JP4930419B2 - Internal combustion engine misfire determination apparatus, misfire determination method, and vehicle - Google Patents

Description

  The present invention relates to an internal combustion engine misfire determination device, a misfire determination method, and a vehicle.

Conventionally, as a misfire determination device for this type of internal combustion engine, in a vehicle that performs vibration suppression control so as to cancel torque fluctuation of the crankshaft of the engine by a motor, torque output from the motor is corrected for vibration suppression control by the motor. There has been proposed one that calculates a torque correction amount and detects a misfire state of the engine based on the torque correction amount of the motor (see, for example, Patent Document 1).
JP 2001-65402 A

  By the way, in a device mounted on a vehicle or the like that is connected to the engine crankshaft through a twisting element such as a damper, the torque fluctuation of the crankshaft due to the explosion combustion of the engine is caused by the twisting element or the twisting element. As a result of inducing a subsequent resonance and causing a rotational fluctuation in the crankshaft due to the resonance, even if it is attempted to detect a misfire of any cylinder of the engine based on the rotational fluctuation of the crank angle, it may not be detected accurately. is there.

  The main purpose of the misfire determination apparatus, misfire determination method, and vehicle of the present invention is to more accurately determine the misfire of a multi-cylinder internal combustion engine whose output shaft is connected to the subsequent stage shaft via a torsion element. And

  The misfire determination device, misfire determination method, and vehicle of the internal combustion engine of the present invention employ the following means in order to achieve the main object described above.

A misfire determination device for an internal combustion engine of the present invention,
A misfire determination device for determining misfire of a multi-cylinder internal combustion engine in which an output shaft is connected to a rear stage shaft via a torsion element,
A rear shaft rotational speed detection means for detecting a rear shaft rotational speed which is the rotational speed of the rear shaft;
Misfire determination means for determining misfire of the internal combustion engine based on the detected fluctuation amount of the rear shaft rotational speed or the fluctuation amount of the rear shaft related rotational speed which is the rotational speed related to the rear shaft rotational speed;
It is a summary to provide.

  In the misfire determination apparatus for an internal combustion engine according to the present invention, the internal combustion engine is operated based on the fluctuation amount of the rear-stage shaft rotation speed that is the rotation speed of the rear-stage shaft or the fluctuation amount of the rear-stage shaft related rotation speed that is the rotation speed related to the rear-stage shaft rotation speed. Determine the misfire of the engine. Thereby, even when it is difficult to accurately determine the misfire of the internal combustion engine based on the rotational fluctuation of the output shaft of the internal combustion engine due to the influence of resonance based on the twist of the torsion element, the misfire of the internal combustion engine can be more accurately determined. it can. Here, the “variation amount” includes wave height, amplitude, and the like.

  In such a misfire determination device for an internal combustion engine according to the present invention, the misfire determination means detects the filter processing that greatly attenuates in comparison with the resonance frequency in a band other than the resonance frequency based on the torsion of the torsion element. It is also possible to calculate the post-filter rotation speed by applying it to the rear-stage shaft rotation speed, and to determine misfire of the internal combustion engine using the calculated post-filter rotation speed as the rear-stage shaft-related rotation speed. If it carries out like this, misfire of an internal combustion engine can be determined using the rotation speed after a filter. In this case, the misfire determination means may be means for performing the filtering process on the detected rear shaft rotational speed with a frequency of once per two rotations of the internal combustion engine as the resonance frequency. it can. Further, the misfire determination means may be means for performing a process using a band-pass filter as the filter process for the detected rear shaft rotational speed.

  Further, in the misfire determination device for an internal combustion engine according to the present invention, the misfire determination means extracts a frequency component of resonance based on the twist of the torsion element with respect to the detected rear shaft rotational speed, and the extracted resonance The frequency component may be a means for determining misfire of the internal combustion engine using the rear shaft related rotational speed. If it carries out like this, misfire of an internal combustion engine can be determined more accurately using the frequency component of resonance.

  Further, in the misfire determination apparatus for an internal combustion engine according to the present invention, a rotational position detecting means for detecting a rotational position of the output shaft of the internal combustion engine, and the output shaft is a predetermined unit rotational angle based on the detected rotational position. Unit rotation angle rotation required time calculation means for calculating a unit rotation angle rotation required time which is a time required for rotation, and the misfire determination means includes a variation amount of the rear shaft rotation speed or the rear shaft related rotation. The misfire of the internal combustion engine may be determined based on the amount of fluctuation of the number, and the misfire of the internal combustion engine may be determined based on the calculated change in the required unit rotation angle rotation time.

