JP2009262753A - Hybrid car and its control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance energy efficiency while securing motive power performance of a hybrid car by more properly using exhaust gas reflux, and more properly controlling an internal combustion engine. <P>SOLUTION: In the hybrid car 20, when a normal mode in which fuel consumption is given priority to an operation mode according to the accelerating operation of a driver, an engine 22 is driven accompanying both an exhaust gas reflux through an EGR valve 143 and fuel injection in fuel injection timing to be determined according to a map for setting an injection end period for the normal mode (S140 to S160 or the like). Also, when a power mode in which a torque output is given priority is set to the operation mode according to the accelerating operation of the driver, the engine 22 is driven not accompanying the exhaust gas reflux via the EGR valve 143 but accompanying the fuel injection in the fuel injection timing to be determined according to the map for setting the injection end period for the power mode (S170 to S190 or the like). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a hybrid vehicle and a control method thereof.

2. Description of the Related Art Conventionally, an internal combustion engine including an EGR valve for returning a part of exhaust gas discharged from an exhaust passage to an intake passage pipe is known (for example, see Patent Document 1). In this internal combustion engine, when the exhaust gas is recirculated to the intake passage via the EGR valve, the fuel injection start timing is set before the top dead center of the intake stroke as the exhaust gas recirculation amount increases, or The fuel injection end time is set to the advance side. As a result, when the exhaust gas recirculation is performed, the fuel injection time in the intake stroke becomes shorter as the exhaust gas recirculation amount increases, and the residence time of the injected fuel at the intake port becomes longer as the exhaust gas recirculation amount increases. Vaporization can be promoted, and deterioration of combustion accompanying exhaust gas recirculation can be suppressed.
JP-A 63-68729

  By the way, if the internal combustion engine having the exhaust gas recirculation device as described above is applied to a so-called hybrid vehicle, the fuel efficiency (fuel consumption rate) of the internal combustion engine can be further improved and the energy efficiency of the entire vehicle can be further improved. Conceivable. However, exhaust gas recirculation has the effect of reducing NOx and improving fuel efficiency, while also having a possibility of causing a slight decrease in power performance due to deterioration of combustion. Therefore, when an internal combustion engine having an exhaust gas recirculation device is mounted on a hybrid vehicle, exhaust gas recirculation is more appropriately used so that fuel efficiency, that is, energy efficiency of the vehicle, can be improved while ensuring power performance of the vehicle. There is a need to control the internal combustion engine more appropriately.

  Accordingly, the present invention improves energy efficiency while ensuring the power performance of a vehicle by ensuring proper use of exhaust gas recirculation and more appropriate control of the internal combustion engine in a hybrid vehicle equipped with an internal combustion engine having exhaust gas recirculation means. The main purpose is to

  The hybrid vehicle and its control method according to the present invention employ the following means in order to achieve the above-mentioned main object.

The hybrid vehicle according to the present invention is
An internal combustion engine having exhaust gas recirculation means for recirculating exhaust gas from the exhaust system to the intake system;
Power power input / output means connected to the engine shaft of the internal combustion engine and a predetermined axle for transmitting power to the drive wheels and for inputting / outputting power to / from the engine shaft and the axle with input / output of power and power When,
An electric motor capable of outputting power to the axle or another axle different from the axle;
A power storage means capable of exchanging power with the power input / output means and the electric motor;
A required driving force setting means for setting a required driving force required for traveling;
Mode determining means for determining which one of the first mode prioritizing energy efficiency and the second mode prioritizing power performance based on a predetermined operation by the driver should be the operation mode;
When the mode determination means determines that the first mode should be the operation mode, the exhaust gas recirculation by the exhaust gas recirculation means and the fuel injection at the fuel injection timing determined according to the first injection timing setting constraint The internal combustion engine is operated, and the internal combustion engine, the power power input / output means, and the electric motor are controlled so that power based on the set required driving force is obtained, and the mode determination means When it is determined that the second mode should be the operation mode, the fuel injection is determined according to a second injection timing setting constraint different from the first injection timing setting constraint without the exhaust gas recirculation. The internal combustion engine is operated with fuel injection at a timing, and power based on the set required driving force is obtained. And control means for controlling said electric motor and the electric power-mechanical power input output means;
Is provided.

  In this hybrid vehicle, when the first mode giving priority to energy efficiency in accordance with a predetermined operation by the driver is to be the operation mode, it is determined according to the exhaust gas recirculation by the exhaust gas recirculation means and the first injection timing setting restriction. The internal combustion engine, the power drive input / output means, and the electric motor are controlled so that the internal combustion engine is operated with fuel injection at the fuel injection timing and power based on the required driving force required for traveling is obtained. In addition, when the second mode in which power performance is prioritized according to the driver's predetermined operation is to be the operation mode, the second injection that is different from the first injection timing setting restriction without accompanying exhaust gas recirculation. The internal combustion engine, the power power input / output means, and the electric motor are controlled so that the internal combustion engine is operated with fuel injection at the fuel injection timing determined according to the timing setting constraint and power based on the required driving force is obtained. That is, in this hybrid vehicle, the first mode in which the driving mode prioritizes energy efficiency (fuel consumption) over the power performance and the second mode in which power performance is prioritized over energy efficiency in accordance with a predetermined operation by the driver. In the first mode, the exhaust gas recirculation can be used to improve the fuel efficiency of the internal combustion engine, and the second mode can be used to reduce the exhaust gas recirculation. By not using it intentionally, the power performance of the internal combustion engine can be secured better. Further, in this hybrid vehicle, in consideration of the fact that the fuel injection timing of the internal combustion engine does not always match between the case where priority is given to the fuel efficiency of the internal combustion engine and the case where priority is given to power performance, the first mode using exhaust gas recirculation is used. The first injection timing setting restriction used originally is different from the second injection timing setting restriction used under the second mode in which exhaust gas recirculation is not used. Thereby, the first injection timing setting restriction for the first mode is adapted so that the fuel efficiency of the internal combustion engine is further improved, and the power performance of the internal combustion engine is ensured satisfactorily. The second injection timing setting restriction can be adapted, and the advantages of switching between the first mode with priority on energy efficiency and the second mode with priority on power performance and the use of exhaust gas recirculation can be further promoted. it can. Therefore, in this hybrid vehicle, the exhaust gas recirculation can be used more appropriately, and the internal combustion engine can be more appropriately controlled to improve the energy efficiency while ensuring the power performance of the vehicle.

  Further, the second injection timing setting constraint may have a tendency to set the fuel injection timing to an advance side as compared with the first injection timing setting constraint. That is, in the hybrid vehicle according to the present invention, the first mode using exhaust gas recirculation is basically intended to improve energy efficiency (fuel consumption). It is not necessary to advance the fuel injection timing from the viewpoint of securing the torque of the internal combustion engine as in the case of a vehicle provided with only the power source for traveling power. Further, under the second mode that does not use exhaust gas recirculation, the torque characteristics of the internal combustion engine can be made better by advancing the fuel injection timing as appropriate. Therefore, if the second injection timing setting constraint has a tendency to set the fuel injection timing to the advance side as compared with the first injection timing setting constraint, the fuel efficiency of the internal combustion engine is improved by using exhaust gas recirculation. The first injection timing setting constraint used under the first mode and the second injection timing setting used under the second mode for ensuring the power performance of the internal combustion engine without using exhaust gas recirculation It is possible to make the constraints more appropriate according to the main purpose of each operation mode.

  Furthermore, the first and second injection timing setting constraints may be a constraint that defines a relationship between the rotational speed of the engine shaft and the fuel injection end timing of the internal combustion engine. In this way, by defining the fuel injection end timing for each engine shaft speed, the main injection timing can be set so that the occurrence of knocking is suppressed in the first and second injection timing setting constraints. It can be more appropriate for the purpose.

  In addition, when the mode determination unit determines that the first mode should be the operation mode, the control unit uses a first operation point setting constraint that prioritizes the fuel consumption of the internal combustion engine. The target operating point of the internal combustion engine corresponding to the set required driving force is set, and the setting is performed with the exhaust gas recirculation and fuel injection at a fuel injection timing determined according to the first injection timing setting constraint The internal combustion engine is operated at the set target operation point, and the internal combustion engine, the power power input / output means, and the electric motor are controlled so that power based on the set required driving force is obtained, and the mode determination is performed When it is determined by the means that the second mode should be the operation mode, a second operation point setting that gives priority to the power performance of the internal combustion engine is set. The target operating point of the internal combustion engine corresponding to the set required driving force is set using about, and the fuel at the fuel injection timing determined according to the second injection timing setting constraint without accompanying the exhaust gas recirculation The internal combustion engine, the power power input / output means, and the electric motor are operated so that the internal combustion engine is operated at the set target operation point with injection and power based on the set required driving force is obtained. It may be controlled. That is, in the hybrid vehicle according to the present invention, the power based on the driving force required for traveling is output to the axle or the like while arbitrarily setting the operating point of the internal combustion engine by appropriately controlling the power power input / output means and the electric motor. be able to. Therefore, the first operating point setting restriction used under the first mode for improving the fuel efficiency of the internal combustion engine by using exhaust gas recirculation, and the second for ensuring the power performance of the internal combustion engine without using exhaust gas recirculation. If the second driving point setting constraints used under the first mode are adapted to match the main purpose of the corresponding driving mode, the fuel efficiency is further improved under the first mode. As described above, the internal combustion engine can be controlled and the internal combustion engine can be controlled so as to ensure good power performance under the second mode.

