JP2010120510A - Internal combustion engine, hybrid car equipped with the same, and fuel property determination method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To properly and early determine the property of fuel to be supplied to an internal combustion engine at the start of an engine. <P>SOLUTION: After fuel injection to an engine or the ignition of the engine is started in response to a request to start the engine (S150), an estimated output power Peest of the engine is calculated as a sum of a power used for the rise of the revolving speed Ne of the engine per time dt and a power generated by a motor per the time dt (S170), and when the estimated output power Peest becomes larger than a predetermined power Pref during the rise of the revolving speed Ne of the engine, it is determined that fuel to be supplied to the engine is light oil (S180, S200), and when the estimated output power Peest is equal to or less than the predetermined power Pref continuously during the rise of the revolving speed Ne of the engine, it is determined that fuel to be supplied to the engine is heavy oil (S180, S190). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an internal combustion engine device, a hybrid vehicle including the same, and a fuel property determination method.

Conventionally, this type of internal combustion engine device includes an engine and a generator capable of cranking the engine and capable of generating electricity using the power of the engine, and when the engine is requested to start, the engine is cranked. The engine is controlled so that the engine rotational speed becomes a predetermined rotational speed, and the engine is started so that fuel injection and ignition to the engine are started at a predetermined timing. (For example, refer to Patent Document 1). In this device, whether or not the fuel supplied to the engine based on the amount of power generated per unit time by the generator is a heavy fuel with low volatility after the start of the engine is completed and the engine speed is stabilized. Is judged.
JP 2001-41094 A

  However, in the above-described apparatus, since the fuel property is determined after the engine start is completed and the engine speed is stabilized, the engine misfires or the fuel injection amount is excessive before the engine speed is stabilized. May occur. If the control at the time of starting is performed using light fuel, the amount of fuel injection will be small compared to the case of heavy fuel, but if the actual fuel supplied to the engine is heavy, misfire will occur. This will cause emissions to deteriorate. On the other hand, if the control at the time of starting is performed using heavy fuel, the amount of fuel increase is increased in order not to cause misfire. Therefore, when the actual fuel supplied to the engine is light, the fuel injection amount is excessive. End up.

  An internal combustion engine device of the present invention, a hybrid vehicle including the same, and a fuel property determination method are mainly intended to determine the property of fuel supplied to an internal combustion engine more appropriately and earlier when the internal combustion engine is started.

  The internal combustion engine device of the present invention, the hybrid vehicle including the same, and the fuel property determination method employ the following means in order to achieve the above-described main object.

The internal combustion engine device of the present invention is
An internal combustion engine, an electric motor capable of cranking the internal combustion engine and capable of generating electric power using power from the internal combustion engine, and the electric motor so that the internal combustion engine is cranked when the start of the internal combustion engine is requested An internal combustion engine that controls the internal combustion engine such that fuel injection and ignition to the internal combustion engine are started and the internal combustion engine is started when a predetermined fuel injection condition is satisfied. Engine equipment,
A rotational speed detection means for detecting the rotational speed of the internal combustion engine;
The rotation of the internal combustion engine per predetermined time is increased when the detected rotational speed of the internal combustion engine is increased after the start of the internal combustion engine is requested and fuel injection and ignition to the internal combustion engine are started. The fuel property for determining that the property of the fuel supplied to the internal combustion engine is heavy when the sum of the power used for increasing the number and the power generated by the electric motor per predetermined time is less than or equal to a predetermined value A determination means;
It is a summary to provide.

  In this internal combustion engine device of the present invention, when the engine speed is increased after the start of the internal combustion engine is requested and the fuel injection and ignition to the internal combustion engine are started, the internal combustion engine per predetermined time is increased. When the sum of the power used to increase the number of revolutions and the power generated by the electric motor per predetermined time is less than a predetermined value, it is determined that the property of the fuel supplied to the internal combustion engine is heavy. Thereby, the property of the fuel supplied to the internal combustion engine can be determined more appropriately and earlier.

  In such an internal combustion engine apparatus of the present invention, the start control means is a fuel to be injected into the internal combustion engine when the fuel property determination means does not determine that the property of the fuel supplied to the internal combustion engine is heavy. The fuel injection amount is the first fuel injection amount, and when the fuel property determination means determines that the fuel supplied to the internal combustion engine is heavy, the fuel injection amount to be injected into the internal combustion engine is the first fuel injection amount. It is also possible that the second fuel injection amount is larger than the fuel injection amount. If it carries out like this, an internal combustion engine can be started more appropriately based on the property of the fuel supplied to an internal combustion engine.

The hybrid vehicle of the present invention
The internal combustion engine apparatus of the present invention according to any one of the above-described aspects, that is, an internal combustion engine, and an electric motor capable of cranking the internal combustion engine and generating electric power using power from the internal combustion engine, When the start of the internal combustion engine is requested, the electric motor is controlled so that the internal combustion engine is cranked, and fuel injection and ignition to the internal combustion engine are started when a predetermined fuel injection condition is satisfied. An internal combustion engine apparatus comprising: a start control unit that controls the internal combustion engine so that the internal combustion engine is started, and a rotation speed detection unit that detects a rotation speed of the internal combustion engine; The power used for increasing the rotational speed of the internal combustion engine per predetermined time when the detected rotational speed of the internal combustion engine is rising after the start of fuel injection and ignition to the internal combustion engine. And an internal combustion engine comprising: a fuel property determining means for determining that the property of the fuel supplied to the internal combustion engine is heavy when the sum of the power generated by the electric motor per predetermined time is equal to or less than a predetermined value Equipment,
The remaining shaft is connected to the three shafts of the output shaft of the internal combustion engine, the drive shaft connected to the axle, and the rotating shaft of the electric motor, and based on the power input to and output from any two of the three shafts 3-axis power input / output means for inputting / outputting power to / from,
A second electric motor capable of inputting and outputting power to the drive shaft;
Power storage means capable of exchanging electric power with the electric motor and the second electric motor;
With
The fuel property determination means is a means for determining the property of the fuel supplied to the internal combustion engine when the start of the internal combustion engine is requested in a state where the vehicle is stopped.
This is the gist.

