JP2017165177A - Hybrid vehicle control unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately determine abnormalities of first and second clutches in a hybrid vehicle comprising: an engine connected to driving wheels through a first clutch; and an electric motor connected to the driving wheels through a second clutch in parallel with the engine.SOLUTION: A hybrid vehicle electronic control unit, or HVECU, controls a hybrid vehicle which comprises: an engine connected with front side and rear side driving wheels through a clutch C0; and a motor generator connected with the front side and rear side driving wheels through a clutch C2 in parallel with the engine. The HVECU determines abnormalities of the clutches C0, C2 on the basis of a change of the rotation speed Ne of the engine according to a torque output of the motor generator in a state that an engagement command or a release command is provided to the clutch C0 and an engagement command or a release command is provided to the clutch C2 (steps S100 - S190).SELECTED DRAWING: Figure 2

Description

  The present disclosure relates to a control apparatus for a hybrid vehicle including an engine coupled to drive wheels via a first clutch and an electric motor coupled to the drive wheels via a second clutch in parallel with the engine.

  Conventionally, as a hybrid vehicle, an engine having a starter, a motor generator, an automatic transmission unit having an input shaft, a first clutch provided between the motor generator and the input shaft of the automatic transmission unit, an engine and an automatic A device including a second clutch provided between an input shaft of a transmission unit is known (see, for example, Patent Document 1). In this vehicle, by engaging the first clutch and releasing the second clutch, the power from the motor generator is shifted by the automatic transmission unit while the engine is disconnected from the input shaft of the automatic transmission unit. Can be communicated to. Further, by engaging both the first and second clutches, the power from at least one of the engine and the motor generator can be shifted by the automatic transmission unit and transmitted to the drive wheels. Furthermore, by releasing the first clutch and engaging the second clutch, the power from the engine is shifted by the automatic transmission unit and transmitted to the drive wheels while the motor generator is disconnected from the input shaft of the automatic transmission unit. can do.

JP, 2006-011072, A

  In the above hybrid vehicle, the first and second clutches are appropriately engaged or released so that the other of the engine and the motor is not driven by the drive wheels when traveling from one of the engine and the motor by power. Efficiency (fuel consumption) can be improved. On the other hand, when an abnormality occurs in any of the first and second clutches, it is difficult to properly connect the engine and the motor to the driving wheel and to properly disconnect the driving wheel. Therefore, in the hybrid vehicle as described above, it is important to accurately determine the abnormality of the first and second clutches. However, Patent Document 1 discloses any abnormality determination procedure for the first and second clutches. Not.

  Accordingly, the invention of the present disclosure is a hybrid vehicle including an engine coupled to a drive wheel via a first clutch, and an electric motor coupled to the drive wheel via a second clutch in parallel with the engine. The main object is to accurately determine the abnormality of the second clutch.

  A control device for a hybrid vehicle according to the present disclosure includes an engine coupled to drive wheels via a first clutch, and an electric motor coupled to the drive wheels via a second clutch in parallel with the engine. Output of torque of the electric motor or the engine when a release command or engagement command is given to the first clutch and an engagement command or release command is given to the second clutch And an abnormality determining means for determining an abnormality of the first and second clutches based on a change in the vehicle state according to the condition.

  In the hybrid vehicle controlled by this control device, when an abnormality has occurred in either the first or second clutch, the torque from the electric motor or engine is applied to the engagement command and the release command for the first and second clutches. May not be transmitted to an element determined according to the combination of the above, or may be transmitted to an element that is not originally assumed. Therefore, when an abnormality has occurred in either the first or second clutch, the vehicle state such as the engine speed or vehicle speed when the torque is output from the motor or engine, such as the difference in engine speed between the engine and the motor. Changes from the original value determined according to the combination of the engagement command and the release command for the first and second clutches. In view of this, the abnormality determination means of the control device is configured so that the motor or engine in a state where the release command or the engagement command is given to the first clutch and the engagement command or the release command is given to the second clutch. Abnormalities in the first and second clutches are determined based on changes in the vehicle state in accordance with the torque output. As a result, it is possible to accurately determine abnormality of the first and second clutches.

