing particulate matter, a motor capable of inputting and outputting power to an output shaft of the engine, and a control device for controlling the engine and the motor such that when an accelerator is off, the engine is subjected to a fuel cut and motoring of the engine is performed by the motor. At a predetermined time when a filter temperature exceeds a determination temperature in the case where a duration time of the fuel cut during accelerator off is equal to or longer than a determination time, the control device controls the engine and the motor such that the engine is operated with a fuel injection amount smaller than a fuel injection amount at the time when the fuel cut is stopped and the engine is autonomously operated, and motoring of the engine is performed by the motor with motor torque that is set by using engine output torque based on a torque map for determining the engine output torque outputted from the engine at the predetermined time.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a hybrid vehicle, and more particularly to a hybrid vehicle including an engine equipped with a filter for removing particulate matter in an exhaust system and a motor.

Background Art

[0002] Conventionally, as this type of hybrid vehicle, a vehicle including an engine and a motor has been proposed (see, for example, Patent Document 1). The engine is equipped with a filter for removing particulate matter in an exhaust system. The motor inputs and outputs power to and from the output shaft of the engine. In this hybrid vehicle, the engine is fuel cut and the engine is motored by the motor to supply air containing oxygen to the filter. Thereby, particulate matter is burned to regenerate the filter.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above hybrid vehicle, when the engine is fuel cut to regenerate the filter, the filter may reach a high temperature. Therefore, when the filter becomes hot, the fuel cut is stopped and the fuel injection of the engine is restarted to suppress the temperature rise of the filter. At this time, if the fuel injection amount of the engine is large, the combustion amount of particulate matter in the filter increases, and the temperature of the filter rises. As a method for suppressing such a temperature rise of the filter, a method of operating the engine with a fuel injection amount less than the fuel injection amount when the engine is operating independently is conceivable. In this method, since a slight torque is output by combustion in the engine, if the engine is not motored with an appropriate motoring torque, the controllability of the engine may not be ensured, such as the engine surging.

[0005] The hybrid vehicle of the present invention has a main object of ensuring the controllability of the engine.

Means for Solving the Problems

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

[0007] The hybrid vehicle of the present invention is provided with an engine having a filter for removing particulate matter in the exhaust system, a motor capable of inputting and outputting power to and from the output shaft of the engine, and a control device for controlling the engine and the motor such that when the accelerator is off, the engine is fuel cut and the motor motors the engine, and is a hybrid vehicle comprising When the duration of the fuel cut during the accelerator-off state is equal to or longer than a determination time and the temperature of the filter exceeds a determination temperature at a predetermined time, the control device stops the fuel cut and operates the engine at a fuel injection amount less than the fuel injection amount during self-sustained operation, and controls the engine and the motor such that the motor motors the engine with a motoring torque based on the engine output torque set using a torque map that defines the engine output torque output from the engine at the predetermined time. This is the gist.

[0008] In this hybrid vehicle of the present invention, when the duration of the fuel cut during the accelerator-off state is equal to or longer than a determination time and the temperature of the filter exceeds a determination temperature at a predetermined time, fuel injection of the engine is performed at a fuel injection amount less than the fuel injection amount during self-sustained operation with the fuel cut stopped, and the engine and the motor are controlled such that the motor motors the engine with a motoring torque based on the engine output torque set using a torque map that defines the engine output torque output from the engine at the predetermined time. The engine and the motor are controlled such that the engine is motored with a motoring torque based on a torque map that defines the torque due to the rotational resistance of the engine at the predetermined time. Since fuel injection of the engine is performed at a fuel injection amount less than the fuel injection amount during self-sustained operation with the fuel cut stopped at the predetermined time, supply of air containing oxygen to the filter can be suppressed, and further temperature rise of the filter can be suppressed. At this time, since the motor motors the engine with a motoring torque based on the engine output torque set using a torque map that defines the engine output torque output from the engine at the predetermined time, the engine can be motored with an appropriate torque. As a result, controllability of the engine can be ensured. Note that the "determination time" is a threshold value for determining whether or not the filter may reach a high temperature due to continuous fuel cut. The "determination temperature" is a threshold value for determining whether or not the filter is at a high temperature.

[0009] In such a hybrid vehicle of the present invention, the torque map defines the relationship between the engine speed and the engine output torque when the engine is operated with a fuel injection amount less than the fuel injection amount when the engine operates independently, and the control device may set the motoring torque using the engine speed and the torque map. By doing so, the motoring torque can be set appropriately, so the engine can be motored with an appropriate motoring torque. Thereby, the controllability of the engine can be ensured.