  Since the hybrid vehicle of the present invention includes the internal combustion engine device of the present invention according to any one of the above-described aspects, the effects of the internal combustion engine device of the present invention, for example, the fuel supplied to the internal combustion engine when the internal combustion engine is started. The same effect as the effect that the property can be determined more appropriately and earlier can be obtained. The “three-axis power input / output means” includes a single pinion type or double pinion type planetary gear mechanism, a differential gear, and the like.

The fuel property determination method of the present invention includes:
An internal combustion engine, an electric motor capable of cranking the internal combustion engine and capable of generating electric power using power from the internal combustion engine, and the electric motor so that the internal combustion engine is cranked when the start of the internal combustion engine is requested An internal combustion engine that controls the internal combustion engine such that fuel injection and ignition to the internal combustion engine are started and the internal combustion engine is started when a predetermined fuel injection condition is satisfied. A fuel property determination method for determining a property of fuel supplied to the internal combustion engine in an engine device,
An increase in the rotational speed of the internal combustion engine per predetermined time when the rotational speed of the internal combustion engine is increasing after a start of the internal combustion engine is requested and fuel injection and ignition to the internal combustion engine are started. When the sum of the power used for the predetermined time and the power generated by the electric motor per predetermined time is not more than a predetermined value, it is determined that the property of the fuel supplied to the internal combustion engine is heavy.
It is characterized by that.

  The fuel property determination method according to the present invention provides an internal combustion engine per predetermined time when the rotational speed of the internal combustion engine increases after the fuel injection and ignition to the internal combustion engine for which the start of the internal combustion engine is requested. When the sum of the power used to increase the engine speed and the power generated by the electric motor per predetermined time is equal to or less than a predetermined value, it is determined that the property of the fuel supplied to the internal combustion engine is heavy. Thereby, the property of the fuel supplied to the internal combustion engine can be determined more appropriately and earlier.

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

  FIG. 1 is a configuration diagram showing an outline of the configuration of a hybrid vehicle 20 equipped with an internal combustion engine device according to an embodiment of the present invention. As shown in the figure, the hybrid vehicle 20 of the embodiment includes an engine 22, a three-shaft power distribution / integration mechanism 30 connected to a crankshaft 26 as an output shaft of the engine 22 via a damper 28, and power distribution / integration. A motor MG1 capable of generating electricity connected to the mechanism 30, a reduction gear 35 attached to a ring gear shaft 32a as a drive shaft connected to the power distribution and integration mechanism 30, a motor MG2 connected to the reduction gear 35, And a hybrid electronic control unit 70 for controlling the entire vehicle. Here, as the internal combustion engine device of the embodiment, mainly, the engine 22, the motor MG1 connected to the engine 22 through the power distribution and integration mechanism 30, the hybrid electronic control unit 70, and the electronic control for engine which will be described later. The unit 24 corresponds.

  The engine 22 is configured as an internal combustion engine capable of outputting power using a hydrocarbon-based fuel such as gasoline or light oil, and the air purified by an air cleaner 122 is passed through a throttle valve 124 as shown in FIG. Inhalation and gasoline are injected from the fuel injection valve 126 to mix the sucked air and gasoline, and this mixture is sucked into the combustion chamber through the intake valve 128 and explosively burned by an electric spark from the spark plug 130. Thus, the reciprocating motion of the piston 132 pushed down by the energy is converted into the rotational motion of the crankshaft 26. Exhaust gas from the engine 22 is discharged to the outside air through a purification device (three-way catalyst) 134 that purifies harmful components such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx).

  The engine 22 is controlled by an engine electronic control unit (hereinafter referred to as engine ECU) 24. The engine ECU 24 is configured as a microprocessor centered on the CPU 24a, and includes a ROM 24b that stores a processing program, a RAM 24c that temporarily stores data, an input / output port and a communication port (not shown), in addition to the CPU 24a. . The engine ECU 24 detects signals from various sensors that detect the state of the engine 22, for example, the crank position θ from the crank position sensor 140 that detects the rotational position of the crankshaft 26 and the coolant temperature of the engine 22. The cooling water temperature Tw from the water temperature sensor 142, the cam position from the cam position sensor 144 that detects the rotational position of the intake valve 128 that performs intake and exhaust to the combustion chamber and the camshaft that opens and closes the exhaust valve, and the position of the throttle valve 124 are detected. Throttle position from the throttle valve position sensor 146, intake air amount Qa from the air flow meter 148 attached to the intake pipe, intake air temperature from the temperature sensor 149 also attached to the intake pipe, air-fuel ratio from the air-fuel ratio sensor 135a, oxygen Such as oxygen signal from capacitors 135b is input via the input port. The engine ECU 24 also integrates various control signals for driving the engine 22, such as a drive signal to the fuel injection valve 126, a drive signal to the throttle motor 136 that adjusts the position of the throttle valve 124, and an igniter. The control signal to the ignition coil 138 and the control signal to the variable valve timing mechanism 150 that can change the opening / closing timing of the intake valve 128 are output via the output port. The engine ECU 24 is in communication with the hybrid electronic control unit 70, controls the operation of the engine 22 by a control signal from the hybrid electronic control unit 70, and outputs data related to the operation state of the engine 22 as necessary. The engine ECU 24 also calculates the rotational speed of the crankshaft 26, that is, the rotational speed Ne of the engine 22 based on the crank position θ from the crank position sensor 140.