The vehicle of the present invention
A multi-cylinder internal combustion engine whose output shaft is connected to the rear shaft of the rear stage via a torsion element;
The misfire determination apparatus for an internal combustion engine according to any one of the above-described aspects for determining misfire of the internal combustion engine, that is, a multi-cylinder internal combustion engine in which an output shaft is basically connected to a subsequent stage shaft via a torsion element A misfire determination apparatus for determining the misfire of the rear shaft, wherein the rear shaft rotational speed, which is the rotational speed of the rear shaft, is determined by the rear shaft rotational speed detection means, the detected variation amount of the rear shaft rotational speed, or the rear shaft rotational speed. A misfire determination means for determining the misfire of the internal combustion engine based on the amount of fluctuation of the rotation speed related to the rear shaft, which is the rotation speed related to the engine, and a misfire determination device for the internal combustion engine,
It is a summary to provide.

  Since the vehicle according to the present invention includes the misfire determination device for an internal combustion engine of the present invention according to any one of the above-described aspects, the effects exerted by the misfire determination device for the internal combustion engine of the present invention, for example, resonance based on torsion of a twist element. Even when it is difficult to accurately determine the misfire of the internal combustion engine based on the rotation fluctuation of the output shaft of the internal combustion engine due to the influence, the same effects as the effect of determining the misfire of the internal combustion engine with higher accuracy can be obtained.

  In such a vehicle of the present invention, an electric motor capable of outputting power to the rear shaft side downstream of the torsion element is provided, and the rear shaft rotation speed detection means detects the motor rotation speed that is the rotation speed of the motor. , And means for detecting the rotation speed of the rear shaft by converting the detected rotation speed of the motor. In this way, a relatively high-precision sensor that detects the rotation speed of the electric motor can also be used as the rear-stage shaft rotation speed detection means.

  Further, in the vehicle of the present invention, it is connected to the rear shaft and the axle side, and includes power power input / output means for inputting / outputting power to / from the rear shaft and the axle side with input / output of electric power and power, The electric motor is connected to the axle side so as to be able to output power, and the rear shaft rotation speed detection means also serves as a means for detecting the drive state of the power power input / output means, and the detected motor rotation speed It may be a means for detecting the rotational speed of the rear stage shaft by calculation based on the detected driving state.

The misfire determination method for an internal combustion engine of the present invention includes:
A misfire determination method for an internal combustion engine for determining misfire of a multi-cylinder internal combustion engine in which an output shaft is connected to a rear stage shaft through a torsion element,
The misfire of the internal combustion engine is determined based on a fluctuation amount of the rear-stage shaft rotation speed that is the rotation speed of the rear-stage shaft or a fluctuation amount of the rear-stage shaft-related rotation speed that is the rotation speed related to the rear-stage shaft rotation speed.
It is characterized by that.

  In the misfire determination method for an internal combustion engine according to the present invention, the misfire of the internal combustion engine is determined based on the fluctuation amount of the rear shaft rotation speed or the fluctuation amount of the rear shaft rotation speed, which is the rotation speed of the rear shaft. Thereby, even when it is difficult to accurately determine the misfire of the internal combustion engine based on the rotational fluctuation of the output shaft of the internal combustion engine due to the influence of resonance based on the twist of the torsion element, the misfire of the internal combustion engine can be more accurately determined. it can. Here, the “variation amount” includes wave height, amplitude, and the like.

  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 a configuration of a hybrid vehicle 20 equipped with an internal combustion engine misfire determination apparatus according to an embodiment of the present invention. As shown in the drawing, the hybrid vehicle 20 of the embodiment includes an engine 22 and a three-shaft power distribution and integration mechanism 30 connected to a crankshaft 26 as an output shaft of the engine 22 via a damper 28 as a torsion element. A motor MG1 capable of generating electricity connected to the power distribution and integration mechanism 30, a reduction gear 35 attached to the ring gear shaft 32a connected to the power distribution and integration mechanism 30, and a motor MG2 connected to the reduction gear 35; And a hybrid electronic control unit 70 for controlling the entire vehicle. Here, the misfire determination device for the internal combustion engine of the embodiment mainly corresponds to the engine electronic control unit 24 for controlling the engine 22.