  In addition, the abnormality determination unit is configured to output the torque to the motor when the engine operation is stopped, the release command is given to the first clutch, and the engagement command is given to the second clutch. When the number of revolutions or the amount of change in the number of revolutions changes, it may be determined that the first clutch is locked (ON stuck), and the engine speed or the amount of change in the number of revolutions may be determined. If there is no change, it may be determined that the first clutch is not locked in the engaged state. Such determination processing may be executed when the hybrid vehicle system is started or just before the system is stopped.

  Further, the abnormality determining means is configured to output the engine speed or the amount of change in the engine speed when the motor is output in a state where the engine operation is stopped and the engagement command is given to the first and second clutches. If there is no change, it may be determined that the first or second clutch is stuck in the released state (OFF sticking). Such determination processing may also be executed when the hybrid vehicle system is started or just before the system is stopped.

  The abnormality determining means determines that the first or second clutch is stuck in the released state, stops the engine operation, gives a release command to the first clutch, and receives the second clutch. If the vehicle speed does not change when the motor outputs torque in a state where the engagement command is given, it may be determined that the second clutch is stuck in the released state. When the vehicle speed changes, it may be determined that the first clutch is stuck in the released state. Such determination processing may be executed when the hybrid vehicle starts (at the start of traveling).

  Further, the abnormality determination means includes an engine and an electric motor when a release command is given to the second clutch in a state where the first clutch is engaged according to the engagement command and the engine is outputting torque. If the rotational speed difference is less than or equal to a predetermined value, it may be determined that the second clutch is locked in the engaged state. In addition, the abnormality determination unit is configured such that when the first clutch is engaged according to the engagement command and the engine is outputting torque, the engine and the motor when the engagement command is given to the second clutch. If the rotational speed difference between the first clutch and the second clutch is greater than or equal to a predetermined value, it may be determined that the second clutch is stuck in the released state. Such determination processing may be executed while the hybrid vehicle is traveling.

It is a schematic block diagram of the hybrid vehicle controlled by the control apparatus of this indication. 6 is a flowchart illustrating an example of a clutch abnormality determination routine that is executed when the system of a hybrid vehicle is started by the control device of the present disclosure. 5 is a flowchart illustrating an example of a clutch abnormality determination routine that is executed when the hybrid vehicle starts to travel by the control device of the present disclosure. 5 is a flowchart illustrating an example of a clutch abnormality determination routine that is executed while the hybrid vehicle is traveling by the control device of the present disclosure.

  Next, embodiments for carrying out the invention of the present disclosure will be described with reference to the drawings.

  FIG. 1 is a schematic configuration diagram of a hybrid vehicle 1 controlled by the control device of the present disclosure. The hybrid vehicle 1 shown in the figure is a four-wheel drive vehicle, and includes an engine 10, a motor generator MG, a power transmission device 20, a transfer 40, a clutch C0 as a first clutch, and a clutch as a second clutch. And C2. Furthermore, hybrid vehicle 1 includes a high-voltage power storage device (hereinafter simply referred to as “power storage device”) 50, an auxiliary battery (low-voltage battery) 55, and a power control device (hereinafter referred to as “PCU”) that drives motor generator MG. 60 and a hybrid electronic control unit (hereinafter referred to as “HVECU”) 70 which is a control device of the present disclosure that controls the entire vehicle.

  The engine 10 is an internal combustion engine that outputs power from a crankshaft 11 by causing an air-fuel mixture of hydrocarbon fuel such as gasoline or light oil and air to explode in a plurality of combustion chambers. As illustrated, the engine 10 includes a starter (engine starter) 12 that cranks and starts the engine 10, an alternator 13 that is driven by the engine 10 to generate electric power, and the like. Further, the crankshaft 11 of the engine 10 is connected to a flywheel damper 14.

