JP2013112126A - Controller for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a controller for a vehicle, which is capable of improving fuel consumption and air exhaust emission at the same time.SOLUTION: The vehicle controller used for a hybrid vehicle, which is capable of intermittent traveling in which acceleration traveling and coasting traveling are repeated in a vehicle speed range R, has: a warm-up intermittent travel mode in which an engine is autonomously operated to perform warm-up and the intermittent traveling using drive power of a motor MG2 or drive power of the engine and the motor MG2 is performed; and a normal intermittent travel mode in which the intermittent traveling is performed using the drive power of the engine and the motor MG2, and includes HVECU that determines that the warm-up is completed on the condition that a cooling water temperature Tw reaches a target warm-up temperature To and switches the warm-up intermittent travel mode to the normal intermittent travel mode, and varies engine output Pe upon acceleration traveling based on the cooling water temperature Tw during execution of the warm-up intermittent travel mode.

Description

  The present invention relates to a vehicle control device applied to a vehicle including an internal combustion engine and an electric motor as driving force sources.

  Conventionally, as a vehicle to which this type of vehicle control device is applied, an internal combustion engine and a motor generator (hereinafter simply referred to as a motor) are provided as driving force sources, and the internal combustion engine is operated intermittently according to the running state of the vehicle. Hybrid vehicles that are controlled to be stopped are known.

  In recent years, some of such hybrid vehicles have, for example, accelerated traveling in which a driving force is generated by an internal combustion engine and the vehicle is driven by inertia by the inertial force of the vehicle without outputting mechanical power to the internal combustion engine. There is also a vehicle that travels according to a target vehicle speed that is set in advance by intermittent travel that alternately performs so-called coast down (hereinafter referred to as coasting). By carrying out such intermittent running, it is possible to realize a fuel-efficient driving with reduced fuel consumption compared to a case where the internal combustion engine is continuously driven and the vehicle is driven at a constant speed.

  By the way, in general, even in such a hybrid vehicle, since the internal combustion engine is driven by burning fuel, there is no change in discharging exhaust gas, and a catalyst is provided to purify the exhaust gas. It has been. In addition, such a catalyst needs to be sufficiently warmed to exert a purification action. Therefore, for example, when the internal combustion engine is started after being stopped for a long time, it is known that warm-up running for increasing the temperature of the catalyst is performed. During the warm-up running, the internal combustion engine is operated independently at a predetermined idle speed, and the vehicle is driven by driving the motor using the electric power stored in the storage battery.

  However, in a state where the remaining capacity of the storage battery has decreased to a predetermined value or less, even when the vehicle is warming up, it is an output that only generates power necessary for charging the storage battery, or an output that is necessary to drive the vehicle. The internal combustion engine must be operated. In such a case, exhaust emission may be deteriorated by exhausting an amount of exhaust gas that exceeds the purification capacity of the catalyst during warm-up.

  2. Description of the Related Art In recent years, as a hybrid vehicle aimed at improving exhaust emission during warm-up running, a vehicle control device that controls EV running in which the vehicle is run only by the driving force of a motor according to the remaining capacity of a storage battery. What was provided is known (for example, refer patent document 1).

  When the EV switch for selecting EV travel is turned ON, this conventional vehicle control device permits EV travel only when the remaining capacity of the storage battery is larger than the first threshold, and the storage battery during EV travel If the remaining capacity of the vehicle falls below a second threshold value that is smaller than the first threshold value, the continuation of EV traveling is prohibited. Therefore, according to this vehicle control device, the remaining capacity of the storage battery does not fall below the lower limit value at which power can be supplied during warm-up travel, and the drive of the motor during warm-up travel can be ensured. For this reason, the internal combustion engine is not operated at an output higher than maintaining the self-sustained operation during the warm-up running, and the exhaust gas exceeding the purification capacity of the catalyst is prevented from being discharged during the warm-up running. It is possible to improve exhaust emission.

JP 2005-51863 A

  However, in the conventional vehicle control device described in Patent Document 1, for example, the above-described intermittent traveling is not taken into consideration, and therefore the motor is switched to the intermittent traveling during the warm-up traveling. Also, of course, no consideration is given to how to control the operating state of the internal combustion engine. For this reason, in this conventional vehicle control device, there is a problem that it is impossible to achieve both improvement in fuel consumption due to intermittent running and improvement in exhaust emission during warm-up.

  The present invention has been made to solve the above-described conventional problems, and an object of the present invention is to provide a vehicle control device capable of achieving both improvement in fuel consumption and improvement in exhaust emission.

  In order to achieve the above object, a vehicle control apparatus according to the present invention includes (1) an internal combustion engine and an electric motor as a driving force source for generating a driving force of a vehicle, and a catalyst provided on an exhaust passage of the internal combustion engine. The vehicle travels by repeatedly performing an acceleration travel that travels by obtaining the driving force and an inertia traveling that travels by inertia without outputting the driving force from the driving force source within a vehicle speed range determined according to the vehicle speed. A vehicle control device used for a vehicle capable of intermittent travel, wherein the catalyst is warmed up by allowing the internal combustion engine to operate independently at a predetermined number of revolutions, and the driving force generated by the motor or the motor And a warm-up intermittent running mode in which the intermittent running is executed using the driving force generated by the internal combustion engine, and a normal intermittent running in which the intermittent running is executed using the driving force generated by the internal combustion engine and the electric motor. The warm-up operation is determined to be completed on the condition that a physical quantity that correlates with the progress state of the warm-up has reached a preset target value, Control means for switching to the intermittent travel mode is provided, and the control means is configured to vary the engine output of the internal combustion engine during acceleration travel based on the physical quantity during execution of the warm-up intermittent travel mode.

  With this configuration, the vehicle control device according to the present invention determines that the control unit has completed the warm-up on the condition that the physical quantity correlated with the progress state of the warm-up has reached a preset target value. The warm-up intermittent running mode is switched to the normal intermittent running mode. Further, during execution of the warm-up intermittent running mode, the engine output of the internal combustion engine at the time of accelerated running in the intermittent running is varied based on a physical quantity correlated with the warm-up progress state.

  For this reason, for example, when the vehicle is intermittently traveled in a low temperature region such as at the early stage of warm-up, the thermal efficiency is low and the operation efficiency of the internal combustion engine is reduced. Therefore, intermittent travel is performed by the output of the electric motor regardless of the engine output. Can do. Thereby, the fuel consumption at the initial stage of warm-up is improved. On the other hand, as the warm-up progresses, the physical quantity increases and the purification capacity of the catalyst also increases. Therefore, the engine output can be output within a range not exceeding the purification capacity. In this case, intermittent running can be performed using the outputs of the internal combustion engine and the electric motor while maintaining the purification ability of the catalyst.

  Therefore, the vehicle control device according to the present invention can suitably control the output of the electric motor and the internal combustion engine in accordance with the warming-up progress state, and can achieve both improvement in fuel consumption and improvement in exhaust emission. .

  Note that varying the engine output based on the physical quantity means, for example, varying the engine output based on a change in the physical quantity itself, or varying the engine output based on a change in the difference between the physical quantity and a preset target value. It is a concept that includes.

  Further, the vehicle control device according to the present invention is the vehicle control device according to (1), wherein (2) the control means sets an output upper limit value of the internal combustion engine that increases as the physical quantity increases, During the execution of the warm-up intermittent running mode, the engine output is varied within a range not exceeding the output upper limit value.

