JP6291780B2 - Hybrid vehicle and control method thereof - Google Patents

Description

  The present invention relates to a hybrid vehicle capable of driving an internal combustion engine with a motor generator and a control method therefor, and more specifically, a minimum when fuel is injected in a minute amount such as pilot injection or after injection in fuel injection control of the internal combustion engine. The present invention relates to a hybrid vehicle in which an injection amount control value can be set and updated in accordance with a machine difference and aging of an internal combustion engine, and a control method thereof.

  In a traveling form of a hybrid vehicle equipped with both an internal combustion engine (engine) and a motor generator (traveling motor) and using both of them as a power source for traveling, a form of traveling using only the internal combustion engine as a drive source (hereinafter referred to as a driving source) , Referred to as engine independent travel), traveling with only a motor generator as a drive source (hereinafter referred to as motor traveling alone), traveling with both an internal combustion engine and a motor generator as drive sources (hereinafter referred to as motor assisted travel) And so on).

  In the operation of the internal combustion engine, in order to obtain good combustion in the cylinder, pilot injection is performed before the main injection, or after injection and post injection are performed after the main injection. In this pilot injection, after injection, and the like, control for injecting a minute amount of fuel is performed.

  However, because there is a machine difference that varies from machine to machine in the fuel injection nozzle, even if a control value for injecting the same minute quantity is output to the fuel injection nozzle side, it is not always possible to inject with the same injection quantity. Depending on the case, even if the same control value is output, depending on the fuel injection nozzle, there may be a case where a small amount of fuel is injected and a case where the fuel is not injected.

  Therefore, the setting of the minimum injection amount control value (minimum value of the injection amount control value) for this small amount of fuel injection is relatively large so that a small amount of fuel can be reliably injected by all the fuel injection nozzles. The control value is set. As a result, there are inherently fuel injection nozzles that inject more excess fuel than the intended microinjection amount, making it difficult to achieve good combustion in all cylinders. There is a problem that the fuel consumption of the engine deteriorates as a whole, and a problem that NOx, PM, etc. in the exhaust gas discharged from the internal combustion engine deteriorate.

  In relation to this problem, in a hybrid vehicle having an internal combustion engine and a motor generator (motor generator), a micro fuel injection means for injecting micro fuel when the internal combustion engine is motored by the motor generator, and micro fuel There is disclosed a control device for an internal combustion engine provided with a fuel injection amount learning means that estimates and learns an actual fuel injection amount with respect to a required fuel injection amount based on a change in motoring power when a fuel is injected (for example, , See Patent Document 1).

  However, in this control device for an internal combustion engine of a hybrid vehicle, the estimation learning of the actual fuel injection amount is performed based on a change in electric power for driving the motor generator in motoring. In order to improve the sensitivity of the engine, the rotational speed of the internal combustion engine is set low to reduce the friction of the internal combustion engine, and the detection accuracy is relatively improved. However, the internal combustion engine is stably motored and the motor If the ring power is not stable, the measurement error becomes large, and there is a problem that the time required for learning becomes long.

JP 2010-159649 A

  The present invention has been made in view of the above, and an object of the present invention is to use a minute amount such as pilot injection or after injection in fuel injection control of the internal combustion engine in a hybrid vehicle in which the internal combustion engine can be driven by a motor generator. An object of the present invention is to provide a hybrid vehicle capable of setting and updating a minimum injection amount control value for injecting fuel in accordance with a machine difference of an internal combustion engine and a secular change, and a control method thereof.