  The engine 10 is controlled by an engine electronic control unit (hereinafter referred to as “engine ECU”) 15 which is a microcomputer including a CPU (not shown). The engine ECU 15 executes intake air amount control, fuel injection control, ignition timing control and the like so as to obtain torque required for the engine 10 based on a command signal from the HVECU 70 and signals from various sensors. Further, the engine ECU 15 controls auxiliary equipment of the engine 10 such as the starter 12. Further, the engine ECU 15 calculates the rotational speed Ne of the engine 10 (crankshaft 11) based on an output signal of a crank angle sensor (not shown).

  Motor generator MG is a synchronous generator motor (three-phase AC motor) having a rotor in which permanent magnets are embedded and a stator around which three-phase coils are wound. Motor generator MG operates as an electric motor that is driven by electric power from power storage device 50 to generate power, and outputs regenerative braking torque when hybrid vehicle 1 is braked. Motor generator MG also functions as a generator that generates electric power using at least a part of the power from engine 10 that is operated under load. Motor generator MG exchanges power with power storage device 50 via PCU 60.

  The power transmission device 20 includes a starting device 21 having a multi-plate or single-plate lockup clutch 22, a torque converter (fluid transmission device), a damper device (not shown), a mechanical oil pump 23, a transmission mechanism (automatic transmission). Machine) 24, hydraulic control device 30 and the like. The starting device 21 has a front cover coupled (fixed) so as to rotate integrally with the transmission shaft 17 and the pump impeller of the torque converter. The lockup clutch 22 includes the front cover and an input shaft 26 of the speed change mechanism 24. Are connected to each other and the connection between them is released. The mechanical oil pump 23 is driven by the power from the engine 10 and sucks hydraulic oil (ATF) stored in an oil pan (not shown) and pumps it to the hydraulic control device 30.

  The transmission mechanism 24 is configured as, for example, a four- to ten-speed transmission, and includes a plurality of planetary gears and a plurality of clutches and brakes (friction engagement elements). The speed change mechanism 24 changes the power transmitted from the transmission shaft 17 to the input shaft 26 via the torque converter or the lock-up clutch 22 in a plurality of stages and outputs it from the output shaft 27.

  The hydraulic control device 30 includes a valve body in which a plurality of oil passages are formed, a plurality of regulator valves, a plurality of linear solenoid valves, and the like, and adjusts the hydraulic pressure from the mechanical oil pump 23 to adjust the lock-up clutch 22 and the like. This is supplied to the clutch and brake of the speed change mechanism 24. The hydraulic control device 30 is controlled by a transmission electronic control device (hereinafter referred to as “TMECU”) 25 which is a microcomputer including a CPU (not shown). As a result, the lockup clutch 22 and the clutch and brake of the speed change mechanism 24 are controlled so as to operate according to the state of the hybrid vehicle 1. The hybrid vehicle 1 has an electric oil pump 29 controlled by the TMECU 25 in addition to the mechanical oil pump 23. The electric oil pump 29 is used as an auxiliary. For example, when the hydraulic pressure is not output from the mechanical oil pump 23 when the engine 10 is stopped, the hydraulic pressure from the electric oil pump 29 is changed to the hydraulic control device 30. To be supplied.

  The transfer 40 includes a center differential and a differential lock mechanism (both not shown) that locks the center differential, and transmits power from the output shaft 27 of the transmission mechanism 24 to the front propeller shaft 41 (first shaft) and the rear propeller shaft 42. (The second axis) can be distributed and transmitted. The power output to the front propeller shaft 41 by the transfer 40 is transmitted to the front drive wheel Wf via the front differential gear 43, and the power output to the rear propeller shaft 42 by the transfer 40 passes through the rear differential gear 44. To the rear drive wheel Wr.