  Further, the predetermined operation may be an operation of depressing an accelerator pedal, and the mode determination means sets the first mode as the operation mode when an accelerator operation amount by a driver is less than a predetermined threshold. It may be determined that the second operation mode should be the operation mode when the accelerator operation amount by the driver is equal to or greater than the threshold value. As a result, when it is assumed that the accelerator operation amount (depression amount) by the driver is relatively small and the driver prioritizes (requests) improvement in energy efficiency (fuel consumption) over power performance, a hybrid vehicle Can be run under the first mode so as to improve energy efficiency. Conversely, if the driver's accelerator operation amount is relatively large and the driver is assumed to prioritize power performance over energy efficiency, the hybrid vehicle will have good power performance. The vehicle can be driven under the second mode.

  In addition, when the mode determination unit determines that the first mode should be the driving mode, the required driving force setting unit uses the first driving force setting constraint to perform an accelerator operation by the driver. When the required driving force corresponding to the amount is set and the mode determining means determines that the second mode should be the operating mode, it is the same as the first driving force setting constraint. The requested driving force corresponding to the accelerator operation amount by the driver may be set using a second driving force setting constraint that tends to set the required driving force with respect to the accelerator operation amount large. Even if such a configuration is adopted, by using exhaust gas recirculation more appropriately and controlling the internal combustion engine more appropriately, energy efficiency is improved under the first mode and under the second mode. It becomes possible to ensure good power performance.

  In this case, when the mode determination unit determines that the first mode should be the operation mode, the control unit efficiently operates the set required driving force and the internal combustion engine. When setting the operation point of the internal combustion engine using an operation point setting constraint that defines the operation point, and when the mode determination means determines that the second mode should be the operation mode, Operation of the internal combustion engine using the set required driving force, the operation point setting constraint or another operation point setting constraint different from the operation point setting constraint and the lower limit rotational speed of the internal combustion engine determined according to the vehicle speed You may set a point.

  Further, the predetermined operation may be an operation of a mode selection switch that enables selection between the first mode and the second mode, and the mode determination means may be configured by the driver to select the mode selection switch. It may be determined which one of the first and second modes should be the operation mode based on the operation state. According to such a configuration, the operation state of the mode selection switch indicates the driver's intention, that is, which should be prioritized to improve the energy efficiency or secure the power performance. Further, the exhaust gas recirculation can be used more appropriately and the internal combustion engine can be more appropriately controlled to improve the energy efficiency while ensuring the power performance of the vehicle.

  The power power input / output means is connected to three shafts of a generator motor capable of inputting / outputting power, the axle, the engine shaft of the internal combustion engine, and a rotating shaft of the generator motor, and the three shafts 3 axis type power input / output means for inputting / outputting power based on the power input / output to / from any of the two axes to / from the remaining shafts.

The hybrid vehicle control method according to the present invention includes:
An internal combustion engine having exhaust gas recirculation means for recirculating exhaust gas from the exhaust system to the intake system, and a predetermined axle that transmits power to the engine shaft and drive wheels of the internal combustion engine are connected to the power and power. Power power input / output means for inputting / outputting power to / from the engine shaft and the axle with output, an electric motor capable of outputting power to the axle or another axle different from the axle, and the power power input / output means And a control method of a hybrid vehicle comprising a power storage means capable of exchanging electric power with the electric motor,
(A) determining which of the first mode that prioritizes energy efficiency and the second mode that prioritizes power performance based on a predetermined operation by the driver should be the operation mode;
(B) When it is determined in step (a) that the first mode should be the operation mode, the exhaust gas recirculation by the exhaust gas recirculation means and the fuel injection timing determined according to the first injection timing setting constraint Controlling the internal combustion engine, the power power input / output means, and the electric motor so that the internal combustion engine is operated with fuel injection at the same time and power based on the set required driving force is obtained. When it is determined in (a) that the second mode should be the operation mode, a second injection timing setting constraint different from the first injection timing setting constraint without accompanying the exhaust gas recirculation. The internal combustion engine and the internal combustion engine are operated so as to be operated with fuel injection at a fuel injection timing determined according to And controlling the a force-mechanical power input output means and said motor,
Is included.

  According to this method, the exhaust gas recirculation can be used more appropriately, and the internal combustion engine can be more appropriately controlled to ensure the power performance of the vehicle and improve the energy efficiency.

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

  FIG. 1 is a schematic configuration diagram of a hybrid vehicle 20 according to an embodiment of the present invention. A hybrid vehicle 20 shown in FIG. 1 includes an internal combustion engine device 21 including an engine 22, a three-shaft power distribution and integration mechanism 30 connected to a crankshaft (engine shaft) 26 of the engine 22 via a damper 28, A motor MG1 capable of generating electricity connected to the distribution integration mechanism 30, a reduction gear 35 connected to a ring gear shaft 32a as an axle connected to the power distribution integration mechanism 30, and a ring gear shaft 32a via the reduction gear 35. The motor MG2 is connected, and a hybrid electronic control unit (hereinafter referred to as “hybrid ECU”) 70 for controlling the entire hybrid vehicle 20 is provided.

  The engine 22 constituting the internal combustion engine device 21 explosively burns a mixture of hydrocarbon fuel such as gasoline or light oil and air in the combustion chamber 120, and cranks the reciprocating motion of the piston 121 accompanying the explosion combustion of the mixture. The engine is configured as an internal combustion engine that outputs power by converting it into a rotational motion of the shaft 26. In this engine 22, as can be seen from FIG. 2, the air purified by the air cleaner 122 is taken into the intake pipe 126 through the throttle valve 123, and fuel such as gasoline is injected from the fuel injection valve 127 into the intake air. The The mixture of air and fuel thus obtained is sucked into the combustion chamber 120 through an intake valve 131 driven by a valve operating mechanism 130 configured as a variable valve timing mechanism, and explodes by an electric spark from the spark plug 128. Burned. The exhaust gas from the engine 22 is an exhaust gas purification catalyst (three-way catalyst) that purifies harmful components such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx) through the exhaust valve 132 and the exhaust manifold 140. ) And is purified by the purification device 141 and then discharged to the outside. The internal combustion engine device 21 is connected to an exhaust pipe downstream of the purification device 141 and recirculates exhaust gas to a surge tank (intake system), and is provided in the middle of the EGR pipe 142 and is connected to the exhaust system. An EGR valve 143 that adjusts the recirculation amount (EGR amount) of exhaust gas (EGR gas) recirculated to the intake system, a temperature sensor 144 that detects the temperature of the EGR gas in the EGR pipe 142, and the like are included.

  The engine 22 configured in this way is controlled by an engine electronic control unit (hereinafter referred to as “engine ECU”) 24. As shown in FIG. 2, the engine ECU 24 is configured as a microprocessor centered on a CPU 24a. In addition to the CPU 24a, a ROM 24b that stores various processing programs, a RAM 24c that temporarily stores data, and an input (not shown). Output port and communication port. Then, signals from various sensors that detect the state of the engine 22 and the like are input to the engine ECU 24 via an input port (not shown). For example, the engine ECU 24 includes a crank position from a crank position sensor 180 that detects the rotational position of the crankshaft 26, a cooling water temperature Tw from a water temperature sensor 181 that detects the temperature of cooling water in the engine 22, and a pressure in the combustion chamber 120. A cylinder position from a cylinder pressure sensor 182 that detects the rotational position of a camshaft included in a valve operating mechanism 130 that drives the intake valve 131 and the exhaust valve 132; The throttle position from the throttle valve position sensor 124 for detecting the position of the engine, the intake air amount GA from the air flow meter 183 for detecting the intake air amount as a load of the engine 22, and the intake air temperature sensor 184 attached to the intake pipe 126 Intake air temperature Air, intake negative pressure Pi from the intake pressure sensor 185 for detecting the negative pressure in the intake pipe 126, air-fuel ratio AF from the air-fuel ratio sensor 186 disposed upstream of the purification device 141 of the exhaust manifold 140, EGR pipe 142 The EGR gas temperature from the temperature sensor 144 is input via the input port. The engine ECU 24 outputs various control signals for driving the engine 22 through an output port (not shown). For example, the engine ECU 24 sends a drive signal to the fuel injection valve 127, a drive signal to the throttle motor 125 that adjusts the position of the throttle valve 123, a control signal to the ignition coil 129 integrated with the igniter, and the valve mechanism 130. Control signal, a drive signal to the EGR valve 143, and the like are output via an output port. Further, the engine ECU 24 is in communication with the hybrid ECU 70, controls the operation of the engine 22 by a control signal from the hybrid ECU 70, and outputs data related to the operation state of the engine 22 to the hybrid ECU 70 as necessary.

