JP5972704B2 - Control device and control method for hybrid vehicle - Google Patents

Description

  The present invention relates to a control device and a control method for a hybrid vehicle driven using an internal combustion engine and an electric motor.

  A hybrid vehicle is a vehicle provided with two different power sources, an engine (internal combustion engine) and a motor (electric motor). Such a hybrid vehicle includes an exhaust gas recirculation device that recirculates exhaust gas to an intake passage, and changes the target engine speed and target torque depending on whether the exhaust gas recirculation device is activated or not ( For example, see Patent Document 1). In addition, there is a type that controls the closing timing of the intake valve that sucks air into the engine and the amount of exhaust gas recirculated by the exhaust gas recirculation device according to the charge amount of the battery that supplies power to the motor (for example, , See Patent Document 2).

JP 2010-241273 A JP 2010-95084 A

  The target torque of the engine while the hybrid vehicle is running is set to a torque at which the net fuel consumption rate (Brake Specific Fuel Consumption: hereinafter referred to as BSFC) is an optimum value. BSFC is the fuel consumed in one cycle of the engine (fuel injection amount) divided by the engine output (net horsepower).

  However, this BSFC characteristic changes due to environmental changes (for example, changes in engine intake air temperature, humidity, torque estimation error, etc.), aging of vehicles, variations in individual engines, and the like. In this case, even if various kinds of control are performed so as to optimize the BSFC, the BSFC characteristics actually change, so that the BSFC is not actually in an optimal state, resulting in deterioration of fuel efficiency. There is a fear. On the other hand, in the hybrid vehicles described in Patent Documents 1 and 2, the deterioration of fuel efficiency based on the change in the BSFC characteristics is not taken into consideration.

  The present invention has been made in view of the above problems, and even when the BSFC characteristics change due to aging of the vehicle, variation of individual engines, etc., the BSFC can be optimized, the fuel efficiency is deteriorated, etc. An object of the present invention is to provide a control device for a hybrid vehicle and a control method thereof.

  In order to solve the above problems, the present invention is configured as follows.

The control device for a hybrid vehicle according to the present invention includes an internal combustion engine (2) as a power source of the vehicle, an ignition device (71) capable of changing the ignition timing of the internal combustion engine (2), and the power of the internal combustion engine (2). A part of the exhaust gas discharged into the exhaust passage (60) of the internal combustion engine (2). 2) The exhaust gas recirculation device (76) for recirculation to the intake passage (59) of the internal combustion engine (2), the ignition device (71), the electric motor (3), and the exhaust gas circulation device (76) are controlled. A control unit (10) for controlling the hybrid vehicle, wherein the control unit (10) is configured to charge the battery (30) while the vehicle is running when the intake passage of the internal combustion engine (2) is charged. brake specific fuel consumption on the basis of the shaft output of the intake air amount and the engine to (2) Estimating the rate, in the best torque estimated net fuel consumption rate becomes an optimum value is set as a torque of the internal combustion engine (2), and sets the optimum torque, the intake air quantity, an ignition device (71 ) and the retard amount from the optimum ignition timing according to calculated an exhaust recirculation rate calculated from the amount of exhaust gas recirculated to the intake passage and the intake air amount by the exhaust recirculation device (76), a slow The angular amount is set to a value smaller than a predetermined threshold value, and the exhaust gas recirculation rate is set to a value larger than the predetermined threshold value .

  According to the hybrid vehicle control device of the present invention, the net fuel consumption rate is estimated based on the intake air amount of the internal combustion engine, the retard amount from the optimal ignition timing by the ignition device, and the exhaust gas recirculation rate of the internal combustion engine. By setting the optimal torque at which the estimated net fuel consumption rate is optimal as the torque of the internal combustion engine, the characteristics of the net fuel consumption rate (BSFC) change due to aging of the vehicle, individual variations of the internal combustion engine, etc. Even in such a case, it is possible to perform control so as to optimize the BSFC. Accordingly, it is possible to avoid a deterioration in fuel efficiency based on a change in BSFC characteristics.

  In the hybrid vehicle control device, the control unit (10) optimizes the intake air amount in order to enable control to optimize the BSFC even when the characteristics of the BSFC change as described above. As the maximum intake air amount that can be taken based on the retard amount from the ignition timing and the exhaust gas recirculation rate, an optimal value of the net fuel consumption rate may be estimated. It is also preferable to estimate an optimal value of the net fuel consumption rate at which at least the exhaust gas recirculation rate is larger than a predetermined threshold value. Alternatively, it is preferable to estimate an optimal value of the net fuel consumption rate at which the amount of retardation from the optimal ignition timing by the ignition device (71) is smaller than a predetermined threshold value.

  In the above hybrid vehicle control device, the control unit (10), when the optimum torque is smaller than the vehicle drive request torque, determines the difference between the drive request torque and the optimum torque by the torque of the electric motor (3). It is good to assist. According to this configuration, the vehicle can be driven by efficiently using the driving force of the electric motor.

  In the hybrid vehicle control device, the control unit (10) generates power by the electric motor (3) with the difference between the optimal torque and the required drive torque when the optimal torque is greater than the required drive torque of the vehicle. It is preferable to charge the battery (30) with the electric power generated by the power generation.

  The hybrid vehicle control device includes an atmospheric pressure sensor (37) for detecting or estimating the atmospheric pressure, and the control unit (10) determines the amount of retardation based on the value of the atmospheric pressure sensor (37). The exhaust gas recirculation rate may be corrected. According to this configuration, even when the characteristics of the exhaust gas recirculation rate change according to the atmospheric pressure, it is possible to perform control so as to optimize the BSFC.

  In the hybrid vehicle control device according to the present invention, the internal combustion engine (2) as a power source of the vehicle, the ignition device (71) capable of changing the ignition timing of the internal combustion engine (2), and the internal combustion engine (2) An electric motor (3) for assisting the power of the engine, a battery (30) for transferring electric power to and from the electric motor (3), and a part of the exhaust gas discharged into the exhaust passage of the internal combustion engine (2). ) In the intake passage (59), a stepped transmission (4) for stepwise shifting the power output from the internal combustion engine (2), and an internal combustion engine ( 2) A control device for a hybrid vehicle comprising: an ignition device (76); an electric motor (3); an exhaust circulation device (76); and a control unit (10) for controlling each part including the transmission (4). The control unit (10) is configured to suck into the intake passage (59) of the internal combustion engine (2). Exhaust gas recirculation calculated from the air volume, the retarded amount from the optimum ignition timing by the ignition device (71), and the exhaust gas amount and the intake air amount recirculated to the intake passage (59) by the exhaust gas recirculation device (76). The net fuel consumption rate is estimated based on the circulation rate, the optimum torque at which the estimated net fuel consumption rate becomes the optimum value is set as the torque of the internal combustion engine, and the control unit (10) determines that the optimum torque is the vehicle drive request. When the torque is smaller than the torque, the difference between the drive request torque and the optimum torque is assisted by the torque of the electric motor (3). Alternatively, when the optimum torque is greater than the drive request torque of the vehicle, the control unit (10) performs power generation by the electric motor (3) with a difference between the optimum torque and the drive request torque, and stores the electric power generated by the electric power storage device ( 30) is charged.