  The engine 22 is configured as a 6-cylinder internal combustion engine that can output power using a hydrocarbon-based fuel such as gasoline or light oil. For example, as shown in FIG. The fuel is injected from the fuel injection valve 126 provided for each cylinder, and the intake air and the gasoline are mixed. The mixture is sucked into the combustion chamber through the intake valve 128 and ignited. The reciprocating motion of the piston 132 that is explosively burned by the electric spark generated by the plug 130 and 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 an 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. . In the engine ECU 24, signals from various sensors that detect the state of the engine 22, the crank position (crank angle CA) from the crank position sensor 140 that detects the rotational position of the crankshaft 26, and the coolant temperature of the engine 22 are displayed. Detects the coolant temperature from the water temperature sensor 142 to be detected, the cam position from the cam position sensor 144 to detect 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. The throttle position from the throttle valve position sensor 146, the amount of intake air from the air flow meter 148 attached to the intake pipe, the intake air temperature from the temperature sensor 149 also attached to the intake pipe, and the air-fuel ratio AF from the air-fuel ratio sensor 135a , Such as oxygen signal from oxygen sensor 135b via the input port is input. 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 above-described crank position sensor 140 is mounted so as to rotate in synchronization with the crankshaft 26, and teeth are formed every 10 degrees and two missing teeth are formed for detecting the reference position. It is configured as an electromagnetic pickup sensor having a rotor, and generates a shaped wave every time the crankshaft 26 rotates 10 degrees. The engine ECU 24 calculates the number of revolutions of the engine 22 as the number of revolutions Ne of the engine 22 based on the shaped wave from the crank position sensor 140 every time the crankshaft 26 rotates 30 degrees.

  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 carrier shaft 34 a connected to the carrier 34 is decelerated via the damper 28, the crankshaft 26 of the engine 22, the sun gear 31 is motor MG 1, and the ring gear 32 is decelerated via the ring gear shaft 32 a. When gears 35 are connected and motor MG1 functions as a generator, power from engine 22 input from carrier 34 is distributed to sun gear 31 side and ring gear 32 side according to the gear ratio, and motor MG1 When functioning as an electric motor, the power from the engine 22 input from the carrier 34 and the power from the motor MG1 input from the sun gear 31 are integrated and output to the ring gear 32 side. The power output to the ring gear 32 is finally output from the ring gear shaft 32a to the 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 rotational position detection sensors 43 and 44 are configured by a resolver, and the motor ECU 40 motors MG1 and MG2 at predetermined time intervals (for example, every 50 μsec or every 100 μsec) based on signals from the rotational position detection sensors 43 and 44. The rotation speeds Nm1 and Nm2 are calculated.

  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. The battery ECU 52 also calculates the remaining capacity (SOC) based on the integrated value of the charge / discharge current detected by the current sensor in order to manage the battery 50.

  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 a required torque to be output to the ring gear shaft 32a based on the accelerator opening Acc and the vehicle speed V corresponding to the amount of depression of the accelerator pedal 83 by the driver. The operation of the engine 22, the motor MG1, and the motor MG2 is controlled so that the required power corresponding to the 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 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, an operation for determining whether any cylinder of the engine 22 mounted in the hybrid vehicle 20 of the embodiment configured as described above has misfired will be described. FIG. 3 is a flowchart showing an example of a misfire determination process executed by the engine ECU 24. This routine is repeatedly executed every predetermined time.

  When the misfire determination process is executed, the CPU 24a of the engine ECU 24 first calculates the 30 degree rotation required time T30 calculated as the time required for the crankshaft 26 to rotate 30 degrees and the rotation speed on the rear stage side of the damper 28. A process of inputting the rotation speed Nc of the carrier 34 is executed (step S100). Here, as the time required for 30 degrees T30, the time calculated by the T30 calculation process illustrated in FIG. 4 is input. In the T30 calculation process of FIG. 4, every time the crank angle CA rotates 30 degrees based on the crank angle CA from the crank position sensor 140, the current time is input (step S300), and the current time and the previous crank angle CA are input. By calculating the difference from the time input when the motor rotates 30 degrees, the required time T30 of 30 degrees is calculated (step S310), and the T30 calculation process is terminated. Further, the rotation speed Nc of the carrier 34 is input from the hybrid electronic control unit 70 by communication, as calculated by the carrier rotation speed calculation process illustrated in FIG. In the carrier rotational speed calculation process of FIG. 5, the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 are input (step S400), and the input rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 and the gear ratio ρ of the power distribution and integration mechanism 30. Based on (the number of teeth of the sun gear / the number of teeth of the ring gear) and the reduction ratio Gr of the reduction gear 35, the rotational speed Nc of the carrier 34 is calculated by the equation (1) (step S410), and the calculated rotational speed Nc of the carrier 34 is calculated. Is transmitted to the engine ECU 24 (step S420), and the carrier rotational speed calculation process is terminated. Here, 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. To do.