  The clutch C0 connects the crankshaft 11 and the transmission shaft 17 of the engine 10 to each other and releases the connection between them. In this embodiment, the clutch C0 includes a clutch hub that is always connected to the crankshaft 11 via the flywheel damper 14, a clutch drum that is always connected to the transmission shaft 17, a piston, a plurality of friction plates, and a separator plate, respectively. It is a multi-plate friction type hydraulic clutch (friction engagement element) having a hydraulic servo constituted by an engagement oil chamber to which hydraulic oil is supplied, a centrifugal hydraulic pressure cancellation chamber, and the like. However, the clutch C0 may be a single plate friction type hydraulic clutch. In the present embodiment, the clutch C0 is released as the hydraulic pressure in the engagement oil chamber decreases, and engages as the hydraulic pressure in the engagement oil chamber increases, so-called normally open type (normally open). Type) clutch. When the clutch C0 is engaged, the engine 10 (crankshaft 11) is connected to the front drive wheel Wf and the rear drive wheel Wr via the flywheel damper 14, the clutch C0, the transmission shaft 17, the power transmission device 20, the transfer 40, and the like. Connected.

  Clutch C2 connects the rotor of motor generator MG and transmission shaft 17 to each other and releases the connection between them. In the present embodiment, the clutch C2 is a hydraulic dog clutch. However, the clutch C2 may be a multi-plate friction hydraulic clutch or a single-plate friction hydraulic clutch. In the present embodiment, the clutch C2 is engaged when the hydraulic pressure is not supplied to the hydraulic servo, and is released when the hydraulic pressure is supplied to the hydraulic servo, so-called normally closed type (normally closed type). The clutch. When the clutch C2 is engaged, the motor generator MG (rotor) is connected in parallel with the engine 10 via the clutch C2, the transmission shaft 17, the power transmission device 20, the transfer 40, etc., to the front drive wheels Wf and the rear drive wheels Wr. Connected to

  In the present embodiment, clutches C0 and C2 are arranged inside the stator of motor generator MG, as shown in FIG. The hydraulic control device 30 has two linear solenoid valves that regulate the line pressure as the original pressure and supply the line pressure to the hydraulic servo of the clutch C0 or C2, and the linear solenoid valves corresponding to the clutches C0 and C2. Is controlled by the TMECU 25 in response to a command signal from the HVECU 70.

  The power storage device 50 is, for example, a lithium ion secondary battery or a nickel hydride secondary battery having a rated output voltage of about 200 to 300V. The power storage device 50 is managed by a power management electronic control device (not shown, hereinafter referred to as “power management ECU”), which is a microcomputer including a CPU (not shown). The power management ECU determines the SOC (charge rate) and allowable charge power of the power storage device 50 based on the voltage between terminals from the voltage sensor of the power storage device 50, the charge / discharge current from the current sensor, the battery temperature from the temperature sensor, and the like. The allowable discharge power is calculated. Power storage device 50 may be a capacitor or may include both a secondary battery and a capacitor. The auxiliary battery 55 is a lead storage battery having a rated output voltage of 12 V, for example, and is charged by the electric power from the alternator 13. The auxiliary battery 55 supplies power to auxiliary machines such as the starter 12 of the engine 10, the electric oil pump 29, and the hydraulic control device 30, and electronic devices such as an ECU.

  PCU 60 is connected to power storage device 50 via system main relay SMR and is also connected to auxiliary battery 55. PCU 60 includes an inverter that drives motor generator MG, a boost converter, a DC / DC converter, and the like (all not shown). The inverter includes, for example, six transistors as switching elements and six diodes connected in parallel to these transistors in the reverse direction. The boost converter includes, for example, two transistors, two diodes connected in parallel to these transistors in the opposite direction, and a reactor (both not shown). The boost converter can boost the voltage from power storage device 50 and supply the boosted voltage to the inverter, and step down the voltage from the inverter and supply the same to power storage device 50. Each of the DC / DC converters includes a switching element, a transformer, and the like (not shown), and by turning on and off the switching element, the power from the high voltage system including the power storage device 50 is stepped down to reduce the low voltage system, that is, the auxiliary battery 55, It can be supplied to various auxiliary machines.

  The PCU 60 is controlled by a motor electronic control unit (hereinafter referred to as “MG ECU”) 65 which is a microcomputer including a CPU (not shown). MGECU 65 receives a command signal from HVECU 70, a pre-boosting voltage VL and a post-boosting voltage VH of the boost converter, a detection value of a resolver that detects the rotational position of the rotor of motor generator MG, a phase current applied to motor generator MG, and the like. input. The MGECU 65 performs switching control of the inverter and the boost converter based on these input signals. Further, MGECU 65 calculates the rotational speed Nm of the rotor of motor generator MG based on a detected value of a resolver (not shown).