  The power distribution and integration mechanism 30 includes an external gear sun gear 31, an internal gear ring gear 32 arranged concentrically with the sun gear 31, a plurality of pinion gears 33 that mesh with the sun gear 31 and mesh with the ring gear 32, A planetary gear mechanism is provided that includes a carrier 34 that holds a plurality of pinion gears 33 so as to rotate and revolve, and that performs differential action using the sun gear 31, the ring gear 32, and the carrier 34 as rotational elements. In the power distribution and integration mechanism 30, the crankshaft 26 of the engine 22 is connected to the carrier 34, the motor MG1 is connected to the sun gear 31, and the reduction gear 35 is connected to the ring gear 32 via the ring gear shaft 32a. When functioning as a generator, power from the engine 22 input from the carrier 34 is distributed according to the gear ratio between the sun gear 31 side and the ring gear 32 side, and when the motor MG1 functions as an electric motor, the engine input from the carrier 34 The power from 22 and the power from the motor MG1 input from the sun gear 31 are integrated and output to the ring gear 32 side. The power output to the ring gear 32 is finally output from the ring gear shaft 32a to the drive wheels 63a and 63b of the vehicle via the gear mechanism 60 and the differential gear 62.

  The motor MG1 and the motor MG2 are both configured as well-known synchronous generator motors that can be driven as generators and can be driven as motors, and exchange power with the battery 50 via inverters 41 and 42. The power line 54 connecting the inverters 41 and 42 and the battery 50 is configured as a positive electrode bus and a negative electrode bus shared by the inverters 41 and 42, and the electric power generated by one of the motors MG1 and MG2 It can be consumed by a motor. Therefore, battery 50 is charged / discharged by electric power generated from one of motors MG1 and MG2 or insufficient electric power. If the balance of electric power is balanced by the motors MG1 and MG2, the battery 50 is not charged / discharged. The motors MG1 and MG2 are both driven and controlled by a motor electronic control unit (hereinafter referred to as a motor ECU) 40. The motor ECU 40 detects signals necessary for driving and controlling the motors MG1 and MG2, such as signals from rotational position detection sensors 43 and 44 that detect the rotational positions of the rotors of the motors MG1 and MG2, and current sensors (not shown). The phase current applied to the motors MG1 and MG2 to be applied is input, and a switching control signal to the inverters 41 and 42 is output from the motor ECU 40. The motor ECU 40 is in communication with the hybrid electronic control unit 70, controls the driving of the motors MG1 and MG2 by a control signal from the hybrid electronic control unit 70, and, if necessary, data on the operating state of the motors MG1 and MG2. Output to the hybrid electronic control unit 70. The motor ECU 40 also calculates the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 based on signals from the rotational position detection sensors 43 and 44.

  The battery 50 is managed by a battery electronic control unit (hereinafter referred to as a battery ECU) 52. The battery ECU 52 receives signals necessary for managing the battery 50, for example, a voltage between terminals from a voltage sensor (not shown) installed between terminals of the battery 50, and a power line 54 connected to the output terminal of the battery 50. The charging / discharging current from the attached current sensor (not shown), the battery temperature Tb from the temperature sensor 51 attached to the battery 50, and the like are input. Output to the control unit 70. Further, the battery ECU 52 calculates the remaining capacity (SOC) based on the integrated value of the charging / discharging current detected by the current sensor in order to manage the battery 50, and calculates the remaining capacity (SOC) and the battery temperature Tb. The input / output limits Win and Wout, which are the maximum allowable power that may charge / discharge the battery 50, are calculated based on the above. The input / output limits Win and Wout of the battery 50 are set to the basic values of the input / output limits Win and Wout based on the battery temperature Tb, and the output limiting correction coefficient and the input are set based on the remaining capacity (SOC) of the battery 50. It can be set by setting a correction coefficient for restriction and multiplying the basic value of the set input / output restrictions Win and Wout by the correction coefficient.

  The hybrid electronic control unit 70 is configured as a microprocessor centered on the CPU 72, and in addition to the CPU 72, a ROM 74 for storing processing programs, a RAM 76 for temporarily storing data, an input / output port and communication not shown. And a port. The hybrid electronic control unit 70 includes an ignition signal from an ignition switch 80, a shift position SP from a shift position sensor 82 that detects the operation position of the shift lever 81, and an accelerator pedal position sensor 84 that detects the amount of depression of the accelerator pedal 83. The accelerator pedal opening Acc from the vehicle, the brake pedal position BP from the brake pedal position sensor 86 for detecting the depression amount of the brake pedal 85, the vehicle speed V from the vehicle speed sensor 88, and the like are input via the input port. As described above, the hybrid electronic control unit 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via the communication port, and exchanges various control signals and data with the engine ECU 24, the motor ECU 40, and the battery ECU 52. ing.

  The hybrid vehicle 20 of the embodiment thus configured calculates the required torque to be output to the ring gear shaft 32a as the drive shaft based on the accelerator opening Acc and the vehicle speed V corresponding to the depression amount of the accelerator pedal 83 by the driver. Then, the operation of the engine 22, the motor MG1, and the motor MG2 is controlled so that the required power corresponding to the required torque is output to the ring gear shaft 32a. As operation control of the engine 22, the motor MG1, and the motor MG2, the operation of the engine 22 is controlled so that power corresponding to the required power is output from the engine 22, and all of the power output from the engine 22 is the power distribution and integration mechanism 30. Torque conversion operation mode for driving and controlling the motor MG1 and the motor MG2 so that the torque is converted by the motor MG1 and the motor MG2 and output to the ring gear shaft 32a, and the required power and the power required for charging and discharging the battery 50. The engine 22 is operated and controlled so that suitable power is output from the engine 22, and all or part of the power output from the engine 22 with charging / discharging of the battery 50 is the power distribution and integration mechanism 30, the motor MG1, and the motor. The required power is converted to the ring gear shaft 32 with torque conversion by MG2. Charge / discharge operation mode in which the motor MG1 and the motor MG2 are driven and controlled so as to be output to each other, and a motor operation mode in which the operation of the engine 22 is stopped and the power corresponding to the required power from the motor MG2 is output to the ring gear shaft 32a. and so on.