  Nc = (Nm1 ・ ρ + Nm2 / Gr) / (1 + ρ) (1)

  When the data is input in this way, the input required 30 degree rotation time T30 is compared with the threshold value Tref (step S110), and when the 30 degree rotation use time T30 is larger than the threshold value Tref, any cylinder of the engine 22 has misfired. Is determined (step S150), and the misfire determination process is terminated. Here, the threshold value Tref is greater than the required 30 degree rotation time T30 when the cylinder that is in the combustion stroke is not misfiring at the crank angle CA that is the reference of the required 30 degree rotation time T30, and the cylinder is misfired. It is set as a value smaller than the time required for 30 degree rotation T30, and can be obtained by experiments or the like. In this case, the misfired cylinder can be identified as a cylinder that is in the combustion stroke at the crank angle CA that is the reference for the time required for 30-degree rotation T30 that exceeds the threshold Tref. FIG. 6 shows an example of a time change of the required rotation time T30 of the engine 22 and the crank angle CA when one cylinder of the engine 22 misfires. As shown in the drawing, the required rotation time T30 for the crank angle CA is once every 720 degrees and exceeds the threshold Tref. Since the crankshaft 26 of the engine 22 is connected to the carrier shaft 34a via the damper 28, the torque fluctuation of the crankshaft 26 induces resonance based on the torsion of the damper 28, and this resonance causes the crankshaft 26 and the carrier shaft 34a to rotate. The shaft 26 is caused to vary in rotation. Accordingly, the rotational fluctuation of the crankshaft 26 (the fluctuation of the time required for 30-degree rotation T30) is increased or decreased when the influence of torque fluctuation and the influence of resonance are emphasized or cancel each other. There is. In the former case, that is, when the fluctuation of the required rotation time T30 is large, when any cylinder of the engine 22 is misfiring, the required rotation time T30 corresponding to that cylinder exceeds the threshold value Tref. 22 can be determined, but in the latter case, that is, when the fluctuation of the time required for 30-degree rotation T30 is small, it corresponds to that cylinder even though any cylinder of the engine 22 is misfiring. The time required for 30-degree rotation T30 does not exceed the threshold value Terf, and it may be difficult to accurately determine the misfire of the engine 22.

  When the 30-degree rotation required time T30 is equal to or less than the threshold Tref in step S110, a bandpass filter is applied to the input rotation speed Nc of the carrier 34 to calculate a post-filter rotation speed FNc (step S120). Here, the band-pass filter is for extracting a frequency component of resonance generated based on the twist of the damper 28 from the rotational speed Nc of the carrier 34. An example of a bandpass filter is shown in FIG. As a band-pass filter, if the resonance based on the torsion of the damper 28 occurs in a misfire cycle (cycle in which the crankshaft 26 rotates twice (rotation 0.5 order)), the engine speed Ne is 1000 rpm. In some cases, a filter that attenuates the other band significantly (for example, 1/10 or less) without attenuating 8 Hz as a resonance frequency may be used. Therefore, the process of applying the bandpass filter to the rotation speed Nc of the carrier 34 is a process of extracting a resonance frequency component with respect to the rotation speed Nc of the carrier 34. By this processing, the post-filter rotation speed FNc can be made into a clean sinusoidal waveform with little noise. FIG. 8 shows an example of how the carrier speed Nc, the post-filter speed FNc, and the crank angle CA change with time. In FIG. 8, with respect to the carrier rotation speed Nc and the post-filter rotation speed FNc, the solid line indicates a state in which no cylinder of the engine 22 is misfired, and the broken line is misfired in any cylinder of the engine 22. Shows the situation at times.

