JP2014047693A - Control device for vehicle driving device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device for a vehicle driving device which includes a motor for driving an internal combustion engine, capable of reliably executing failure diagnosis and/or learning processing relating to sensors or accessory devices mounted on the engine.SOLUTION: When predetermined executing conditions are established during decelerating travel or cruising travel of a vehicle, fuel cut monitoring using a generator 62 for driving an engine 1 is performed and failure diagnosis processing of the sensors mounted on the engine 1 and/or the accessory devices for the engine 1 and/or learning processing of the operation characteristics are executed during the fuel cut monitoring. During the fuel cut monitoring, the speed of the engine 1 using the generator 62 and the flow amount of intake air in the engine 1 are controlled to be values adequate to the failure diagnosis processing and/or the learning processing to be executed.

Description

  The present invention relates to a control device for a vehicle drive device including an internal combustion engine and an electric motor, and more particularly, to a control device that executes failure diagnosis and / or learning processing when a fuel cut operation for stopping fuel supply to the engine is performed.

  Patent Document 1 discloses a control device for a vehicle drive device that includes an internal combustion engine that includes an intake valve operation phase variable mechanism that changes the operation phase of the intake valve, and an electric motor that can drive the engine. According to this control device, when a predetermined engine stop condition is satisfied, fuel cut motoring for rotating the engine at a predetermined number of revolutions by an electric motor in a state where fuel supply to the engine is stopped is performed for a predetermined time. During the fuel cut motoring, the operation phase of the intake valve is controlled to the most retarded phase (maximum retard angle phase) within a changeable range. Thereby, good startability can be obtained at the next engine start.

  Also, for example, as disclosed in Patent Documents 2 and 3, failure diagnosis and learning of operating characteristics of sensors and auxiliary devices attached to an internal combustion engine, such as air-fuel ratio sensors (oxygen concentration sensors), crank angle sensors, exhaust gas recirculation devices, etc. It is well known that processing is performed during engine fuel cut operations.

JP 2008-190495 A Japanese Patent Laid-Open No. 7-180615 JP 2008-111354 A

  According to the device disclosed in Patent Document 1, it is possible to learn the operating characteristics of the intake valve operating phase variable mechanism, but the fuel cut motoring is performed immediately before the engine is stopped, and the predetermined rotational speed is set to idling. Since the engine speed is as low as the engine speed and the scavenging of the engine is insufficient, failure diagnosis or learning processing that is normally performed in fuel cut operation cannot be performed. In addition, when the cruise travel continues for a long time on an expressway or the like, there is a problem that the frequency of executing the failure diagnosis or the learning process decreases.

  The present invention has been made paying attention to this point, and in a vehicle drive device including an electric motor capable of driving an engine, fault diagnosis and / or learning processing related to a sensor or an auxiliary device attached to the engine is surely performed. An object of the present invention is to provide a control device that can be executed.

  In order to achieve the above object, a first aspect of the present invention provides a control device for a vehicle drive device including an internal combustion engine (1) for driving a vehicle and an electric motor (62) provided to drive the engine. Diagnosis learning processing including at least one failure diagnosis of the sensors (11, 15) and the auxiliary device (40) mounted on the engine and / or learning processing for learning at least one operation characteristic of the sensor and the auxiliary device. Diagnostic learning means that is executed when the fuel supply to the engine (1) is stopped and the engine is rotating, and when a predetermined execution condition is established while the vehicle is running, Motor diagnosis control means for stopping fuel supply and executing fuel cut motoring for driving the engine by the electric motor (62). And executes the diagnostic learning process during the fuel cut motoring.

  According to a second aspect of the present invention, in the control device for a vehicle drive device according to the first aspect, the control device includes a suction air flow rate control means for controlling a suction air flow rate (GAIR) of the engine, and the motoring control means includes: At least one of the engine speed (NE) and the intake air flow rate (GAIR) during execution of the fuel cut motoring is controlled to a value suitable for a diagnosis learning process executed by the diagnosis learning means.

  According to a third aspect of the present invention, in the control device for a vehicle drive device according to the first or second aspect, the motoring control unit is configured to perform the fuel learning when a diagnostic learning process to be executed by the diagnostic learning unit is completed. When cut motoring is finished and the fuel cut motoring execution time (TFCM) reaches a predetermined upper limit time (TFCMMAX) before the completion of the diagnostic learning process, the fuel cut motoring is performed at that time. It is characterized by terminating.

  According to a fourth aspect of the present invention, in the control device for a vehicle drive device according to any one of the first to third aspects, the motoring control means has completed a diagnostic learning process to be executed by the diagnostic learning means. After that, the fuel cut motoring is not executed during the current operation period from when the ignition switch is turned off until the engine stops.