  According to this configuration, even when the characteristic of the net fuel consumption rate (BSFC) changes due to the aging of the vehicle, the individual variation of the internal combustion engine, etc., it is possible to perform control so as to optimize the BSFC. In addition, the torque corresponding to the required driving force of the vehicle is achieved while the internal combustion engine is operated so as to optimize the BSFC by assisting the torque of the difference between the required driving torque of the vehicle and the optimal torque by the torque of the electric motor. Can be improved to improve the running performance of the vehicle. In addition, by generating electric power with the electric motor with the difference between the optimum torque and the required driving torque of the vehicle, and charging the electricity with the electric power generated by the electric power generation, the surplus torque for the required driving force of the vehicle can be used effectively. The remaining capacity of the battery can be secured. Therefore, the energy efficiency of the vehicle can be improved.

The hybrid vehicle control method according to the present invention includes an internal combustion engine (2) as a power source of the vehicle, an ignition device (76) capable of changing the ignition timing of the internal combustion engine (2), and the internal combustion engine (2). A part of the exhaust gas discharged to the exhaust passage (60) of the internal combustion engine (2). An exhaust gas recirculation device (76) for recirculation to the intake passage (59) of the engine (2), a stepped transmission (4) for stepwise shifting the power output from the internal combustion engine (2), A control method of a hybrid vehicle comprising: an internal combustion engine (2), an ignition device (71), an electric motor (3), an exhaust gas circulation device (76), and a control unit (10) that controls each part including a transmission (4). a is, the control unit (10) is charged to the capacitor (30) during running of the vehicle When performing, on the basis of the shaft output of the intake air amount to the intake passage of the internal combustion engine (2) and the internal combustion engine (2) estimating the net fuel consumption rate, the estimated net fuel consumption rate becomes an optimum value When setting the optimum torque as the torque of the internal combustion engine (2) and setting the optimum torque, the retard amount from the optimum ignition timing by the ignition device (71) and the exhaust gas recirculation device ( 76), the exhaust gas recirculation rate calculated from the exhaust gas amount recirculated to the intake passage and the intake air amount is calculated, the retard amount becomes a value smaller than a predetermined threshold value, and the exhaust gas recirculation rate is predetermined. It is characterized in that the value is larger than the threshold value .

According to the hybrid vehicle control method of the present invention, the net fuel consumption rate is estimated based on the intake air amount of the internal combustion engine, the retard amount from the optimal ignition timing by the ignition device, and the exhaust gas recirculation rate of the internal combustion engine. By setting the optimal torque at which the estimated net fuel consumption rate is optimal as the torque of the internal combustion engine, the characteristics of the net fuel consumption rate (BSFC) change due to aging of the vehicle, individual variations of the internal combustion engine, etc. Even in such a case, it is possible to perform control to optimize the BSFC. Accordingly, it is possible to avoid a deterioration in fuel efficiency based on a change in BSFC characteristics.
In addition, the code | symbol in said parenthesis shows the code | symbol of the component in embodiment mentioned later as an example of this invention.

  According to the control apparatus and the control method for a hybrid vehicle according to the present invention, it is possible to perform control so as to optimize the BSFC even when the BSFC characteristic changes. Accordingly, it is possible to avoid a deterioration in fuel efficiency based on a change in BSFC characteristics.

It is a block diagram which shows the structure of the control apparatus of the hybrid vehicle which concerns on embodiment of this invention. It is sectional drawing which shows schematic structure of the engine which concerns on embodiment of this invention, and its intake / exhaust system. It is a figure which shows the relationship between an engine torque and BSFC. It is a figure which shows the relationship between the ignition timing (retard amount) according to an EGR rate and engine torque, and the relationship between the ignition timing (retard amount) according to an EGR rate and BSFC. The relationship between the ignition timing (retard amount) according to the charging efficiency (ηc) of the intake air amount and the engine torque, and the ignition timing (retard amount) according to the charging efficiency (ηc) of the intake air amount and the BSFC It is a figure which shows a relationship. It is a figure which shows the relationship between BSFC, an EGR rate, the ignition timing of a spark plug, and differential pressure | voltage. It is a figure which shows the relationship between charging efficiency ((eta) c) and ignition timing, the relationship between ignition timing and combustion torque, and the relationship between an EGR rate and combustion torque / GAIR. It is a figure which shows the relationship between a torque and ignition timing, and the relationship between a torque and an EGR rate. 3 is a flowchart for illustrating the operation of the hybrid vehicle control apparatus according to the first embodiment of the present invention. It is a figure which shows an IG table and an EGR table. It is a flowchart for demonstrating operation | movement of the control apparatus of the hybrid vehicle by Embodiment 2 of this invention. It is a figure which shows an IG table and an EGR table. It is a flowchart for demonstrating operation | movement of the control apparatus of the hybrid vehicle by Embodiment 3 of this invention. It is a flowchart for demonstrating operation | movement of the control apparatus of the hybrid vehicle by Embodiment 4 of this invention.

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

Embodiment 1 FIG.
FIG. 1 is a block diagram showing a configuration of a control apparatus for a hybrid vehicle according to an embodiment of the present invention. As shown in FIG. 1, the vehicle 1 according to this embodiment is a hybrid vehicle equipped with an engine 2 and an electric motor 3 as drive sources, and further includes an inverter 20 for controlling the electric motor 3, a battery 30, a transmission (transmission) 4, a differential mechanism 5, left and right drive shafts 6R and 6L, and left and right drive wheels WR and WL. Here, the electric motor 3 is a motor and includes a motor generator, and the battery 30 is a capacitor and includes a capacitor. The internal combustion engine 2 is an engine, and includes a diesel engine, a turbo engine, and the like. The rotational driving force of the internal combustion engine (hereinafter referred to as “engine”) 2 and the electric motor (hereinafter referred to as “motor”) 3 is driven to the left and right via the transmission 4, the differential mechanism 5 and the drive shafts 6R and 6L. It is transmitted to the wheels WR and WL.