  Subsequently, the wave height WHfc, which is the difference between the maximum value and the minimum value of the post-filter rotation speed FNc in the cycle in which the engine 22 rotates twice, is calculated (step S130), and the calculated wave height WHfc is compared with the threshold value WHref (step S130). S140) When the wave height WHfc is larger than the threshold value WHref, it is determined that any cylinder of the engine 22 has misfired (step S150), and the misfire determination process is terminated. Here, the threshold value WHref is set as a value larger than the wave height WHfc when any cylinder of the engine 22 is not misfiring and smaller than the wave height WHfc when any cylinder of the engine 22 is misfiring. It can be obtained by experiments. While the rotational fluctuation of the crankshaft 26 of the engine 22 (the fluctuation of the required rotation time T30 of 30 degrees) is due to the influence of torque fluctuation and the influence of resonance, the rotational fluctuation of the carrier 34 on the rear stage side of the damper 28 is Since this is mainly due to the effect of twisting by the damper 28, there is a low possibility that a plurality of effects will be emphasized or canceled. Therefore, by determining the misfire of the engine 22 using the wave height WHfc of the post-filter rotation speed FNc, even if it is difficult to accurately detect the misfire of the engine 22 at the 30-degree rotation time T30 described above, the engine 22 Can be determined more accurately. When the wave height WHfc of the post-filter rotation speed FNc is equal to or less than the threshold value WHref, it is determined that no cylinder of the engine 22 has misfired, and the misfire determination process is terminated.

  According to the misfire determination device for an internal combustion engine mounted on the hybrid vehicle 20 of the embodiment described above, the resonance frequency based on the twist of the damper 28 with respect to the rotational speed Nc of the carrier 34 as the rotational speed of the rear stage of the damper 28. A band-pass filter that extracts components is applied to calculate a post-filter rotation speed FNc, and misfire of the engine 22 is determined based on the calculated wave height WHfc of the post-filter rotation speed FNc. Even when it is difficult to accurately determine the misfire of the engine 22 based on (the fluctuation of the 30-degree rotation required time T30), the misfire of the engine 22 can be determined more accurately.

  In the misfire determination device for an internal combustion engine mounted on the hybrid vehicle 20 of the embodiment, the misfire of the engine 22 is determined using the 30-degree required rotation time T30 and the wave height WHfc of the post-filter rotation speed FNc. The misfire of the engine 22 may be determined using only the wave height WHfc of the rotational speed FNc.

  In the misfire determination device for an internal combustion engine mounted on the hybrid vehicle 20 of the embodiment, in addition to determining misfire of the engine 22 using the wave height WHfc of the post-filter rotation speed FNc, the engine using the 30-degree rotation required time T30 is used. However, it is not limited to determining the misfire of the engine 22 using the 30 degree rotation required time T30 as it is. For example, the 30 degree rotation required time T30 and the required 30 degree rotation before 360 degrees are required. It is good also as what determines the misfire of the engine 22 using the value based on 30 degree | times rotation required time T30, such as a difference with time T30. Moreover, it is good also as what determines the misfire of the engine 22 using the rotation speed Ne of the engine 22, etc. instead of 30 degree rotation required time T30.

  In the misfire determination apparatus for an internal combustion engine mounted on the hybrid vehicle 20 of the embodiment, the wave height of the post-filter rotation speed FNc (difference between the maximum value and the minimum value of the cycle at which the engine 22 rotates twice) WHfc is used to misfire the engine 22. However, instead of this, misfire of the engine 22 may be determined using the wave height WHc of the rotation speed Nc of the carrier 34. Further, it is not limited to the wave height WHc of the rotation speed Nc of the carrier 34 or the wave height WHfc of the post-filter rotation speed FNc, and the misfire of the engine 22 is determined using the fluctuation amount of the rotation speed Nc of the carrier 34 or the post-filter rotation speed FNc. Any configuration may be used, for example, the misfire of the engine 22 may be determined using the rotation speed Nc of the carrier 34, the amplitude of the post-filter rotation speed FNc, or the like. Here, as the amplitude, a value that is half of the wave height can be used, or a difference between the maximum value of the cycle in which the engine 22 rotates twice and the average value thereof can be used.