[0010] Also, in the hybrid vehicle of the present invention, the determination time may be set to be shorter when the temperature of the filter is high than when it is low. When the temperature of the filter is high, the filter is more likely to become high temperature than when it is low. Therefore, by making the determination time shorter when the temperature of the filter is high than when it is low, when the temperature of the filter is high, compared to when it is low, the fuel cut is stopped earlier and the engine is operated with a fuel injection amount less than the fuel injection amount when the engine operates independently, and at a predetermined time, the engine is motored with the motoring torque based on the torque map that determines the engine output torque. Thus, it is possible to more appropriately suppress the filter temperature from reaching a high temperature.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Modes for Carrying Out the Invention

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

Example

[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. As shown in the figure, 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 as a power storage device, and a hybrid electronic control unit (hereinafter referred to as "HVECU") 70. As the engine device, the engine 22 and the HVECU 70 are applicable.

[0014] The engine 22 is configured as an internal combustion engine that outputs power using fuel such as gasoline or light oil, and is connected to the carrier 34 of the planetary gear 30 via a damper 28. FIG. 2 is a configuration diagram showing an outline of the configuration of the engine 22. As shown in the figure, the engine 22 sucks air cleaned by an air cleaner 122 into an intake pipe 123, passes it through a throttle valve 124, injects fuel from a fuel injection valve 126, mixes the air and fuel, and inhales this mixture into a combustion chamber 129 via an intake valve 128. Then, the inhaled mixture is explosively combusted by an electric spark from a spark plug 130, and the reciprocating motion of a piston 132 pushed down by the energy is converted into a rotational motion of a crankshaft (output shaft) 26. Exhaust discharged from the combustion chamber 129 to an exhaust pipe 133 via an exhaust valve 131 is discharged to the outside air via a purification device 134 and a PM filter 136. The purification device 134 has a purification catalyst (three-way catalyst) 134a that purifies harmful components such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx) in the exhaust. The PM filter 136 is formed as a porous filter made of ceramics, stainless steel, etc., and captures particulate matter (PM: Particulate Matter) such as soot in the exhaust.

[0015] The engine ECU 24 is configured as a microprocessor centered around a CPU, and in addition to the CPU, it includes a ROM that stores processing programs, a RAM that temporarily stores data, an input / output port, and a communication port. Signals from various sensors necessary for controlling the operation of the engine 22 are input into the engine ECU 24 via the input port. Examples of the signals input into the engine ECU 24 include the crank angle θcr from the crank position sensor 140 that detects the rotational position of the crankshaft 26 of the engine 22, and the coolant temperature Tw from the 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 the cam position sensor 144 that detects the rotational positions of the intake camshaft that opens and closes the intake valve 128 and the exhaust camshaft that opens and closes the exhaust valve 131. Further examples include the throttle opening TH from the throttle position sensor 124a that detects the position of the throttle valve 124, the intake air quantity Qa from the air flow meter 148 attached to the intake pipe 123, and the intake air temperature Ta from the temperature sensor 149 attached to the intake pipe 123. Also included are the air-fuel ratio AF from the air-fuel ratio sensor 135a attached to the exhaust pipe 133 and the oxygen signal O2 from the oxygen sensor 135b attached to the exhaust pipe 133.

[0016] Various control signals for controlling the operation of the engine 22 are output from the engine ECU 24 via the output port. Examples of the signals output from the engine ECU 24 include the control signal to the throttle motor 124b that adjusts the position of the throttle valve 124, the control signal to the fuel injection valve 126, and the control signal to the ignition plug 130. The engine ECU 24 is connected to the HV ECU 70 via the communication port.

[0017] The engine ECU 24 calculates the engine speed Ne based on the crank angle θcr from the crank position sensor 140, and calculates the temperature (catalyst temperature) Tc of the purification catalyst 134a of the purification device 134 based on the cooling water temperature Tw from the water temperature sensor 142 or the like. Further, the engine ECU 24 calculates the integrated value Ga of the intake air amount Qa from the air flow meter 148 since the start of the engine 22, and calculates the 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), etc., based on the intake air amount Qa and the engine speed Ne of the engine 22. Further, the engine ECU 24 also calculates the filter temperature Tf as the temperature of the PM filter 136 based on the engine speed Ne and the load factor KL of the engine 22, etc.