In order to achieve the above object, a hybrid vehicle of the present invention has a function of driving an internal combustion engine with a motor generator, and includes a traveling state detection means for detecting a traveling state of the vehicle, and rotation of a crankshaft of the internal combustion engine. In a hybrid vehicle including a hybrid system including a rotation speed detection means for detecting a speed and a motor output torque detection means for detecting a motor output torque of the motor generator, the running state detection means causes the motor generator to When it is detected that the internal combustion engine is being driven, the crankshaft rotational speed of the internal combustion engine is maintained at a preset rotational speed for detection, and then the fuel injection of the internal combustion engine is performed. When the control value is increased from 0 for each minimum control unit and the control value for fuel injection of the internal combustion engine is increased for each minimum control unit, the rotation speed is detected. It is determined whether an increase in the rotational speed of the crankshaft detected by the stage occurs, and the fuel injection amount when the increase in the rotational speed of the crankshaft occurs in this measurement is detected as a first minimum injection amount control value The first injection control value detecting means, and while the internal combustion engine is being driven by the motor generator, the rotational speed of the crankshaft maintains the same rotational speed as the rotational speed for detection, Second injection control for detecting a second minimum injection amount control value for injecting the minimum unit amount of fuel in the fuel injection control of the internal combustion engine based on the fluctuation of the motor output torque detected by the motor output torque detecting means. a value detecting means, and injection control value updating means for setting or updating a first minimum injection quantity control value which is detected by the first minimum injection control value detecting means as a minimum injection amount control value, the second injection system Using a second minimum injection quantity control value which is detected by the value detection unit configured to include a hybrid control device having an injection control value correcting means for correcting the first minimum injection amount control value.

  In order to provide a motoring function for driving the internal combustion engine with the motor generator, the internal combustion engine and the motor generator are configured to be directly coupled, and the drive source side of the internal combustion engine and the motor generator and the wheel side of the vehicle are configured. Is configured so that torque is not transmitted between the drive source side and the wheel side by connecting via a clutch and disengaging the clutch.

  When the vehicle is stopped, all cylinders in the internal combustion engine are injected with fuel during motoring in which the transmission is neutral and the clutch is disengaged so that torque is not transmitted between the drive source side and the wheel side. The crankshaft of the internal combustion engine is rotated by the motor output torque generated by the motor generator by the electric power of the traveling battery. At this time, the fuel injection control value is increased for each control unit, whether or not the crankshaft rotational speed fluctuates is measured, and the fuel injection control value at the time when the rotational speed fluctuates is determined. The first minimum injection amount control value is detected by setting the first minimum injection amount control value.

  According to this configuration, whether or not a minute amount of fuel has been injected based on fluctuations in the rotational speed of the crankshaft of the internal combustion engine when the vehicle is stopped and the internal combustion engine is driven by the motor generator. Therefore, it is possible to set and update the minimum injection amount control value that varies depending on the machine difference of the internal combustion engine, with very high accuracy.

  Accordingly, the injection amount of the fuel injection can be accurately controlled in minute units, and precise fuel injection control can be performed in the internal combustion engine, so that the combustion in the cylinder is brought into an optimal combustion state and discharged from the internal combustion engine. NOx and PM in the exhaust gas emitted can be reduced, combustion efficiency can be improved, and fuel consumption can be improved.

A hybrid vehicle control method for achieving the above object is a hybrid vehicle control method having a function of driving an internal combustion engine with a motor generator when the internal combustion engine is being driven by the motor generator. Then, after the rotational speed of the crankshaft of the internal combustion engine is maintained at a preset rotational speed for detection, the control value for fuel injection of the internal combustion engine is increased from 0 for each minimum control unit, and the internal combustion engine is the control value of the fuel injection of the engine when raised for each minimum unit of control, measure or increase in the rotational speed of the crankshaft occurs, when the increase in the rotational speed of the crankshaft in this measurement occurs rotation of the fuel injection amount and detects a first minimum injection amount control value, when in driving the internal combustion engine by the motor generator, the rotational speed of the crankshaft for the detection A second minimum injection for injecting a minimum unit amount of fuel in the fuel injection control of the internal combustion engine based on fluctuations in motor output torque of the motor generator after maintaining the same rotational speed as An amount control value is detected, and the detected first minimum injection amount control value is set or updated as a minimum injection amount control value, and the first minimum injection amount control value is used to detect the first minimum injection amount control value. This is a method characterized by correcting the injection amount control value .

  According to these methods, the same effect as the above hybrid vehicle can be obtained.

  According to the hybrid vehicle and the control method thereof of the present invention, when the hybrid vehicle is stopped and the internal combustion engine is driven by the motor generator, the minute amount is determined based on the fluctuation in the rotational speed of the crankshaft of the internal combustion engine. Therefore, it is possible to set and update the minimum injection amount control value that differs depending on the machine difference of each body of the internal combustion engine with very high accuracy.