  In the internal combustion engine misfire determination apparatus mounted on the hybrid vehicle 20 of the embodiment, the rotation speed Nc of the carrier 34 is calculated from the rotation speeds Nm1 and Nm2 of the motors MG1 and MG2, but a rotation speed sensor is provided on the carrier shaft 34a. The rotational speed of the carrier 34 may be detected by directly detecting the rotational speed of the carrier shaft 34a.

  In the misfire determination device for an internal combustion engine mounted on the hybrid vehicle 20 of the embodiment, the misfire of any cylinder of the 6-cylinder engine 22 is determined. However, the misfire of any cylinder of the 8-cylinder engine is determined. Any number of cylinders may be used as long as it can determine misfire of any cylinder of a multi-cylinder engine, such as to determine misfire of any cylinder of a four-cylinder engine. .

  In the misfire determination device for an internal combustion engine mounted on the hybrid vehicle 20 of the embodiment, the misfire determination of the engine 22 in the configuration in which the motor MG2 is connected to the ring gear shaft 32a via the reduction gear 35 is performed. Alternatively, misfire determination of the engine 22 in a configuration in which the motor MG2 is connected to the ring gear shaft 32a via a transmission may be performed. The determination of misfire of the engine 22 in a configuration in which the motor MG2 is directly connected to the ring gear shaft 32a without using the reduction gear 35 or the transmission may be performed.

  In the misfire determination apparatus for an internal combustion engine mounted on the hybrid vehicle 20 of the embodiment, the ring gear shaft 32a is connected to the crankshaft 26 of the engine 22 via a damper 28 as a torsion element and the rotation shaft of the motor MG1 or the drive shaft. In the vehicle including the power distribution and integration mechanism 30 connected to the motor and the motor MG2 connected to the ring gear shaft 32a via the reduction gear 35, the misfire of the engine 22 is determined. Therefore, as illustrated in the hybrid vehicle 120 of the modified example of FIG. 9, the power of the motor MG2 is transmitted to the axle (drive wheel 63a) to which the ring gear shaft 32a is connected. , 63b are connected to an axle (wheels 64a, 64 in FIG. 9). 10 may be used to determine misfire of the engine 22, or as illustrated in the hybrid vehicle 220 of the modified example of FIG. 10, the damper 22 is connected to the crankshaft 26 of the engine 22 via the damper 28. It has an inner rotor 232 connected and an outer rotor 234 connected to a drive shaft that outputs power to the drive wheels 63a and 63b, and transmits a part of the power of the engine 22 to the drive shaft and uses the remaining power as electric power. It is good also as what determines the misfire of the engine 22 of what is provided with the counter-rotor electric motor 230 converted into. In this case, the motor MG2 may be connected to the axle side via the reduction gear 35 or the transmission, or may be connected to the axle side without passing through the reduction gear 35 or the transmission.

  Although the embodiment has been described as the misfire determination device for an internal combustion engine mounted on the hybrid vehicle 20, the present invention may be applied to a misfire determination device for an internal combustion engine mounted on a vehicle that does not include a motor or generator for traveling. Good. Further, the present invention may be applied to a misfire determination device for an internal combustion engine mounted on a moving body such as a vehicle other than an automobile, a ship, or an aircraft, or may be applied to a misfire determination device for an internal combustion engine incorporated in a facility that does not move. It doesn't matter. Moreover, it is good also as a form of the misfire determination method of an internal combustion engine instead of the form of the misfire determination apparatus of an internal combustion engine or the vehicle which mounts this.