  The HVECU 70 is a microcomputer including a CPU, a ROM, a RAM, an input / output device and the like (not shown), and exchanges various signals with the ECUs 15, 25, 65, etc. via a network (CAN). Further, the HVECU 70, for example, a signal from a start switch, an accelerator opening Acc detected by an accelerator pedal position sensor (not shown), a vehicle speed V detected by a vehicle speed sensor (not shown), a rotational speed Ne of the engine 10 from the engine ECU 15, The rotational speed Nm of the motor generator MG is input from the MGECU 65. The HVECU 70 controls opening and closing of the system main relay SMR.

  In the hybrid vehicle 1 configured as described above, when the mechanical oil pump 23 and the electric oil pump 29 are not generating hydraulic pressure due to a system stop (during parking), the clutch C0 is released and the engine 10 The connection with the transmission shaft 17 is released, and the motor generator MG and the transmission shaft 17 are connected by the engagement of the clutch C2. Then, after the system is started, the hybrid vehicle 1 starts with power from the motor generator MG with the clutch C0 released and the clutch C2 engaged. At this time, since the connection between the engine 10 and the transmission shaft 17 is released by the clutch C0, it is possible to prevent the engine 10 from rotating and improve the efficiency (fuel consumption) in the hybrid vehicle 1.

  Further, the HVECU 70 transmits an engagement command (ON command) and a release command (OFF command) of the clutches C0 and C2 to the TMECU 25 according to the traveling state of the hybrid vehicle 1. Specifically, when a predetermined engine start condition is established after the hybrid vehicle 1 starts, the HVECU 70 transmits an engagement command for the clutch C0 to the TMECU 25. The TMECU 25 that has received the engagement command controls the hydraulic control device 30 so that the clutch C0 is engaged, and appropriately executes slip control of the clutch C0 so that the engagement shock of the clutch C0 does not occur. After engagement of the clutch C0, the HVECU 70 controls the motor generator MG so as to crank the engine 10 in cooperation with the engine ECU 15 and the MGECU 65, and starts fuel injection and ignition to start the engine 10. After the clutch C0 is thus engaged and the engine 10 is started, the motor generator MG generates power while operating the engine 10 at an operating point near the optimum fuel consumption line according to the SOC of the power storage device 50. The power storage device 50 is charged with the electric power generated, or the motor generator MG is driven by the electric power from the power storage device 50 to output torque from both the engine 10 and the motor generator MG to the front and rear drive wheels Wf, Wr. can do. Thereby, the fuel consumption of the hybrid vehicle 1 can be further improved.

  Note that after the clutch C0 is engaged, the engine 10 is cranked by the motor generator MG, so that the discharge of the auxiliary battery 55 can be suppressed. However, when the engine 10 is started, the engine 10 is It goes without saying that it may be cranked. In this case, after the engine 10 is started by cranking of the starter 12, the clutch C0 may be engaged while performing slip control.

  Further, when a predetermined release condition for the clutch C2 is established as the vehicle speed V increases, the HVECU 70 transmits a release command for the clutch C2 to the TMECU 25, and the TMECU 25 performs hydraulic control so that the clutch C2 is released. The apparatus 30 is controlled. In this way, the clutch C2 is released and the motor generator MG is disconnected from the transmission shaft 17 during high-speed cruise of the hybrid vehicle 1, thereby preventing the motor generator MG from being accompanied and improving the efficiency (fuel consumption) in the hybrid vehicle 1. be able to.

  Next, an abnormality determination procedure for the clutches C0 and C2 in the hybrid vehicle 1 will be described with reference to FIGS.

  FIG. 2 is a flowchart showing an example of a clutch abnormality determination routine executed by, for example, the HVECU 70 when the start switch is turned on by the driver and the hybrid vehicle 1 is activated. The clutch abnormality determination routine of FIG. 2 is executed by the HVECU 70 immediately after the start switch is turned on and the system main relay is closed (turned on) with the shift position set to the parking position or neutral position by the driver. . While the clutch abnormality determination routine of FIG. 2 is executed, the operation of the engine 10 is stopped.