  In addition, the vehicle 1 includes an electronic control unit (for controlling the engine 2 (including an exhaust gas recirculation device 76 described later; see FIG. 2)), the motor 3, the transmission 4, the differential mechanism 5, the inverter 20, and the battery 30. ECU: Electronic Control Unit (ECU) 10 is provided. The electronic control unit 10 is configured not only as a single unit, but also, for example, an engine ECU for controlling the engine 2, a motor generator ECU for controlling the motor 3 and the inverter 20, and a battery 30 for controlling the battery 30. The battery ECU may include a plurality of ECUs such as an AT-ECU for controlling the transmission 4. The electronic control unit 10 according to this embodiment controls the engine 2 and also controls the motor 3, the battery 30, and the transmission 4.

  The electronic control unit 10 performs control so that the motor alone travels (EV travel) using only the motor 3 as a power source according to various operating conditions, or performs the engine alone travel using only the engine 2 as a power source. Control is performed so as to perform cooperative traveling (HEV traveling) in which both the engine 2 and the motor 3 are used as power sources. Further, the electronic control unit 10 performs control for setting a target torque of the engine 2 to be described later and other control necessary for various operations according to various control parameters.

  In addition, signals from various sensors 31 to 41 are input to the electronic control unit 10 as control parameters. Specifically, the electronic control unit 10 includes an accelerator pedal opening degree from an accelerator pedal sensor 31 that detects an accelerator pedal depression amount, a brake pedal opening degree from a brake pedal sensor 32 that detects a brake pedal depression amount, The shift position from the shift position sensor 33 that detects the gear stage (shift stage), the motor rotation speed from the rotation speed sensor 34 that detects the rotation speed of the motor 3, and the inclination from the inclination angle sensor 35 that detects the inclination of the vehicle 1 A signal indicating a corner is input. Further, the electronic control unit 10 includes a measured temperature from a water temperature sensor 36 that measures the temperature of cooling water that cools the engine 2, a measured pressure from an atmospheric pressure sensor 37 that measures atmospheric pressure, and an intake air temperature that measures the intake air temperature. A signal indicating the measured temperature from the sensor 38 is input. The electronic control unit 10 receives a signal indicating a knocking occurrence state from a knocking sensor 39 that detects knocking of the engine 2 (abnormal combustion state of the engine 2). The electronic control unit 10 also measures the crank angle from the crank angle sensor 40 that detects the rotation angle of the crankshaft 55 and the air-fuel ratio sensor 41 that measures the air-fuel ratio (mixing ratio of air and gasoline as fuel). A signal indicating a value is input.

  The engine 2 is an internal combustion engine that generates driving force for running the vehicle 1 by mixing fuel with air and burning it. The motor 3 functions as a motor that generates a driving force for running the vehicle 1 using the electric energy of the battery 30 when the engine 2 and the motor 3 are collaboratively run or when the EV 3 is driven only by the motor 3. In addition, when the vehicle 1 is decelerated, it functions as a generator that generates electric power by regeneration of the motor 3. During regeneration of the motor 3, the battery 30 is charged with electric power (regenerative energy) generated by the motor 3.

  FIG. 2 is a cross-sectional view showing a schematic configuration of the engine and its intake and exhaust system according to the embodiment of the present invention. The engine 2 has four cylinders (cylinders) 52. A piston 53 is slidably provided in the cylinder 52. The piston 53 is connected to the crankshaft 55 via a connecting rod 54, and the crankshaft 55 rotates as the piston 53 reciprocates.

  In the cylinder 52, a combustion chamber 56 is formed between the upper end of the piston 53 and a cylinder head (not shown). An intake port 57 and an exhaust port 58 are connected to the combustion chamber 56. The intake port 57 and the exhaust port 58 are connected to an intake passage 59 and an exhaust passage 60, respectively.

  An intake side timing pulley 61 and an exhaust side timing pulley 62 are drivingly connected to the crankshaft 55 via a belt (not shown). An intake camshaft 64 is attached to the intake side timing pulley 61 via a variable valve timing mechanism 70 described later. An exhaust camshaft 65 that rotates integrally with the exhaust side timing pulley 62 is attached to the exhaust side timing pulley 62.

  The intake valve 66 and the exhaust valve 67 open and close the intake port 57 and the exhaust port 58, respectively. That is, the intake valve 66 and the exhaust valve 67 are opened and closed by cams provided on the intake camshaft 64 and the exhaust camshaft 65, respectively. Further, when the crankshaft 55 rotates twice, the intake side timing pulley 61 and the exhaust side timing pulley 62 each rotate once. Accordingly, the intake valve 66 and the exhaust valve 67 are opened and closed at a predetermined timing in synchronization with the rotation of the crankshaft 55.

  Further, as described above, the intake side timing pulley 61 is provided with a variable valve timing mechanism (hereinafter referred to as a VVT (Variable Valve Timing) mechanism) 70. The VVT mechanism 70 changes the relative rotational phase between the intake side timing pulley 61 and the intake camshaft 64 by the action of hydraulic pressure, so that the cam provided on the intake camshaft 64 is relative to the crankshaft 55. Change the rotation phase. The opening / closing timing of the intake valve 66 can be changed to the advance side or the retard side by changing the relative phase.

  Each cylinder 52 is provided with a spark plug 71 for spark-igniting the air-fuel mixture in the combustion chamber 56, and the intake port 57 is provided with a fuel injection valve 72 for injecting fuel into the intake port 57. Yes. The intake passage 59 is provided with a throttle valve 74 that adjusts the flow rate of fresh air (intake air amount) flowing through the intake passage 59. Further, the exhaust passage 60 is provided with an exhaust purification device (for example, a three-way catalyst) 75 for purifying harmful substances contained in the exhaust gas.

  In this embodiment, the engine 2 is provided with an exhaust gas recirculation device (EGR device) 76 that recirculates a part of the exhaust gas discharged to the exhaust passage 60 to the intake passage 59. The EGR device 76 includes an EGR passage 77, an EGR valve 78, and an EGR cooler 79. The EGR passage 77 is a pipe that connects the exhaust passage 60 downstream of the exhaust purification device 75 and the intake passage 59 downstream of the throttle valve 74. The EGR cooler 79 is provided in the EGR passage 77, and cools the exhaust gas flowing through the EGR passage 77.

  In the EGR device 76 of this embodiment, an EGR valve 78 is provided in the EGR passage 77, and the flow rate of the recirculation gas (exhaust gas) flowing through the EGR passage 77 by changing the opening degree thereof. Can be adjusted. In this embodiment, the exhaust gas in the EGR passage 77 is drawn toward the intake passage 59 by the pressure difference between the pressure in the intake passage 59 and the atmospheric pressure. Therefore, as the opening of the throttle valve 74 increases and the amount of intake air flowing through the intake passage 59 increases, the differential pressure decreases and the flow rate of exhaust gas entering the intake passage 59 decreases. Thus, in this embodiment, the flow rate of the exhaust gas recirculated changes with the opening degree of the throttle valve 74 together with the opening degree of the EGR valve 78.