  Next, the operation of the hybrid vehicle 20 of the embodiment thus configured, particularly the operation when starting the engine 22 in a state where the vehicle is stopped will be described. FIG. 3 is a flowchart showing an example of a stop-time start control routine executed by the hybrid electronic control unit 70. This routine is executed when a start of the engine 22 is requested in a state where the vehicle is stopped by a brake mechanism (not shown) or a parking lock mechanism (not shown). For example, the remaining capacity (SOC) of the battery 50 is lowered while the vehicle is stopped. This is executed when the battery 50 is requested to be charged, or when the ignition switch 80 is pressed at a low temperature (for example, the temperature is less than −15 ° C.).

  When the stop-time start control routine is executed, the CPU 72 of the hybrid electronic control unit 70 first controls the crank position θ of the engine 22, the rotational speed Ne of the engine 22, the rotational speeds Nm1, Nm2 of the motors MG1, MG2, and the like. Processing for inputting necessary data is executed (step S100). Here, the crank position θ of the engine 22 is detected by the crank position sensor 140 and input from the engine ECU 24 by communication. Further, the rotational speed Ne of the engine 22 is calculated based on the crank position θ detected by the crank position sensor 140 and is input from the engine ECU 24 by communication. Further, the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 are input from the motor ECU 40 by communication from those calculated based on the rotational positions of the rotors of the motors MG1 and MG2 detected by the rotational position detection sensors 43 and 44. It was supposed to be.

  When the data is input in this way, the torque command Tm1 * of the motor MG1 is set based on the torque map at the start, the elapsed time t from the start of the engine 22 and the rotational speed Ne of the engine 22 (step S110). FIG. 4 shows an example of a torque map set in the torque command Tm1 * of the motor MG1 when the engine 22 is started and an example of a change in the rotational speed Ne of the engine 22. In the torque map of the embodiment, rate processing is used so that the rotational speed Ne of the engine 22 quickly passes through a resonance rotational speed band (for example, 400 rpm to 500 rpm, etc.) immediately after the time t11 when the start instruction of the engine 22 is given. A relatively large torque is set in the torque command Tm1 *. Then, from the time t12 when the engine speed Ne reaches the ignition start engine speed Nfire (for example, 900 rpm or 1000 rpm), the engine speed Ne reaches the start completion engine speed Nef (for example, 1100 rpm or 1200 rpm). The torque for power generation is set to the torque command Tm1 * in order to reduce the torque shock caused by the explosion combustion of the engine 22 until t13. Here, the ignition start rotation speed Nfire is the rotation speed at which the fuel injection control and the ignition control of the engine 22 are started, and the start completion rotation speed Nef is a rotation speed at which it is determined that the start of the engine 22 has been completed.

  Next, the set torque command Tm1 * of the motor MG1 is pushed by dividing the gear ratio ρ (the number of teeth of the sun gear 31 / the number of teeth of the ring gear 32) of the power distribution and integration mechanism 30 and the gear ratio Gr of the reduction gear 35. A torque command Tm2 * to be output from the motor MG2 by adding the contact torque Tp is calculated by the following equation (1) (step S120). Here, the pressing torque Tp is used to suppress the rattling when the engine 22 is operated with the gears such as the reduction gear 35, the power distribution and integration mechanism 30, and the gear mechanism 60 being packed. Can be used as the torque to be output from the motor MG2 and can be determined in advance through experiments or the like in consideration of the characteristics of the vehicle. Expression (1) is a dynamic relational expression for the rotating element of the power distribution and integration mechanism 30. FIG. 5 is a collinear diagram showing the dynamic relationship between the rotational speed and torque of each rotary element of the power distribution and integration mechanism 30 when the engine 22 is started. In the figure, the left S-axis indicates the rotation speed of the sun gear 31 that is the rotation speed Nm1 of the motor MG1, the C-axis indicates the rotation speed of the carrier 34 that is the rotation speed Ne of the engine 22, and the R-axis indicates the rotation speed of the motor MG2. The rotational speed Nr of the ring gear 32 obtained by dividing the number Nm2 by the gear ratio Gr of the reduction gear 35 is shown. Expression (1) can be easily derived by using this alignment chart. It is assumed that the braking force is acting on the vehicle while the vehicle is stopped and a brake mechanism (not shown) or a parking lock mechanism (not shown), and the vehicle does not move depending on the pressing torque Tp.

  Tm2 * = Tm1 * / (ρ ・ Gr) + Tp (1)

  When the torque commands Tm1 * and Tm2 * for the motors MG1 and MG2 are set in this way, the set torque commands Tm1 * and Tm2 * are transmitted to the motor ECU 40 (step S130), and the rotational speed Ne of the engine 22 is set to the ignition start rotational speed Nfire. (Step S140), when the rotation speed Ne of the engine 22 is less than the ignition start rotation speed Nfire, the processes of steps S100 to S140 are repeatedly executed to continue the cranking of the engine 22. Receiving the torque commands Tm1 * and Tm2 *, the motor ECU 40 controls the switching elements of the inverters 41 and 42 so that the motor MG1 is driven by the torque command Tm1 * and the motor MG2 is driven by the torque command Tm2 *. .

  If the engine speed Ne reaches the ignition start engine speed Nfire while the engine 22 is being cranked (step S140), a fuel injection signal is issued so that fuel is injected into the engine 22. Is transmitted to the engine ECU 24 (step S150). The engine ECU 24 that has received the fuel injection signal performs control such as intake air amount control, fuel injection control, and ignition control in the engine 22 so that the engine 22 is operated at a start completion speed Nef that is higher than the ignition start speed Nfire. Take control. Here, the fuel injection control is performed based on the target fuel injection amount τ * set by the fuel injection amount setting routine shown in FIG. Hereinafter, the description of the stop-time start control routine of FIG. 3 will be temporarily interrupted, and a fuel injection amount setting routine executed by the engine ECU 24 will be described.