  With this configuration, in the vehicle control device according to the present invention, during the warm-up intermittent running mode, the engine output is variable within a range that does not exceed the output upper limit value of the internal combustion engine that increases as the physical quantity increases. For this reason, it is suppressed that the engine output which exceeds the purification capacity of the catalyst which increases with progress of warm-up is output.

  The vehicle control device according to the present invention is the vehicle control device according to (1), wherein (3) the control means is an internal combustion engine that increases as a difference between the physical quantity and the target value decreases. An output upper limit value is set, and the engine output is varied within a range not exceeding the output upper limit value during execution of the warm-up intermittent running mode.

  With this configuration, in the vehicle control device according to the present invention, the engine output is variable within a range that does not exceed the output upper limit value of the internal combustion engine that increases as the difference between the physical quantity and the target value decreases during the warm-up intermittent running mode. Is done. For this reason, it is suppressed that the engine output which exceeds the purification capacity of the catalyst which increases with progress of warm-up is output.

  The vehicle control device according to the present invention is the vehicle control device according to (2) or (3), wherein (4) the output upper limit value is set to a value capable of maintaining the purification capacity of the catalyst. Is done.

  With this configuration, the vehicle control device according to the present invention can prevent the engine output from exceeding the purification capacity of the catalyst.

  The vehicle control device according to the present invention is the vehicle control device according to any one of (1) to (4), wherein (5) the control means is the internal combustion engine during inertial running in the warm-up intermittent running mode. The engine is configured to operate independently.

  With this configuration, the control device for a vehicle according to the present invention can promote warming up of the catalyst because the control means causes the internal combustion engine to operate independently during inertial traveling in the warming-up intermittent traveling mode.

  The vehicle control device according to the present invention is the vehicle control device according to any one of (1) to (5), wherein (6) the control means includes a cooling water temperature of the internal combustion engine, a temperature of the catalyst, Any one of the oil temperatures of the internal combustion engine is used as the physical quantity.

  ADVANTAGE OF THE INVENTION According to this invention, the vehicle control apparatus which can aim at coexistence with the improvement of a fuel consumption and the improvement of exhaust emission can be provided.

1 is a schematic configuration diagram of a hybrid vehicle to which a vehicle control device according to a first embodiment of the present invention is applied. 1 is a schematic configuration diagram of an engine according to a first embodiment of the present invention. It is a flowchart of the intermittent traveling control performed by HVECU which concerns on the 1st Embodiment of this invention. It is a flowchart following the intermittent traveling control of FIG. It is a time chart of intermittent running control in a 1st embodiment of the present invention, (a) is a time chart of warm-up intermittent running mode, and (b) is a time chart of normal intermittent running mode. . It is a flowchart of the intermittent traveling control performed by HVECU which concerns on the 2nd Embodiment of this invention. It is a flowchart following the intermittent traveling control of FIG. It is a time chart of warm-up intermittent running mode in the 2nd embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
In the first embodiment of the present invention, an example will be described in which the vehicle control device is applied to a vehicle equipped with an internal combustion engine and an electric motor as a driving force source, that is, a so-called hybrid vehicle.

  As shown in FIG. 1, the hybrid vehicle 1 includes an engine 2 and motor generators (hereinafter simply referred to as motors) MG1 and MG2, which are electric motors capable of generating electric power, as driving force sources that generate the driving force of the hybrid vehicle 1. Prepare. The hybrid vehicle 1 includes a drive device 3 and a vehicle control device 4.

  The drive device 3 includes motors MG1 and MG2, a power split and integration mechanism 40, a speed reduction mechanism 70, and a differential mechanism 80, and constitutes a so-called hybrid transaxle. The drive device 3 is combined with the engine 2 to constitute a power output device (power plant).

  The engine 2 is configured as an internal combustion engine capable of outputting power using a hydrocarbon fuel such as gasoline or light oil.

  As shown in FIG. 2, the engine 2 sucks the air purified by the air cleaner 20 through the throttle valve 21 and the intake passage 22. Thereafter, the engine 2 injects gasoline from the fuel injection valve 23 and mixes the sucked air and gasoline, and sucks this mixture into the fuel chamber via the intake valve 24. Next, the engine 2 explodes and burns the sucked air-fuel mixture with electric sparks from the spark plug 25, and converts the reciprocating motion of the piston 26 pushed down by the energy into the rotational motion of the engine output shaft 12.

  On the exhaust passage 28 of the engine 2, a purification including an exhaust gas purification catalyst (hereinafter referred to as a three-way catalyst) 29 a that purifies harmful components such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx). A device 29 is provided. Therefore, the exhaust from the engine 2 is discharged to the outside air through the purification device 29. The three-way catalyst 29a in the present embodiment constitutes a catalyst according to the present invention.

The three-way catalyst 29a oxidizes unburned components (HC, CO) in the exhaust gas and simultaneously reduces NOx when the air-fuel ratio (A / F) of the exhaust gas introduced into the catalyst is substantially the stoichiometric air-fuel ratio. The exhaust gas is purified by the function. In the engine 2, in order to make the three-way catalyst 29a function most effectively, the air-fuel ratio (actual air-fuel ratio) matches the stoichiometric air-fuel ratio based on output values of an A / F sensor 207 and an O ₂ sensor 208 described later. Thus, the air-fuel ratio feedback control is executed by the engine ECU 200.

  In addition, the three-way catalyst 29a needs to be sufficiently warmed in order to exhibit the purification ability for purifying the harmful components as described above. Therefore, when the engine 2 is started after being stopped for a long time, the temperature of the three-way catalyst 29a (catalyst bed temperature) is low. Therefore, it is necessary to warm up the temperature, that is, to activate the three-way catalyst 29a. Such warm-up of the three-way catalyst 29a is performed by executing catalyst warm-up control described later.

  The engine 2 also includes a variable valve timing mechanism 90 that can continuously change the opening / closing timing VT of the intake valve 24. The variable valve timing mechanism 90 includes a vane type VVT controller (not shown) and an oil control valve, and continuously changes the angle of an intake camshaft (not shown) at the opening / closing timing VT of the intake valve 24.

  As shown in FIG. 1, a power split and integration mechanism 40 is coupled to the engine output shaft 12. The engine 2 outputs mechanical power (hereinafter referred to as engine output) from the engine output shaft 12 toward the drive wheels 6. This mechanical power can be controlled by the engine ECU 200.

  The motors MG1 and MG2 are so-called motor generators having both a function as an electric motor that converts supplied electric power into mechanical power and a function as a generator that converts input mechanical power into electric power. The motor MG1 is mainly used as a generator, and the motor MG2 is mainly used as an electric motor. Motor MG2 in the present embodiment constitutes an electric motor according to the present invention.

  The motors MG1 and MG2 are composed of permanent magnet AC synchronous motors or the like. The motors MG1 and MG2 have stators 53 and 54 and rotors 51 and 52, respectively. The stators 53 and 54 are supplied with AC power from inverters 61 and 62 (described later) to form a rotating magnetic field. The rotors 51 and 52 are coupled to the power split and integration mechanism 40 and are rotated by being attracted to a rotating magnetic field. The motors MG1 and MG2 are provided with resolvers (not shown) that detect the rotation angle positions of the rotors 51 and 52, respectively. The resolver transmits a signal corresponding to the detected rotational angle position of the rotors 51 and 52 to the motor ECU 60.

  The motors MG1 and MG2 can operate as electric motors upon receiving power supplied from the secondary battery (storage battery) 105 (hereinafter, this operation state is referred to as power running). On the other hand, when a motor shaft (not shown) is rotated by an external force, it can operate as a generator that generates an electromotive force to charge the secondary battery 105 (hereinafter, this operation state is referred to as regeneration).