  Accordingly, the injection amount of the fuel injection can be accurately controlled in a minute unit, and precise fuel injection control can be performed in the internal combustion engine, so that the optimal combustion in the cylinder can be achieved without injecting excess fuel. In the combustion state, NOx and PM in the exhaust gas discharged from the internal combustion engine can be reduced, combustion efficiency can be improved, and fuel consumption can be improved.

It is a figure which shows the structure of the hybrid vehicle of embodiment of this invention, and is a figure which shows the state of the engine independent driving | running | working with the engine output torque of an internal combustion engine. It is a figure which shows the structure of the hybrid vehicle of FIG. 1, and is a figure which shows the state of the motoring which drives the internal combustion engine with the motor output torque of a motor generator. It is a figure which shows the structure of the minimum fuel injection control value learning system. It is a figure which shows the method of the minimum fuel injection control value learning. It is a schematic diagram for demonstrating the method to set and update the minimum injection amount control value. It is a schematic diagram for demonstrating the selection method of the control curve which shows the relationship between a fuel injection amount control value and a fuel injection amount.

  Hereinafter, a hybrid vehicle and a control method thereof according to an embodiment of the present invention will be described. As shown in FIGS. 1 and 2, a hybrid vehicle (HEV: hereinafter referred to as a vehicle) 1 of this embodiment includes both an internal combustion engine (engine) 10 and a motor generator (running motor / generator) 20. It is a hybrid vehicle used as a power source for traveling.

  As shown in FIG. 1, the engine output torque Te generated by the operation of the internal combustion engine 10 includes a coupling clutch 13 that connects and disconnects the internal combustion engine 10 and the motor generator 20, the motor generator 20, and the drive clutch. 14, transmitted to a transmission (transmission) 30 via a torque converter 15, further transmitted to a differential gear (differential device) 32 via a propeller shaft 31, and transmitted to a wheel 34 via an axle 33. 1 runs.

  On the other hand, regarding the motor output torque Tm of the motor generator 20, the electric power charged (charged) in the traveling battery 22 is supplied to the motor generator 20 via the inverter 21 to generate the motor output torque Tm. The motor output torque Tm is transmitted to the transmission 30 via the driving clutch 14 and the torque converter 15 in the connected state, and further transmitted to the wheels 34 via the propeller shaft 31 so that the vehicle 1 travels.

  That is, in the engine independent traveling in which the wheels 34 are rotationally driven only by the internal combustion engine 10, the internal combustion engine 10 is operated with the coupling clutch 13 and the driving clutch 14 connected as shown in FIG. Is idle. Further, in the motor-assisted traveling in which the motor generator 20 is added to the internal combustion engine 10 and the wheels 34 are rotationally driven, the coupling clutch 13 and the driving clutch 14 are connected as shown in FIG. The generator 20 is operated to generate both engine output torque Te and motor output torque Tm.

  Further, in the motor independent traveling in which the wheels 34 are rotationally driven only by the motor generator 20, the internal combustion engine 10 is stopped or idled, or the coupling clutch 13 provided in the internal combustion engine 10 and the motor generator 20 is disconnected. At the same time, the drive clutch 14 is brought into the connected state, and the motor generator 20 is operated to generate the motor output torque Tm.

  Further, in the motor power generation traveling in which the motor generator 20 is driven by the internal combustion engine 10 to generate electric power and the wheels 34 are rotationally driven, the coupling clutch 13 and the driving clutch 14 are connected as shown in FIG. The engine 10 is operated to generate the engine output torque Te, the motor generator 20 is operated in the power generation mode to generate electric power, and the traveling battery 22 is charged via the inverter 21.

  Further, in the motor power generation in which the motor generator 20 is driven by the internal combustion engine 10 to generate power while the vehicle 1 is stopped, the coupling clutch 13 is in the connected state and the driving clutch 14 is in the disconnected state, although not shown. The internal combustion engine 10 is operated to generate the engine output torque Te, the motor generator 20 is operated in the power generation mode to generate electric power, and the traveling battery 22 is charged via the inverter 21.