  Hereinafter, the recirculation of a part of the exhaust gas flowing through the exhaust passage 60 as the exhaust gas through the EGR passage 77 to the intake passage 59 may be simply referred to as EGR. When EGR is performed in this way, the exhaust gas is introduced into the cylinder 52 while being mixed with fresh air flowing through the intake passage 59. The exhaust gas contains an inert gas component that does not burn itself and has a high heat capacity, such as water and carbon dioxide. Therefore, when the exhaust gas is contained in the air-fuel mixture, the combustion temperature of the air-fuel mixture is lowered, and the amount of nitrogen oxide (NOx) generated is reduced. Moreover, fuel consumption can be reduced by performing EGR.

  In this embodiment, a value obtained by dividing the exhaust gas amount recirculated by the EGR device 76 into the intake passage 59 by the sum of the exhaust gas amount and the intake air amount (exhaust gas amount / (exhaust gas amount + intake air amount). )) Is called the exhaust gas recirculation rate (hereinafter referred to as "EGR rate") (unit:%).

  Next, the relationship between the BSFC, the EGR rate, and the retard amount (retard angle correction amount) of the ignition timing of the spark plug 71 will be described.

  FIG. 3 is a diagram showing the relationship between the torque of the engine 2 and the BSFC. As shown in FIG. 3, the friction (friction) is improved and the combustion is improved as the value of the torque of the engine 2 (shown as “axis TRQ” in FIG. 3; the unit is Nm) increases. As a result, the value of BSFC gradually decreases. In addition, BSFC has shown that efficiency (fuel efficiency) is so good that a value is small.

  As shown in FIG. 3, as the torque value of the engine 2 further increases, the BSFC rapidly rises at a certain value (the value indicated by ◎ in FIG. 3). Such a phenomenon is that knocking occurs when the torque is increased too much, and control is performed to retard (slow) the ignition timing of the spark plug 71 in order to reduce knocking, and the throttle valve 74 is used to increase the torque. When the opening degree of the valve is increased, the differential pressure decreases and the EGR rate decreases.

  The value at which the BSFC in FIG. 3 has decreased most (the value marked with に お け る in FIG. 3) is called the BSFC bottom, and the torque at the BSFC bottom is called BSFC bottom torque. As described above, the target torque of the engine 2 during traveling of the vehicle 1 is set to a torque (BFSC bottom torque) at which the BSFC becomes an optimum value (BSFC bottom). The electronic control unit 10 includes a BSFC characteristic model obtained in advance from various characteristics of the engine 2. Then, the electronic control unit 10 estimates the BSFC bottom from the BSFC characteristic model, and sets the BSFC bottom torque (or the torque immediately before the BSFC bottom) as the target torque. However, as described above, the characteristic model of the BSFC changes due to environmental changes, aging of vehicles, engine individual variations, and the like. For this reason, the BSFC bottom estimated from the BSFC characteristic model in advance deviates from the actual BSFC bottom. In this case, as shown in FIG. 3, if the torque at the time when the BSFC suddenly increases is set as the target torque, the fuel efficiency is deteriorated. Therefore, in this embodiment, the electronic control unit 10 is configured so that each engine 2 in various environments is based on parameters (intake air amount, ignition timing of the spark plug 71, and EGR rate) that are correlated with the BSFC. Estimate the BSFC bottom.

  FIG. 4 is a diagram showing the relationship between the ignition timing (retard amount) according to the EGR rate and the engine torque, and the relationship between the ignition timing (retard amount) according to the EGR rate and the BSFC. 4A shows the relationship between the ignition timing (retard amount) according to the EGR rate and the torque of the engine 2, and FIG. 4B shows the ignition timing (retard amount) according to the EGR rate and the BSFC. Shows the relationship. The rotational speed of the engine 2 is constant (for example, 1500 rpm), and the charging efficiency (an index representing the absolute amount of fresh air (intake air amount) contributing to combustion in the engine 2) is a constant value (for example, 58%). Yes.

  In FIG. 4A, the horizontal axis (IGLOG) indicates the ignition timing, and the unit is deg. When it goes from 0 to the left, it indicates that the ignition timing is retarded (becomes late, retards), and when it goes from 0 to the right, it indicates that the ignition timing is advanced (becomes earlier). In FIG. 4A, the vertical axis (TRQ) indicates torque, and the torque increases as it goes upward. The unit is Nm. In FIG. 4A, the symbol ◎ indicates the optimum ignition timing (MBT) at which the torque is maximum. As shown in FIG. 4A, the torque decreases as the ignition timing is retarded. Further, the higher the EGR rate, the greater the torque. Further, the lower the EGR rate, the smaller the amount of torque decrease even if the ignition timing retardation amount increases.

  In FIG. 4B, the horizontal axis (IGLOG) indicates the ignition timing, and the unit is deg. As in FIG. 4A, the ignition timing is retarded (delayed, retarded) when progressing from 0 to the left, and the ignition timing is advanced (accelerated) when proceeding from 0 to the right. It is shown that. In FIG. 4B, the vertical axis indicates BSFC, and the efficiency is improved as it goes down. The unit is g / kWh. In FIG. 4B, the symbol ◎ indicates the optimal ignition timing (MBT) at which BSFC is minimized. As shown in FIG. 4B, the BSFC increases as the ignition timing is retarded. Also, the higher the EGR rate, the smaller the BSFC.

  In this way, the characteristics of the BSFC change as the EGR rate changes. That is, the EGR rate is a parameter that correlates with the characteristics of the BSFC.

  FIG. 5 shows the relationship between the ignition timing (retard amount) according to the charging efficiency (ηc) of the intake air amount and the torque of the engine 2, and the ignition timing (retard amount) according to the charging efficiency (ηc) of the intake air amount. ) And BSFC. 5A shows the relationship between the ignition timing (retard amount) corresponding to the intake air amount charging efficiency (ηc) and the torque of the engine 2, and FIG. 5B shows the intake air amount charging efficiency ( The relationship between ignition timing (retard amount) according to ηc) and BSFC is shown. The rotational speed of the engine 2 is constant (for example, 1500 rpm), and the EGR rate is constant (for example, 0%).

  In FIG. 5A, the horizontal axis (IGLOG) indicates the ignition timing, and the unit is deg. When it goes from 0 to the left, it indicates that the ignition timing is retarded (becomes late, retards), and when it goes from 0 to the right, it indicates that the ignition timing is advanced (becomes earlier). In FIG. 5A, the vertical axis (TRQ) indicates torque, and the torque increases as it goes upward. The unit is Nm. In FIG. 5A, the symbol ◎ indicates the optimum ignition timing (MBT) at which the torque is maximum. As shown in FIG. 5A, the torque decreases as the ignition timing is retarded. Further, the higher the filling efficiency, the greater the torque.