  In addition, the drive device 3 is provided with inverters 61 and 62 and a motor ECU 60. The inverters 61 and 62 are connected to the stators 53 and 54, respectively. The inverters 61 and 62 are configured to convert the DC power supplied from the secondary battery 105 into AC power and supply the AC power to the corresponding motors MG1 and MG2, respectively. Further, the inverters 61 and 62 are configured such that AC power from the motors MG1 and MG2 is converted into DC power and can be collected in the secondary battery 105. Power supply and power recovery of inverters 61 and 62 are controlled by motor ECU 60.

  The power split and integration mechanism 40 is a power transmission mechanism that transmits mechanical power output from the engine 2 and the motors MG1 and MG2 to the drive shaft 7. The power split and integration mechanism 40 includes a single pinion type power split planetary gear 40a and a reduction planetary gear 40c.

  Power split planetary gear 40a is configured to be able to split mechanical power output from engine 2 into mechanical power for driving motor MG1 and mechanical power for driving reduction mechanism 70. The power split planetary gear 40a includes a sun gear 42, a planetary pinion 43, a planetary carrier 44, and a ring gear 45a.

  Sun gear 42 is coupled to rotor 51 of motor MG1. The planetary pinion 43 is supported so as to be able to revolve and rotate with respect to the planetary carrier 44. The planetary carrier 44 is coupled to the engine output shaft 12. The power split planetary gear 40a configured as described above splits the engine output of the engine 2 into mechanical power transmitted to the sun gear 42 via the planetary pinion 43 and mechanical power transmitted to the ring gear 45a. ing. The mechanical power transmitted from the engine 2 to the sun gear 42 is transmitted to the rotor 51 of the motor MG1 and used for power generation.

  The reduction planetary gear 40c is configured to be able to transmit the mechanical power output from the motor MG2 to the reduction mechanism 70 by reducing the rotational speed and increasing the torque. The reduction planetary gear 40c includes a sun gear 46, a planetary carrier 47, a planetary pinion 48, and a ring gear 45c.

  Sun gear 46 is coupled to rotor 52 of motor MG2. The planetary carrier 47 is fixed to the housing of the driving device 3. The planetary pinion 48 is supported so as to be capable of rotating with respect to the planetary carrier 47. The reduction planetary gear 40c configured in this way is configured to transmit the mechanical power output from the motor MG2 to the ring gear 45c via the planetary pinion 48 by reducing the rotational speed and increasing the torque.

  The power split planetary gear 40a and the reduction planetary gear 40c are arranged concentrically, and the ring gear 45a and the ring gear 45c are integrally coupled. A counter drive gear 49 that meshes with the counter driven gear 74 of the speed reduction mechanism 70 is provided on the outer peripheral side of the ring gears 45a and 45c. The power split and integration mechanism 40 integrates the mechanical power transmitted from the motor MG2 to the ring gear 45c and the mechanical power transmitted from the engine 2 to the ring gear 45a and transmits them from the counter drive gear 49 to the speed reduction mechanism 70.

  The speed reduction mechanism 70 includes a counter driven gear 74 and a final drive gear 78. The counter driven gear 74 meshes with the counter drive gear 49, and the final drive gear 78 meshes with the ring gear 82 of the differential mechanism 80. The counter driven gear 74 and the final drive gear 78 are arranged concentrically and are integrally coupled. The speed reduction mechanism 70 transmits the mechanical power transmitted from the power split and integration mechanism 40 to the counter driven gear 74 from the final drive gear 78 to the differential mechanism 80 by reducing the rotational speed and increasing the torque.

  The differential mechanism 80 includes a ring gear 82 that meshes with the final drive gear 78. The differential mechanism 80 distributes and outputs the mechanical power transmitted from the speed reduction mechanism 70 to the ring gear 82 to the left and right drive wheels 6.

  As shown in FIGS. 1 and 2, the vehicle control device 4 includes a hybrid electronic control device (hereinafter simply referred to as HVECU) 100, an engine ECU 200, a motor ECU 60, an accelerator pedal position sensor 101, a vehicle speed sensor 102, and Various sensors including the water temperature sensor 202 and the eco switch 104 are included.

  The HVECU 100 includes, for example, a microcomputer including a CPU, a RAM, a ROM, an input / output interface, and the like. The CPU uses a temporary storage function of the RAM and performs signal processing according to a program stored in advance in the ROM. It is like that. Various control constants and various maps are stored in advance in the ROM.

  HVECU 100 controls engine 2 and motors MG1, MG2 in a coordinated manner. Further, the HVECU 100 is configured to be able to execute intermittent traveling control, which will be described later, in cooperation with the engine ECU 200 and the motor ECU 60 in accordance with detection results of the accelerator pedal position sensor 101 and the vehicle speed sensor 102. HVECU 100 in the present embodiment constitutes a control means according to the present invention.

  Further, the HVECU 100 can switch between an operating state and a non-operating state of the engine 2 by starting or stopping the operation of the engine 2 while the vehicle is traveling. The non-operating state means a state where the engine output is zero and the engine rotational speed is zero, that is, the engine output shaft 12 is stationary and no engine brake torque is generated in the engine 2. On the other hand, the operating state means a state in which the engine 2 outputs mechanical power (engine output) from the engine output shaft 12.

  For example, when the engine 2 is deactivated during traveling at a constant vehicle speed, the HVECU 100 increases the motor output while maintaining the motor rotation speed of the motor MG2, and the engine output of the engine 2 is reduced to zero. Then, the rotor 51 of the motor MG1 is idled in the direction opposite to that of the ring gears 45a and 45c, so that the engine rotational speed becomes zero. In this way, the operation of the engine 2 can be stopped and put into a non-operating state.

  When the engine 2 is in an operating state while the vehicle is traveling at a constant vehicle speed, the HVECU 100 reduces the motor output while keeping the motor rotation speed of the motor MG2 unchanged, and causes the rotor 51 of the motor MG1 to move to the ring gears 45a and 45c. The engine 2 is cranked by increasing the engine rotational speed by powering in the same rotational direction. As a result, the engine 2 can be started and put into an operating state.

  The engine ECU 200 includes, for example, a microcomputer including a CPU, a RAM, a ROM, an input / output interface, and the like. The CPU uses a temporary storage function of the RAM and performs signal processing according to a program stored in advance in the ROM. To do. Various control constants and various maps are stored in advance in the ROM.

A crank position sensor 201, a water temperature sensor 202, a cam position sensor 203, a throttle valve position sensor 204, an air flow meter 205, a temperature sensor 206, an A / F sensor 207, and an O ₂ sensor 208 are connected to the engine ECU 200.

The crank position sensor 201 detects the rotational position of the engine output shaft 12, that is, the crank angle θcr and the engine speed Ne. The water temperature sensor 202 detects the temperature of the cooling water of the engine 2, that is, the cooling water temperature Tw. The cam position sensor 203 detects the rotational position of the exhaust camshaft that opens and closes the intake camshaft and the exhaust valve, that is, the cam angle θca. The throttle valve position sensor 204 detects the throttle opening TH of the throttle valve 21. The air flow meter 205 is attached to the intake pipe and detects the mass flow rate of the intake air, that is, the intake air amount Qa. The temperature sensor 206 is attached to the intake pipe and detects the intake air temperature Ta. The A / F sensor 207 has a linear characteristic with respect to the air-fuel ratio, and continuously detects the air-fuel ratio over a relatively wide range. The O ₂ sensor 208 has a characteristic (Z characteristic) in which the output value changes abruptly at the stoichiometric air-fuel ratio, changes the oxygen concentration in the exhaust gas into an electromotive force, and the air-fuel ratio is leaner or richer than the stoichiometric air-fuel ratio. To detect. Each of these sensors outputs a signal corresponding to the detection result to engine ECU 200.