  In the case of motor power generation in which the motor generator 20 is driven by using the braking torque Ts of the vehicle 1 as the regenerative torque when the vehicle 1 is braked, the drive clutch 14 is connected and the motor generator 20 is set in the power generation mode. The vehicle is operated to generate power, and the traveling battery 22 is charged via the inverter 21. At this time, in accordance with the magnitude of the braking torque Ts, the coupling clutch 13 is connected to apply the engine braking force of the internal combustion engine 10, or the coupling clutch 13 is disconnected.

  In the present invention, when the vehicle 1 is shipped, the minimum injection amount control value Fmin, which is a control amount that can reliably inject the minimum amount of fuel so that the minute injection can be accurately performed in the fuel injection control of the internal combustion engine 10. And the minimum injection amount control value Fmin is updated after a preset period has elapsed.

  At this time, as shown in FIG. 2, while the vehicle 1 is stopped, the coupling clutch 13 is connected and the driving clutch 14 is disconnected, and the internal combustion engine is driven by the motor output torque Tm of the motor generator 20. The internal combustion engine 10 that drives the motor 10 is motored.

  In FIG. 1, the engine generated torque (including engine brake torque and the like) Te of the internal combustion engine 10 and the motor output torque of the motor generator 20 depend on the combination of connection and disconnection switching of the coupling clutch 13 and the driving clutch 14. The transmission torque from one or both driving sides of Tm (including motor braking torque) to the wheel 34 is cut off and the regenerative torque from the wheel 34 side is switched by connecting and disconnecting the driving clutch 14. Although transmission and interruption to the motor generator 20 are performed, if the transmission and interruption of torque between the internal combustion engine 10 and the motor generator 20 can be switched as appropriate, the coupling clutch 13 may not be provided. If the transmission and interruption of torque between the drive side and the axle side of the engine 10 and the motor generator 20 can be switched as appropriate, the drive clutch 14 is Kenaku may be.

  Further, in the internal combustion engine 10, since the exhaust gas G generated by the combustion in the internal combustion engine 10 contains NOx (nitrogen oxide), PM (Particulate Matter), etc., the NOx reduction catalyst device 12a. And an exhaust gas purifying device 12 and an exhaust gas temperature sensor 42 provided with a PM collecting filter device 12b, a differential pressure sensor 41, and the like are disposed in the exhaust passage 11, and the exhaust gas purifying device 12 NOx, PM, etc. are purified. The purified exhaust gas Gc is released into the atmosphere via a muffler (not shown) or the like.

  And the control apparatus 40 for controlling the engine 10, the motor generator 20, the hybrid system, and the vehicle 1 is provided, and the motor generator 20 by the inverter 21 is provided by the hybrid control apparatus 40a incorporated in the control apparatus 40. And the overall control of the hybrid system including the connection / disconnection control of the coupling clutch 13 and the connection / disconnection control of the drive clutch 14.

  In this internal combustion engine 10, in order to reduce NOx and PM in the exhaust gas G discharged from the internal combustion engine 10 and improve combustion efficiency and improve fuel efficiency, fuel injection in a cylinder (cylinder) is performed. Therefore, it is very important that the actual minute fuel injection is performed with the minute injection amount for the purpose of control. Therefore, in the present invention, as shown in FIG. 3, in addition to the running state detecting means 61S, the rotational speed detecting means 62S, and the motor output torque detecting means 63S, a minimum fuel injection control value learning system 50S is provided. Has been.

  The running state detecting means 61S is a means for detecting the running state of the vehicle, and the rotational speed detecting means 62S is a means for detecting the rotational speed Vc of the crankshaft of the internal combustion engine 10, and is attached to the end of the crankshaft. A crank angle sensor that reads the rotation of a gear called a crankshaft timing rotor can be used. This crank angle sensor generates an electric signal (Ne signal) that becomes a voltage HIGH when approaching the convex portion of the gear, and a voltage LOW near the concave portion, and rotates in a very short time from the change interval of this voltage. Variation in the speed Vc can be detected. The motor output torque detection means 63S is means for detecting the motor output torque Tm of the motor generator 20. These means are provided in a conventional hybrid vehicle and are well-known techniques.