  According to a fifth aspect of the present invention, in the control device for a vehicle drive device according to any one of the first to fourth aspects, the auxiliary device is a valve that changes an operating phase (CAIN) of an intake valve of the engine. The diagnosis learning means includes a variable operation characteristic mechanism, and the diagnosis learning means learns the latest retardation phase control amount that is a control amount when controlling the operation phase (CAIN) of the intake valve to the most retarded angle phase (CAINMIN). The angular phase control learning process is executed after the other diagnostic learning process is completed.

  According to a sixth aspect of the present invention, in the control device for a vehicle drive device according to any one of the first to fifth aspects, the predetermined execution condition is that the traveling speed of the vehicle is higher than a predetermined speed and the diagnosis is performed. A condition is included in which the cruise traveling state of the vehicle continues for a predetermined time or longer in a state where the execution condition of the learning process is satisfied.

  According to the first aspect of the present invention, when a predetermined execution condition is satisfied while the vehicle is running, the fuel cut motoring that stops the fuel supply to the engine and drives the engine by the electric motor is executed and attached to the engine. Diagnosis learning processing of the sensor and / or the accessory device is executed during fuel cut motoring. Therefore, failure diagnosis and / or learning processing can be executed not only during normal vehicle deceleration traveling but also during cruise traveling, for example, and the diagnostic learning processing can be reliably performed.

  According to the second aspect of the present invention, at least one of the engine speed and the intake air flow rate during execution of fuel cut motoring is controlled to a value suitable for the diagnostic learning process to be executed. Can be increased.

  According to the third aspect of the present invention, when the fuel cut motoring ends when the diagnostic learning process to be executed is completed, and the execution period of the fuel cut motoring reaches a predetermined upper limit time before the completion time Since the fuel cut motoring ends at that time, it is possible to prevent the fuel cut motoring execution time from becoming longer than necessary. As a result, it is possible to suppress power consumption for driving the engine by the electric motor and improve fuel efficiency.

  According to the fourth aspect of the present invention, after the diagnosis learning process to be executed is completed, the fuel cut motoring is not executed during the current operation period from when the ignition switch is turned off until the engine stops. Is done. Since it is sufficient to execute the diagnosis learning process once in one operation period (period from the ignition switch ON time to the OFF time), the fuel cut motoring is not performed after the diagnosis learning process to be executed is completed. As a result, power consumption required for driving the electric motor can be suppressed.

  According to the fifth aspect of the present invention, the most retarded angle phase control learning process for learning the most retarded angle phase control amount, which is a control amount when controlling the operation phase of the intake valve to the most retarded angle phase, It is executed after the diagnosis learning process is completed. In the most retarded angle phase control learning process, it is necessary to actually shift the intake valve operating phase to the most retarded angle phase, but in the most retarded angle phase, a part of the air sucked into the cylinder is returned to the intake passage, The scavenging condition of the engine deteriorates. Therefore, the intake valve operating phase is set to a relatively advanced phase, the diagnostic learning process to be executed in a good scavenging state of the engine is executed first, and then the most retarded phase control learning process is executed. As a result, the change in the intake valve operating phase can be minimized and the diagnosis learning process can be completed quickly.

  According to the sixth aspect of the present invention, the predetermined execution condition for the fuel cut motoring is a pre-condition condition in which the vehicle traveling speed is higher than the predetermined speed and the execution condition for the diagnostic learning process is satisfied. Including a condition that the cruise running state of the vehicle continues for a predetermined time or more. In the cruise driving state, the vehicle traveling speed is stable, the predetermined execution condition satisfaction state is more likely to continue more stably than the vehicle deceleration state, and the cruise traveling state in which the precondition is satisfied continues for a predetermined time or more. Therefore, the fuel cut motoring can be executed in a more stable vehicle traveling state, and the diagnosis learning process can be completed with certainty.

It is a figure which shows the structure of the vehicle drive device concerning one Embodiment of this invention. It is a figure for demonstrating the operation mode of the vehicle drive device shown in FIG. It is a figure which shows the structure of the control system of the internal combustion engine shown in FIG. 1, a motor, and a generator. It is a figure which shows the lift curve of an intake valve and an exhaust valve. It is a flowchart of the process which determines the execution conditions of fuel cut motoring. It is a time chart for demonstrating the example of control operation by the process of FIG. It is a time chart which shows transition of the intake air flow rate and engine speed during fuel cut motoring.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram showing a configuration of a vehicle drive device according to an embodiment of the present invention. The vehicle drive device includes an internal combustion engine (hereinafter referred to as “engine”) 1 and a motor 61 as drive sources, A generator 62 driven by the electric power of the high-voltage battery 66 and a driving force transmission mechanism 54 that transmits the driving force of the engine 1 and the motor 61 to the driving wheels 56 are provided. The output shaft 51 of the engine 1 is connected to the driving force transmission mechanism 54 via the clutch 52 and the driving shaft 53, and the output shaft 65 of the motor 61 is directly connected to the driving force transmission mechanism 54. The motor 61 operates as a generator when performing a regenerative operation. The driving force transmission mechanism 54 includes a differential gear mechanism.