  At the start of the routine of FIG. 2, the HVECU 70 (CPU not shown) first transmits a release command for the clutch C0 and an engagement command for the clutch C2 to the TMECU 25 (step S100). Next, a torque command of motor generator MG is set so as to output a torque that does not cause hybrid vehicle 1 to move forward, and the set torque command is transmitted to MGECU 65 (step S110). Further, the HVECU 70 inputs the rotational speed Ne of the engine 10 (crankshaft 11) from the engine ECU 15 at the timing when the torque is output from the motor generator MG when the PCU 60 is controlled by the MGECU 65 (step S120), and the rotational speed Ne is a value. It is determined whether it is 0 (step S130).

  Here, if the clutch C0 is engaged, that is, locked in the engaged state (ON-fixed) in spite of the release command in step S100, the motor generator MG transmits to the transmission shaft 17 via the clutch C2. The transmitted torque is transmitted to the crankshaft 11, and the rotational speed Ne becomes higher than 0. For this reason, when it is determined in step S130 that the rotational speed Ne is not 0 (step S130: NO), the HVECU 70 considers that the clutch C0 is fixed in the engaged state and is provided on an instrument panel (not shown). A command signal is transmitted to a meter control device (not shown) so as to turn on the predetermined warning light (step S135). Further, when the clutch C0 is fixed in the engaged state as described above, the power from the engine 10 can be transmitted to the front and rear drive wheels Wf and Wr via the transmission shaft 17 and the like. Therefore, after the process of step S135, the HVECU 70 turns on the engine retreat travel flag so as to execute the engine retreat travel in which the hybrid vehicle 1 travels with power from only the engine 10 with the clutch C2 released (step S135). S137) This routine is ended. After completion of this routine, when another READY-ON permission condition is satisfied, a READY lamp installed on an instrument panel (not shown) is turned on, and the engine evacuation traveling of the hybrid vehicle 1 is permitted.

  On the other hand, if clutch C0 is released in accordance with the release command issued in step S100 and clutch C2 is engaged in accordance with the engagement command generated in step S100, motor generator MG The torque transmitted to the transmission shaft 17 via the clutch C2 is not transmitted to the crankshaft 11, and the rotational speed Ne of the engine 10 is originally 0. However, when the clutch C2 is fixed in the released state (OFF fixed), even if the clutch C0 is fixed in the engaged state, the torque from the motor generator MG is not transmitted to the crankshaft 11 and rotates. The number Ne has the value 0.

  For this reason, if it is determined in step S130 that the rotational speed Ne is 0, the HVECU 70 further determines whether or not the clutches C0 and C2 are abnormal without giving a release command to the clutch C2. A C0 engagement command is transmitted to TMECU 25 (step S140). Next, the HVECU 70 sets the torque command of the motor generator MG so as to output a torque that does not advance the hybrid vehicle 1 when the time required for the engagement of the clutch C0 has elapsed, and sends the set torque command to the MGECU 65. Transmit (step S150). Further, the HVECU 70 inputs the rotational speed Ne of the engine 10 from the engine ECU 15 at the timing when the torque is output from the motor generator MG when the PCU 60 is controlled by the MGECU 65 (step S160), and is the rotational speed Ne higher than 0? It is determined whether or not (step S170).

  If the clutch C0 is engaged in response to the engagement command and torque is output from the motor generator MG to the transmission shaft 17, the torque of the motor generator MG is transmitted to the crankshaft 11, and the rotational speed Ne is 0 or less. Also gets higher. When the rotational speed Ne becomes higher than 0, the clutch C0 is engaged according to the engagement command and the clutch C2 is engaged (however, the clutch C2 is engaged). The possibility of being stuck in the state remains.) That is, in this case, the hybrid vehicle 1 can be started by the power from the motor generator MG with the clutch C0 disengaged and the clutch C2 engaged. Therefore, when it is determined in step S170 that the rotational speed Ne is higher than the value 0, the HVECU 70 turns off the clutch abnormality flag that is turned on when the clutches C2 and C0 are abnormal (step S180). Further, HVECU 70 transmits a release command for clutch C0 to TMECU 25 in order to start hybrid vehicle 1 with the power from motor generator MG (step S190), and ends this routine.