  Further, as shown in FIG. 3, the minimum fuel injection control value learning system 50S provided in the hybrid control device 40a includes a first injection control value detection means 51S, an injection control value update means 52S, and a second injection control value. It comprises a detecting means 53S and an injection control value correcting means 54S.

  The first injection control value detecting means 51S detects the crankshaft detected by the rotational speed detecting means 62S when the running state detecting means 61S detects that the motor generator 20 is driving the internal combustion engine 10. Based on the fluctuation of the rotational speed Vc, a first minimum injection amount control value F1 for injecting the minimum unit amount of fuel in the fuel injection control of the internal combustion engine 10 is detected. The first injection control value detecting means 51S detects the first minimum injection amount control value F1 for injecting the minimum unit amount of fuel in the fuel injection control of the internal combustion engine 10 for each cylinder of the internal combustion engine 10. Preferably, it is configured.

  The injection control value update unit 52S is a unit that sets or updates the first minimum injection amount control value F1 detected by the first injection control value detection unit 51S as the minimum injection amount control value Fmin.

  Then, the second injection control value detecting means 53S is a fuel for the internal combustion engine 10 based on the fluctuation of the motor output torque Tm detected by the motor output torque detecting means 63S while the motor generator 20 is driving the internal combustion engine 10. This is means for detecting a second minimum injection amount control value F2 for injecting a minimum unit amount of fuel in the injection control. The second injection control value detection means 53S is configured to detect a second minimum injection amount control value F2 for injecting a minimum unit amount of fuel in the fuel injection control of the internal combustion engine 10 for each cylinder of the internal combustion engine. It is preferred that

  Further, the injection control value correction means 54S uses the second minimum injection amount control value F2 detected by the second injection control value detection means 53S to set or update the minimum injection amount control in the injection control value update means 52S. Means for correcting the value Fmin.

  Next, a hybrid vehicle control method according to the present invention will be described with reference to FIG. In this control method, the hybrid control device 40a sets the minimum injection amount control value Fmin when the vehicle 1 is shipped, and updates the minimum injection amount control value Fmin after a preset period has elapsed. In this setting and updating, the vehicle 1 is stopped, the transmission 30 is set to neutral, the drive clutch 14 is disengaged, and the coupling clutch 13 is engaged as shown in FIG. Thus, the internal combustion engine 10 is driven by the motor output torque Tm generated by the motor generator 20. Driving the internal combustion engine 10 with the motor generator 20 is called motoring.

  Based on the fluctuation of the rotational speed Vc of the crankshaft detected by the rotational speed detecting means 62S when the traveling state detecting means 61S detects that the motor generator 20 is driving the internal combustion engine 10, A first minimum injection amount control value F1 for injecting a minimum unit amount of fuel in the fuel injection control of the internal combustion engine 10 is detected.

  As shown in FIG. 5, in this detection, during motoring, the fuel injection of all cylinders in the internal combustion engine 10 is stopped to zero, and the motor output torque Tm0 generated by the motor generator 20 by the electric power of the battery 22 for traveling is used. The crankshaft of the internal combustion engine 10 is rotated. After a state in which the preset rotational speed for detection Vc1 is maintained (t0), the fuel injection control value Ft is increased for each control unit ΔF to determine whether or not the crankshaft rotational speed Vc varies. The first minimum injection amount control value is measured by setting the fuel injection control value Ft1 at the time t1 when the rotation speed Vc fluctuates, that is, when the rotation speed Vc increases, as the first minimum injection amount control value F1. F1 is detected.

  Note that the preset rotational speed Vc1 for detection is set to a rotational speed Vc that is likely to vary due to fuel injection and that can easily detect this variation, through experiments or the like. This rotational speed Vc1 may be one or plural in order to increase detection accuracy.

  In the common rail type fuel injection system, this control unit ΔF is the minimum unit of electric power supplied for opening the fuel injection nozzle, for example, in the case of Duty, it is the minimum unit time for increasing the energization time.

  The detected first minimum injection amount control value F1 is set or updated as the minimum injection amount control value Fmin. At this time, it is preferable to detect and set or update the first minimum injection amount control value F1 for injecting the minimum unit amount of fuel in the fuel injection control of the internal combustion engine 10 for each cylinder of the internal combustion engine 10. .