  The output shaft 51 of the engine 1 is connected to a generator 62 via a gear pair 57, and the generator 62 generates power by the driving force of the engine 1 and performs fuel cut motoring, which will be described later. It operates as a motor that drives

  The motor 61 and the generator 62 are electrically connected to power driving units (hereinafter referred to as “PDU”) 63 and 64, respectively. The PDU 63 is connected to the PDU 64 and the high voltage battery 66. The PDUs 63 and 64 are connected to a motor control electronic control unit (hereinafter referred to as “MOT-ECU”) 70, and control the operation of the motor 61 and the generator 62, respectively, and charge the high voltage battery 66. Control the discharge.

  FIG. 2 is a diagram for explaining an operation mode of the vehicle drive device shown in FIG. 1. Since the components shown in FIG. 2 are the same as those in FIG. 1, some of the reference numerals are omitted. Note that the broken line shown in FIG. 2 indicates a transmission path of electric power or driving force.

  FIG. 2A shows a first operation mode in which the vehicle travels with the output of the motor 61 driven by the electric power supplied from the high voltage battery 66. In the first operation mode, the engine 1 is stopped and the clutch 52 is released (not fastened).

  FIG. 2B shows a second operation mode in which the clutch 52 is disengaged, the engine 1 is operated to generate power by the generator 62, and the vehicle travels with the output of the motor 61 driven by the generated power. In the second operation mode, when the power generated by the generator 62 is larger than the power consumption of the motor 61, the high-voltage battery 66 is charged with surplus power, while the power generated by the generator 62 is smaller than the power consumption of the motor 61. Sometimes, the insufficient power is compensated by the discharge of the high voltage battery 66.

  FIG. 2C shows a third operation mode in which the vehicle travels mainly by the output of the engine 1. In the third operation mode, the clutch 52 is engaged and the output of the engine 1 is input to the driving force transmission mechanism 54 and transmitted to the driving wheels 56. In the third operation mode, surplus torque or insufficient torque is generated due to increase / decrease in engine load. Therefore, when surplus torque is generated, the motor 61 is operated as a generator to charge the high voltage battery 66, while the insufficient torque When this occurs, the engine output is assisted by the output of the motor 61.

  FIG. 2D shows a fourth operation mode in which the motor 61 is driven by the electric power supplied from the high voltage battery 66 and the generator 62 performs fuel cut motoring of the engine 1. In the fourth operation mode, when the vehicle is decelerated, the motor 61 is operated as a generator, the drive power of the generator 62 is supplied, and the high voltage battery 66 is charged. The fourth operation mode is an operation mode for performing failure diagnosis and operation characteristic learning processing of auxiliary devices such as a sensor and an exhaust gas recirculation device mounted on the engine 1 as will be described later, and ends in a relatively short time.

  FIG. 3 is a diagram showing the configuration of the control system of the engine 1 and the motor 61 / generator 62. The engine 1 is controlled by an engine control electronic control unit (hereinafter referred to as “ENG-ECU”) 5, and the motor 61 / power generation The machine 62 is controlled by the MOT-ECU 70 via the PDUs 63 and 64. The ENG-ECU 5, the MOT-ECU 70, and the drive system control electronic control unit (PT-ECU, not shown) are connected to each other via the bus 100 and transmit necessary information to each other. The clutch 52 shown in FIG. 1 is controlled to be engaged / released by the PT-ECU.

  The engine 1 includes a first valve operating characteristic variable mechanism 41 that switches a valve lift amount and an opening angle of an intake valve (not shown) in two stages, and a second valve operating characteristic variable mechanism that continuously changes the operating phase of the intake valve. 42 is provided with a variable valve operating characteristic device 40.

  A throttle valve 3 is arranged in the intake passage 2 of the engine 1. A throttle valve driving device 4 is attached to the throttle valve 3, and the throttle valve driving device 4 is connected to the ENG-ECU 5. The throttle valve driving device 4 includes a throttle actuator that drives the throttle valve 3 and a throttle valve opening sensor, and a detection signal from the throttle valve opening sensor is supplied to the ENG-ECU 5 and driven from the ENG-ECU 5. The throttle valve opening TH is controlled to the target opening THCMD by the signal.

  The fuel injection valve 6 is provided for each cylinder between the engine 1 and the throttle valve 3 and slightly upstream of the intake valve (not shown) in the intake passage 2, and each injection valve is connected to a fuel pump (not shown). At the same time, it is electrically connected to the ENG-ECU 5, and the valve opening time and valve opening timing of the fuel injection valve 6 are controlled by a signal from the ECU 5.