  The power distribution and integration mechanism 30 includes an external gear sun gear 31, an internal gear ring gear 32 arranged concentrically with the sun gear 31, a plurality of pinion gears 33 that mesh with the sun gear 31 and mesh with the ring gear 32, A planetary gear mechanism is provided that includes a carrier 34 that holds a plurality of pinion gears 33 so as to rotate and revolve, and that performs differential action using the sun gear 31, the ring gear 32, and the carrier 34 as rotating elements. The crankshaft 26 of the engine 22 is connected to the carrier 34 as the engine side rotation element, the motor MG1 is connected to the sun gear 31, and the reduction gear 35 is connected to the ring gear 32 as the axle side rotation element via the ring gear shaft 32a. The power distribution and integration mechanism 30 distributes the power from the engine 22 input from the carrier 34 to the sun gear 31 side and the ring gear 32 side according to the gear ratio when the motor MG1 functions as a generator. When the motor functions as an electric motor, the power from the engine 22 input from the carrier 34 and the power from the motor MG1 input from the sun gear 31 are integrated and output to the ring gear 32 side. The power output to the ring gear 32 is finally output from the ring gear shaft 32a to the wheels 39a and 39b which are drive wheels via the gear mechanism 37 and the differential gear 38.

  Each of the motors MG1 and MG2 is configured as a known synchronous generator motor that operates as a generator and can operate as a motor, and exchanges power with the battery 50 that is a secondary battery via inverters 41 and 42. . The power line 54 connecting the inverters 41 and 42 and the battery 50 is configured as a positive bus and a negative bus shared by the inverters 41 and 42, and the power generated by one of the motors MG1 and MG2 is supplied to the other. It can be consumed with the motor. Therefore, the battery 50 is charged / discharged by the electric power generated from one of the motors MG1 and MG2 or the insufficient electric power. If the electric power balance is balanced by the motors MG1 and MG2, the battery 50 is charged. It will not be discharged. The motors MG1 and MG2 are both driven and controlled by a motor electronic control unit (hereinafter referred to as “motor ECU”) 40. The motor ECU 40 receives signals necessary for driving and controlling the motors MG1 and MG2, such as signals from rotational position detection sensors 43 and 44 that detect the rotational positions of the rotors of the motors MG1 and MG2, and current sensors (not shown). The detected phase current applied to the motors MG1 and MG2 is input, and the motor ECU 40 outputs a switching control signal and the like to the inverters 41 and 42. Further, the motor ECU 40 executes a rotation speed calculation routine (not shown) based on signals input from the rotation position detection sensors 43 and 44, and calculates the rotation speeds Nm1 and Nm2 of the rotors of the motors MG1 and MG2. Further, the motor ECU 40 communicates with the hybrid ECU 70, controls the driving of the motors MG1, MG2 based on the control signal from the hybrid ECU 70, and transmits data related to the operating state of the motors MG1, MG2 to the hybrid ECU 70 as necessary. Output.

  The battery 50 is managed by a battery electronic control unit (hereinafter referred to as “battery ECU”) 52. The battery ECU 52 receives signals necessary for managing the battery 50, for example, a voltage between terminals from a voltage sensor (not shown) installed between the terminals of the battery 50, and a power line 54 connected to the output terminal of the battery 50. A charging / discharging current from an attached current sensor (not shown), a battery temperature Tb from a temperature sensor 51 attached to the battery 50, and the like are input. The battery ECU 52 outputs data related to the state of the battery 50 to the hybrid ECU 70 by communication as necessary. Further, in order to manage the battery 50, the battery ECU 52 calculates the remaining capacity SOC based on the integrated value of the charging / discharging current detected by the current sensor, or requests charging / discharging of the battery 50 based on the remaining capacity SOC. The power Pb * is calculated, or the input limit Win as the charge allowable power that is the power allowed for charging the battery 50 based on the remaining capacity SOC and the battery temperature Tb, and the power allowed for discharging the battery 50. The output limit Wout as discharge allowable power is calculated. The input / output limits Win and Wout of the battery 50 set basic values of the input / output limits Win and Wout based on the battery temperature Tb, and output correction correction coefficients based on the remaining capacity (SOC) of the battery 50. It can be set by setting a correction coefficient for input restriction and multiplying the basic value of the set input / output restrictions Win and Wout by the correction coefficient.

  The hybrid ECU 70 is configured as a microprocessor centered on the CPU 72, and includes a ROM 74 for storing a processing program, a RAM 76 for temporarily storing data, an input / output port and a communication port (not shown), and the like in addition to the CPU 72. The hybrid ECU 70 detects the ignition signal from the ignition switch (start switch) 80, the shift position SP from the shift position sensor 82 that detects the shift position SP that is the operation position of the shift lever 81, and the depression amount of the accelerator pedal 83. The accelerator opening Acc from the accelerator pedal position sensor 84, the brake pedal stroke BS from the brake pedal stroke sensor 86 for detecting the depression amount of the brake pedal 85, the vehicle speed V from the vehicle speed sensor 87, and the like are input via the input port. . As described above, the hybrid ECU 70 is connected to the engine ECU 24, the motor ECU 40, the battery ECU 52, etc. via the communication port, and exchanges various control signals and data with the engine ECU 24, the motor ECU 40, the battery ECU 52, etc. ing.

  In the hybrid vehicle 20 of the embodiment configured as described above, the torque to be output to the ring gear shaft 32a as the axle is based on the accelerator opening Acc and the vehicle speed V corresponding to the depression amount of the accelerator pedal 83 by the driver. A certain required torque Tr * is calculated, and the engine 22, the motor MG1, and the motor MG2 are controlled so that torque based on the required torque Tr * is output to the ring gear shaft 32a. As a control mode of the engine 22, the motor MG1, and the motor MG2, the operation of the engine 22 is controlled so that power corresponding to the required torque Tr * is output from the engine 22, and all of the power output from the engine 22 is power distribution integrated. Necessary for torque conversion operation mode for driving and controlling motors MG1 and MG2 so that torque is converted by mechanism 30, motor MG1 and motor MG2 and output to ring gear shaft 32a, and required torque Tr * and charge / discharge of battery 50 The engine 22 is operated and controlled so that power corresponding to the sum of the electric power is output from the engine 22, and all or part of the power output from the engine 22 with charging / discharging of the battery 50 is performed by the power distribution and integration mechanism 30. Torque required with torque conversion by motor MG1 and motor MG2 A charge / discharge operation mode in which the motors MG1 and MG2 are driven and controlled so that a torque corresponding to r * is output to the ring gear shaft 32a. The operation of the engine 22 is stopped, and the power corresponding to the required torque Tr * is supplied from the motor MG2. There is a motor operation mode in which operation control is performed so that the output is output.

  Next, the operation when the hybrid vehicle 20 of the embodiment configured as described above is traveling will be described. FIG. 3 is a flowchart illustrating an example of a drive control routine that is executed at predetermined time intervals (for example, every several milliseconds) by the hybrid ECU 70 of the embodiment when the hybrid vehicle 20 is traveling with the operation of the engine 22. It is.

  At the start of the drive control routine shown in FIG. 3, the CPU 72 of the hybrid ECU 70 determines the accelerator opening Acc from the accelerator pedal position sensor 84, the vehicle speed V from the vehicle speed sensor 87, the rotational speeds Nm 1 and Nm 2 of the motors MG 1 and MG 2, Input processing of data required for control, such as required discharge power Pb * and input / output limits Win and Wout of the battery 50, is executed (step S100). Here, the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 are input from the motor ECU 40 through communication, and the charge / discharge request power Pb * and the input / output limits Win and Wout are input from the battery ECU 52 through communication. . After the data input process of step S100, the required torque Tr * to be output to the ring gear shaft 32a as the axle connected to the wheels 39a and 39b as drive wheels is set based on the input accelerator opening Acc and the vehicle speed V. After that, the required power P * required for the entire vehicle is set (step S110). In the embodiment, the relationship among the accelerator opening Acc, the vehicle speed V, and the required torque Tr * is determined in advance and stored in the ROM 74 as a required torque setting map. The required torque Tr * is the given accelerator opening. The one corresponding to Acc and the vehicle speed V is derived and set from the map. FIG. 4 shows an example of the required torque setting map. In the embodiment, the required power P * is calculated as the sum of the set required torque Tr * multiplied by the rotation speed Nr of the ring gear shaft 32a, the charge / discharge required power Pb *, and the loss Loss. The rotational speed Nr of the ring gear shaft 32a can be obtained by dividing the rotational speed Nm2 of the motor MG2 by the gear ratio Gr of the reduction gear 35 as shown in the figure or by multiplying the vehicle speed V by the conversion factor k.