  At the same time, the second minimum injection amount control value F2 for injecting the minimum unit amount of fuel in the fuel injection control of the internal combustion engine 10 based on the fluctuation of the motor output torque Tm detected by the motor output torque detecting means 53S. Is detected.

  As shown in FIG. 5, in this detection, during motoring, the fuel injection of all cylinders in the internal combustion engine 10 is stopped to zero, and the motor output torque Tm0 generated by the motor generator 20 by the power of the traveling battery 22 is generated. The crankshaft of the internal combustion engine 10 is rotated. The fuel injection control value Ft increases every control unit ΔF after the preset rotation speed for detection is maintained (t0), and the motor output torque Tm varies, that is, the motor output torque Tm decreases. The second minimum injection amount control value F2 is determined by measuring whether the fuel output torque Tm fluctuates and setting the fuel injection control value Ft2 at the time t2 when the motor output torque Tm fluctuates as the second minimum injection amount control value F2. To detect.

Note that the preset rotational speed Vc for detection is set to a rotational speed Vc2 that is likely to vary due to fuel injection and that can easily detect this variation, through experiments or the like . Further, the rotational speed Vc2 may be one or plural in order to improve detection accuracy. However, by setting the rotation speed Vc2 to the rotation speed Vc1, the first minimum injection amount control value F1 and the second minimum injection amount control value F2 can be detected at the same time, so that setting or updating can be performed more efficiently. it can.

  Then, the minimum injection amount control value set or updated by the injection control value updating unit 52S using the second minimum injection amount control value F2 detected by the second injection control value detecting unit 53S by the injection control value correcting unit 54S. Fmin is corrected. At this time, the second minimum injection amount control value F2 for injecting the minimum unit amount of fuel in the fuel injection control of the internal combustion engine 10 may be detected for each cylinder of the internal combustion engine 10 and corrected for each cylinder. preferable.

  As this correction method, the average value of the first minimum injection amount control value F1 and the second minimum injection amount control value F2 is simply set to the minimum injection amount control value Fmin, or the first minimum injection amount control value F1 and second The weighted average value of the minimum injection amount control value F2 is set to the minimum injection amount control value Fmin.

  Then, along with the setting and updating of the minimum injection amount control value Fmin, as shown in FIG. 6, how much injection amount control value F should be output to the fuel injection nozzle in order to obtain the fuel injection amount Q. From the control curves L1, L2,... Preset control curves, the fuel injection amount Q is zero in each control curve L1, L2,..., That is, the fuel injection amount at a position intersecting the horizontal axis Is selected as the minimum injection amount control value Fmin (L4 in FIG. 6), or the initially set control curve is shifted to the minimum injection amount control value Fmin in the horizontal axis direction.

  According to the vehicle 1 configured as described above and its control method, when the internal combustion engine 10 is driven by the motor generator 20 when the vehicle 1 is stopped, the rotational speed Vc of the crankshaft of the internal combustion engine 10 varies. Based on this, since it is possible to accurately detect whether or not a minute amount of fuel has been injected, it is possible to set and update the minimum injection amount control value Fmin that varies depending on the machine difference of the internal combustion engine 10 with very high accuracy.

  Therefore, the injection amount of the fuel injection can be accurately controlled in a minute amount unit, and precise fuel injection control can be performed in the internal combustion engine 10, so that the combustion in the cylinder is optimal without injecting excess fuel. Thus, NOx and PM in the exhaust gas G discharged from the internal combustion engine 10 can be reduced, combustion efficiency can be improved, and fuel consumption can be improved.

  Then, the second minimum injection amount control value F2 is obtained based not only on the fluctuation of the rotational speed Vc of the crankshaft of the internal combustion engine 10 but also on the motor output torque Tm of the motor generator 20, and the first minimum injection quantity control is obtained. When the minimum injection amount control value Fmin set or updated based on the value F1 is corrected, the minimum injection amount control value Fmin can be set and updated with higher accuracy.