  An intake air flow rate sensor 7 for detecting an intake air flow rate GAIR [g / sec] is provided upstream of the throttle valve 3. An intake pressure sensor 8 for detecting the intake pressure PBA and an intake air temperature sensor 9 for detecting the intake air temperature TA are provided on the downstream side of the throttle valve 3. Detection signals from these sensors are supplied to the ENG-ECU 5. A cooling water temperature sensor 10 for detecting the engine cooling water temperature TW is mounted on the main body of the engine 1, and the detection signal is supplied to the ENG-ECU 5.

  The ENG-ECU 5 detects a rotation angle of a crank angle position sensor 11 that detects the rotation angle of the crank shaft of the engine 1 and a rotation angle of a cam shaft (not shown) to which a cam that drives the intake valve of the engine 1 is fixed. A cam angle position sensor 12 is connected, and a signal corresponding to the rotation angle of the crankshaft and the rotation angle of the camshaft is supplied to the ENG-ECU 5. The crank angle position sensor 11 generates one pulse (hereinafter referred to as “CRK pulse”) for every predetermined crank angle cycle (for example, a cycle of 6 degrees) and a pulse for specifying a predetermined angular position of the crankshaft. The cam angle position sensor 12 generates a cam pulse at a predetermined crank angle position of a specific cylinder of the engine 1 and generates a TDC pulse at the top dead center (TDC) at the start of the intake stroke of each cylinder. These pulses are used for various timing controls such as fuel injection timing and ignition timing, and detection of engine speed (engine speed) NE. The actual operating phase (intake valve operating phase) CAIN of the camshaft can be detected from the relative relationship between the cam pulse output from the cam angle position sensor 12 and the CRK pulse output from the crank angle position sensor 11. .

  The exhaust passage 13 is provided with a proportional oxygen concentration sensor 15 (hereinafter referred to as “LAF sensor 15”), a three-way catalyst 14 as an exhaust purification device, and a binary oxygen concentration sensor (hereinafter referred to as “O2 sensor”) 16. The detection signals of the LAF sensor 15 and the O2 sensor 16 are supplied to the ENG-ECU 5 and applied to the air-fuel ratio control of the air-fuel mixture combusted in the engine 1.

  The ENG-ECU 5 is connected to an accelerator sensor 21 for detecting an accelerator pedal depression amount (hereinafter referred to as “accelerator pedal operation amount”) AP of a vehicle driven by the engine 1, and the detection signal is sent to the ENG-ECU 5. Supplied. The throttle valve 3 is opened and closed by a throttle valve driving device 4 and the throttle valve opening TH is controlled by the ENG-ECU 5 in accordance with the accelerator pedal operation amount AP. In the present embodiment, the traveling speed (vehicle speed) VP of the vehicle is calculated by multiplying the rotational speed of the motor 61 by a predetermined coefficient, but it may be detected by providing a normal vehicle speed sensor.

  The valve operating characteristic variable device 40 continuously changes the operating phase of the intake valve and the first valve operating characteristic variable mechanism 41 that switches the lift amount and the opening angle of the intake valve between the first operating characteristic and the second operating characteristic. A second valve operating characteristic variable mechanism 42, a hydraulic control mechanism 43 for driving the first valve operating characteristic variable mechanism 41, and an electric actuator 44 for driving the second valve operating characteristic variable mechanism 42 are provided. . The operations of the hydraulic control mechanism 43 and the electric actuator 44 are controlled by the ENG-ECU 5.

According to the variable valve operation characteristic device 40, the intake valve changes with the change in the cam operation phase CAIN, centering on the first operation characteristic indicated by the solid line L 1 in FIG. 4 and the second operation characteristic indicated by the solid line L 2. It is driven at a phase between the most advanced angle phase indicated by broken lines L3 and L4 and the most retarded angle phase indicated by alternate long and short dash lines L5 and L6. The exhaust valve is driven with a constant operating characteristic indicated by a solid line L7. As apparent from FIG. 4, in this embodiment, the closing timing CAIVC of the intake valve is set to be after the start of the compression stroke, and the Atkinson cycle operation is performed.
Although not shown, the engine 1 is provided with an exhaust gas recirculation mechanism and an evaporative fuel processing device that are well-known as incidental devices.

The ENG-ECU 5 forms an input signal waveform from various sensors, corrects a voltage level to a predetermined level, converts an analog signal value into a digital signal value, a central processing unit (hereinafter “ CPU ”), a storage circuit for storing various calculation programs executed by the CPU, calculation results, and the like, an output circuit for supplying a drive signal to the fuel injection valve 6, the valve operation characteristic variable device 40, and the like.
The MOT-ECU 70 controls the operation of the motor 61 and the generator 62 via the PDUs 63 and 64 according to the traveling state of the vehicle and the operating state of the engine 1.