  The engine ECU 200 performs various control signals for driving the engine 2, such as a drive signal to the fuel injection valve 23, a drive signal to the throttle motor 21a that adjusts the throttle opening TH, a control signal to the ignition coil 210, A control signal to the variable valve timing mechanism 90 is output.

  The engine ECU 200 is in communication with the HVECU 100, controls the operation of the engine 2 by a control signal from the HVECU 100, and outputs data related to the operating state of the engine 2 as necessary.

  Motor ECU 60 receives signals relating to the required torque and the required rotational speed from HVECU 100 and controls inverters 61 and 62. The motor ECU 60 controls the inverters 61 and 62 so that the rotational speeds of the rotors 51 and 52 (hereinafter referred to as motor rotational speeds) and the mechanical power output from the rotors 51 and 52 (for the motors MG1 and MG2). Hereinafter, the motor output) can be adjusted.

  The accelerator pedal position sensor 101 detects the amount of operation of the accelerator pedal 5 by the driver. The accelerator pedal position sensor 101 is connected to the HVECU 100 and transmits a signal corresponding to the detected operation amount of the accelerator pedal 5 (hereinafter referred to as accelerator operation amount Acc) to the HVECU 100.

  The vehicle speed sensor 102 detects the vehicle speed V of the hybrid vehicle 1. The vehicle speed sensor 102 is connected to the HVECU 100 and transmits a signal corresponding to the detected vehicle speed V to the HVECU 100.

  The eco switch 104 is a switch for instructing the HVECU 100 to perform fuel consumption travel so that the driver can select vehicle travel prior to the suppression of fuel consumption by the engine 2 (hereinafter referred to as fuel efficiency travel). The eco switch 104 is provided at a place where it can be operated by the driver, such as an instrument panel in the vehicle interior. The eco switch 104 is configured to be switchable between an ON state and an OFF state by a driver's operation. Further, the HVECU 100 detects the ON state and the OFF state of the eco switch 104.

  Further, the hybrid vehicle 1 is provided with a secondary battery 105, a boost converter 106, and a battery ECU 107. The secondary battery 105 is electrically connected to the inverters 61 and 62 via the boost converter 106.

  The secondary battery 105 stores electric power supplied to the motors MG1 and MG2, and is configured to be able to charge and discharge between the motors MG1 and MG2. Boost converter 106 boosts the voltage of secondary battery 105 and converts it to the supply voltage of inverters 61 and 62. The battery ECU 107 monitors the temperature, voltage, charge / discharge current value, etc. of the secondary battery 105.

  Further, the battery ECU 107 calculates the state of charge (SOC) and charge / discharge power of the secondary battery 105 from information such as the temperature, voltage, and charge / discharge current value of the secondary battery 105. The battery ECU 107 is connected to the HVECU 100, and exchanges signals with the HVECU 100, such as transmitting a signal corresponding to the storage state of the secondary battery 105 and charge / discharge power to the HVECU 100, for example.

  In the hybrid vehicle 1 configured as described above, the user required power P is calculated based on the accelerator operation amount Acc and the vehicle speed V, and the required power corresponding to the user required power P is output to the counter drive gear 49. The engine 2 and the motors MG1, MG2 are controlled for operation. In addition, as the travel mode of the hybrid vehicle 1, for example, there are a hybrid travel mode, a motor travel mode, a regenerative travel mode, and the like.

  In the hybrid travel mode, the hybrid vehicle 1 is caused to travel using both the engine 2 and the motor MG2 as driving power sources while the motor MG1 generates power using the engine output of the engine 2. In the motor travel mode, the hybrid vehicle 1 is traveled using the motor MG2 as a driving force source while the engine 2 is stopped. The regenerative travel mode is a travel mode in which power is generated by the motor MG2 using energy input via the speed reduction mechanism 70 when a predetermined condition such as a deceleration request is established.

  Further, in the hybrid vehicle 1 according to the present embodiment, intermittent driving control is executed by the HVECU 100 when a predetermined condition is satisfied during traveling. This intermittent travel control can be executed in a vehicle speed range where the vehicle speed V is greater than zero (V> 0). That is, while the hybrid vehicle 1 is traveling, intermittent traveling control can be executed in all vehicle speed ranges on condition that a predetermined condition is satisfied. When the intermittent travel control is executed, the hybrid vehicle 1 performs acceleration travel that travels by obtaining the driving force generated by the engine 2 and / or the motor MG2, and inertia without outputting the driving force from the engine 2 and the motor MG2. It is possible to perform intermittent traveling that travels by repeatedly performing inertial traveling that travels in the vehicle speed range R that is determined according to the vehicle speed V.

  Specifically, the HVECU 100, when the predetermined condition is satisfied while the hybrid vehicle 1 is traveling, the control vehicle speed VS, the upper limit vehicle speed VH that is the upper limit value of the vehicle speed range R, and the lower limit vehicle speed VL that is the lower limit value of the vehicle speed range R. Is set. Here, the predetermined condition is that the eco switch 104 is turned ON and the user request power P is substantially constant. The user required power P is calculated by the HVECU 100 by referring to a map that is obtained by experimentally determining in advance the relationship between the vehicle speed V and the user required power P using the accelerator operation amount Acc as a parameter. An example in which the user request power P is substantially constant includes, for example, a case where the accelerator operation amount Acc by the driver is constant during traveling at a constant vehicle speed V. The case where the accelerator operation amount Acc is constant includes the case where the accelerator operation amount Acc is zero. Here, the user request power P being substantially constant means that the user request power is maintained within a predetermined range (for example, ± 3 km / h) within a predetermined time, although there is some variation. Means state.

  Further, the HVECU 100 sets the vehicle speed V at the time when the user required power P becomes substantially constant during the travel after the eco switch is turned on as the control vehicle speed VS, and increases the vehicle speed by a vehicle speed that is set in advance based on the control vehicle speed VS. An upper limit vehicle speed VH and a lower limit vehicle speed VL are set on the side and the low vehicle speed side, respectively. The vehicle speed range R is determined by the set upper limit vehicle speed VH and lower limit vehicle speed VL. More specifically, it is determined whether the vehicle speed range R is expanded or reduced depending on how much the upper limit vehicle speed VH and the lower limit vehicle speed VL are set to the high vehicle speed side and the low vehicle speed side from the control vehicle speed VS. Here, the vehicle speed range R may be expanded as the vehicle speed V increases, for example. Thus, the vehicle speed range R is determined according to the vehicle speed V.

  Further, the HVECU 100 sets the upper limit vehicle speed VH and the lower limit vehicle speed VL so that the vehicle speed width between the upper limit vehicle speed VH and the control vehicle speed VS and the vehicle speed width between the control vehicle speed VS and the lower limit vehicle speed VL are the same. That is, the control vehicle speed VS is set between the upper limit vehicle speed VH and the lower limit vehicle speed VL.