  Next, the mode determination threshold value Accref is set based on the vehicle speed V input in step S100 (step S120). The mode determination threshold value Accref is a normal value that gives priority to fuel efficiency (energy efficiency) over the torque output of the engine 22 in the operation mode of the hybrid vehicle 20 by comparison with the accelerator opening degree Acc indicating the accelerator operation amount (depression amount) by the driver. This mode is used to determine which mode and power mode that prioritizes torque output over improvement in fuel efficiency of the engine 22. In the embodiment, the relationship between the vehicle speed V and the mode determination threshold value Accref is determined in advance and stored in the ROM 74 as a mode determination threshold setting map (not shown). The mode determination threshold value Accref corresponds to the given vehicle speed V. Things are derived and set from the map. Note that the mode determination threshold value Accref may be set to a value of about 50 to 70%, for example, and may be set to a larger value as the accelerator opening degree Acc is smaller. If mode determination threshold value Accref is set, it is determined whether or not accelerator opening degree Acc input in step S100 is less than mode determination threshold value Accref (step S130). If it is determined in step S130 that the accelerator opening degree Acc is less than the mode determination threshold value Accref, the amount of accelerator depression by the driver is relatively small, so that the driver applies to the ring gear shaft 32a as an axle. On the other hand, it is assumed that a large torque output is not required. Therefore, when the accelerator opening degree Acc is less than the mode determination threshold value Accref, a predetermined driving mode flag Fmod is set to a value of 0 to set the driving mode of the hybrid vehicle 20 to the normal mode with priority on fuel consumption (step S140). Further, a predetermined EGR flag Fegr is set to a value 1 so that exhaust gas recirculation through the EGR valve 143 is executed in order to improve the fuel consumption of the engine 22 (step S150), and is a target operating point of the engine 22. A fuel efficiency priority operation line (first operation point setting constraint) that defines an operation point at which the engine 22 is efficiently operated is set as an engine operation line used for setting the target rotational speed Ne * and the target torque Te * (step 1). S160). On the other hand, when it is determined in step S130 that the accelerator opening Acc is equal to or greater than the mode determination threshold value Accref, the amount of accelerator depression by the driver is relatively large. It is assumed that a relatively large torque output is required for the ring gear shaft 32a. Therefore, when the accelerator opening degree Acc is equal to or greater than the mode determination threshold value Accref, the operation mode flag Fmod is set to a value 1 in order to set the operation mode of the hybrid vehicle 20 to the torque priority power mode (step S170). Further, the EGR flag Fegr is set to a value of 0 so that exhaust gas recirculation through the EGR valve 143 is not executed (step S180), and a torque priority operation line that prioritizes torque output over the fuel consumption of the engine 22 as an engine operation line. (Second operation point setting restriction) is set (step S190).

  If the process of step S160 or S190 is executed, the target rotational speed Ne * and the target torque Te * that are target operating points of the engine 22 are set based on the required power P * set in step S110 (step S200). ). That is, when the fuel efficiency priority operation line is set as the engine operation line in step S160, in step S200, the target rotational speed Ne * and the target torque Te * are determined based on the fuel efficiency priority operation line illustrated in FIG. It is obtained as an intersection of the correlation curve indicating that the required power P * (Ne * × Te *) is constant. Further, when the torque priority operation line is set as the engine operation line in step S190, in step S200, the target rotation speed Ne * and the target torque Te * are set to the torque priority operation line illustrated in FIG. (Refer to a solid line) and an intersection of the correlation curve indicating that the required power P * is constant. As shown in the figure, the torque priority operation line of the embodiment has a target rotational speed Ne * so that a relatively large torque is output from the engine 22 while maintaining a relatively good efficiency (fuel consumption) in the normal rotational speed range. And the target torque Te *. Further, the fuel efficiency priority operation line of the embodiment has a target so that the torque output from the engine 22 is slightly suppressed in order to improve the fuel efficiency as much as possible in a relatively high rotational speed range of a predetermined rotational speed Nref (for example, 4000 to 5000 rpm) or less. The relationship between the rotational speed Ne * and the target torque Te * is defined.

  After setting the target rotational speed Ne * and the target torque Te * of the engine 22 in this way, the target rotational speed Ne *, the rotational speed Nr (Nm2 / Gr) of the ring gear shaft 32a, and the gear ratio ρ (sun gear) of the power distribution and integration mechanism 30 are set. The number of teeth of 31 / the number of teeth of the ring gear 32) is used to calculate the target rotational speed Nm1 * of the motor MG1 according to the following equation (1), and then the target torque Te *, the calculated target rotational speed Nm1 *, A torque command Tm1 * for the motor MG1 is set according to the following equation (2) using the rotational speed Nm1 and the like (step S210). Here, Expression (1) is a dynamic relational expression for the rotating element of the power distribution and integration mechanism 30. FIG. 6 illustrates a collinear diagram showing a dynamic relationship between the rotational speed and torque in the rotary element of the power distribution and integration mechanism 30. In the figure, the left S-axis indicates the rotational speed of the sun gear 31 that matches the rotational speed Nm1 of the motor MG1, the central C-axis indicates the rotational speed of the carrier 34 that matches the rotational speed Ne of the engine 22, and the right R-axis. The axis indicates the rotational speed Nr of the ring gear 32 obtained by dividing the rotational speed Nm2 of the motor MG2 by the gear ratio Gr of the reduction gear 35. The two thick arrows on the R axis indicate the torque acting on the ring gear shaft 32a by this torque output when the motor MG1 outputs the torque Tm1, and the reduction gear 35 when the motor MG2 outputs the torque Tm2. And the torque acting on the ring gear shaft 32a via. Expression (1) for obtaining the target rotational speed Nm1 * of the motor MG1 can be easily derived by using the rotational speed relationship in this alignment chart. Expression (2) is a relational expression in feedback control for rotating the motor MG1 at the target rotational speed Nm1 *. In Expression (2), “k1” in the second term on the right side is a gain of the proportional term. “K2” in the third term on the right side is the gain of the integral term.

Nm1 * = Ne * ・ (1 + ρ) / ρ-Nm2 / (Gr ・ ρ) (1)
Tm1 * =-ρ / (1 + ρ) ・ Te * + k1 ・ (Nm1 * -Nm1) + k2 ・ ∫ (Nm1 * -Nm1) dt (2)

  If torque command Tm1 * for motor MG1 is set, input / output limits Win and Wout of battery 50, torque command Tm1 * for motor MG1 set in step S210, and current rotational speeds Nm1 and Nm2 of motors MG1 and MG2 Are used to calculate torque limits Tmin and Tmax as upper and lower limits of torque that may be output from the motor MG2 in accordance with the following equations (3) and (4) (step S220). Further, a temporary motor torque Tm2tmp which is a temporary value of torque to be output from the motor MG2 using the required torque Tr *, the torque command Tm1 *, the gear ratio ρ of the power distribution and integration mechanism 30 and the gear ratio Gr of the reduction gear 35. Is calculated according to the following equation (5) (step S230). Then, the torque command Tm2 * for the motor MG2 is set to a value obtained by limiting the temporary motor torque Tm2tmp with the torque limits Tmin and Tmax (step S240). Thus, by setting the torque command Tm2 * for the motor MG2, the torque output to the ring gear shaft 32a as the axle can be limited within the range of the input / output limits Win and Wout of the battery 50. Equation (5) can be easily derived from the alignment chart of FIG. If the target rotational speed Ne * and target torque Te * of the engine 22 and torque commands Tm1 * and Tm2 * for the motors MG1 and MG2 are thus set, the target rotational speed Ne * and the target torque Te * of the engine 22 are sent to the engine ECU 24. Then, torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 are transmitted to the motor ECU 40 (step S250), and the processes after step S100 are executed again. Receiving the torque commands Tm1 * and Tm2 *, the motor ECU 40 controls the switching elements of the inverters 41 and 42 so that the motor MG1 is driven according to the torque command Tm1 * and the motor MG2 is driven according to the torque command Tm2 *. Do. The engine ECU 24 that has received the target rotational speed Ne * and the target torque Te * is based on the target rotational speed Ne * and the target torque Te * in order to obtain the target rotational speed Ne * and the target torque Te *. The target intake air amount GA * is set, the target opening TH * of the throttle valve 123 is set based on the target intake air amount GA *, and the throttle valve 123 is opened based on the throttle position from the throttle valve position sensor 124. The throttle motor 125 is controlled so that the degree becomes the target opening TH *. Further, the engine ECU 24 executes fuel injection control, ignition timing control, valve timing control, exhaust gas recirculation control (hereinafter referred to as “EGR control”) and the like in addition to such throttle opening degree control.