  In the fuel injection amount setting routine of FIG. 6, the CPU 24a of the engine ECU 24 inputs the intake air amount Qa from the air flow meter 148 and the light fuel flag F (step S300) and checks the value of the input light fuel flag F (step S300). Step S310). Here, the light fuel flag F is a flag that is set by the stop-time start control routine of FIG. 3, and is reset to a value of 0 when the start of the engine 22 is requested as an initial value and supplied to the engine 22. A value of 1 is set when it is determined that the fuel is light enough to vaporize. When the light fuel flag F has a value of 0, it is determined that the fuel supplied to the engine 22 is not light, that is, is heavy that is difficult to vaporize, and a predetermined coefficient k1 is set as the fuel injection coefficient k (step S320). The target fuel injection amount τ * is set by multiplying the fuel injection coefficient k by the intake air amount Qa (step S340), and the fuel injection amount setting routine is ended. On the other hand, when the light fuel flag F has a value of 1, it is determined that the fuel supplied to the engine 22 is light, and a predetermined coefficient k2 smaller than the predetermined coefficient k1 is set as the fuel injection coefficient k (step S330). The target fuel injection amount τ * is set by multiplying the fuel injection coefficient k by the intake air amount Qa (step S340), and the fuel injection amount setting routine is ended. That is, when the fuel supplied to the engine 22 is heavy, the target fuel injection amount τ * is set larger than when the fuel is light. This is because when the fuel supplied to the engine 22 is heavy, a large amount of fuel adheres to the intake port or intake valve 128 or combustion becomes unstable, so that the target output cannot be obtained from the engine 22. Based on fear. In the embodiment, when the start of the engine 22 is requested, the fuel supplied to the engine 22 is heavy until the property of the fuel supplied to the engine 22 is determined in order to suppress inconvenience such as misfire of the engine 22. In this case, the target fuel injection amount τ * is set. For this reason, the light fuel flag F is reset to 0 when the engine 22 is requested to start.

  The fuel injection amount setting routine in FIG. 6 has been described above. Returning to the description of the stop-time start control routine of FIG. When fuel injection control or the like is performed in the engine 22 using the target fuel injection amount τ * set in this way (step S150), the value of the light fuel flag F is subsequently checked (step S160), and the light fuel flag is checked. When F is 0, that is, when it is determined that the fuel supplied to the engine 22 is heavy, the generated power obtained by multiplying the torque command Tm1 * of the motor MG1 by the current rotational speed Nm1 of the motor MG1. Multiply (power consumption) by the time dt (value 0 at the first execution) since the previous execution of step S170 and the inertia moment Ie of the engine 22 by the angular acceleration αe of the engine 22 and further Crank position change amount dθ (initial actual value) that crankshaft 26 of engine 22 has rotated since the previous step S170 was executed. When the value 0) is calculated by the following equation (2) the estimated output power Peest which is estimated to be outputted from the engine 22 as the sum of the multiplied by the (step S170). Here, the inertia moment Ie of the engine 22 may be a value determined in advance based on the characteristics of the engine 22 or the like, and may be a constant or a value based on the temperature Ne of the engine 22 or the coolant temperature Tw. Good. Further, the angular acceleration αe of the engine 22 can be obtained by multiplying the time derivative of the rotational speed Ne of the engine 22 by a value 2π (2π · dNe / dt). In Expression (2), the first term on the right side corresponds to the power generated by the motor MG1 per time dt, and the second term on the right side corresponds to the power used to increase the rotational speed Ne of the engine 22 per time dt. To do. This is because when the vehicle is stopped, the rotational speed Nr of the ring gear shaft 32a as the drive shaft has a value of 0. Therefore, the output from the engine 22 is mainly the power used to change the rotational speed Ne of the engine 22 and the motor MG1. Based on the equivalent of the sum of the power generated by In this way, by calculating the estimated output power Pest of the engine 22 in consideration of the power used to increase the rotational speed Ne of the engine 22, the engine 22 is in a transient state when the rotational speed Ne of the engine 22 changes. The output from 22 can be estimated more appropriately.

  Peest = (-Tm1 * ・ Nm1) ・ dt + (Ie ・ 2π ・ dNe / dt) ・ dθ (2)

  When the estimated output power Peest of the engine 22 is calculated in this way, the calculated estimated output power Peest is compared with a predetermined power Pref (step S180). Here, the predetermined power Pref is used to determine the property of the fuel supplied to the engine 22, and is output from the engine 22 when the engine 22 is started when the fuel supplied to the engine 22 is light. As a value slightly smaller than a value estimated to reach power, a value determined in advance through experiments or the like can be used. When the estimated output power Peest of the engine 22 is less than or equal to the predetermined power Pref, it is determined that the fuel supplied to the engine 22 is heavy, a value 0 is set in the light fuel flag F (step S190), and the engine 22 rotates. The number Ne is compared with the start completion rotational speed Nef that determines that the start of the engine 22 has been completed (step S210). When the rotation speed Ne of the engine 22 is less than the start completion rotation speed Nef, it is determined that the rotation speed Ne of the engine 22 is still increasing toward the start completion rotation speed Nef, and the start of the engine 22 is not completed, When the estimated output power Pest is less than the predetermined power Pref, steps S100 to S190 are repeatedly executed. When the engine speed Ne reaches the start completion speed Nef (step S210), it is determined that the engine 22 has been started. Then, the start control routine at the time of stop is completed. When the stop-time start control routine is completed with the light fuel flag F set to 0, it is executed when the engine 22 is being operated assuming that the fuel supplied to the engine 22 is heavy. An engine operation control routine (not shown) is executed.

  On the other hand, when the estimated output power Pest of the engine 22 becomes larger than the predetermined power Pref when the rotational speed Ne of the engine 22 is increasing toward the start completion rotational speed Nef (step S180), the fuel supplied to the engine 22 Is determined to be light, the value 1 is set in the light fuel flag F (step S200), and when the engine speed Ne is less than the start completion speed Nef (step S210), the above-described steps S100 to S140 are performed. The processing is executed, and fuel injection control in the engine 22 is performed using the light fuel target fuel injection amount τ * set in the fuel flag setting routine of FIG. 6 (step S150). Then, it is determined in step S160 that the light fuel flag F has a value of 1, and thereafter, the light fuel flag F remains at a value of 1 (step S200) until the rotational speed Ne of the engine 22 reaches the start completion rotational speed Nef. (Step S210), the processes of Steps S100 to S160, S200, and S210 are repeatedly executed. When the rotational speed Ne of the engine 22 reaches the start completion rotational speed Nef (Step S210), the stop-time start control routine is terminated. When the stop-time start control routine ends with the light fuel flag F set to 1, an engine operation time control routine (not shown) is executed assuming that the fuel supplied to the engine 22 is light.