  In the present embodiment, the vehicle drive device is operated in the fourth operation mode as described above while the vehicle is running, and a predetermined failure diagnosis process and a learning process (hereinafter referred to as “predetermined diagnosis learning process”) are executed. In the following description, the fuel cut motoring executed in the fourth operation mode is referred to as “FC motoring”.

FIG. 5 is a flowchart of a process for determining the FC motoring execution condition. This process is executed in the ENG-ECU 5 at predetermined intervals.
In step S11, it is determined whether or not the FC motoring execution condition flag FFCMMCND is “1”. When all of the following conditions A1) to A4) are satisfied, it is determined that the FC motoring execution condition is satisfied, and the FC motoring execution condition flag FFCMMCND is set to “1”.

A1) The vehicle speed VP is higher than the predetermined vehicle speed VPTH.
A2) The engine cooling water temperature TW is higher than the predetermined water temperature TWTH.
A3) The shift lever position of the transmission is in the D range or B range (drive range).
A4) The temperature increase control of the three-way catalyst 14 is not executed.
The predetermined vehicle speed VPTH is set to a predetermined upper vehicle speed VPTHH and a predetermined lower vehicle speed VPTH, as determined with hysteresis characteristics in the present embodiment, and the predetermined upper vehicle speed VPTH is set to, for example, 70 km / h. The predetermined lower vehicle speed VPTHL is set to, for example, 50 km / h.

  If the answer to step S11 is affirmative (YES), it is determined whether or not a diagnostic learning execution condition flag FOBDLCND is “1” (step S12). When all of the following conditions B1) to B7) are satisfied, it is determined that the diagnosis learning execution condition is satisfied, and the diagnosis learning execution condition flag FOBDLCND is set to “1”.

B1) The intake air temperature TA is higher than the predetermined intake air temperature TATH.
B2) The elapsed time from the completion of start of the engine 1 exceeds a predetermined time.
B3) The output voltage VBAT12 (on the average, about 12V) of a low-voltage battery (not shown, a battery that supplies power to a sensor or ECU) is higher than a predetermined lower limit voltage.
B4) Activation of a sensor that is a target of the predetermined diagnosis learning process or a sensor used in the predetermined diagnosis learning process is completed.
B5) Execution of the predetermined diagnosis learning process is permitted.
B6) The predetermined diagnosis learning process is not completed.
B7) The execution of the predetermined diagnosis learning process is not suspended.

  If the answer to step S12 is affirmative (YES), it is determined whether or not an FC motoring cancel request flag FFCMCL is “0” (step S13). The FC motoring cancel request flag FFCMCL is set to “1” in step S28 when the determination result in step S27 described later is affirmative (YES).

  When the answer to any of steps S11 to S13 is negative (NO), both the FC motoring executable flag FDECCFCIRQ and the FC motoring cancel request flag FFCMCL are set to “0” (step S14), and the process proceeds to step S21. move on.

  If the answer to step S13 is affirmative (YES), the FC motoring executable flag FDECCFCIRQ is set to “1” (step S15), and whether or not the vehicle is decelerating (the vehicle speed VP is decreasing). Is determined (step S16). If the answer is negative (NO), it is determined whether or not the vehicle is traveling on a cruise (traveling state where the vehicle speed VP is substantially constant) (step S18).

  If the answer to step S18 is affirmative (YES), that is, if the vehicle is cruising, the EV interference counter CINT is counted up (step S19), and then whether or not the value of the EV interference counter CINT is equal to or greater than a predetermined threshold CINTTH. It discriminate | determines (step S20).

  In the present embodiment, during cruise traveling, the engine 1 is temporarily stopped and the operation in the first operation mode (the operation mode using only the motor 61 as a drive source) is performed, but the FC motoring executable flag FDECCFCIRQ is set. When “1” is set, the transition to the first operation mode is prohibited. The value of the EV interference counter CINT is used as a parameter indicating the prohibited period.

  If the answer to step S20 is negative (NO), the process proceeds to step S25, the FC motoring request flag FFCMREQ is set to “0”, and FC motoring is not executed. If the answer to step S20 is affirmative (YES), the process proceeds to step S22.

  On the other hand, if the answer to step S16 is affirmative (YES), that is, if the vehicle speed VP is decreasing, the value of the EV interference counter CINT is set to “0” (step S17), and the process proceeds to step S22.

  In step S22, it is determined whether or not the first diagnosis learning end flag FOBDLEND1 is “1”. The first diagnosis learning end flag FOBDLEND1 is set to “1” when the diagnosis learning process other than the most retarded phase learning process of the second valve operating characteristic variable mechanism 42 is completed. The most retarded angle learning process is a process of learning a control amount (specifically, a supply current value) supplied to the electric actuator 44 when the operation phase CAIN of the intake valve is controlled to the most retarded angle CAINMIN.