Tmin = (Win-Tm1 * ・ Nm1) / Nm2 (3)
Tmax = (Wout-Tm1 * ・ Nm1) / Nm2 (4)
Tm2tmp = (Tr * + Tm1 * / ρ) / Gr (5)

  Here, the EGR control by the engine ECU 24 will be described. In the hybrid vehicle 20 of the embodiment, when the EGR flag Fegr is set to the value 1 by the above-described drive control routine and the operation mode of the hybrid vehicle 20 is set to the normal mode. In this case, the exhaust gas recirculation through the EGR valve 143 is executed. However, when the EGR flag Fegr is set to the value 0 by the drive control routine described above and the operation mode of the hybrid vehicle 20 is set to the power mode. The exhaust gas recirculation through the EGR valve 143 is not executed. That is, in the hybrid vehicle 20, the fuel consumption of the engine 22 can be further improved when the driving mode is set to the normal mode in which the fuel consumption is given priority over the torque output of the engine 22 according to the accelerator operation by the driver. As described above, exhaust gas recirculation through the EGR valve 143 is executed. Further, when the driving mode is set to a power mode in which the torque output is prioritized over the fuel consumption of the engine 22 according to the accelerator operation by the driver, the EGR valve is deliberately set so that the torque is output satisfactorily from the engine 22. The execution of exhaust gas recirculation through 143 is stopped. When executing exhaust gas recirculation via the EGR valve 143 under the normal mode, the CPU 24a of the engine ECU 24 recirculates to the intake system based on the rotational speed Ne of the engine 22 and the intake air amount GA. A target EGR amount Vegr * which is a target value of the EGR valve 143 and a command value degr (command duty ratio) for the EGR valve 143 corresponding to the target EGR amount Vegr * are set, and an actuator (for example, a step motor or the like) of the EGR valve 143 is not shown. ). When such EGR control is executed, the throttle opening correction is basically performed so that the throttle opening is increased as the target EGR amount Vegr * is increased in order to improve the fuel consumption by reducing the pumping loss. The ignition timing correction amount is set so that the ignition timing is advanced as the target EGR amount Vegr * is basically increased in order to suppress the combustion delay of the air-fuel mixture in the combustion chamber 120. The correction amount is used when throttle opening control and ignition timing control are separately executed.

  FIG. 7 is a flowchart showing an example of a fuel injection control routine that is repeatedly executed by the engine ECU 24 every predetermined time while the engine 22 is operating. The fuel injection control by the engine ECU 24 will be described with reference to FIG. 7. At the start of the routine of FIG. 7, the CPU 24a of the engine ECU 24 calculates the crankshaft 26 (engine engine) calculated based on the crank position from the crank position sensor 180. 22) the rotational speed Ne, the intake air amount GA from the air flow meter 183, a separately set target air-fuel ratio AF *, the cooling water temperature Tw from the water temperature sensor 181, the intake air temperature Tair from the intake air temperature sensor 184, the air-fuel ratio sensor Input processing of data necessary for control such as the air-fuel ratio AF from 186 and the value of the operation mode flag Fmod is executed (step S300).

  Next, it is determined whether or not the operation mode flag Fmod input in step S100 is 0 (step S310). If it is determined in step S310 that the operation mode flag Fmod is 0, that is, if the operation mode of the hybrid vehicle 20 is the normal mode, the rotation speed Ne input in step S300 and the injection for the normal mode are performed. The fuel injection end timing τe is set for each cylinder of the engine 22 using the end timing setting map (first injection timing setting constraint) (step S320). If it is determined in step S310 that the operation mode flag Fmod is a value 1, that is, if the operation mode of the hybrid vehicle 20 is the power mode, the rotation speed Ne and the power mode input in step S300 are used. The fuel injection end timing τe is set for each cylinder of the engine 22 using the injection end timing setting map (second injection timing setting constraint) (step S330). Here, the normal mode injection end time setting map and the power mode injection end time setting map are, as shown in FIG. 8, the rotational speed Ne of the crankshaft 26 and the fuel injection end time τe (upper It is determined in advance through experiments and analysis so as to define the relationship with the crank angle based on the dead center. In the hybrid vehicle 20 of the embodiment, the exhaust gas recirculation via the EGR valve 143 is used based on the fact that the fuel injection timing of the engine 22 does not necessarily match between the case where priority is given to fuel consumption and the case where priority is given to torque output. The normal mode injection end time setting map used under the normal mode is different from the power mode injection end time setting map used under the power mode that does not use exhaust gas recirculation. That is, the normal mode using exhaust gas recirculation is basically intended to improve fuel efficiency (energy efficiency), and therefore, in the normal mode, a vehicle equipped with only an engine as a source of driving power is used. Thus, it is not necessary to advance the fuel injection timing from the viewpoint of securing the engine torque. Further, under the power mode that does not use exhaust gas recirculation, the torque characteristics of the engine 22 can be made better by advancing the fuel injection timing as appropriate. For this reason, in the hybrid vehicle 20 according to the embodiment, the fuel injection end timing τe tends to be set to the advance side as compared with the injection timing setting map for the power mode compared with the injection end timing setting map for the normal mode. And a normal mode injection end time setting map for improving the fuel efficiency of the engine 22 by using exhaust gas recirculation, and a power mode end time for ensuring good torque output from the engine 22 without using exhaust gas recirculation The setting map is more appropriate for the main purpose of each operation mode. Further, in the hybrid vehicle 20 of the embodiment, the valve timing (opening / closing timing) of the intake valve 131 under the normal mode and the valve timing of the intake valve 131 under the power mode are the main purposes of each operation mode. Therefore, when creating the normal mode and power mode injection end timing setting maps, the valve timing of the intake valve 131 is also taken into consideration.

  If the fuel injection end timing τe of each cylinder is set in step S320 or S330, the cylinder is determined using the intake air amount GA, the target air-fuel ratio AF * and the basic injection time setting map (not shown) input in step S300. The basic injection time τp is set for each time (step S340). Further, an injection time correction process based on the set basic injection time τp and the cooling water temperature Tw, intake air temperature Tair, air-fuel ratio AF, etc., input in step S100 is executed to set the fuel injection time τ of each cylinder (step) S350). Then, after setting the fuel injection start timing τs of each cylinder based on the fuel injection end timing τe set in step S320 or S330 and the fuel injection time τ set in step S350 (step S360), for each cylinder Then, the fuel injection valve 127 is controlled so as to be opened for the fuel injection time τ from the fuel injection start timing τs (step S370), and the processing after step S300 is executed again.

  As described above, in the hybrid vehicle 20 of the embodiment, when the normal mode that prioritizes the fuel consumption (energy efficiency) according to the driver's accelerator operation is to be the operation mode, the exhaust gas recirculation via the EGR valve 143 is performed. The engine 22 is operated with the fuel injection timing at the fuel injection timing determined according to the normal mode injection end timing setting map, and the torque based on the required torque Tr * required for traveling is a ring gear shaft as an axle. The engine 22, the motor MG1, and the motor MG2 are controlled so as to be output to 32a (S140 to S160, S200 to S250 in FIG. 3, S320, S340 to S370 in FIG. 7). In addition, when the power mode that prioritizes torque output according to the driver's accelerator operation is to be the operation mode, the normal mode injection end time setting map without exhaust gas recirculation via the EGR valve 143; The engine 22 is operated with fuel injection at the fuel injection timing determined according to the injection end timing setting maps for different power modes, and torque based on the required torque Tr * is output to the ring gear shaft 32a as the axle. Thus, the engine 22, the motor MG1, and the motor MG2 are controlled (S170 to S190, S200 to S250 in FIG. 3, S330, S340 to S370 in FIG. 7).

  That is, in the hybrid vehicle 20, the driving mode can be switched between a normal mode in which fuel efficiency is prioritized over the torque output of the engine 22 and a power mode in which torque output is prioritized over the fuel consumption of the engine 22 according to the accelerator operation by the driver. In addition, the fuel efficiency of the engine 22 can be improved by using the exhaust gas recirculation under the normal mode, and the exhaust gas recirculation is not intentionally used under the power mode. The torque output can be secured better. Further, in the hybrid vehicle 20, the fuel injection timing of the engine 22 does not necessarily match between the case where priority is given to the fuel consumption of the engine 22 and the case where priority is given to torque output. The normal mode injection end time setting map used in the above is different from the power mode injection end time setting map used under the power mode that does not use exhaust gas recirculation. Accordingly, the normal mode injection end time setting map is adapted so that the fuel consumption of the engine 22 is further improved, and the power mode injection end time setting is ensured so that the torque output of the engine 22 is ensured. It is possible to adapt the map, and it is possible to further promote the merit by switching between the normal mode with priority on fuel consumption and the power mode with priority on torque and using exhaust gas recirculation. Therefore, in the hybrid vehicle 20 of the embodiment, the exhaust gas recirculation can be used more appropriately and the engine 22 can be more appropriately controlled to improve the energy efficiency while ensuring the power performance.