  In FIG. 5B, the horizontal axis (IGLOG) indicates the ignition timing, and the unit is deg. As in FIG. 5A, the ignition timing is retarded (delayed, retarded) when progressing from 0 to the left, and the ignition timing is advanced (accelerated) when proceeding from 0 to the right. It is shown that. In FIG. 5B, the vertical axis indicates BSFC, and the efficiency is improved as it goes down. The unit is g / kWh. In FIG. 5B, the symbol ◎ indicates the optimum ignition timing (MBT) at which BSFC is minimized. As shown in FIG. 5B, the BSFC increases as the ignition timing is retarded. Also, the higher the filling efficiency, the smaller the BSFC.

  In this way, the characteristics of the BSFC change as the charging efficiency (that is, the intake air amount corresponding to the charging efficiency) changes. That is, the intake air amount is a parameter that correlates with the characteristics of the BSFC.

  FIG. 6 is a diagram showing the relationship between the BSFC, the EGR rate, the ignition timing of the spark plug 71, and the differential pressure. In FIG. 6, the horizontal axis (PBGA) indicates differential pressure, and the unit is mmHg. It shows that the differential pressure increases when proceeding from 0 to the left. Although the horizontal axis in FIG. 6 is the differential pressure, the differential pressure has the same tendency as the charging efficiency and the intake air amount. That is, the characteristic change (curve) due to the change in the differential pressure and the characteristic change due to the change in the charging efficiency or the intake air amount have the same tendency. In FIG. 6, the left side of the vertical axis shows BSFC, and the efficiency decreases as it goes down. In FIG. 6, the right side of the vertical axis shows the EGR rate (TOTAL GR) and the ignition timing (IGLOG).

  As shown in FIG. 6, the ignition timing retard amount (IGLOG) is a substantially constant value even when the differential pressure decreases, but suddenly retards when the differential pressure decreases below a predetermined value. The retard amount increases. As for the EGR rate, the EGR rate is a substantially constant value even when the differential pressure is reduced. However, when the differential pressure is reduced below a predetermined value, the EGR rate is rapidly lowered. As described above, when the differential pressure decreases below a predetermined value, the retard amount increases rapidly and the EGR rate decreases rapidly. Therefore, the BSFC increases rapidly when the differential pressure decreases below a predetermined value.

  Thus, the characteristics of the BSFC change as the intake air amount (differential pressure), EGR rate, and ignition timing (retard amount) change. That is, the intake air amount, the EGR rate, and the ignition timing are parameters that correlate with the characteristics of the BSFC.

  In this embodiment, the intake air amount is as much as possible (specifically, as will be described later, the EGR rate does not become smaller than the predetermined threshold value, and the retard amount from the optimal ignition timing (MBT) is The BSFC is estimated as a large amount (maximum intake air amount) as much as possible within a range not exceeding a predetermined threshold. On the other hand, regarding the EGR rate and the ignition timing (retard amount), these values are monitored as parameters, and the BSFC is estimated based on these parameters.

  Next, a method for calculating (estimating) the BSFC from various characteristics of the engine 2 will be described.

  FIG. 7 is a graph showing the relationship between charging efficiency (ηc) and ignition timing, the relationship between ignition timing and combustion torque, and the relationship between EGR rate and combustion torque / GAIR. 7A shows the relationship between charging efficiency (ηc) and ignition timing, FIG. 7B shows the relationship between ignition timing and combustion torque, and FIG. 7C shows the EGR rate and combustion torque. The relationship of / GAIR is shown.

  The electronic control unit 10 measures the atmospheric pressure by the atmospheric pressure sensor 37, searches an intake air amount map (not shown) corresponding to the measured value, and calculates an intake air amount (GAIR). Note that the maximum intake air amount corresponding to the measured value of the atmospheric pressure is sucked into the intake passage 59 of the engine 2. The electronic control unit 10 calculates the charging efficiency (ηc) from the intake air amount (GAIR). Then, the electronic control unit 10 searches the IGLOG map shown in FIG. 7A according to the charging efficiency, and calculates the IGLOG (ignition timing retardation amount) corresponding to the charging efficiency. Note that IGCR in FIG. 7A is a retarded amount (retard amount) from the optimal ignition timing (MBT) accompanying the occurrence of cracking.

  Further, the electronic control unit 10 searches the combustion TRQ map shown in FIG. 7B according to the IGLOG, and calculates the combustion TRQ (combustion torque) corresponding to the IGLOG. Further, the electronic control unit 10 calculates the combustion TRQ / GAIR from the combustion TRQ. Then, the electronic control unit 10 searches the EGR map shown in FIG. 7C according to the combustion TRQ / GAIR, and calculates the EGR rate corresponding to the combustion TRQ / GAIR.

  BSFC is calculated from the following equation (1).

BSFC (g / kwh) = GFUEL (g) / ENG axis output (kwh)
= {GAIR (g / sec) x (1 / air-fuel ratio)} / {NE (rpm) x axis TRQ (Nm) x (2π / 60) / 3600/1000} (1)

  Here, GFUEL is the fuel amount, GAIR is the intake air amount, NE is the engine speed, and the shaft TRQ is the shaft torque.

  As described above, the intake air amount (GAIR) is calculated from the measured value of the atmospheric pressure sensor 37. The air / fuel ratio is measured by the air / fuel ratio sensor 41. Further, the rotational speed (NE) of the engine 2 is measured by the rotational speed sensor 34.

  The axis TRQ (torque) is calculated from the following equation (2).

  Axis TRQ (Nm) = (GAIR (g / sec) × KGATRQ × KIGTRQDN) −ENG friction torque (2)

  Here, GAIR (g / sec) × KGATRQ × KIGTRQDN is the combustion TRQ (combustion torque). The electronic control unit 10 searches a KIGRQDN map (not shown) according to the ignition timing retardation amount IGLOG and the engine speed NE, and shows a torque reduction coefficient indicating a reduction rate of the engine output torque due to the ignition timing retardation amount. KIGTRQDN is calculated. The KIGTRQDN map is set so that the torque reduction coefficient KIGTRQDN decreases as the retard amount IGLOG increases. The torque reduction coefficient KIGTRQDN takes a value greater than “0” and less than or equal to “1”. Further, the electronic control unit 10 calculates the conversion coefficient KGATRQ from the combustion TRQ / (GAIR × KIGTRQDN) derived from the equation (2).

  From the above, the ignition timing retardation amount (IGLOG), the EGR rate, and the shaft torque are calculated. Further, by calculating the shaft torque, BFSC is calculated based on the equation (1).