If the answer to step S22 is affirmative (YES), the intake valve operating phase CAIN is moved to the most retarded angle phase CAINMIN, that is, the most retarded angle phase learning process is started (step S23). If the answer to step S22 is negative (NO), the process immediately proceeds to step S24. In step S24, it is determined whether or not the second diagnosis learning end flag FOBDLEND2 is “1”. The second diagnosis learning end flag FOBDLEND2 is set to “1” when all the diagnosis learning processes are completed.
Initially, the answer to step S24 is negative (NO), the process proceeds to step S26, the FC motoring request flag FFCMREQ is set to “1”, and FC motoring is executed.

  In step S27, it is determined whether or not an elapsed time (FC motoring execution time) TFCM from the start time of FC motoring is equal to or longer than a predetermined upper limit time TFCMMAX. Initially, the answer to step S27 is negative (NO), and the process immediately ends. Thereafter, when the FC motoring execution time TFCM reaches the predetermined upper limit time TFCMMAX, the process proceeds from step S27 to S28, and the FC motoring cancel request flag FFCMCL is set to “1”. As a result, the FC motoring is completed even if all the diagnostic learning processes are not completed.

  If the answer to step S24 is affirmative (YES), the process proceeds to step S25, and the FC motoring is terminated. If the answer to step S18 is negative (NO), that is, if the vehicle is accelerating, the process proceeds to step S21, the value of the EV interference counter CINT is set to “0”, and the process proceeds to step S25.

  FIG. 6 is a time chart for explaining an example of the control operation by the processing of FIG. 5, and FIGS. 6A to 6F show an FC motoring executable flag FDECCFCIRQ, a fuel cut flag FFC, and FC motoring, respectively. The change of the request flag FFCMREQ, the value of the EV interference counter CINT, the engine speed NE, and the vehicle speed VP is shown.

  At time t1, the FC motoring execution condition and the diagnosis learning execution condition are satisfied, and the FC motoring executable flag FDECCFCIRQ changes from “0” to “1”. Thereafter, the cruise is started from time t2, and the EV interference counter CINT starts counting up. When the value of the EV interference counter CINT reaches the predetermined threshold value CINTTH at time t3, the FC motoring request flag FFCMREQ is set to “1”, and FC motoring is started. When all the predetermined diagnosis learning processes are completed at time t4, the diagnosis learning execution condition flag FOBDLCND is returned to “0”, the FC motoring executable flag FDECCFCIRQ is set to “0”, and FC motoring ends.

  During the period when the FC motoring executable flag FDECCFCIRQ is set to “1”, the first operation mode (operation mode in which the engine 1 is stopped and the motor 61 is used as a drive source) is prohibited. In FIG. 6 (e), the broken line that decreases from time t2 toward “0” indicates the transition of the engine speed NE when the prohibition of the first operation mode is not performed.

  In the operation example shown in FIG. 6, since the FC motoring execution time TFCM has not reached the predetermined upper limit time TFCMMAX at time t4, FC motoring ends at time t4 when all the predetermined diagnosis learning processing is completed. If the FC motoring execution time TFCM reaches the predetermined upper limit time TFCMMAX before all the predetermined diagnosis learning processes are completed, the FC motoring ends at that time. The predetermined upper limit time TFCMMAX is set by adding a slight margin time to the time required to complete all the predetermined diagnosis learning processing.

  Since the predetermined diagnosis learning process only needs to be executed once in one operation period (a period from when the ignition switch is turned on until it is turned off), all the predetermined diagnosis learning processes are completed and the diagnosis learning execution condition flag FOBDLCND is set. After it becomes “0”, it does not become “1” during the operation period, and therefore the FC motoring executable flag FDECCFCIRQ is also maintained at “0”.

  When the FC motoring execution time TFCM reaches the predetermined upper limit time TFCMMAX and FC motoring is completed before all the predetermined diagnosis learning processes are completed, the FC motoring executable flag FDECCFCIRQ is set to “1”, and then FC When the motoring request flag FFCMREQ becomes “1”, FC motoring is executed, and diagnostic learning processing that has not been completed is executed.

  FIG. 7 is a time chart showing the transition of the intake air flow rate GAIR and the engine speed NE during FC motoring. In this embodiment, the elapsed time from the start of FC motoring, that is, the FC motoring execution time TFCM is shown. Accordingly, by changing the target throttle valve opening THCMD, the intake air flow rate GAIR is controlled to the first flow rate value GAIR1 and the second flow rate value GAIR2 (FIG. 7 (a)), and the rotational speed of the generator 62 is changed. By changing the engine speed NE gradually from the first speed NE1 to the fourth speed NE4 (FIG. 7B).