  The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problems will be described. In the embodiment, rotational position detection sensors 43 and 44 for detecting the rotational positions of the rotors of the motors MG1 and MG2, and the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 are calculated based on signals from the rotational position detection sensors 43 and 44. In FIG. 5, the rotational speed Nc of the carrier 34 is calculated as the rotational speed of the rear carrier shaft 34a (corresponding to the rear shaft) of the damper 28 based on the motor ECU 40 to be calculated and the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2. The hybrid electronic control unit 70 that executes the carrier rotational speed calculation process corresponds to the “rear-stage shaft rotational speed detection means”, and the damper 28 has a rotational speed Nc as the rotational speed on the rear stage side of the damper 28. A band-pass filter that extracts the frequency component of resonance based on torsion is applied to calculate the post-filter rotation speed FNc, and the calculated frequency Engine ECU24 for executing the processing of steps S120~S150 misfire determination process of Figure 3 determines the misfire of the engine 22 based on the wave height WHfc of data after the rotation speed FNc corresponds to "misfire determining means". The crank position sensor 140 that detects the crank position (crank angle CA) that is the rotational position of the crankshaft 26 corresponds to “rotational position detecting means”, and the crankshaft 26 rotates 30 degrees based on the crank angle CA. The engine ECU 24 that executes the T30 calculation process of FIG. 4 for calculating the 30-degree rotation required time T30 as the time required for the operation corresponds to “unit rotation angle rotation required time calculation means”. Further, the engine 22 corresponds to an “internal combustion engine”, and the motor MG2 output to the rear carrier shaft 34a side of the damper 28, that is, to the rear ring gear shaft 32a via the reduction gear 35 corresponds to an “electric motor”. The power distribution integration mechanism 30 connected to the carrier shaft 34a at the rear stage of the damper 28 and the ring gear shaft 32a on the axle side, and the motor MG1 connected to the sun gear 31 of the power distribution integration mechanism 30 are “electric power input / output means”. It corresponds to.

  Here, as the “rear shaft rotational speed detection means”, the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 are determined based on signals from rotational position detection sensors 43 and 44 that detect the rotational positions of the rotors of the motors MG1 and MG2. The calculation is limited to the calculation of the rotation speed Nc of the carrier 34 as the rotation speed of the rear carrier shaft 34a (corresponding to the rear shaft) of the damper 28 based on the calculated rotation speeds Nm1 and Nm2 of the motors MG1 and MG2. Instead of detecting the rotation speed of the rear shaft, which is the rotation speed of the rear shaft, such as a rotation speed sensor mounted on the carrier shaft 34a and directly detecting the rotation speed of the carrier shaft 34a. Any object can be used. As the “misfire determination means”, a band-pass filter that extracts a frequency component of resonance based on the twist of the damper 28 is applied to the rotation speed Nc of the carrier 34 as the rotation speed of the rear stage of the damper 28, and the post-filter rotation speed The FNc is calculated and not limited to determining the misfire of the engine 22 based on the calculated wave height WHfc of the post-filter rotation speed FNc. The misfire of the engine 22 is determined based on the wave height WHc of the rotation speed Nc of the carrier 34. Or the determination of misfire of the engine 22 using the amplitude of the post-filter rotation speed FNc and the rotation speed Nc of the carrier 34, or 30 degree rotation required in addition to the wave height WHfc of the post-filter rotation speed FNc For example, the misfire of the engine 22 is determined using a value based on the time T30 or the required rotation time T30. As long as it determines the misfire of the internal combustion engine based on the variation amount of the subsequent shaft associated rotation speed is a rotation speed associated with the subsequent axis variation amount of the rotational speed or after shaft rotational speed may be any ones. The “rotational position detecting means” is not limited to the crank position sensor 140 that detects the crank position (crank angle CA) that is the rotational position of the crankshaft 26, but detects the rotational position of the output shaft of the internal combustion engine. Any object can be used. The "unit rotation angle rotation required time calculation means" is not limited to the one that calculates the 30 degree rotation required time T30 as the time required for the crankshaft 26 to rotate 30 degrees based on the crank angle CA. Instead, any unit that calculates the unit rotation angle rotation time, which is the time required for the output shaft to rotate by a predetermined unit rotation angle based on the rotation position, may be used. The “internal combustion engine” is not limited to a 6-cylinder internal combustion engine that outputs power using a hydrocarbon-based fuel such as gasoline or light oil, and an 8-cylinder or 4-cylinder engine is used, and the fuel is also hydrogen. Any type of internal combustion engine may be used. The “electric motor” is not limited to the motor MG2 that is output to the rear carrier shaft 34a side of the damper 28, that is, the rear ring gear shaft 32a via the reduction gear 35, and the rear stage that is subsequent to the twist element. Any device that can output power to the shaft side may be used. As the “power / power input / output means”, any means may be used as long as it is connected to the rear shaft and the axle side and inputs / outputs power to / from the rear shaft and the axle side with input / output of electric power and power. Absent. The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problem is the same as that of the embodiment described in the column of means for solving the problem. It is an example for specifically explaining the best mode for doing so, and does not limit the elements of the invention described in the column of means for solving the problem. 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.