  FIG. 7 is a schematic view illustrating the change in the rotational speed Ne and the change in the estimated output power Peest when the engine 22 is started. In the figure, the solid line indicates when the fuel supplied to the engine 22 is light, and the broken line indicates when the fuel supplied to the engine 22 is heavy. In addition, the same code | symbol is attached | subjected about the time corresponded to the same time as the map of FIG. 4 mentioned above. As shown in the figure, when the rotational speed Ne of the engine 22 reaches the ignition start rotational speed Nfire (time t12), fuel injection control in the engine 22 is started assuming that the fuel supplied to the engine 22 is heavy, and the engine 22 The estimated output power Pest 22 is larger when the fuel supplied to the engine 22 is light (solid line) than when it is heavy (broken line). When the fuel supplied to the engine 22 is heavy (broken line), the estimated output power Pest is continuously determined while the rotational speed Ne of the engine 22 increases toward the start completion rotational speed Nef. The target fuel injection amount τ * for heavy fuel is set below the power Pref, and the fuel injection amount control in the engine 22 is performed. On the other hand, when the fuel supplied to the engine 22 is light (solid line), it is determined that the fuel supplied to the engine 22 is light at time t21 when the estimated output power Peest is greater than the predetermined power Pref. After t21, the target fuel injection amount τ * for light fuel is set, and fuel injection control in the engine 22 is performed. Thereby, when the fuel supplied to the engine 22 is light, it can suppress that fuel injection is performed more than necessary, and can improve an emission and a fuel consumption. Further, as described above, the estimated output power Pest of the engine 22 is calculated in consideration of the power used to increase the rotational speed Ne of the engine 22, and the engine 22 is thus based on the calculated estimated output power Pest. Since the fuel property to be supplied is determined, the fuel property supplied to the engine 22 is more appropriately determined and the fuel injection control of the engine 22 is performed even during a transient time when the rotational speed Ne of the engine 22 changes. It can be performed more appropriately.

  According to the hybrid vehicle 20 of the embodiment described above, after the start of the engine 22 is requested and the fuel injection or ignition to the engine 22 is started, the rotation speed Ne of the engine 22 per time dt as an execution interval. The estimated output power Pest of the engine 22 is calculated as the sum of the power used for the increase and the power generated by the motor MG1 per time dt, and the rotation speed Ne of the engine 22 increases toward the start completion rotation speed Nef. When the estimated output power Peest becomes larger than the predetermined power Pref during this time, it is determined that the fuel supplied to the engine 22 is light, and the rotational speed Ne of the engine 22 increases toward the start completion rotational speed Nef. When the estimated output power Peest is less than or equal to the predetermined power Pref, the engine 22 is supplied. That fuel from determined to be heavy, can be determined more appropriately and more swiftly property of fuel supplied to the engine 22. In addition, since the fuel injection control of the engine 22 is performed with the target fuel injection amount τ * suitable for the determined fuel property, the engine 22 can be started more appropriately.

  In the hybrid vehicle 20 of the embodiment, when the start of the engine 22 is requested, the target fuel injection amount τ * is set assuming that the fuel is heavy until the property of the fuel supplied to the engine 22 is determined. However, the target fuel injection amount τ * may be set assuming that the fuel is light until the fuel property is determined. In this case, the fuel supplied to the engine 22 when the estimated output power Peest of the engine 22 is equal to or lower than the predetermined power Pref continues while the rotational speed Ne of the engine 22 increases toward the start completion rotational speed Nef. It is determined that the engine 22 is heavy, and then the engine 22 is controlled using the target fuel injection amount τ * for heavy fuel.

  In the hybrid vehicle 20 of the embodiment, when the property of the fuel supplied to the engine 22 is light, the target fuel injection amount τ * is set larger than that when the property of the fuel is heavy. Regardless of the properties of the fuel, the target fuel injection amount τ * may be set to be the same, or the ignition timing and the intake air amount may be changed based on the properties of the fuel.

  In the hybrid vehicle 20 of the embodiment, the fuel injection and ignition to the engine 22 are started when the rotation speed Ne of the engine 22 reaches the ignition start rotation speed Nfire as a fuel injection condition to the engine 22. The fuel injection or ignition to the engine 22 may be started when a predetermined time has elapsed since the engine 22 was instructed to start.

  In the hybrid vehicle 20 of the embodiment, the power of the motor MG2 is shifted by the reduction gear 35 and output to the ring gear shaft 32a. However, as illustrated in the hybrid vehicle 120 of the modified example of FIG. May be output to an axle (an axle connected to the wheels 64a and 64b in FIG. 8) different from an axle to which the ring gear shaft 32a is connected (an axle to which the drive wheels 63a and 63b are connected).

  In the hybrid vehicle 20 of the embodiment, the power of the engine 22 is output to the ring gear shaft 32a as the drive shaft connected to the drive wheels 63a and 63b via the power distribution and integration mechanism 30, but the modified example of FIG. As illustrated in the hybrid vehicle 220, a generator 230 that generates power by the power from the engine 22, and a motor MG that outputs power to the axles of the drive wheels 63a and 63b by the power from the generator 230 and the battery 50, A so-called series hybrid vehicle may be provided. In this case, the property of the fuel supplied to the engine 22 is determined not only when the start of the engine 22 is requested in a stopped state but also when the start of the engine 22 is requested while the vehicle is running. Can do.

  Further, the present invention is not limited to those applied to such hybrid vehicles, but is applicable to non-moving facilities such as forms of internal combustion engine devices mounted on moving bodies such as trains other than automobiles, ships, and aircraft, and construction facilities. An internal combustion engine device incorporated may be used. Furthermore, it is good also as a form of the control method of such an internal combustion engine apparatus.