  FIG. 8 is a diagram showing the relationship between the torque of the engine 2 and the ignition timing, and the relationship between the torque and the EGR rate. In the figure, the change in BSFC with respect to the torque of the engine 2 is also shown. From the torque (shaft torque) calculated as described above and the retard amount of the ignition timing, the relationship (characteristic) between the torque and the ignition timing shown in FIG. 8A is obtained, and the torque calculated as described above. From the (shaft torque) and the EGR rate, the relationship (characteristic) between the torque and the EGR rate shown in FIG. Further, as shown in FIG. 8 (A), in order to avoid the occurrence of knocking of the engine 2, the retard amount (retard amount) from the optimal ignition timing (MBT) increases rapidly, so that the BSFC increases rapidly. It gets worse (gets bigger). Further, as shown in FIG. 8B, the differential pressure for introduction decreases, and the EGR rate rapidly decreases, and the BSFC rapidly deteriorates (increases).

  Next, the operation of the hybrid vehicle control device will be described.

  FIG. 9 is a flowchart for illustrating the operation of the hybrid vehicle control apparatus according to the first embodiment of the present invention. First, the electronic control unit 10 recognizes the rotational speed of the engine 2 based on a signal from the rotational speed sensor 34, and searches a map corresponding to the rotational speed, whereby the target charging torque (vehicle 1) corresponding to the rotational speed is searched. The target torque of the engine 2 when the battery 30 is charged during the travel is calculated (step S1).

  Next, the electronic control unit 10 recognizes the coolant temperature for cooling the engine 2 based on the signal from the water temperature sensor 36, recognizes the atmospheric pressure based on the signal from the atmospheric pressure sensor 37, and detects the intake air temperature sensor. The temperature of intake air (intake air) is recognized based on the signal from 38. The electronic control unit 10 then displays an IG table corresponding to the recognized water temperature, atmospheric pressure, and intake air temperature (a characteristic map indicating the relationship (characteristic) between the torque and the retard amount of the ignition timing as shown in FIG. 8A). Table), EGR table (table of characteristic map showing relationship (characteristic) between torque and EGR rate as shown in FIG. 8B), KIGTRQDN table (table of KIGTRQDN map), and KGATRQ table (table of KGATRQ map) Is calculated (step S2). Here, as described above, since the intake air amount changes according to the measurement value (atmospheric pressure value) of the atmospheric pressure sensor 37, the IG table and the EGR table corresponding to the measurement value of the atmospheric pressure sensor 37 are selected. (That is, the retardation amount and the EGR rate corresponding to the measured value of the atmospheric pressure sensor 37 are corrected). Similarly, since the intake air amount changes according to the measured value (water temperature temperature) of the water temperature sensor 36, the IG table and the EGR table corresponding to the measured value of the water temperature sensor 36 are selected (that is, the water temperature sensor 36). It is corrected to the retard amount and EGR rate corresponding to the measured value). Further, since the intake air amount changes in accordance with the measured value of the intake air temperature sensor 38 (intake air temperature value), the IG table and EGR table corresponding to the measured value of the intake air temperature sensor 38 are selected (that is, the intake air temperature). The amount of retardation and the EGR rate corresponding to the measured value of the sensor 38 are corrected).

  Further, the electronic control unit 10 calculates a torque (shaft torque) of the engine 2 and calculates a BSFC, thereby calculating a BSFC characteristic table (a table of characteristic maps indicating the relationship (characteristic) between torque and BSFC). (Step S3).

  Then, the electronic control unit 10 calculates a retard amount (IG) of the ignition timing at the target charging torque based on the IG table, and whether or not the calculated retard amount is smaller than a predetermined threshold value. That is, it is determined whether or not the retard amount from the optimum ignition timing at the target charging torque is larger than the retard amount from the optimum ignition timing to a predetermined threshold value (step S4). As a result, when the retardation amount D1 at the target charging torque T1 is smaller than the predetermined threshold DA as in the retardation amount D1 at the target charging torque T1 shown in FIG. 10A (Yes in step S4), the step The process proceeds to S5. On the other hand, when the retardation amount D2 at the target charging torque T2 is larger than the predetermined threshold DA as in the retardation amount D2 at the target charging torque T2 shown in FIG. 10 (A) (No in step S4), The process proceeds to step S8.

  In step S5, the electronic control unit 10 calculates an EGR rate at the target charging torque based on the EGR table, and determines whether or not the calculated EGR rate is smaller than a predetermined threshold value (that is, the target charging torque). It is determined whether or not the amount of decrease from the set EGR rate is larger than the amount of decrease from the set EGR rate to a predetermined threshold value (step S5). As a result, when the EGR rate E1 at the target charging torque T1 is smaller than the predetermined threshold EA (Yes in step S5) as in the EGR rate E1 at the target charging torque T1 shown in FIG. Transition to processing. On the other hand, when the EGR rate E2 at the target charging torque T2 is larger than the predetermined threshold EA as in the EGR rate E2 at the target charging torque T2 shown in FIG. 10B (No at step S5), step S8. Move on to processing.

  In step S6, the electronic control unit 10 acquires the BSFC bottom torque from the BSFC characteristic table calculated in step S3. Then, the electronic control unit 10 sets (changes) this BSFC bottom torque to the target charging torque (step S7). Specifically, as shown in FIG. 10A, when the retardation amount D1 at the target charging torque T1 is smaller than the threshold value DA, the torque (BSFC bottom) corresponding to the threshold value DA is used instead of the target charging torque T1. Torque) is set (changed) as the target charging torque. As shown in FIG. 10B, when the EGR rate E1 at the target charging torque T1 is smaller than the threshold EA, the torque (BSFC bottom torque) corresponding to the threshold EA is used instead of the target charging torque T1. Set (change) as charging torque. On the other hand, in the case of No in step S4 and No in step S5, the target charging torque calculated in step S1 is set as it is. Specifically, as shown in FIG. 10A, when the retardation amount D2 at the target charging torque T2 is larger than the threshold value DA, the target charging torque T2 is set as it is. Further, as shown in FIG. 10B, the target charging torque T2 is set as it is even when the retardation amount E2 in the target charging torque T2 is larger than the threshold value EA.

  The electronic control unit 10 outputs the target charging torque set in step S7 (step S8). That is, the engine 2 is controlled to be driven with the target charging torque. Here, as shown in FIGS. 10A and 10B, when the target charging torque is larger than the ENG torque (the required driving torque of the engine 2), the surplus torque (the torque that is the difference between the target charging torque and the ENG torque). ) Becomes a charging torque, and the battery 30 is charged with electric power (electric energy) generated by driving the motor 3 with the charging torque.