  In the first diagnosis learning period TFCDL1 shown in FIG. 7, for example, the operation characteristic learning process of the crank angle position sensor 11 and the failure diagnosis process of the LAF sensor 15 are executed, and in the second diagnosis learning period TFCDL2, for example, the failure of the exhaust gas recirculation mechanism Diagnosis processing and the most retarded angle phase learning processing of the second valve operating characteristic variable mechanism 42 are executed. Note that, as described in the processing of FIG. 5, in the present embodiment, the most retarded phase learning process is executed last.

The reason why the diagnosis learning process is executed while changing the intake air flow rate GAIR and the engine speed NE as shown in FIG. 7 is as follows.
1) Operation characteristic learning process of the crank angle position sensor 11: The higher the engine speed NE, the more sampling values can be obtained in a short time and the learning accuracy can be improved, so this is executed in the first diagnosis learning period TFCDL1.
2) Failure diagnosis process of the LAF sensor 15: Since a good scavenging state is required, it is desirable that the intake air flow rate GAIR and the engine speed NE are high, and therefore, it is executed in the first diagnosis learning period TFCDL1.
3) Failure diagnosis processing of the exhaust gas recirculation mechanism: If the intake air flow rate GAIR is high, intake pulsation is likely to occur, and the diagnosis accuracy is lowered.
4) Most retarded angle learning process: It is necessary to change the intake valve operating phase CAIN to the most retarded phase, and the rotational torque of the engine acts in the direction toward the most retarded phase. Therefore, when the engine speed NE is high, the movable member is strongly abutted against the stopper that regulates the most retarded phase, and the electric actuator 44 generates a large amount of heat. Therefore, it is executed in the second diagnosis learning period TFCDL2 in which the engine speed NE is relatively low.
The engine 1 is stopped during normal operation when the diagnosis learning process is not performed. In the diagnosis learning process, the rotation of the engine 1 is maintained by motoring the generator 62. After the diagnosis learning process is completed, the engine 1 is basically operated. Stop. For this purpose, the intake air flow rate GAIR and the engine speed NE are controlled to decrease with the passage of time from the start of FC motoring (increase in FC motoring execution time TFCM).

  As described above, in the present embodiment, when a predetermined execution condition is satisfied while the vehicle is running, the fuel supply of the engine 1 is stopped and the FC motoring that drives the engine 1 by the generator 62 is executed. A failure diagnosis or operation characteristic learning process of the attached sensor and the auxiliary device is executed during FC motoring. Therefore, failure diagnosis and / or learning processing can be executed not only during normal vehicle deceleration traveling but also during cruise traveling, for example, and failure diagnosis and the like can be reliably performed.

  Further, as shown in FIG. 7, since the engine speed NE and the intake air flow rate GAIR during FC motoring are controlled to values suitable for the fault diagnosis or learning process to be executed, the accuracy of the fault diagnosis or learning process is increased. Can be increased.

  If the FC motoring execution time TFCM reaches the predetermined upper limit time TFCMMAX before all the predetermined diagnosis learning processing is completed, the FC motoring execution time is longer than necessary by terminating the FC motoring at that time. Can be prevented. As a result, power consumption of the high-voltage battery 66 can be suppressed and fuel consumption can be improved.

  Further, after the predetermined diagnosis learning process is completed, control is performed so as not to execute FC motoring during the operation period. Since it is sufficient to execute the predetermined diagnosis learning process once in one operation period, the power consumption required to drive the generator 62 is suppressed by not performing FC motoring after the completion of the predetermined diagnosis learning process. can do.

  Further, since the most retarded phase learning process of the second valve actuation characteristic variable mechanism 42 is executed after the other diagnosis learning processes are completed, the entire diagnosis learning process can be completed quickly as described below. . In the most retarded angle phase learning process, it is necessary to actually shift the intake valve operating phase CAIN to the most retarded angle phase CAINMIN, but in the most retarded angle phase CAINMIN, a part of the air taken into the cylinder is returned to the intake passage. For this reason, the scavenging state of the engine 1 is deteriorated. Therefore, the intake valve operating phase CAIN is set to a relatively advanced angle phase, the diagnostic learning process to be executed in a good scavenging state of the engine 1 is executed first, and then the most retarded angle phase learning process is executed. By doing so, the change of the intake valve operating phase CAIN can be suppressed to the minimum, and the diagnosis learning process can be completed quickly.