[0018] As shown in FIG. 1, the planetary gear 30 is configured as a single pinion type planetary gear mechanism, and includes a sun gear 31, a ring gear 32, a plurality of pinion gears 33 that mesh with the sun gear 31 and the ring gear 32 respectively, and a carrier 34 that supports the plurality of pinion gears 33 so as to be rotatable (revolvable) and revolvable. The rotor of the motor MG1 is connected to the sun gear 31 of the planetary gear 30. A drive shaft 36 connected to the drive wheels 39a and 39b via a differential gear 38 is connected to the ring gear 32 of the planetary gear 30. As described above, the crankshaft 26 of the engine 22 is connected to the carrier 34 of the planetary gear 30 via the damper 28. Therefore, the motor MG1, the engine 22, and the drive shaft 36 are connected to the sun gear 31, the carrier 34, and the ring gear 32 as three rotating elements of the planetary gear 30 so as to be arranged in this order in the collinear diagram of the planetary gear 30.

[0019] The motor MG1 is configured as a synchronous generator motor, for example. As described above, the rotor is connected to the sun gear 31 of the planetary gear 30. The motor MG2 is configured as a synchronous generator motor, for example, and the rotor is connected to the drive shaft 36. The inverters 41 and 42 are used to drive the motors MG1 and MG2 and are connected to the battery 50 via the power line 54. A smoothing capacitor 57 is attached to the power line 54. The motors MG1 and MG2 are rotationally driven by switching control of a plurality of switching elements (not shown) of the inverters 41 and 42 by a motor electronic control unit (hereinafter referred to as "motor ECU") 40.

[0020] The motor ECU 40 is configured as a microprocessor centered on a CPU, although not shown. In addition to the CPU, it includes a ROM that stores processing programs, a RAM that temporarily stores data, an input / output port, and a communication port. Signals from various sensors necessary for driving and controlling the motors MG1 and MG2 are input to the motor ECU 40 via the input port. For example, the rotational positions θm1 and θm2 from the rotational position detection sensors 43 and 44 that detect the rotational positions of the rotors of the motors MG1 and MG2, and the phase currents Iu1, Iv1, Iu2, and Iv2 from the current sensors 45u, 45v, 46u, and 46v that detect the currents flowing through each phase of the motors MG1 and MG2 are input. Switching control signals to the plurality of switching elements of the inverters 41 and 42 are output from the motor ECU 40 via the output port. The motor ECU 40 is connected to the HVECU 70 via the communication port. The motor ECU 40 calculates the electrical angles θe1 and θe2, the angular velocities ωm1 and ωm2, 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 detection sensors 43 and 44.

[0021] The battery 50 is configured as a lithium-ion secondary battery or a nickel-metal hydride secondary battery, for example, and is connected to the power line 54. This battery 50 is managed by a battery electronic control unit (hereinafter referred to as "battery ECU") 52.

[0022] Although not shown, the battery ECU 52 is configured as a microprocessor centered around a CPU. In addition to the CPU, it includes a ROM that stores processing programs, a RAM that temporarily stores data, an input / output port, and a communication port. Signals from various sensors necessary for managing the battery 50 are input into the battery ECU 52 via the input port. Examples of the signals input into the battery ECU 52 include the voltage Vb of the battery 50 from the voltage sensor 51a attached between the terminals of the battery 50, the current Ib of the battery 50 from the current sensor 51b attached to the output terminal of the battery 50, and the temperature Tb of the battery 50 from the temperature sensor 51c attached to the battery 50. The battery ECU 52 is connected to the HV ECU 70 via the communication port. The battery ECU 52 calculates the state of charge SOC based on the integrated value of the current Ib of the battery 50 from the current sensor 51b. 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.

[0023] Although not shown, the HV ECU 70 is configured as a microprocessor centered around a CPU It is provided with, in addition to the CPU, a ROM that stores a processing program, a RAM that temporarily stores data, an input / output port, and a communication port. Signals from various sensors are input to the HVECU 70 via the input port. Examples of the signals input to the HVECU 70 include an ignition signal from the ignition switch 80, a shift position SP from the shift position sensor 82 that detects the operation position of the shift lever 81. Also, an accelerator opening Acc from the accelerator pedal position sensor 84 that detects the depression amount of the accelerator pedal 83, a brake pedal position BP from the brake pedal position sensor 86 that detects the depression amount of the brake pedal 85, and a vehicle speed V from the vehicle speed sensor 88 can be mentioned. The atmospheric pressure Pout from the atmospheric pressure sensor 89 can also be mentioned. The HVECU 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via the communication port as described above.