  In the hybrid vehicle 20, the normal mode using exhaust gas recirculation is basically intended to improve energy efficiency (fuel consumption). Therefore, only the engine 22 is used for driving power under the normal mode. It is not necessary to advance the fuel injection timing from the viewpoint of securing the torque of the engine 22 as in a vehicle provided as a generation source. Further, under the power mode that does not use exhaust gas recirculation, the torque characteristics of the engine 22 can be made better by advancing the fuel injection timing as appropriate. Therefore, if the fuel mode injection end timing setting map has a tendency to set the fuel injection timing to the advance side as compared with the normal mode injection end timing setting map, the engine can be used by exhaust gas recirculation. The normal mode injection end time setting map used under the normal mode for improving fuel efficiency and the power used under the power mode for ensuring the power performance of the engine 22 without using exhaust gas recirculation. The mode injection end timing setting map can be made more appropriate in accordance with the main purpose of each operation mode. If the normal mode and power mode injection end timing setting maps prescribe the relationship between the rotational speed Ne of the crankshaft 26 and the fuel injection end timing τe, normal mode and power mode injection The end timing setting map can be made more appropriate in accordance with the respective main purposes for which the fuel injection timing can be set so that the occurrence of knocking is suppressed.

  Further, in the hybrid vehicle 20 of the embodiment, when the normal mode should be the driving mode, the engine 22 corresponding to the required power P * based on the required torque Tr * is used using the fuel efficiency priority line that prioritizes the fuel efficiency of the engine 22. When the target rotational speed Ne * and the target torque Te *, which are target operating points, are set (steps S160 and S200 in FIG. 3) and the power mode should be the operating mode, the torque giving priority to the torque output of the engine 22 Using the priority operation line, the target rotational speed Ne * and the target torque Te * of the engine 22 corresponding to the required power P * based on the required torque Tr * are set (steps S190 and S200 in FIG. 3). That is, in the hybrid vehicle 20, by appropriately controlling the motors MG1 and MG2, the torque based on the required torque Tr * can be output to the ring gear shaft 32a as the axle while arbitrarily setting the operation point of the engine 22. Therefore, the fuel efficiency priority operation line used under the normal mode for improving the fuel efficiency of the engine 22 by using exhaust gas recirculation and the power mode for ensuring a good torque output of the engine 22 without using exhaust gas recirculation. If the torque priority operation line used in the engine is adapted to match the main purpose of the corresponding operation mode, the engine 22 is controlled and the power mode is controlled so that the fuel consumption is improved under the normal mode. Therefore, it is possible to control the engine 22 so as to ensure a good torque output.

  Further, in the hybrid vehicle 20 of the embodiment, it is determined that the normal mode should be the driving mode when the accelerator opening Acc indicating the accelerator operation amount by the driver is less than the mode determination threshold value Accref corresponding to the vehicle speed V, and the accelerator When the opening degree Acc is equal to or larger than the mode determination threshold value Accref, it is determined that the power mode should be the operation mode (steps S130, S140, S170). As a result, when it is assumed that the amount of accelerator operation by the driver (the amount by which the accelerator pedal 83 is depressed) is relatively small and the driver prioritizes (requests) improvement in energy efficiency (fuel consumption) over power performance. Can drive the hybrid vehicle 20 in the normal mode so that the energy efficiency (fuel consumption) is improved. Conversely, when it is assumed that the amount of accelerator operation by the driver is relatively large and the driver prioritizes (requests) the power performance over the improvement in energy efficiency (fuel consumption), the hybrid vehicle 20 is driven by the power performance. It is possible to drive under the power mode so as to ensure good.

  Next, a modification of the present invention will be described with reference to FIGS. 9 and 10. In addition, in a modification, the same reference number is attached | subjected to the element same as what was demonstrated in relation to the hybrid vehicle 20 of the said Example, and the overlapping description is abbreviate | omitted. FIG. 9 is a flowchart showing an example of a drive control routine according to a modified example. This drive control routine has a higher priority than fuel efficiency (energy efficiency) over torque output of the engine 22 and fuel efficiency improvement of the engine 22. The present invention is applied to a hybrid vehicle 20 having a power switch 88 (mode selection switch, see the two-dot chain line in FIG. 1) that allows the driver to select a power mode that prioritizes torque output. That is, the drive control routine of FIG. 9 is also executed by the hybrid ECU 70 every predetermined time (for example, every several msec) when the hybrid vehicle 20 is traveling with the operation of the engine 22.

  At the start of the drive control routine shown in FIG. 9, the CPU 72 of the hybrid ECU 70 determines the accelerator opening Acc from the accelerator pedal position sensor 84, the vehicle speed V from the vehicle speed sensor 87, the rotational speeds Nm1, Nm2 of the motors MG1, MG2, Input processing of data required for control such as the required discharge power Pb *, the input / output limits Win and Wout of the battery 50, and the value of the power switch flag Fpsw is executed (step S500). The power switch flag Fpsw is set to a value of 0 by the hybrid ECU 70 when the power switch 88 is turned off, that is, when the normal mode is selected as the driving mode of the hybrid vehicle 20 by the driver. When the switch 88 is turned on, that is, when the power mode is selected as the operation mode of the hybrid vehicle 20 by the driver, the hybrid ECU 70 sets the value 1 and holds it in a predetermined storage area.

  After the data input process of step S500, it is determined whether or not the input power switch flag Fpsw is a value 1 (step S510). If it is determined in step S510 that the power switch flag Fpsw has a value of 0, that is, if the driver has selected the fuel economy priority normal mode as the driving mode, the driving mode flag Fmod is set to a value of 0. (Step S520). Further, in order to improve the fuel consumption of the engine 22, the EGR flag Fegr is set to a value 1 so that exhaust gas recirculation through the EGR valve 143 is executed (step S530), and the accelerator opening Acc input in step S500. The execution accelerator opening Acc *, which is the accelerator opening for control, is set using the normal mode accelerator opening setting map as the first driving force setting constraint (step S540). On the other hand, if it is determined in step S510 that the power switch flag Fpsw has a value of 1, that is, if the driver has selected a torque-priority power mode as the operation mode, the operation mode flag Fmod is set. The value is set to 1 (step S550). Further, the EGR flag Fegr is set to 0 so that exhaust gas recirculation through the EGR valve 143 is not executed (step S560), and the accelerator opening Acc and the second driving force setting constraint input in step S500 are set. The accelerator opening Acc * for execution, which is the accelerator opening for control, is set using the accelerator opening setting map for the power mode (step S570).

  FIG. 10 illustrates an accelerator opening setting map for normal mode and an accelerator opening setting map for power mode. As shown in the figure, the accelerator opening setting map for the normal mode of the embodiment is such that the execution accelerator opening Acc * is linear with respect to the accelerator opening Acc in the range of 0 to 100%. It is created in advance and stored in the ROM 74. The normal mode accelerator opening setting map illustrated in FIG. 10 is created so that the accelerator opening Acc is set as the execution accelerator opening Acc * as it is. Further, the map for setting the accelerator opening for the power mode of the embodiment, as shown in FIG. 10, shows the accelerator opening Acc in an arbitrary low accelerator opening region in order to suppress the feeling of jumping out of the vehicle at a low vehicle speed. On the other hand, the same value as that set by the accelerator opening setting map for the normal mode is set as the accelerator opening Acc * for execution, and the accelerator opening Acc up to 100% other than the low accelerator opening range is set. On the other hand, in order to improve the response of the torque output to the accelerator operation, it is created so as to set a value larger than that set by the accelerator opening setting map for the normal mode as the execution accelerator opening Acc *. Stored in the ROM 74.

  If the execution accelerator opening Acc * is set in step S540 or S570, a request to be output to the ring gear shaft 32a as the axle based on the execution accelerator opening Acc * and the vehicle speed V input in step S100. After setting the torque Tr *, the required power P * required for the entire vehicle is set (step S580). In step S580, a value corresponding to the accelerator opening Acc * for execution and the vehicle speed V can be derived and set as the required torque Tr * from the required torque setting map shown in FIG. Further, the required power P * can be calculated in the same manner as in step S200 in FIG. Next, a temporary target rotational speed Nettmp and a temporary target torque Tentmp, which are temporary target operating points of the engine 22, are set based on the required power P * (step S590). In step S590, the temporary target rotational speed Nettmp and the temporary target torque Tempmp are obtained as the intersection of the fuel consumption priority operation line shown in FIG. 5 and the correlation curve indicating that the required power P * (Netmp × Ttmp) is constant, for example. Can do. In step S590, when the normal mode with priority on fuel consumption is selected as the driving mode by the driver, the temporary target rotational speed Netmp and the temporary target torque Tentmp of the engine 22 are calculated using the fuel efficiency priority operation line shown in FIG. When the torque priority power mode is selected as the operation mode by the driver, the temporary target rotational speed Netmp and the temporary target torque Tempmp of the engine 22 are set using the torque priority operation line shown in FIG. May be.