  Further, the HVECU 100 starts the engine 2 when the coolant temperature Tw is equal to or lower than a predetermined warm-up execution temperature, for example, and causes the engine 2 to operate independently at a predetermined rotation speed (for example, about 1500 rpm to 1800 rpm). Catalyst warm-up control is executed. As a result, it is possible to increase the temperature of the exhaust gas and promote the activation of the three-way catalyst 29a. Instead of comparing the cooling water temperature Tw and the warm-up execution temperature, the three-way catalyst estimated by the engine ECU 200 or the like based on the intake air amount Qa, the cooling water temperature Tw, the air-fuel ratio AF, the ignition timing retardation amount, etc. It may be determined whether the catalyst warm-up control should be executed by comparing the temperature 29a (catalyst bed temperature) with a predetermined reference temperature. The temperature of the three-way catalyst 29a (catalyst bed temperature) may be directly detected by, for example, providing a catalyst temperature sensor near the three-way catalyst 29a. Further, in the catalyst warm-up control, warm-up may be completed early by performing control such as retarding the ignition timing from the normal time or increasing the fuel injection amount from the normal time.

  In addition, during the catalyst warm-up control, the HVECU 100 has reached that the coolant temperature Tw, which is a physical quantity correlated with the warm-up progress state of the three-way catalyst 29a, has reached the target warm-up temperature To as a predetermined target value. It is determined that the warm-up of the three-way catalyst 29a has been completed. Here, in addition to the cooling water temperature Tw, for example, the temperature of the three-way catalyst 29a (catalyst bed temperature), the oil temperature of the engine 2, or the like can be used as the physical quantity. In this case, as described above, the temperature of the three-way catalyst 29a (catalyst bed temperature) can be detected by estimation by the engine ECU 200 or the like or by providing a catalyst temperature sensor, and the oil temperature of the engine 2 is provided by an oil temperature sensor. Can be detected.

  Further, when intermittent travel control is executed during catalyst warm-up control, the HVECU 100 switches between the warm-up intermittent travel mode and the normal intermittent travel mode according to the warm-up progress state of the three-way catalyst 29a. It is like that. Specifically, the HVECU 100 determines that the warm-up of the three-way catalyst 29a has been completed on the condition that the coolant temperature Tw has reached the target warm-up temperature To, and changes from the warm-up intermittent travel mode to the normal intermittent travel mode. Switch.

  Here, in the warm-up intermittent running mode, the engine 2 is independently operated at a predetermined rotation number to warm up the three-way catalyst 29a, and intermittent running is executed using the driving force generated by the motor MG2. Mode. The normal intermittent traveling mode is a mode in which intermittent traveling is performed using the driving force generated by the engine 2 and the motor MG2.

  Next, with reference to FIG. 3 to FIG. 5A and FIG. 5B, the intermittent travel control during the catalyst warm-up control according to the present embodiment will be described.

  The process flow of the intermittent traveling control shown in FIGS. 3 and 4 is executed at predetermined time intervals while the hybrid vehicle 1 is traveling. In particular, this processing flow is executed during execution of catalyst warm-up control.

  As shown in FIG. 3, first, the HVECU 100 determines whether or not the vehicle speed V is greater than zero (V> 0) (step S1). When it is determined that V> 0 is not satisfied, the HVECU 100 ends the present process without executing the intermittent travel control.

  When it is determined that V> 0, the HVECU 100 determines whether or not the eco switch 104 is in the ON state (step S2). When it is determined that the eco switch 104 is not in the ON state, that is, the eco switch 104 is in the OFF state, the HVECU 100 determines that the fuel consumption travel is not selected by the driver and performs the intermittent travel control. This process ends.

  When it is determined that the eco switch 104 is in the ON state, the HVECU 100 determines whether the user request power P is substantially constant (step S3). If the user request power P is not substantially constant, the HVECU 100 interrupts the intermittent travel if the intermittent travel is executed in the previous cycle (step S17), and proceeds to step S18. In step S18, the HVECU 100 determines whether the hybrid vehicle 1 is accelerating. Whether or not the vehicle is accelerating is determined based on, for example, the amount of change in the vehicle speed V detected by the vehicle speed sensor 102.

  When it is determined that the hybrid vehicle 1 is accelerating, the HVECU 100 drives the engine 2 and the motor MG2 in a coordinated manner so that a desired driving force is generated based on the user requested power P (step S19). Note that, during the motor travel mode or when the three-way catalyst 29a has not been warmed up, only the motor MG2 is driven to generate a desired driving force based on the user request power P.

  On the other hand, if it is determined that the hybrid vehicle 1 is not accelerating, the HVECU 100 determines that the hybrid vehicle 1 is in a decelerating state and stops the engine 2 and stops the driving of the motor MG2, or the driving wheels 6 The motor MG2 is rotated by the power transmitted from the motor to operate as a generator (regenerative operation) (step S20).

  When it is determined in step S3 that the user required power P is substantially constant, the HVECU 100 determines whether or not the coolant temperature Tw is equal to or higher than the target warm-up temperature To (step S4). When the HVECU 100 determines that the coolant temperature Tw is not equal to or higher than the target warm-up temperature To, the warm-up intermittent running mode is executed (step S5).

Specifically, as shown in FIG. 5A, the HVECU 100 causes the engine 2 to operate independently, and repeatedly executes acceleration traveling and inertial traveling in a vehicle speed range R determined by the upper limit vehicle speed VH and the lower limit vehicle speed VL. Controls driving of the motor MG2. In this warm-up intermittent running mode, the motor output Pm of the motor MG2 is set as the motor output Pm ₁ during acceleration running. On the other hand, during coasting, the motor output Pm of the motor MG2 is set to zero.

  Further, the engine output Pe of the engine 2 is an engine output Pe_idle that does not output mechanical power toward the drive wheels 6 based on the self-sustained operation. Thus, the acceleration travel and the inertia travel are repeated between the upper limit vehicle speed VH and the lower limit vehicle speed VL by driving the motor MG2 until the warm-up of the three-way catalyst 29a is completed. The engine output Pe in the present embodiment corresponds to the engine output in the present invention.

  Here, in the present embodiment, the engine output Pe during the warm-up intermittent running mode is the engine output Pe_idle. However, the engine output Pe_idle may be a relatively low load engine output that does not exceed the purification capacity of the three-way catalyst 29a. Good.

  If the HVECU 100 determines in step S4 that the coolant temperature Tw is equal to or higher than the target warm-up temperature To, the HVECU 100 shifts to the normal intermittent running mode in step S11 shown in FIG. The normal intermittent travel mode will be described later.

  Next, the HVECU 100 determines in step S6 whether or not the vehicle speed V has increased to the upper limit vehicle speed VH. If the HVECU 100 determines that the vehicle speed V has increased to the upper limit vehicle speed VH, the HVECU 100 continues the self-sustained operation of the engine 2 and stops driving the motor MG2 (step S7) and ends this process. That is, the HVECU 100 shifts the hybrid vehicle 1 from the acceleration traveling to the inertia traveling on the condition that the vehicle speed V has reached the upper limit vehicle speed VH.

On the other hand, if it is determined in step S6 that the vehicle speed V has not increased to the upper limit vehicle speed VH, the HVECU 100 determines whether the vehicle speed V has decreased to the lower limit vehicle speed VL (step S8). HVECU100, when the vehicle speed V is determined to have dropped to the lower limit vehicle speed VL is configured to continue the autonomous operation of the engine 2, drive the motor MG2 by the motor output Pm ₁ (step S9) and ends the present process. That is, the HVECU 100 shifts the hybrid vehicle 1 from coasting to acceleration traveling on the condition that the vehicle speed V has reached the lower limit vehicle speed VL.