  As described above, according to the first embodiment, the BSFC is estimated based on the intake air amount of the engine 2, the retard amount of the ignition timing by the ignition device 71, and the EGR rate of the engine 2, and the estimated BSFC By setting the optimal torque that gives the optimal value as the torque of the engine 2, even if the characteristics of the BSFC change due to aging of the vehicle, individual variations of the engine 2, etc., control is performed to optimize the BSFC. It becomes possible. Moreover, since it is comprised so that the battery 30 may be charged with the surplus torque with respect to the target torque set based on the BSFC characteristic, charging efficiency can be improved. Note that the processing in steps S6 and S7 is executed on the condition of Yes in step S4 and Yes in step S5. However, the processing in steps S6 and S7 is executed only on the condition of Yes in step S4. You may make it perform the process of step S6, S7 only on condition of Yes.

Embodiment 2. FIG.
In the first embodiment, the target torque (target charging torque) of the engine 2 when the battery 30 is charged while the vehicle 1 is traveling is calculated, and the calculated target torque is set. On the other hand, in the second embodiment, the target torque of the engine 2 when assisting the power of the engine 2 by the power of the motor 3 while the vehicle 1 is traveling (that is, the vehicle is assisted by the motor 3). Target torque of the engine when running 1:
This target torque is sometimes referred to as assist torque. ) And the calculated target torque is set.

  FIG. 11 is a flowchart for explaining the operation of the hybrid vehicle control apparatus according to the second embodiment of the present invention. FIG. 12 is a diagram showing an IG table and an EGR table. First, the electronic control unit 10 recognizes the rotational speed of the engine 2 based on a signal from the rotational speed sensor 34, and calculates an assist torque corresponding to the rotational speed by searching a map corresponding to the rotational speed ( Step S11). Thereafter, the processes of steps S12 and S13 are executed. The processes in steps S12 and S13 are the same as the processes in steps S2 and S3 in FIG.

  Next, the electronic control unit 10 calculates a retard amount (IG) of the ignition timing in the assist torque based on the IG table, and whether or not the calculated retard amount is smaller than a predetermined threshold value. That is, it is determined whether or not the retard amount from the optimum ignition timing in the assist torque is larger than the retard amount from the optimum ignition timing to a predetermined threshold value (step S14). As a result, when the retard amount D3 in the assist torque T3 is smaller than the predetermined threshold DA as in the retard amount D3 in the assist torque T3 shown in FIG. 12A (Yes in step S14), the process proceeds to step S15. Transition to processing. On the other hand, when the delay amount in the assist torque is larger than the predetermined threshold DA (such as the delay amount D4 in the assist torque T4 shown in FIG. 12A) (No in step S14), the processing in step S18 is performed. Transition.

  In step S15, the electronic control unit 10 calculates the EGR rate in the assist torque based on the EGR table, and determines whether or not the calculated EGR rate is smaller than a predetermined threshold value (that is, the setting in the assist torque). It is determined whether or not the amount of decrease from the EGR rate is greater than the amount of decrease from the set EGR rate to a predetermined threshold value (step S15). As a result, when the EGR rate E3 in the assist torque T3 is smaller than the predetermined threshold EA as in the EGR rate E3 in the assist torque T3 shown in FIG. 12B (Yes in step S15), the process in step S16 is performed. Transition. On the other hand, when the EGR rate E4 in the assist torque T4 is larger than the threshold EA as in the EGR rate E4 in the assist torque T4 (No in step S15), the process proceeds to step S18.

  In step S16, the electronic control unit 10 acquires the BSFC bottom torque from the BSFC characteristic table calculated in step S13 (step S16). Then, the electronic control unit 10 sets (changes) the BSFC bottom torque to the assist torque (step S17). Specifically, as shown in FIG. 12A, when the retardation amount D3 in the assist torque T3 is smaller than the threshold value DA, torque corresponding to the threshold value DA (BSFC bottom torque) instead of the assist torque T3. Is set (changed) as assist torque. As shown in FIG. 10B, when the EGR rate E3 in the assist torque T3 is smaller than the threshold EA, torque corresponding to the threshold EA (BSFC bottom torque) is used as the assist torque instead of the assist torque T3. Set (change). On the other hand, in the case of No in step S14 and No in step S15, the assist torque calculated in step S11 is set as it is. Specifically, as shown in FIG. 12A, when the retard amount D4 in the assist torque T4 is larger than the threshold value DA, the assist torque T4 is set as it is. Also, as shown in FIG. 12B, the assist torque T4 is set as it is even when the retardation amount E4 in the assist torque T4 is larger than the threshold value EA.

  The electronic control unit 10 determines the assist torque set in step S17 (step S18). Then, the electronic control unit 10 determines whether or not the determined assist torque is smaller than the drive request torque (step S19). As a result, when the assist torque is smaller than the drive request torque (Yes in step S19), the ENG torque is output as the assist torque, and the difference between the drive request torque and the assist torque (ENG torque) is set as the torque of the motor 3. To assist (step S20). On the other hand, when the assist torque is greater than the drive request torque (No in step S19), the ENG torque is output as the drive request torque (step S21). In this case, the assist of the power of the engine 2 by the motor 3 is not executed.

  As described above, according to the second embodiment, as in the first embodiment, it is possible to avoid a deterioration in fuel efficiency based on a change in BSFC characteristics. In addition, when the target torque set based on the BSFC characteristic is insufficient for the drive request torque, the motor 3 is configured to assist the power of the engine 2. 1 run can be performed. The processing in steps S16 and S17 is executed on the condition of Yes in step S14 and Yes in step S15. However, the processing in steps S16 and S17 is executed only on the condition of Yes in step S14. You may make it perform the process of step S16, S17 on condition only of Yes.

Embodiment 3 FIG.
In the hybrid vehicle including the engine 2, the motor 3, and the battery 30, when the remaining capacity SOC (State of Charge) of the battery 30 is small, the battery 30 is controlled to be charged immediately, and the remaining capacity of the battery 30 is large. In this case, it is preferable to perform control so that the battery 30 is charged more slowly than when the remaining capacity SOC is small. Therefore, in the third embodiment, the electronic control unit 10 determines whether or not the value of the remaining capacity SOC of the battery 30 exceeds a predetermined threshold before performing the processes of steps S1 to S8 in FIG. (Step S31) When the threshold value is not exceeded, a target charging torque map A for calculating a smaller target charging torque is set as a target charging torque map used when calculating the target charging torque in Step S1 ( Step S32) When the threshold value is exceeded, a target charging torque map B for calculating a larger target charging torque is set as the target charging torque map (step S33). Subsequent processing (steps S1 to S8) is the same as the processing described in FIG.

  As described above, according to the third embodiment, the charging speed of battery 30 can be changed according to the remaining capacity SOC of battery 30.