[0024] The hybrid vehicle 20 of the embodiment configured in this way travels while switching between a hybrid driving mode (HV driving mode) in which it travels with the rotation of the engine 22 and an electric driving mode (EV driving mode) in which it travels with the rotation of the engine 22 stopped (while operating the engine 22 intermittently).

[0025] In the HV driving mode, basically, the HV ECU 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, the charging / discharging required power Pb* of the battery 50 (a positive value when discharging from the battery 50) is subtracted from the driving power Pd* to calculate the target power Pe* of the engine 22. The calculated target power Pe* is output from the engine 22, and the target rotational speed Ne* and target torque Te* of the engine 22, and the torque commands Tm1* and Tm2* of the motors MG1 and MG2 are set so that the driving torque Td* is output to the drive shaft 36. Then, the target rotational speed Ne* and target torque Te* of the engine 22 are transmitted to the engine ECU 24, and the torque commands Tm1* and Tm2* of the motors MG1 and MG2 are transmitted to the motor ECU 40. When receiving the target rotational speed Ne* and target torque Te* of the engine 22, the engine ECU 24 performs the operation control of the engine 22 so that the engine 22 is operated based on the target rotational speed Ne* and target torque Te*. As the operation control of the engine 22, intake air amount control for controlling the opening of the throttle valve 124, fuel injection control for controlling the fuel injection amount from the fuel injection valve 126, ignition control for controlling the ignition timing of the ignition plug 130, etc. are performed. When receiving the torque commands Tm1* and Tm2* of the motors MG1 and MG2, the motor ECU 40 performs the 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*.

[0026] In the EV driving mode, the HV ECU 70 sets the driving torque Td* based on the accelerator opening Acc and the vehicle speed V, 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 torque commands Tm1* and Tm2* of the motors MG1 and MG2 to the motor ECU 40. The control of the inverters 41 and 42 by the motor ECU 40 has been described above.

[0027] When the accelerator pedal 83 is turned off while the vehicle is running in the HV driving mode, the HVECU 70 sends a fuel cut command to the engine ECU 24 so that the fuel injection control in the engine 22 is stopped, and sets the engine output torque Te output to the crankshaft 26 of the engine 22 based on the engine speed Ne of the engine 22 using a first map. FIG. 3 is an explanatory diagram showing an example of the first map. The first map shows the relationship between the engine speed Ne of the engine 22 and the engine output torque Te. Now, since the engine 22 is in fuel cut (fuel injection control is stopped), the torque mainly due to the rotational resistance of the engine 22 becomes the engine output torque Te. Therefore, as shown in the figure, the engine output torque Te is set to be larger on the negative side when the engine speed Ne of the engine 22 is high compared to when it is low, when the torque output when the engine 22 is under load operation is set to a positive value. This is based on the fact that the rotational resistance of the engine 22 becomes larger when the engine speed Ne of the engine 22 is high compared to when it is low. Then, using the engine output torque Te and the gear ratio ρ of the planetary gear 30, the torque command Tm1* (= -Te·(ρ / ρ + 1)) of the motor MG1 is set so that the engine speed Ne of the engine 22 becomes the speed at the time when the fuel cut command was sent, and at the same time, the torque command Tm2* of the motor MG2 is set so that the driving torque Td* (braking torque) is output to the drive shaft 36 and sent to the motor ECU 40. The engine ECU 24 that has received the fuel cut command performs fuel cut and the like to stop the fuel injection control in the engine 22. The control of the inverters 41, 42 by the motor ECU 40 has been described above. By such control, the rotational resistance of the engine 22 is made to act on the drive shaft 36 as a braking force, and at the same time, the braking force by regeneratively controlling the motor MG2 is made to act on the drive shaft 36 to obtain a deceleration feeling imitating engine braking. Also, by supplying oxygen-containing air to the PM filter 136 during fuel cut, the particulate matter deposited on the PM filter 136 is burned to regenerate the PM filter 136. When the accelerator pedal 83 is turned on while the vehicle is running with fuel cut in this way, the HVECU 70 resumes the fuel injection control in the engine 22.Restart of fuel injection control is performed by transmitting a return command requesting restart of fuel injection control (return from fuel cut) to engine ECU 24, restarting fuel injection control in engine 22, and shifting to traveling in HV traveling mode.