On the other hand, if it is determined in step S8 that the vehicle speed V has not decreased to the lower limit vehicle speed VL, the HVECU 100 continues the independent operation of the engine 2 and maintains the driving state (motor state) of the motor MG2. (Step S10) This process ends. That is, if the hybrid vehicle 1 is being accelerated running, maintaining the driving of the motor MG2 at the motor output Pm _1, the hybrid vehicle 1 to keep the drive stop of the motor MG2 if during coasting on the contrary . However, the engine 2 continues to operate independently during acceleration running and inertia running.

  Next, the normal intermittent traveling mode will be described with reference to FIG.

  As shown in FIG. 4, when the HVECU 100 determines that the coolant temperature Tw is equal to or higher than the target warm-up temperature To (YES in step S4 in FIG. 3), the normal intermittent running mode is executed (step S11). . That is, the HVECU 100 switches from the warm-up intermittent running mode to the normal intermittent running mode on condition that the coolant temperature Tw has reached the target warm-up temperature To.

Specifically, as shown in FIG. 5B, the HVECU 100 cooperates the engine 2 and the motor MG2 to repeatedly execute acceleration traveling and inertial traveling in a vehicle speed range R determined by the upper limit vehicle speed VH and the lower limit vehicle speed VL. Control. In this normal intermittent traveling mode, during acceleration traveling, the motor output Pm of the motor MG2 is set to a motor output Pm ₂ smaller than the motor output Pm ₁ , and the engine output Pe of the engine ₂ is set to an engine output Pe ₂ larger than the engine output Pe_idle. . These motor output Pm ₂ and engine output Pe ₂ are distributed at a predetermined distribution ratio according to the user request power P.

  Next, the HVECU 100 determines in step S12 whether or not the vehicle speed V has increased to the upper limit vehicle speed VH. If the HVECU 100 determines that the vehicle speed V has increased to the upper limit vehicle speed VH, the HVECU 100 stops driving the engine 2 and the motor MG2 (step S13) and ends the present process. That is, the HVECU 100 shifts the hybrid vehicle 1 from the acceleration traveling to the inertia traveling on the condition that the vehicle speed V has reached the upper limit vehicle speed VH.

On the other hand, if it is determined in step S12 that the vehicle speed V has not increased to the upper limit vehicle speed VH, the HVECU 100 determines whether the vehicle speed V has decreased to the lower limit vehicle speed VL (step S14). If the HVECU 100 determines that the vehicle speed V has decreased to the lower limit vehicle speed VL, the HVECU 100 drives the engine 2 and the motor MG2 with the engine output Pe ₂ and the motor output Pm ₂ respectively (step S15), and ends this process. That is, the HVECU 100 shifts the hybrid vehicle 1 from coasting to acceleration traveling on the condition that the vehicle speed V has reached the lower limit vehicle speed VL.

On the other hand, if the HVECU 100 determines in step S14 that the vehicle speed V has not decreased to the lower limit vehicle speed VL, the HVECU 100 holds the driving state of the engine 2 (engine state) and the driving state of the motor MG2 (motor state), respectively. (Step S16), the process ends. That is, if the hybrid vehicle 1 is accelerating, the drive of the engine 2 at the engine output Pe ₂ is maintained and the drive of the motor MG2 at the motor output Pm ₂ is maintained. On the contrary, if the hybrid vehicle 1 is coasting, the driving stop of the engine 2 and the motor MG2 is maintained.

Here, in FIGS. 5A and 5B, the acceleration travel duration in the warm-up intermittent travel mode is tm ₁ and the inertia travel duration t _1, and the acceleration travel duration in the normal intermittent travel mode is tm. ₂ , te ₂ , the inertial running duration is t ₂ . In order to equalize the duration time of the acceleration running and the inertia running in the warm-up intermittent running mode and the normal intermittent running mode, the duration tm ₁ is made equal to the durations tm ₂ and te ₂ and the duration t ₁ is continued. to match the time _{t 2.}

  As described above, the vehicle control apparatus 4 according to the present embodiment determines that the warm-up has been completed on the condition that the coolant temperature Tw has reached the target warm-up temperature To, and the warm-up intermittent running is determined. The mode is switched to the normal intermittent running mode. Therefore, the driving state of the engine 2 and the motor MG2 can be suitably controlled according to whether or not the three-way catalyst 29a has been warmed up, and the purification capacity of the three-way catalyst 29a, the operation efficiency of the engine 2 and the like are taken into consideration. Intermittent running can be realized. As a result, the vehicle control device 4 according to the present embodiment can achieve both improvement in fuel consumption and improvement in exhaust emission.

  Further, since the vehicle control device 4 according to the present embodiment causes the engine 2 to operate independently even during inertial running in the warm-up intermittent running mode, warm-up of the three-way catalyst 29a can be promoted.

  In the present embodiment, the vehicle speed V at the time when the user required power P becomes substantially constant in the intermittent travel control is set as the control vehicle speed VS, and the vehicle speed side is increased by a predetermined vehicle speed based on the control vehicle speed VS. The upper limit vehicle speed VH and the lower limit vehicle speed VL are set on the low vehicle speed side, but the present invention is not limited to this. For example, the vehicle speed V when the user request power P becomes substantially constant is set as the upper limit vehicle speed VH. The lower limit vehicle speed VL, the vehicle speed range R, and the control vehicle speed VS may be set based on the above. Specifically, the HVECU 100 sets the lower limit vehicle speed VL by subtracting a predetermined vehicle speed from the upper limit vehicle speed VH simultaneously with or after the setting of the upper limit vehicle speed VH. Further, the HVECU 100 sets the control vehicle speed VS on the low vehicle speed side by a predetermined vehicle speed from the upper limit vehicle speed VH simultaneously with or after the setting of the upper limit vehicle speed VH and the lower limit vehicle speed VL. At this time, it is preferable that the control vehicle speed VS is set between the upper limit vehicle speed VH and the lower limit vehicle speed VL.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS.

  In particular, the present embodiment is different from the above-described first embodiment in the control content of the warm-up / intermittent travel mode, but the other configurations are the same. Therefore, the same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted.

  The HVECU 100 according to the present embodiment is configured to vary the engine output Pe of the engine 2 during acceleration traveling based on the coolant temperature Tw during execution of the warm-up intermittent traveling mode.

  Specifically, as shown in FIG. 8, the HVECU 100 sets an output upper limit value P_limit of the engine 2 in accordance with the coolant temperature Tw. The output upper limit value P_limit is set so as to increase as the physical quantity correlated with the warming-up progress state of the three-way catalyst 29a increases, that is, as the cooling water temperature Tw increases. Further, the output upper limit value P_limit is determined, for example, by referring to a relationship map between the coolant temperature Tw and the output upper limit value P_limit that is experimentally obtained and stored in advance.

  Here, the output upper limit value P_limit is set to a value that can maintain the purification ability of the three-way catalyst 29a. That is, the output upper limit value P_limit is sufficient even if the engine 2 is operated at the output upper limit value P_limit. The three-way catalyst 29a is sufficiently capable of carbon monoxide (CO), hydrocarbons (HC), nitrogen oxides (NOx) in the exhaust gas. ) Is set as the purifiable engine output Pe, and can be determined by the performance of the engine 2 and the performance of the three-way catalyst 29a.

  The output upper limit value P_limit is set to increase stepwise as the cooling water temperature Tw increases because the purification capacity of the three-way catalyst 29a increases as the warm-up progresses. Note that the output upper limit value P_limit is not limited to being set stepwise as shown in FIG. 8, but may be set steplessly in correlation with the cooling water temperature Tw, for example.