  Here, the correspondence between the main elements of the embodiments and the modified examples and the main elements of the invention described in the column of means for solving the problems will be described. In the embodiment, the engine 22 corresponds to the “internal combustion engine”, the motor MG1 corresponds to the “electric motor”, and when the engine 22 is requested to start, the torque map at the time of start and the progress from the start of the engine 22 start. A torque command Tm1 * of the motor MG1 is set based on the time t and the rotational speed Ne of the engine 22, and a torque command Tm2 * of the motor MG2 is output so as to travel by outputting the required torque Tr * to the ring gear shaft 32a as a drive shaft. 3 is set and transmitted to the motor ECU 40. When the engine speed Ne reaches the ignition start engine speed Nfire or more, a fuel injection signal is transmitted to the engine ECU 24 so that fuel injection to the engine 22 is started. Hybrid electronic control unit 70 for executing steps S110 to S150 of the start control routine, and intake air The fuel injection amount setting routine of FIG. 6 for setting the target fuel injection amount τ * based on Qa and the light fuel flag F is executed, and ignition control, intake air amount control, and set target fuel injection are performed based on the fuel injection signal. The engine ECU 24 that performs fuel injection amount control by the amount τ * and the motor ECU 40 that controls the motors MG1 and MG2 based on the torque commands Tm1 * and Tm2 * correspond to “startup control means”. The crank position sensor 140 that detects the rotational position and the engine ECU 24 that calculates the rotational speed Ne of the engine 22 based on the detected crank position θ correspond to the “rotational speed detection means”. After the fuel injection or ignition to the engine 22 is started, the engine 22 per time dt as an execution interval. The estimated output power Pest of the engine 22 is calculated as the sum of the power used to increase the rotational speed Ne and the power generated by the motor MG1 per time dt, and the rotational speed Ne of the engine 22 is calculated as the start complete rotational speed Nef. When the estimated output power Peest becomes larger than the predetermined power Pref while the engine is rising, it is determined that the fuel supplied to the engine 22 is light, and the rotational speed Ne of the engine 22 is directed toward the start completion rotational speed Nef. When the estimated output power Pest is continuously below the predetermined power Pref while increasing, the fuel supplied to the engine 22 is judged to be heavy. The hybrid electronic control unit 70 that executes is equivalent to “fuel property determination means”. Further, the power distribution and integration mechanism 30 corresponds to “three-axis power input / output means”, the motor MG2 corresponds to “second electric motor”, and the battery 50 corresponds to “power storage means”.

  Here, the “internal combustion engine” is not limited to an internal combustion engine that outputs power using a hydrocarbon fuel such as gasoline or light oil, and may be any type of internal combustion engine such as a hydrogen engine. The “motor” is not limited to the motor MG2 configured as a synchronous generator motor, but may be an induction motor or the like that can crank the internal combustion engine and generate power using power from the internal combustion engine. Any type of electric motor may be used. The “starting time control means” is not limited to the combination of the hybrid electronic control unit 70, the engine ECU 24, and the motor ECU 40, and may be configured by a single electronic control unit. Further, as the “starting time control means”, when the engine 22 is requested to start, the motor MG1 is based on the torque map at the time of starting, the elapsed time t from the start of starting the engine 22, and the rotational speed Ne of the engine 22. Torque command Tm1 * and a torque command Tm2 * of the motor MG2 are set so as to drive the ring gear shaft 32a as a drive shaft and the motor MG1 and MG2 are controlled. When the rotational speed Ne reaches the ignition start rotational speed Nfire or more, the target fuel injection amount τ * is set based on the intake air amount Qa or the light fuel flag F and the engine 22 is controlled. When the engine is requested to start, the motor is controlled so that the internal combustion engine is cranked, and when a predetermined fuel injection condition is satisfied. If the fuel injection and ignition are started to combustion engine controls the internal combustion engine as the internal combustion engine is started may be any ones. The “fuel property determining means” is used to increase the rotational speed Ne of the engine 22 per time dt as an execution interval after the start of the engine 22 is requested and fuel injection or ignition to the engine 22 is started. The estimated output power Pest of the engine 22 is calculated as the sum of the generated power and the power generated by the motor MG1 per time dt, and the rotational speed Ne of the engine 22 increases toward the start completion rotational speed Nef. When the estimated output power Peest becomes larger than the predetermined power Pref, it is determined that the fuel supplied to the engine 22 is light, and continues while the rotational speed Ne of the engine 22 increases toward the start completion rotational speed Nef. When the estimated output power Peest is less than or equal to the predetermined power Pref, the fuel supplied to the engine 22 is heavy It is not limited to the specified one, and when the engine speed is detected after the start of the internal combustion engine is requested and the fuel injection and ignition to the internal combustion engine are started, When the sum of the power used to increase the rotational speed of the internal combustion engine per hour and the power generated by the electric motor per predetermined time is less than or equal to a predetermined value, the property of the fuel supplied to the internal combustion engine is heavy Anything can be used as long as it is determined. Further, the “three-axis power input / output means” is not limited to the power distribution and integration mechanism 30 described above, and uses a double pinion planetary gear mechanism, a combination of a plurality of planetary gear mechanisms, Any one of the three shafts connected to the three shafts of the output shaft of the internal combustion engine, the drive shaft coupled to the axle, and the rotating shaft of the electric motor, such as a differential gear having an operation action different from that of the planetary gear. As long as the power is input / output to / from the remaining shafts based on the power input / output to / from the shafts, any device may be used. The “second electric motor” is not limited to the motor MG2 configured as a synchronous generator motor, and may be any type of electric motor such as an induction motor that can input and output power to the drive shaft. It doesn't matter. The “storage means” is not limited to the battery 50 as a secondary battery, and may be anything as long as it can exchange electric power with an electric motor or a second electric motor such as a capacitor.