  Further, when the first minimum injection amount control value F1 and the second minimum injection amount control value F2 are detected for each cylinder of the internal combustion engine 10, the minimum injection amount control value Fmin can be set and changed for each cylinder of the internal combustion engine 10. Therefore, since precise fuel injection control of the internal combustion engine 10 can be performed in all cylinders, the combustion in each cylinder is brought into an optimal combustion state without injecting excess fuel, and is discharged from the internal combustion engine 10. NOx and PM in the exhaust gas G can be further reduced, combustion efficiency can be further improved, and fuel consumption can be further improved.

1 Vehicle (Hybrid vehicle: HEV)
10 Internal combustion engine
DESCRIPTION OF SYMBOLS 12 Exhaust-gas purification apparatus 13 Coupling clutch 14 Drive clutch 15 Torque converter 20 Motor generator 21 Inverter 22 Traveling battery 30 Transmission 34 Wheel 40 Control device (ECU)
40a Hybrid control device 50S Minimum fuel injection control value learning system 51S First injection control value detection means 52S Injection control value update means 53S Second injection control value detection means 54S Injection control value correction means 61S Traveling state detection means 62S Rotation speed detection means 63S Motor output torque detection means F1 First minimum injection amount control value F2 Second minimum injection amount control value Fmin Minimum injection amount control value Ft Fuel injection control value G Exhaust gas Gc Exhaust gas L1, L2,... After purification Control curve Q Fuel injection amount t0 Time when the preset rotational speed for detection is maintained t1 Time when the crankshaft rotational speed increases Te Engine output torque Tm Motor output torque Tm0 Motor during motoring Output torque Vc Crankshaft rotational speeds Vc1, Vc2 Detecting rotational speed ΔF Fuel injection Your unit

Claims (2)

A driving state detecting means for detecting the driving state of the vehicle, a rotational speed detecting means for detecting a rotational speed of a crankshaft of the internal combustion engine, and a motor generator for driving the internal combustion engine with a motor generator ; In a hybrid vehicle including a hybrid system including motor output torque detection means for detecting motor output torque ,
When the traveling state detecting means detects that the internal combustion engine is being driven by the motor generator, the rotational speed of the crankshaft of the internal combustion engine maintains a preset rotational speed for detection. Then, when the control value for fuel injection of the internal combustion engine is increased from 0 for each minimum control unit, and the control value for fuel injection for the internal combustion engine is increased for each minimum control unit, the rotational speed detecting means Is measured to detect whether an increase in the rotational speed of the crankshaft is detected, and the fuel injection amount when the increase in the rotational speed of the crankshaft is detected in this measurement is detected as a first minimum injection amount control value. First injection control value detection means;
The motor detected by the motor output torque detecting means after the rotation speed of the crankshaft maintains the same rotation speed as the detection rotation speed while driving the internal combustion engine with the motor generator Second injection control value detection means for detecting a second minimum injection amount control value for injecting a minimum unit amount of fuel in the fuel injection control of the internal combustion engine based on fluctuations in output torque;
And injection control value updating unit for setting or updating the minimum injection amount control value of the first minimum injection quantity control value which is detected by the first minimum injection control value detecting means,
A hybrid control device having injection control value correcting means for correcting the first minimum injection amount control value using the second minimum injection amount control value detected by the second injection control value detecting means is configured. A hybrid vehicle characterized by that. In a control method of a hybrid vehicle having a function of driving an internal combustion engine with a motor generator,
Control of fuel injection of the internal combustion engine after the rotational speed of the crankshaft of the internal combustion engine maintains a preset rotational speed for detection when the internal combustion engine is being driven by the motor generator The value is increased from 0 for each minimum control unit, and when the control value for fuel injection of the internal combustion engine is increased for each minimum control unit, it is measured whether the increase in the rotational speed of the crankshaft occurs. While detecting the fuel injection amount when an increase in the rotational speed of the crankshaft occurs in the measurement as a first minimum injection amount control value ,
When the motor generator is driving the internal combustion engine, the crankshaft rotational speed is maintained at the same rotational speed as the detection rotational speed. Detecting a second minimum injection amount control value for injecting a minimum unit amount of fuel in the fuel injection control of the internal combustion engine based on the fluctuation;
The detected first minimum injection amount control value is set or updated as a minimum injection amount control value, and the first minimum injection amount control value is corrected using the detected second minimum injection amount control value. A control method of a hybrid vehicle characterized by the above.

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