  INDUSTRIAL APPLICABILITY The present invention can be used in a misfire determination device for an internal combustion engine, a vehicle manufacturing industry including the same, and the like.

1 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 20 equipped with an internal combustion engine misfire determination 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 misfire determination processing executed by an engine ECU 24. It is a flowchart which shows an example of the T30 calculation process performed by engine ECU24. 5 is a flowchart showing an example of a carrier rotation speed calculation process executed by the hybrid electronic control unit 70. It is explanatory drawing which shows an example of the time change of 30 degree | times rotation required time T30 and crank angle CA when one cylinder of the engine 22 has misfired. It is explanatory drawing which shows an example of a band pass filter. It is explanatory drawing which shows an example of the mode of the time change of the rotation speed Nc of the carrier 34, the rotation speed FNc after filter, and the crank angle CA. 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, 34a
Carrier shaft, 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 ROM, 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, 144 cam position sensor, 146 throttle valve position sensor, 148 air flow meter 149 Temperature sensor, 150 variable valve timing mechanism, 230 pair rotor motor, 232 inner rotor, 234 outer rotor, MG1, MG2 motor.

Claims (7)

A misfire determination device for determining misfire of a multi-cylinder internal combustion engine in which an output shaft is connected to a rear stage shaft via a torsion element,
A rear shaft rotational speed detection means for detecting a rear shaft rotational speed which is the rotational speed of the rear shaft;
The filter processing for detecting a frequency that is attenuated to a greater extent than the resonance frequency in a band other than the resonance frequency is set to a resonance frequency based on the torsion of the torsion element at a frequency of once per two rotations of the internal combustion engine. Misfire determination means for calculating the post-filter rotation speed by applying to the rear-stage shaft rotation speed, and determining the misfire of the internal combustion engine based on the calculated fluctuation amount of the post-filter rotation speed ;
A misfire determination apparatus for an internal combustion engine. The misfire determining means, the detected misfire determination device for processing a means for performing Claim 1 internal combustion engine according using a band-pass filter as the filter processing on the subsequent shaft rotational speed. A misfire determination device for an internal combustion engine according to claim 1 or 2 ,
Rotational position detecting means for detecting the rotational position of the output shaft of the internal combustion engine;
Unit rotation angle rotation required time calculating means for calculating a unit rotation angle rotation required time which is a time required for the output shaft to rotate by a predetermined unit rotation angle based on the detected rotation position;
With
The misfire determination means determines the misfire of the internal combustion engine based on the fluctuation amount of the post-filter rotation speed and determines the misfire of the internal combustion engine based on the calculated fluctuation of the unit rotation angle rotation time. Is,
A misfire determination device for an internal combustion engine. A multi-cylinder internal combustion engine whose output shaft is connected to the rear shaft of the rear stage via a torsion element;
The misfire determination device for an internal combustion engine according to any one of claims 1 to 3 , wherein the misfire determination of the internal combustion engine is determined.
A vehicle comprising: The vehicle according to claim 4 ,
An electric motor capable of outputting power to the rear shaft side downstream of the twist element;
The latter-stage shaft rotation speed detection means also serves as a means for detecting the motor rotation speed, which is the rotation speed of the electric motor, and detects the latter-stage shaft rotation speed by converting the detected motor rotation speed. ,
vehicle. The vehicle according to claim 4 or 5 , wherein
Power power input / output means connected to the rear shaft and the axle side, and for inputting and outputting power to the rear shaft and the axle side with input and output of electric power and power,
The electric motor is connected to the axle side so that power can be output,
The latter-stage shaft rotation speed detection means also serves as a means for detecting the drive state of the electric power drive input / output means, and calculates the latter-stage shaft rotation speed by calculation based on the detected motor rotation speed and the detected drive state. Is a means to detect,
vehicle. A misfire determination method for an internal combustion engine for determining misfire of a multi-cylinder internal combustion engine in which an output shaft is connected to a rear stage shaft through a torsion element,
A filter process for attenuating the frequency of the internal combustion engine once every two rotations as a resonance frequency based on the torsion of the torsion element is greatly reduced compared to the resonance frequency in a band other than the resonance frequency. Performing post-filter rotation speed by applying to the rear shaft rotation speed, which is the rotation speed, and determining misfire of the internal combustion engine based on the calculated fluctuation amount of the post-filter rotation speed ;
A misfire determination method for an internal combustion engine.

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