The HVECU 100 is configured to vary the engine output Pe within a range that does not exceed the output upper limit value P_limit during execution of the warm-up intermittent running mode. For example, as shown in FIG. 8, during the elapsed time S _{1 to the} elapsed time S ₂ , the engine 2 is at a relatively low temperature at the initial warm-up time. At the initial warm-up time, since the thermal efficiency is low and the operation efficiency of the engine 2 is reduced, the engine output Pe is set to the motor output Pm ₁ as the engine output Pe_idle. That is, in the initial warm-up period, intermittent running is performed by the motor output Pm ₁ .

On the other hand, after the elapsed time S ₂ , the warm-up progresses and the engine 2 is also relatively warm. Therefore, even when the engine output Pe is used during intermittent running, the operating efficiency decreases as in the initial warm-up. There is no. Therefore, in this case, the engine output Pe is used within a range that does not exceed the output upper limit value P_limit, and intermittent traveling is performed by the motor output Pm that supplements the engine output Pe.

  In the present embodiment, for example, a reference water temperature Tt, which will be described later, is used as a reference for determining whether or not the operation efficiency of the engine 2 is reduced during the execution of the warm-up intermittent running mode.

  Next, the intermittent travel control during execution of the catalyst warm-up control according to the present embodiment will be described.

  The process flow of the intermittent traveling control shown in FIGS. 6 and 7 is executed at predetermined time intervals while the hybrid vehicle 1 is traveling. In particular, this processing flow is executed during execution of catalyst warm-up control. Also, Steps S21 to S36 shown in FIG. 7 are substantially the same as Steps S1 to S4 and Steps S11 to S20 shown in FIG. 3 in the first embodiment. Therefore, in the following, each step after step S41 different from the first embodiment will be described. However, step S35 is partially different, and will be described later.

  As shown in FIGS. 6 and 7, when the HVECU 100 determines that the coolant temperature Tw is not equal to or higher than the target warm-up temperature To (NO in step S24), the warm-up intermittent running mode is executed (step S41). .

In the warm-up intermittent running mode in the present embodiment, during acceleration running, the engine output Pe is made variable as the engine output Pe_idle or the engine output Pe ₄ according to the progress state of the warm-up, and the motor output Pm is changed accordingly. It is assumed that the motor output Pm _{1 to the} motor output Pm ₄ . On the other hand, during coasting, the engine output Pe is set to the engine output Pe_idle and the motor output Pm is set to zero.

  As described above, in the warm-up / intermittent running mode in the present embodiment, intermittent running is performed by the driving force of only the motor MG2 or intermittent driving is performed by the driving force of the engine 2 and the motor MG2 in accordance with the progress state of the warm-up. It is decided whether to do. Note that the engine output Pe during coasting is not limited to the engine output Pe_idle, and may be a relatively low load engine output that does not exceed the purification capacity of the three-way catalyst 29a.

  Next, the HVECU 100 determines in step S42 whether or not the vehicle speed V has increased to the upper limit vehicle speed VH. If the HVECU 100 determines that the vehicle speed V has increased to the upper limit vehicle speed VH, the HVECU 100 continues the self-sustained operation of the engine 2 and stops driving the motor MG2 (step S43), thereby ending this process. That is, the HVECU 100 shifts the hybrid vehicle 1 from the acceleration traveling to the inertia traveling on the condition that the vehicle speed V has reached the upper limit vehicle speed VH.

  On the other hand, if it is determined in step S42 that the vehicle speed V has not increased to the upper limit vehicle speed VH, the HVECU 100 determines whether or not the vehicle speed V has decreased to the lower limit vehicle speed VL (step S44). When it is determined that the vehicle speed V has decreased to the lower limit vehicle speed VL, the HVECU 100 determines whether or not the cooling water temperature Tw is equal to or higher than the reference water temperature Tt (step S45). Here, the reference water temperature Tt is a water temperature in consideration of the operation efficiency of the engine 2. For example, when the water temperature is lower than the reference water temperature Tt, the warm-up is insufficient and the heat efficiency is low. Intermittent running is performed by the motor output Pm.

If the HVECU 100 determines that the cooling water temperature Tw is not equal to or higher than the reference water temperature Tt, the HVECU 100 continues the self-sustaining operation of the engine 2 and drives the motor MG2 with the motor output Pm ₁ (step S46), thereby ending this process. That is, the HVECU 100 shifts the hybrid vehicle 1 from coasting to acceleration traveling on the condition that the vehicle speed V has reached the lower limit vehicle speed VL.

On the other hand, when the HVECU 100 determines that the cooling water temperature Tw is equal to or higher than the reference water temperature Tt, the HVECU 100 drives the engine 2 with the engine output Pe ₂ or the engine output Pe ₄ that is equal to or less than the output upper limit value P_limit, and the user requested power P to allow the output to end the driving of the motor MG2 (step S47) the processing by the motor output Pm ₂ to the motor output Pm ₄ necessary to supplement the engine output Pe ₂ to the engine output Pe _4.

On the other hand, if the HVECU 100 determines in step S44 that the vehicle speed V has not decreased to the lower limit vehicle speed VL, the HVECU 100 maintains the driving state of the engine 2 (engine state) and the driving state of the motor MG2 (motor state), respectively. (Step S48), the process is terminated. That is, if the hybrid vehicle 1 is accelerating while the cooling water temperature Tw is lower than the reference water temperature Tt, the self-sustaining operation of the engine 2 is maintained and the driving of the motor MG2 at the motor output Pm ₁ is maintained. Further, if the hybrid vehicle 1 is accelerating while the cooling water temperature Tw is equal to or higher than the reference water temperature Tt, the engine 2 is maintained driven by the engine output Pe _{2 to the} engine output Pe ₄ and the motor output Pm ₂ to maintaining the driving of the motor MG2 at the motor output Pm _4. On the contrary, if the hybrid vehicle 1 is coasting, the engine 2 is maintained on its own and the motor MG2 is stopped.

  By the way, in step S35 shown in FIG. 6 of the present embodiment, as in the first embodiment, the HVECU 100 cooperates the engine 2 and the motor MG2 so that a desired driving force is generated based on the user request power P. Drive. However, in the motor travel mode, only the motor MG2 is driven to generate a desired driving force based on the user request power P. Further, when the warm-up of the three-way catalyst 29a is not completed, it is appropriate to drive only the motor MG2 or to drive the engine 2 and the motor MG2 in a coordinated manner according to the progress state of the warm-up. Selected.

  Next, with reference to the time chart shown in FIG. 8, the intermittent traveling during execution of the warm-up intermittent traveling mode in the present embodiment will be described.

As shown in FIG. 8, until the elapsed time _{S 1,} the cooling water temperature Tw is low, the engine 2 is autonomous operation in the engine output Pe_idle. Then, upon reaching the age S _1, the cooling water temperature Tw with the progress of warming-up is increased, the output upper limit value P_limit ₁ of the engine 2 is set accordingly. Here, the output upper limit value P_limit ₁ is set to a value larger than the engine output Pe_idle. However, since the cooling water temperature Tw is still lower than the reference water temperature Tt, the thermal efficiency is also low. Therefore, since the output upper limit value P_limit ₁ which may rather be driven engine 2 decreases the operating efficiency of the engine 2, the elapsed time until S ₂ in consideration of the fuel consumption to drive the motor MG2 by the motor output Pm ₁ . That is, a desired driving force based on the user request power P is generated by the motor output Pm ₁ of the motor MG2. At this time, the engine 2 is continuously operated independently with the engine output Pe_idle.