[0028] Next, the operation of the hybrid vehicle 20 configured in this way will be described, particularly the operation when the PM filter 136 becomes hot during fuel cut with the accelerator pedal 83 off (accelerator off). FIG. 4 is a flowchart showing an example of a control routine executed by HVECU 70. This routine is repeatedly executed every predetermined time (for example, several msec) when the accelerator pedal 83 is off during traveling in HV traveling mode (when the accelerator is off).

[0029] When this routine is executed, HVECU 70 executes a process of inputting the filter temperature Tf, the engine speed Ne of engine 22, and the duration tm of fuel cut (step S100). The filter temperature Tf and the engine speed Ne are input via communication, which are calculated by engine ECU 24. The duration tm is the elapsed time since HVECU 70 transmitted a fuel cut command to engine ECU 24. The duration tm is reset to the value 0 when fuel injection control is restarted.

[0030] Subsequently, it is determined whether the duration tm is equal to or greater than the determination time tmref (step S110), and whether the filter temperature Tf exceeds the determination temperature Tfref (step S120). The determination time tmref is a threshold value for determining whether the PM filter 136 may reach a high temperature due to continuous fuel cut. The determination time tmref is set to be shorter when the filter temperature Tf is high than when it is low. The determination temperature Tfref is a threshold value for determining whether the PM filter 136 is at a high temperature, and is set to, for example, 500°C, 550°C, 600°C, etc.

[0031] When the continuous time tm is less than the determination time tmref in step S110, or when the continuous time tm is greater than or equal to the determination time tmref in step S110 and the filter temperature Tf is less than or equal to the determination temperature Tfref in step S120, fuel cut is executed when the accelerator pedal 83 is turned off during driving in the above-described HV driving mode (step S130), and this routine ends.

[0032] When the continuous time tm is greater than or equal to the determination time tmref in step S110 and the filter temperature Tf exceeds the determination temperature Tfref in step S120, a predetermined operation command for operating the engine 22 while performing fuel injection with a fuel injection amount less than the fuel injection amount during autonomous driving is transmitted to the engine ECU 24 (step S140). The engine ECU 24 that has received the predetermined operation command operates the engine 22 while performing fuel injection with a fuel injection amount less than the fuel injection amount during autonomous driving within a range where the engine 22 does not misfire. Thereby, supply of air containing oxygen to the PM filter 136 can be suppressed, and further temperature rise of the PM filter 136 can be suppressed.

[0033] Subsequently, the engine output torque Te is set (step S150) using the second map (torque map) showing the relationship between the engine speed Ne of the engine 22 at the time of a predetermined operation command and the engine output torque Te output to the crankshaft 26, and the engine speed Ne of the engine 22. FIG. 5 is an explanatory diagram showing an example of the second map. In the figure, the solid line shows the relationship between the engine speed Ne of the engine 22 and the engine output torque Te at the time of a predetermined operation command. For comparison, the broken line shows the relationship between the engine speed Ne of the engine 22 and the engine output torque Te in the first map illustrated in FIG. 3. The engine output torque Te in the second map becomes larger on the negative side when the engine speed Ne of the engine 22 is large compared to when it is small. This is based on the fact that the rotational resistance of the engine 22 becomes larger when the engine speed Ne of the engine 22 is large compared to when it is small. Also, the engine output torque Te in the second map is set to be smaller on the negative side compared to the engine output torque Te of the first map at the same engine speed Ne. This is because the engine 22 is being operated while performing fuel injection with a fuel injection amount less than the fuel injection amount during self-sustained operation within the range where the engine 22 does not misfire. Therefore, although it is very small, it is based on the fact that torque due to the combustion of the engine 22 is output.

[0034] When the engine output torque Te is set in this way, the torque command Tm1* (= -Te*(ρ / ρ + 1)) of the motor MG1 is set so that the rotational speed Ne of the engine 22 is maintained using the engine output torque Te and the gear ratio ρ of the planetary gear 30 (step S160). Then, the torque command Tm2* of the motor MG2 is set so that the driving torque Td* (braking torque) is output to the drive shaft 36 using the torque command Tm1* and the driving torque Td* (braking torque) (step S170). The torque commands Tm1* and Tm2* are transmitted to the motor ECU 40 (step S180), and this routine is terminated. The control of the inverters 41 and 42 by the motor ECU 40 has been described above. The engine output torque Te is set using the second map as the relationship between the rotational speed Ne of the engine 22 and the engine output torque Te at the time of a predetermined operation command. The torque command Tm1* is set using the set engine output torque Te. Since the motor MG1 (inverter 41) is controlled to be driven by the torque command Tm1*, the engine 22 can be motored with appropriate torque. Thereby, the controllability of the engine 22 can be ensured.