  After the process of step S590, it is determined whether or not the driving mode flag Fmod has a value of 1, that is, whether or not the power mode is selected by the driver (step S600), and the driving mode flag Fmod has a value of 0. When the normal mode is selected by the driver, the temporary target rotational speed Netmp is set as the target rotational speed Ne * of the engine 22 and the temporary target torque Tempmp is set as the target torque Te * of the engine 22 (step S610). On the other hand, when the driving mode flag Fmod is 1 and the power mode is selected by the driver, the lower limit of the rotational speed Ne of the engine 22 is set so that the engine 22 can output torque quickly. The engine lower limit rotation speed Nemin, which is a value, is set (step S620). In the embodiment, for example, the relationship between the vehicle speed V and the engine lower limit rotational speed Nemin is determined in advance so that the engine lower limit rotational speed Nemin increases as the vehicle speed V increases, and is stored in the ROM 74 as an engine lower limit rotational speed setting map (not shown). As the engine lower limit rotational speed Nemin, a value corresponding to the given vehicle speed V is derived and set from the map. If the engine lower limit rotational speed Nemin is set in this way, the larger of the temporary target rotational speed Netmp and the engine lower limit rotational speed Nemin is set as the target rotational speed Ne * of the engine 22, and the required power P set in step S160. The target torque Te * of the engine 22 is set by dividing * by the target rotational speed Ne * (step S630). Then, after the process of step S610 or S630, the processes of steps S640 to S680 similar to the processes of steps S210 to S250 of FIG. 3 are executed, and the processes after step S500 are executed again. Also in this modification, the motor ECU 40 that has received the torque commands Tm1 * and Tm2 * drives the inverter 41, so that the motor MG1 is driven according to the torque command Tm1 * and the motor MG2 is driven according to the torque command Tm2 *. Switching control of 42 switching elements is performed. The engine ECU 24 that has received the target rotational speed Ne * and the target torque Te * is based on the target rotational speed Ne * and the target torque Te * in order to obtain the target rotational speed Ne * and the target torque Te *. A target intake air amount GA * and a target opening TH * of the throttle valve 123 are set, and the throttle motor 125 is controlled so that the opening of the throttle valve 123 becomes the target opening TH *. Further, the engine ECU 24 performs fuel injection control (fuel injection control routine in FIG. 7), ignition timing control, valve timing control, exhaust gas recirculation control (hereinafter referred to as “EGR control”) and the like in addition to such throttle opening control. To do.

  Thus, when either the normal mode or the power mode can be selected as the operation mode by operating the power switch 88, the operation state of the power switch 88 is the driver's intention, that is, the energy efficiency (fuel consumption). Since it indicates which priority should be given to improvement and securing of power performance, in accordance with the driver's intention, the exhaust gas recirculation is more appropriately used and the engine 22 is more appropriately controlled to control the power of the vehicle. Energy efficiency can be improved while ensuring performance. Further, if the accelerator opening degree setting map for power mode has a tendency to set the accelerator opening degree Acc * for execution with respect to the same accelerator opening degree Acc larger than the accelerator opening degree setting map for normal mode, When the power mode is selected, the required torque Tr * for the same accelerator opening Acc can be set larger than when the normal mode is selected. Thereby, it is possible to improve the energy efficiency under the normal mode and to ensure good power performance under the power mode.

  In the hybrid vehicle 20 of the above embodiment, the ring gear shaft 32a as the axle and the motor MG2 are connected via the reduction gear 35 that reduces the rotational speed of the motor MG2 and transmits it to the ring gear shaft 32a. Instead of the gear 35, for example, a transmission that changes the rotational speed of the motor MG2 having two or three shift stages of Hi and Lo and transmits it to the ring gear shaft 32a may be employed. Moreover, although the hybrid vehicle 20 of an Example outputs the motive power of motor MG2 to the axle connected to the ring gear shaft 32a, the application object of this invention is not restricted to this. That is, the present invention is different from the axle (the axle to which the wheels 39a and 39b are connected) that is connected to the ring gear shaft 32a as in the hybrid vehicle 20A according to the modification shown in FIG. The present invention may be applied to the one that outputs to the wheels 39c and 39d in FIG. Furthermore, the hybrid vehicle 20 according to the embodiment outputs the power of the engine 22 to the ring gear shaft 32a as an axle connected to the wheels 39a and 39b via the power distribution and integration mechanism 30. Is not limited to this. That is, the present invention provides an inner rotor 232 connected to the crankshaft of the engine 22 and an outer rotor connected to an axle that outputs power to the wheels 39a and 39b, like a hybrid vehicle 20B according to the modification shown in FIG. 234, and may be applied to a motor including a counter-rotor motor 230 that transmits a part of the power of the engine 22 to the axle and converts the remaining power into electric power.

  Here, the correspondence between the main elements of the above embodiments and modifications and the main elements of the invention described in the column of means for solving the problems will be described. That is, in the above-described embodiment, the EGR pipe 142 connected to the exhaust pipe and recirculates the exhaust gas to the surge tank and the recirculation amount of the exhaust gas recirculated from the exhaust system to the intake system provided in the middle of the EGR pipe 142 The engine 22 having the EGR valve 143 for adjusting the power corresponds to the “internal combustion engine”, the combination of the motor MG1 and the power distribution / integration mechanism 30 and the rotor motor 230 correspond to “power / power input / output means”. Motor MG2 capable of inputting / outputting power to / from ring gear shaft 32a corresponds to “electric motor”, and battery 50 capable of exchanging electric power with motors MG1 and MG2 corresponds to “power storage means”. In step S110 of FIG. 3 or FIG. The hybrid ECU 70 that executes the processes of S520 to S580 corresponds to the “required driving force setting means”, and the step S120 in FIG. The hybrid ECU 70 that executes the process of S130 and the process of step S510 of FIG. 9 corresponds to the “mode determining means”, and the hybrid ECU 70, the motor ECU 40 that executes the drive control routine of FIG. 3 or FIG. A combination with the control ECU and the engine ECU 24 that executes EGR control corresponds to “control means”. Further, the power switch 88 corresponds to a “mode selection switch”, the motor MG1 corresponds to a “motor for power generation”, and the power distribution and integration mechanism 30 corresponds to “a three-axis power input / output unit”.

  However, the “internal combustion engine” is not limited to the engine 22 that outputs power by receiving a hydrocarbon-based fuel such as gasoline or light oil, and may be of any other type such as a hydrogen engine. "Power / power input / output means" is connected to the engine shaft of the internal combustion engine and a predetermined axle that transmits power to the drive wheels, and inputs / outputs power to / from the engine shaft and axle along with input / output of power and power. As long as it does, the combination of the motor MG1 and the power distribution and integration mechanism 30 or any type other than the anti-rotor motor 230 may be used. “Electric motor” and “electric generator motor” are not limited to synchronous generator motors such as motors MG1 and MG2, and may be of any other type such as an induction motor. The “storage means” is not limited to the secondary battery such as the battery 50, and may be any other type such as a capacitor as long as it can exchange electric power with the motor. The “required driving force setting means” is not limited to the one that sets the required torque as the required driving force based on the accelerator opening and the vehicle speed, but, for example, the one that sets the required driving force based only on the accelerator opening. Any other format may be used. The “control means” may be of any type other than the combination of the hybrid ECU 70, the engine ECU 24, and the motor ECU 40. In any case, the correspondence between the main elements of the embodiments and the modified examples and the main elements of the invention described in the column of means for solving the problems is the same as the means for the embodiments to solve the problems. Since this is an example for specifically explaining the best mode for carrying out the invention described in the column, the elements of the invention described in the column for means for solving the problems are not limited. In other words, the examples are merely specific examples of the invention described in the column of means for solving the problem, and the interpretation of the invention described in the column of means for solving the problem is described in the description of that column. Should be done on the basis.

  The embodiments of the present invention have been described above using the embodiments. However, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the present invention. Needless to say.

  The present invention can be used in the manufacturing industry of hybrid vehicles.