Embodiment 4 FIG.
In general, in the engine 2, knocking is likely to occur due to the influence of humidity or aging, or the crankshaft is rattled and pulse fluctuations are likely to occur. In this case, there is a possibility that the retard amount (retard amount) of the ignition timing is increased based on the occurrence of knocking, or the EGR rate is decreased based on pulse fluctuation. Therefore, in the fourth embodiment, when knocking or pulse fluctuation is detected by a sensor, control for switching a map (table) used when calculating a target torque is executed.

  FIG. 14 is a flowchart for explaining the operation of the hybrid vehicle control apparatus according to the fourth embodiment of the present invention. First, the electronic control unit 10 determines whether knocking has occurred by the knocking sensor 39 (step S41). If it is determined that knocking has not occurred (No in step S41), the electronic control unit 10 calculates BSFC characteristics based on the base map (the base table calculated in steps S2 and S3 in FIG. 9) ( Step S42). On the other hand, if it is determined that knocking has occurred (Yes in step S41), the electronic control unit 10 moves the ignition timing to the retard side (retard side) from the base map (increases the retard amount). Switched to another map (step S43), and BSFC characteristics are calculated based on the switched map (step S44).

  Next, based on the crank angle detected by the crank angle sensor 40, the electronic control unit 10 determines whether or not a decrease in the EGR rate due to pulse fluctuation has occurred (step S45). As a result, if it is determined that a decrease in the EGR rate due to pulse fluctuation has not occurred (No in step S45), the electronic control unit 10 sets the base EGR rate (the EGR rate calculated in steps S2 and S3 in FIG. 9) to Based on this, the BSFC characteristic is calculated (step S46). On the other hand, when it is determined that a decrease in the EGR rate due to the pulse fluctuation has occurred (Yes in step S45), the electronic control unit 10 decreases the base EGR rate by learning (step S47), and the reduced EGR rate. The BSFC characteristic is calculated based on (Step S48).

  As described above, according to the fourth embodiment, an appropriate BSFC can be calculated in accordance with a change in BSFC characteristics based on deterioration of the engine 2 or the like.

  The above-described embodiments are preferred examples of the present invention, but the present invention is not limited to these, and various modifications and changes can be made without departing from the scope of the present invention. is there.

  For example, the transmission (transmission) 4 is preferably a stepped transmission that changes the power output from the engine 2 in stages, but is not limited to such a transmission. In addition, each sensor is not limited to the case where the quantity is measured / detected, but may be configured to estimate the quantity from the measured / detected value. For example, the atmospheric pressure sensor measures atmospheric pressure, but may be configured to measure altitude and estimate atmospheric pressure from the measured altitude.

1 Vehicle 2 Engine 3 Motor (electric motor)
4 Transmission (transmission)
10 Electronic control unit (ECU)
30 Battery 34 Speed sensor 36 Water temperature sensor 37 Atmospheric pressure sensor 38 Intake air temperature sensor 39 Knock sensor 40 Crank angle sensor 41 Air-fuel ratio sensor 76 Exhaust gas recirculation device (EGR device)

Claims (7)

An internal combustion engine as a power source for the vehicle;
An ignition device capable of changing the ignition timing of the internal combustion engine;
An electric motor for assisting the power of the internal combustion engine;
A battery for transferring power to and from the motor;
An exhaust gas recirculation device for recirculating a part of the exhaust gas discharged to the exhaust passage of the internal combustion engine to the intake passage of the internal combustion engine;
A control unit for a hybrid vehicle comprising: a control unit that controls each part including the internal combustion engine, the ignition device, the electric motor, and an exhaust gas circulation device;
The controller is
When charging the battery while the vehicle is running,
A net fuel consumption rate is estimated based on an intake air amount to the intake passage of the internal combustion engine and a shaft output of the internal combustion engine, and an optimal torque at which the estimated net fuel consumption rate becomes an optimal value is calculated. Set as torque, and
When setting the optimum torque,
From the intake air quantity, the ignition device optimally and the retard amount from the ignition timing, the exhaust gas recirculation apparatus by recirculated by the exhaust gas recirculation is calculated from the exhaust gas quantity and said intake air quantity to the intake passage by Rate and
The control apparatus for a hybrid vehicle, wherein the retard amount is a value smaller than a predetermined threshold value, and the exhaust gas recirculation rate is a value larger than a predetermined threshold value . Wherein, as the maximum intake air quantity that can be taken on the basis of the retard amount and the said exhaust gas recirculation rate from the intake air amount the optimum ignition timing, estimates the optimum value of the net fuel consumption rate The control apparatus of the hybrid vehicle of Claim 1. Wherein, when the optimum torque is less than the drive required torque of the vehicle, according to the torque difference between the optimum torque and the drive torque demand to claim 1 or claim 2, assisted by the torque of the electric motor Control device for hybrid vehicle. When the optimal torque is greater than the drive request torque of the vehicle, the control unit generates power by the motor with a difference between the optimal torque and the drive request torque, and charges the battery with electric power generated by the power generation The control apparatus of the hybrid vehicle in any one of Claims 1-3 . A temperature sensor for detecting or estimating the temperature of the internal combustion engine;
The hybrid vehicle control device according to any one of claims 1 to 4 , wherein the control unit corrects the retardation amount and the exhaust gas recirculation rate based on a value of the temperature sensor. It has an atmospheric pressure sensor that detects or estimates atmospheric pressure,
The control device for a hybrid vehicle according to any one of claims 1 to 5 , wherein the control unit corrects the retardation amount and the exhaust gas recirculation rate based on a value of the atmospheric pressure sensor. An internal combustion engine as a power source for the vehicle;
An ignition device capable of changing the ignition timing of the internal combustion engine;
An electric motor for assisting the power of the internal combustion engine;
A battery for transferring power to and from the motor;
An exhaust gas recirculation device for recirculating a part of the exhaust gas discharged to the exhaust passage of the internal combustion engine to the intake passage of the internal combustion engine;
A stepped transmission that changes the power output from the internal combustion engine in stages;
A control method for a hybrid vehicle comprising: the internal combustion engine, the ignition device, the electric motor , an exhaust gas circulation device, and a control unit that controls each part including the transmission,
The controller is
When charging the battery while the vehicle is running,
A net fuel consumption rate is estimated based on an intake air amount to the intake passage of the internal combustion engine and a shaft output of the internal combustion engine, and an optimal torque at which the estimated net fuel consumption rate becomes an optimal value is calculated. Set as torque, and
When setting the optimum torque,
From the intake air amount, the ignition device the optimum and the retard amount from the ignition timing, the exhaust gas recirculation apparatus by recirculated by the exhaust gas recirculation is calculated from the exhaust gas quantity and said intake air quantity to the intake passage by Rate and
The hybrid vehicle control method, wherein the retardation amount is a value smaller than a predetermined threshold value, and the exhaust gas recirculation rate is a value larger than a predetermined threshold value .

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