  Note that the correspondence between the main elements of the embodiment and the modified example and the main elements of the invention described in the column of means for solving the problem is described in the column of means for the embodiment to solve the problem. Since this is an example for specifically describing the best mode for carrying out the invention, the elements of the invention described in the column of means for solving the problems are not limited. That is, the interpretation of the invention described in the column of means for solving the problems should be made based on the description of the column, and the examples are those of the invention described in the column of means for solving the problems. It is only a specific example.

  The best mode for carrying out the present invention has been described with reference to the embodiments. However, the present invention is not limited to these embodiments, and various modifications can be made without departing from the gist of the present invention. Of course, it can be implemented in the form.

  The present invention can be used in the manufacturing industry of internal combustion engine devices and hybrid vehicles.

1 is a configuration diagram showing an outline of the configuration of a hybrid vehicle 20 equipped with an internal combustion engine device according to an embodiment of the present invention. 2 is a configuration diagram showing an outline of the configuration of an engine 22. FIG. 5 is a flowchart showing an example of a start control routine at the time of stopping executed by the hybrid electronic control unit 70. It is explanatory drawing which shows an example of the torque map set to the torque command Tm1 * of motor MG1 at the time of engine 22 start, and an example of the mode of the rotation speed Ne of the engine 22. It is explanatory drawing which shows the collinear diagram which shows the dynamic relationship between the rotation speed of each rotation element of the power distribution integration mechanism 30 at the time of starting the engine 22, and a torque. 5 is a flowchart showing an example of a fuel injection amount setting routine executed by an engine ECU 24. It is a schematic diagram which illustrates the mode of the change of the rotation speed Ne at the time of starting of the engine 22, and the change of estimated output power Peest. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 120 according to a modification. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 220 of a modified example.

Explanation of symbols

  20, 120, 220 Hybrid vehicle, 22 engine, 24 engine electronic control unit (engine ECU), 24a CPU, 24b ROM, 24c RAM, 26 crankshaft, 28 damper, 30 power distribution integration mechanism, 31 sun gear, 32 ring gear, 32a ring gear shaft, 33 pinion gear, 34 carrier, 35 reduction gear, 40 motor electronic control unit (motor ECU), 41, 42 inverter, 43, 44 rotational position detection sensor, 50 battery, 51 temperature sensor, 52 battery electronic control Unit (battery ECU), 54 power line, 60 gear mechanism, 62 differential gear, 63a, 63b drive wheel, 64a, 64b wheel, 70 hybrid electronic control unit, 72 CPU, 74 R OM, 76 RAM, 80 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 86 brake pedal position sensor, 88 vehicle speed sensor, 122 air cleaner, 124 throttle valve, 126 Fuel injection valve, 128 intake valve, 130 spark plug, 132 piston, 134 purification device, 135a air-fuel ratio sensor, 135b oxygen sensor, 136, throttle motor, 138 ignition coil, 140 crank position sensor, 142 water temperature sensor, 143 pressure sensor, 144 Cam position sensor, 146 Throttle valve position sensor, 148 Air flow meter, 149 Temperature sensor, 150 Change valve timing mechanism, 230 generators, MG1, MG2, MG motor.

Claims (4)

An internal combustion engine, an electric motor capable of cranking the internal combustion engine and capable of generating electric power using power from the internal combustion engine, and the electric motor so that the internal combustion engine is cranked when the start of the internal combustion engine is requested An internal combustion engine that controls the internal combustion engine such that fuel injection and ignition to the internal combustion engine are started and the internal combustion engine is started when a predetermined fuel injection condition is satisfied. Engine equipment,
A rotational speed detection means for detecting the rotational speed of the internal combustion engine;
The rotation of the internal combustion engine per predetermined time is increased when the detected rotational speed of the internal combustion engine is increased after the start of the internal combustion engine is requested and fuel injection and ignition to the internal combustion engine are started. The fuel property for determining that the property of the fuel supplied to the internal combustion engine is heavy when the sum of the power used for increasing the number and the power generated by the electric motor per predetermined time is less than or equal to a predetermined value A determination means;
An internal combustion engine device comprising: The internal combustion engine device according to claim 1,
The start control means determines the fuel injection amount to be injected to the internal combustion engine when the fuel property determination means does not determine that the fuel supplied to the internal combustion engine is heavy. When the fuel property determining means determines that the fuel supplied to the internal combustion engine is heavy, the second fuel injection amount to be injected into the internal combustion engine is larger than the first fuel injection amount. It is a means to make the fuel injection amount,
Internal combustion engine device. An internal combustion engine device according to claim 1 or 2,
The remaining shaft is connected to the three shafts of the output shaft of the internal combustion engine, the drive shaft connected to the axle, and the rotating shaft of the electric motor, and based on the power input to and output from any two of the three shafts 3-axis power input / output means for inputting / outputting power to / from,
A second electric motor capable of inputting and outputting power to the drive shaft;
Power storage means capable of exchanging electric power with the electric motor and the second electric motor;
With
The fuel property determination means is a means for determining the property of the fuel supplied to the internal combustion engine when the start of the internal combustion engine is requested in a state where the vehicle is stopped.
Hybrid car. An internal combustion engine, an electric motor capable of cranking the internal combustion engine and capable of generating electric power using power from the internal combustion engine, and the electric motor so that the internal combustion engine is cranked when the start of the internal combustion engine is requested An internal combustion engine that controls the internal combustion engine such that fuel injection and ignition to the internal combustion engine are started and the internal combustion engine is started when a predetermined fuel injection condition is satisfied. A fuel property determination method for determining a property of fuel supplied to the internal combustion engine in an engine device,
An increase in the rotational speed of the internal combustion engine per predetermined time when the rotational speed of the internal combustion engine is increasing after a start of the internal combustion engine is requested and fuel injection and ignition to the internal combustion engine are started. When the sum of the power used for the predetermined time and the power generated by the electric motor per predetermined time is not more than a predetermined value, it is determined that the property of the fuel supplied to the internal combustion engine is heavy.
A fuel property determination method characterized by the above.

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