It is a schematic block diagram of the hybrid vehicle 20 of an Example. 2 is a schematic configuration diagram of an internal combustion engine device 21. FIG. It is a flowchart which shows an example of the drive control routine performed by hybrid ECU70 of an Example. It is explanatory drawing which shows an example of the map for request | requirement torque setting. It is explanatory drawing which illustrates the correlation curve which shows that a fuel consumption priority operation line, a torque priority operation line, and required power P * become fixed. FIG. 4 is an explanatory diagram illustrating a collinear diagram illustrating a dynamic relationship between the rotational speed and torque of a rotating element in the power distribution and integration mechanism 30 when the hybrid vehicle 20 is running with the engine 22 operated. It is a flowchart which shows an example of a fuel-injection control routine. It is explanatory drawing which illustrates the injection end time setting map for normal modes, and the injection end time setting map for power modes. It is a flowchart which shows an example of the drive control routine which concerns on a deformation | transformation. It is explanatory drawing which illustrates the map for accelerator opening setting for normal modes, and the map for accelerator opening setting for power modes. It is a schematic block diagram of the hybrid vehicle 20A which concerns on a modification. FIG. 12 is a schematic configuration diagram of a hybrid vehicle 20B according to another modification.

Explanation of symbols

  20, 20A, 20B Hybrid vehicle, 21 Internal combustion engine device, 22 Engine, 24 Electronic control unit for engine (engine ECU), 24a, 72 CPU, 24b, 74 ROM, 24c, 76 RAM, 26 Crankshaft, 28 Damper, 30 Power distribution and integration mechanism, 31 sun gear, 32 ring gear, 32a ring gear shaft, 33 pinion gear, 34 carrier, 35 reduction gear, 37 gear mechanism, 38 differential gear, 39a-39d wheels, 40 motor electronic control unit (motor ECU), 41 , 42 Inverter, 43, 44 Rotation position detection sensor, 50 battery, 51 Temperature sensor, 52 Electronic control unit for battery (battery ECU), 54 Power line, 70 Electronic control unit for hybrid (hive ECU), 80 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 86 brake pedal stroke sensor, 87 vehicle speed sensor, 88 power switch, 120 combustion chamber, 121 piston, 122 air cleaner, 123 throttle valve, 124 throttle valve position sensor, 125 throttle motor, 126 intake pipe, 127 fuel injection valve, 128 ignition plug, 129 ignition coil, 130 valve operating mechanism, 131 intake valve, 132 exhaust valve, 133 Cam position sensor, 140 Exhaust manifold, 141 Purification device, 142 EGR pipe, 143 EGR valve, 144 Temperature sensor, 180 Crank position sensor, 181 Water temperature sensor, 182 In-cylinder pressure sensor, 183 Air flow meter, 184 Intake temperature sensor, 185 Intake pressure sensor, 186 Air-fuel ratio sensor, 230 rotor motor, 232 inner rotor, 234 outer rotor, MG1, MG2 motor

Claims (10)

An internal combustion engine having exhaust gas recirculation means for recirculating exhaust gas from the exhaust system to the intake system;
Power power input / output means connected to the engine shaft of the internal combustion engine and a predetermined axle for transmitting power to the drive wheels and for inputting / outputting power to / from the engine shaft and the axle with input / output of power and power When,
An electric motor capable of outputting power to the axle or another axle different from the axle;
A power storage means capable of exchanging power with the power input / output means and the electric motor;
A required driving force setting means for setting a required driving force required for traveling;
Mode determining means for determining which one of the first mode prioritizing energy efficiency and the second mode prioritizing power performance based on a predetermined operation by the driver should be the operation mode;
When the mode determination means determines that the first mode should be the operation mode, the exhaust gas recirculation by the exhaust gas recirculation means and the fuel injection at the fuel injection timing determined according to the first injection timing setting constraint The internal combustion engine is operated, and the internal combustion engine, the power power input / output means, and the electric motor are controlled so that power based on the set required driving force is obtained, and the mode determination means When it is determined that the second mode should be the operation mode, the fuel injection is determined according to a second injection timing setting constraint different from the first injection timing setting constraint without the exhaust gas recirculation. The internal combustion engine is operated with fuel injection at a timing, and power based on the set required driving force is obtained. And control means for controlling said electric motor and the electric power-mechanical power input output means;
A hybrid car with The hybrid vehicle according to claim 1,
The second injection timing setting constraint is a hybrid vehicle having a tendency to set the fuel injection timing to an advance side as compared with the first injection timing setting constraint. The hybrid vehicle according to claim 1 or 2,
The first and second injection timing setting constraints are a hybrid vehicle that is a constraint that defines the relationship between the rotational speed of the engine shaft and the fuel injection end timing of the internal combustion engine. The hybrid vehicle according to any one of claims 1 to 3,
When the mode determination unit determines that the first mode should be the operation mode, the control unit uses the first operation point setting constraint that prioritizes the fuel consumption of the internal combustion engine. The target operating point of the internal combustion engine corresponding to the requested driving force is set, and the setting is performed with the exhaust gas recirculation and the fuel injection at the fuel injection timing determined according to the first injection timing setting constraint. The internal combustion engine is operated at a target operating point, and the internal combustion engine, the power power input / output means and the electric motor are controlled so that power based on the set required driving force is obtained, and the mode determination means When it is determined that the second mode should be the operation mode, a second operation point setting constraint that gives priority to the power performance of the internal combustion engine is set. And setting a target operating point of the internal combustion engine corresponding to the set required driving force, and accompanied by fuel injection at a fuel injection timing determined according to the second injection timing setting constraint without accompanying exhaust gas recirculation. The hybrid that controls the internal combustion engine, the power power input / output means, and the electric motor so that the internal combustion engine is operated at the set target operating point and power based on the set required driving force is obtained. Car. The hybrid vehicle according to any one of claims 1 to 4,
The predetermined operation is an operation of depressing an accelerator pedal,
The mode determination means determines that the first mode should be the driving mode when the accelerator operation amount by the driver is less than a predetermined threshold, and the accelerator operation amount by the driver is greater than or equal to the threshold. A hybrid vehicle that determines that the second mode should be the driving mode. The hybrid vehicle according to any one of claims 1 to 3,
The required driving force setting means determines the amount of accelerator operation by the driver using the first driving force setting constraint when the mode determination means determines that the first mode should be the driving mode. When the corresponding required driving force is set, and the mode determining means determines that the second mode should be the operating mode, the same accelerator as compared with the first driving force setting constraint A hybrid vehicle that sets the required driving force corresponding to an accelerator operation amount by a driver using a second driving force setting constraint that tends to set the required driving force with respect to an operation amount large. The hybrid vehicle according to claim 6,
When the mode determining unit determines that the first mode should be the operation mode, the control unit determines the set required driving force and the operating point at which the internal combustion engine is efficiently operated. When the operating point of the internal combustion engine is set using the operating point setting restriction to be defined and the second mode is determined to be the operating mode by the mode determining means, the set operating point is set. The operating point of the internal combustion engine is set using the required driving force and the operating point setting constraint or another operating point setting constraint different from the operating point setting constraint and the lower limit rotational speed of the internal combustion engine determined according to the vehicle speed A hybrid car. In the hybrid vehicle according to any one of claims 1 to 3, 6 and 7,
The predetermined operation is an operation of a mode selection switch that enables selection between the first mode and the second mode;
The mode determination means is a hybrid vehicle that determines which of the first and second modes should be set as a driving mode based on an operation state of the mode selection switch by a driver. The hybrid vehicle according to any one of claims 1 to 8, wherein the power power input / output means includes a generator motor capable of inputting / outputting power, the axle, the engine shaft of the internal combustion engine, and the generator motor. And a three-axis power input / output means for inputting / outputting power to / from the remaining shafts based on power input / output to / from any two of these three axes. . An internal combustion engine having exhaust gas recirculation means for recirculating exhaust gas from the exhaust system to the intake system, and a predetermined axle that transmits power to the engine shaft and drive wheels of the internal combustion engine are connected to the power and power. Power power input / output means for inputting / outputting power to / from the engine shaft and the axle with output, an electric motor capable of outputting power to the axle or another axle different from the axle, and the power power input / output means And a control method of a hybrid vehicle comprising a power storage means capable of exchanging electric power with the electric motor,
(A) determining which of the first mode that prioritizes energy efficiency and the second mode that prioritizes power performance based on a predetermined operation by the driver should be the operation mode;
(B) When it is determined in step (a) that the first mode should be the operation mode, the exhaust gas recirculation by the exhaust gas recirculation means and the fuel injection timing determined according to the first injection timing setting constraint Controlling the internal combustion engine, the power power input / output means, and the electric motor so that the internal combustion engine is operated with fuel injection at the same time and power based on the set required driving force is obtained. When it is determined in (a) that the second mode should be the operation mode, a second injection timing setting constraint different from the first injection timing setting constraint without accompanying the exhaust gas recirculation. The internal combustion engine and the internal combustion engine are operated so as to be operated with fuel injection at a fuel injection timing determined according to And controlling the a force-mechanical power input output means and said motor,
Control method of hybrid vehicle including

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