[0035] According to the hybrid vehicle 20 of the embodiment described above, when the continuous time tm of fuel cut when the accelerator pedal 83 is off is equal to or greater than the determination time tmref and the filter temperature Tf exceeds the determination temperature Tfref at a predetermined time, the fuel cut is stopped and the engine 22 is operated with a fuel injection amount less than the fuel injection amount during self-sustained operation. At the same time, the engine 22 and the motor MG1 are controlled so that the motor MG1 motors the engine 22 with the torque command Tm1* (motoring torque) set using the engine output torque Te based on the second map that determines the engine output torque Te output from the engine 22 at the time of a predetermined operation command. Therefore, the controllability of the engine 22 can be ensured.

[0036] Further, the second map defines the relationship between the engine speed Ne and the engine output torque Te when fuel injection is performed with a fuel injection amount less than the fuel injection amount when the engine 22 operates independently. Since the engine output torque Te is set using the engine speed Ne of the engine 22 and the second map, the controllability of the engine 22 can be further ensured.

[0037] In the hybrid vehicle 20 of the embodiment, the determination time tmref is set to be shorter when the filter temperature Tf is high than when it is low. However, the determination time tmref may be set to a constant value regardless of the filter temperature Tf.

[0038] 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", the motor MG1 corresponds to the "motor", and the engine ECU 24, the motor ECU 40, and the HC ECU 70 correspond to the "control device".

[0039] 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. Therefore, it 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.

[0040] As described above, the embodiments have been used to explain the forms for implementing the present invention. However, the present invention is not limited to such embodiments, 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

[0041] The present invention can be used in the manufacturing industry of hybrid vehicles and the like.

Description of Symbols

[0042] 20 Hybrid vehicle, 22 Engine, 24 Engine ECU, 26 Crankshaft, 28 Damper, 30 Planetary gear, 31 Sun gear 31, 32 Ring gear, 33 Pinion gear 33, 34 Carrier, 36 Drive shaft, 38 Differential gear, 39a, 39b Drive wheels, 40 Motor ECU, 41, 42 Inverter, 43, 44 Rotation position detection sensor, 45u, 45v, 46u, 46v Current sensor, 50 Battery, 51a Voltage sensor, 51b Current sensor, 51c Temperature sensor, 52 Battery ECU, 54 Power line, 57 Capacitor, 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 Atmospheric pressure sensor, 122 Air cleaner, 124 Throttle valve, 124a Throttle position sensor, 123 Intake pipe, 126 Fuel injection valve, 128 Intake valve, 129 Combustion chamber, 130 Spark plug, 131 Exhaust valve, 132 Piston, 133 Exhaust pipe, 134 Purification device, 134a Purification catalyst, 135a Air-fuel ratio sensor, 135b Oxygen sensor, 136 PM filter, 140 Crank position sensor, 142 Water temperature sensor, 144 Cam position sensor, 148 Airflow meter, 149 Temperature sensor, MG1, MG2 Motors.

Claims

1. An engine with a filter for removing particulate matter attached to an exhaust system, A motor capable of inputting and outputting power to and from an output shaft of the engine, A control device that controls the engine and the motor such that when the accelerator is off, the engine is fuel cut and the motor motors the engine, A hybrid vehicle comprising: When the duration of the fuel cut when the accelerator is off is equal to or longer than a determination time and the temperature of the filter exceeds a determination temperature at a predetermined time, the control device stops the fuel cut and operates the engine with a fuel injection amount less than the fuel injection amount for self-sustained operation, and the motor motors the engine with a motoring torque based on the engine output torque set using a torque map that defines the engine output torque output from the engine at the predetermined time. The engine and the motor are controlled as follows. Hybrid vehicle.

2. The hybrid vehicle according to claim 1, The torque map defines the relationship between the rotational speed of the engine and the engine output torque when the engine is operated with a fuel injection amount less than the fuel injection amount for self-sustained operation, The control device sets the motoring torque using the rotational speed of the engine and the torque map. Hybrid vehicle.

Images