  In the process of FIG. 5, the FC motoring request flag FFCMREQ is set to the EV interference counter CINT when the vehicle speed VP is higher than the predetermined vehicle speed VPTH and the diagnosis learning execution condition flag FOBDLCND is set to “1”. Is set to “1” on condition that the value of the vehicle is equal to or greater than a predetermined threshold value CINTTH (FIG. 5, S11, S12, S18 to S20), that is, the cruise running state of the vehicle continues for a predetermined time or more. There is a high possibility that the vehicle speed VP is stable in the cruise traveling state and the vehicle speed VP is higher than the predetermined vehicle speed VPTH more stably than the vehicle deceleration state, and the cruise traveling state in which the precondition is satisfied is Since the condition is that it continues for a predetermined time or longer, FC motoring can be executed in a more stable vehicle running state, and the diagnostic learning process can be completed with certainty.

  In the present embodiment, the generator 62 corresponds to the “motor” recited in the claims, the exhaust gas recirculation mechanism, the evaporated fuel processing device, and the valve operating characteristic variable device 40 correspond to the auxiliary device, and the throttle valve 3 and The throttle valve driving device 4 constitutes part of the intake air flow rate control means, and the ENG-ECU 5 constitutes diagnostic learning means, part of the motoring control means, and part of intake air flow rate control means, and the MOT-ECU 70 Constitutes a part of the motoring control means.

  The present invention is not limited to the embodiment described above, and various modifications can be made. For example, in the above-described embodiment, the vehicle drive device including the engine 1 including the valve operation characteristic variable device 40 is shown. However, the present invention does not include the valve operation characteristic variable device 40 and drives a normal intake valve. The present invention is also applicable to a control device for a vehicle drive device including an internal combustion engine having a mechanism.

  In the above-described embodiment, an example in which a plurality of failure diagnosis processes and learning processes are executed during FC motoring has been shown. However, the present invention executes at least one failure diagnosis process or learning process during fuel cut operation. It is applicable to.

  Further, in the embodiment described above, both the intake air flow rate GAIR and the engine speed NE are changed as shown in FIG. 7 during FC motoring, but only one of them is changed and the other is set to a constant value. You may make it maintain.

  In the above-described execution mode, the vehicle drive device including the engine 1 that performs Atkinson cycle operation is shown. However, the present invention can also be applied to a control device for a vehicle drive device that includes an internal combustion engine that operates with normal intake valve operating characteristics. It is.

1 Internal combustion engine 3 Throttle valve (intake air flow rate control means)
4 Throttle valve drive device (intake air flow rate control means)
5 Electronic control unit for engine control (diagnosis learning means, motoring control means, intake air flow rate control means)
62 Generator (electric motor)
70 Electronic control unit for motor control (motoring control means)

Claims (6)

In a control device for a vehicle drive device comprising an internal combustion engine for driving a vehicle and an electric motor provided to drive the engine,
Supplying fuel to the engine by a diagnostic learning process including at least one failure diagnosis process of the sensor and the accessory device mounted on the engine and / or a learning process of learning at least one operation characteristic of the sensor and the accessory device Diagnostic learning means to be executed in a state where the engine is stopped and the engine is rotating,
Motoring control means for stopping fuel supply to the engine and performing fuel cut motoring for driving the engine by the electric motor when a predetermined execution condition is satisfied during traveling of the vehicle;
The control device for a vehicle drive device, wherein the diagnosis learning means executes the diagnosis learning process during execution of the fuel cut motoring. Intake air flow rate control means for controlling the intake air flow rate of the engine,
The motoring control means controls at least one of the engine speed and the intake air flow rate during execution of the fuel cut motoring to a value suitable for a diagnosis learning process executed by the diagnosis learning means. The control apparatus of the vehicle drive device of Claim 1.   The motoring control means ends the fuel cut motoring when the diagnosis learning process to be executed by the diagnosis learning means is completed, and executes the fuel cut motoring execution time before the completion of the diagnosis learning process. 3. The vehicle drive device control device according to claim 1, wherein the fuel cut motoring is terminated at the time when the predetermined upper limit time is reached. 4.   The motoring control means does not execute the fuel cut motoring during a current operation period from when the ignition switch is turned off until the engine stops after the diagnosis learning process to be executed by the diagnosis learning means is completed. The control device for a vehicle drive device according to claim 1, wherein the control device is a vehicle drive device control device. The auxiliary device includes a valve operation characteristic variable mechanism that changes an operation phase of an intake valve of the engine,
The diagnosis learning means performs a most retarded angle phase control learning process for learning a most retarded angle phase control amount, which is a control amount when the operating phase of the intake valve is controlled to the most retarded angle phase. The control device for a vehicle drive device according to any one of claims 1 to 4, wherein the control device is executed after completion.   The predetermined execution condition includes a condition that the cruise traveling state of the vehicle continues for a predetermined time or more in a state where the traveling speed of the vehicle is higher than the predetermined speed and the execution condition of the diagnosis learning process is satisfied. The control device for a vehicle drive device according to any one of claims 1 to 5, wherein:

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