Then, upon reaching the age _{S 2,} a large output upper limit value P_limit ₂ is set than the output upper limit value P_limit _1. At this time, the cooling water temperature Tw becomes equal to or higher than the reference water temperature Tt as the warm-up progresses. Thus, during the elapsed time _{S 2} to the elapsed time _{S 3,} the engine output Pe during acceleration running is the output upper limit value P_limit ₂ equivalent engine output Pe _2. At this time, the motor output Pm is set to a motor output Pm ₂ smaller than the motor output Pm ₁ so as to generate a driving force that is insufficient for the engine output Pe ₂ .

Thereafter, upon reaching the age _{S 3,} a large output upper limit value P_limit ₃ is set than the output upper limit value P_limit _2. Therefore, during the elapsed time S _{3 to the} elapsed time S ₄ , the engine output Pe during acceleration traveling is set to the engine output Pe ₃ equivalent to the output upper limit value P_limit ₃ . At this time, the motor output Pm is set to a motor output Pm ₃ smaller than the motor output Pm ₂ so as to generate a driving force that is insufficient for the engine output Pe ₃ .

Next, when the elapsed time reaches the _{S 4,} large output upper limit P_limit ₄ is set than the output upper limit value P_limit _3. Thus, during the elapsed time _{S 4} to the elapsed time _{S 5} is the engine output Pe during acceleration traveling can be outputted to the output upper limit value P_limit _4, the engine output Pe in consideration of fuel consumption than the output upper limit value P_limit ₄ A small engine output Pe ₄ is set. At this time, the motor output Pm is set to the motor output Pm ₄ corresponding to the distribution ratio between the engine 2 and the motor MG2.

Thereafter, upon reaching the age S _5, the cooling water temperature Tw reaches the target warm-up water temperature To, the warm-up of the three-way catalyst 29a is completed. At the same time, the engine output Pe during inertia traveling is set to zero from the engine output Pe_idle. Thus, thereafter (time elapsed S ₅ or later), along it generates a driving force during the acceleration running in the engine output Pe ₄ and the motor output Pm _4, usually to the engine output Pe and the motor output Pm during coasting zero Transition to intermittent driving mode.

The engine output Pe _{2 to the} engine output Pe ₄ in the time chart shown in FIG. 8 described above are examples and are not limited to these. That is, the engine output Pe _{2 to the} engine output Pe ₄ are in a range that does not exceed the output upper limit value P_limit depending on the traveling state of the hybrid vehicle 1 such as whether the vehicle is traveling at low speed or high speed, the specification value of the engine 2, and the like. As appropriate, it is set to an optimum value.

  As described above, the vehicle control apparatus 4 according to the present embodiment determines that the warm-up has been completed on the condition that the coolant temperature Tw has reached the target warm-up temperature To, and the warm-up intermittent running is determined. The mode is switched to the normal intermittent running mode. Further, during execution of the warm-up intermittent running mode, the engine output Pe during acceleration running is varied based on the coolant temperature Tw.

Thus, for example, warming up the initial time (e.g., elapsed time S ₁ to the elapsed time S ₂ shown in FIG. ₈₎ in the case of intermittently driving the hybrid vehicle 1 is at a low temperature range such as, operating efficiency of the engine 2 low thermal efficiency Therefore, intermittent running can be performed by the motor output Pm of the motor MG2 regardless of the engine output Pe of the engine 2. Thereby, the fuel consumption at the initial stage of warm-up is improved. On the other hand, as the warm-up progresses, the cooling water temperature Tw rises and the purification capacity of the three-way catalyst 29a also increases, so that the engine output Pe can be output within a range not exceeding this purification capacity. In this case, intermittent traveling can be performed using the outputs of the engine 2 and the motor MG2 while maintaining the purification capability of the three-way catalyst 29a.

  Therefore, the vehicle control device 4 according to the present embodiment can suitably control the outputs of the engine 2 and the motor MG2 in accordance with the warming-up progress state, and achieves both improvement in fuel consumption and improvement in exhaust emission. You can plan.

  Further, in the vehicle control device 4 according to the present embodiment, the engine output Pe is variable in a range that does not exceed the output upper limit value P_limit of the engine 2 that increases as the cooling water temperature Tw increases during the warm-up intermittent running mode. Is done. For this reason, it is suppressed that the engine output Pe which exceeds the purification capacity of the three-way catalyst 29a which increases with the progress of warm-up is output.

  In the present embodiment, the HVECU 100 sets the output upper limit value P_limit according to the cooling water temperature Tw. However, as shown in FIG. 8, for example, according to the difference ΔT between the cooling water temperature Tw and the target warm-up temperature To. The output upper limit value P_limit may be set. Specifically, the output upper limit value P_limit is set to increase as the difference ΔT decreases. Even in this case, the same effect as the above-described embodiment can be obtained.

  As described above, the vehicle control device according to the present invention can achieve both improvement in fuel consumption and improvement in exhaust emission, and is applied to a vehicle that includes an internal combustion engine and an electric motor as driving force sources. Useful for control devices.

1 Hybrid vehicle (vehicle)
2 Engine (Internal combustion engine)
4 Vehicle control device 28 Exhaust passage 29a Three-way catalyst (catalyst)
60 motor ECU
100 HVECU (control means)
200 Engine ECU
MG2 motor (electric motor)

Claims (6)

A driving force source that generates a driving force of a vehicle includes an internal combustion engine and an electric motor, and a catalyst provided on an exhaust passage of the internal combustion engine. A vehicle control device for use in a vehicle capable of intermittent traveling by repeatedly performing inertial traveling that travels inertially without outputting a driving force in a vehicle speed range determined according to the vehicle speed,
The internal combustion engine is operated independently at a predetermined rotational speed to warm up the catalyst, and the intermittent driving is executed using the driving force generated by the electric motor or the driving force generated by the electric motor and the internal combustion engine. A warm-up intermittent running mode, and a normal intermittent running mode in which the intermittent running is performed using the driving force generated by the internal combustion engine and the electric motor, and a physical quantity correlated with the warm-up progress state is set in advance. It is determined that the warm-up has been completed on the condition that the set target value has been reached, and includes control means for switching from the warm-up intermittent running mode to the normal intermittent running mode,
The control device varies the engine output of the internal combustion engine during acceleration traveling based on the physical quantity during execution of the warm-up intermittent traveling mode.   The control means sets an output upper limit value of the internal combustion engine that increases as the physical quantity increases, and varies the engine output within a range not exceeding the output upper limit value during execution of the warm-up intermittent running mode. The vehicle control device according to claim 1.   The control means sets an output upper limit value of the internal combustion engine that increases as the difference between the physical quantity and the target value decreases, and the engine is within a range not exceeding the output upper limit value during execution of the warm-up intermittent running mode. The vehicle control device according to claim 1, wherein the output is variable.   4. The vehicle control device according to claim 2, wherein the output upper limit value is set to a value capable of maintaining the purification ability of the catalyst. 5.   5. The vehicle control device according to claim 1, wherein the control unit causes the internal combustion engine to operate independently during inertial traveling in the warm-up intermittent traveling mode.   6. The control unit according to claim 1, wherein the control unit uses any one of a cooling water temperature of the internal combustion engine, a temperature of the catalyst, and an oil temperature of the internal combustion engine as the physical quantity. The vehicle control device according to claim 1.

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