  On the other hand, if it is determined in step S170 that the rotational speed Ne is not higher than 0, that is, if it is determined that the rotational speed Ne is 0, the torque from the motor generator MG is determined. Is not transmitted to the crankshaft of the engine 10. That is, in this case, the clutch C0 or the clutch C2 is stuck in the released state. For this reason, when it is determined in step S170 that the rotational speed Ne is not higher than the value 0, the HVECU 70 transmits a command signal to a meter control device (not shown) so as to turn on the warning lamp, and the clutch The abnormality flag is turned on (step S185). Further, the HVECU 70 transmits a release command for the clutch C0 to the TMECU 25 (step S190), and ends this routine. The above-described clutch abnormality determination routine of FIG. 2 is executed after the system startup of the hybrid vehicle 1, so that before the hybrid vehicle 1 starts running, the clutch C0 is locked in engagement and the clutch C0 or C2 is released. It is possible to determine the occurrence of sticking in the state.

  FIG. 3 is a flowchart showing an example of a clutch abnormality determination routine executed when the hybrid vehicle 1 starts. The clutch abnormality determination routine of FIG. 3 is executed by the HVECU 70 when the driver sets the shift position to the drive position or the reverse position after the clutch abnormality flag is turned on in step S185 of FIG. While the clutch abnormality determination routine of FIG. 3 is executed, the operation of the engine 10 is stopped.

  At the start of the routine of FIG. 3, the HVECU 70 inputs the accelerator opening Acc from the accelerator pedal position sensor (step S200), and the accelerator opening Acc exceeds 0%, that is, the accelerator pedal is depressed by the driver. It is determined whether or not (step S210). When the processes of steps S200 and S210 are repeatedly executed and it is determined that the accelerator opening degree Acc exceeds 0%, the HVECU 70 inputs the vehicle speed V from the vehicle speed sensor (step S220), and the vehicle speed V has a value of 0. It is determined whether or not it exceeds (step S230).

  As described above, the hybrid vehicle 1 of the present embodiment starts with the power from the motor generator MG with the clutch C0 released and the clutch C2 engaged. In addition, the clutch abnormality flag is turned on in step S185 in FIG. 2 when one of the clutches C0 and C2 is stuck in the released state. Therefore, if it is determined in step S230 that the vehicle speed V exceeds the value 0, the torque from the motor generator MG is transmitted to the transmission shaft because the clutch C2 is normally engaged according to the engagement command. 17 and the power transmission device 20 are transmitted to the front and rear drive wheels Wf and Wr, while the clutch C0 is fixed in the released state. Therefore, when it is determined in step S230 that the vehicle speed V exceeds the value 0, the HVECU 70 engages the clutch C2 while prohibiting the operation of the engine 10 and uses the power from only the motor generator MG to drive the hybrid vehicle. In order to execute the motor retreat travel for traveling 1, the motor retreat travel flag is turned on (step S 240), and this routine is terminated.

  In contrast, if it is determined in step S230 that the vehicle speed V does not exceed the value 0, that is, if it is determined that the vehicle speed V is the value 0, the clutch C0 is normally released. Since the clutch C2 is fixed in the released state, the torque from the motor generator MG is not transmitted to the transmission shaft 17. For this reason, if it is determined in step S230 that the vehicle speed V does not exceed the value 0, the HVECU 70 turns on the engine retreat travel flag to execute the engine retreat travel described above (step S250), and ends this routine. . In this case, after the end of this routine, prior to the execution of the engine retracting travel, the clutch C0 is engaged and the cranking by the starter 12 is executed to start the engine 10. 3 is executed when the hybrid vehicle 1 starts, it is determined which of the clutches C0 and C2 is stuck in the released state, and the clutch C0 or C2 is determined. It is possible to execute an appropriate evacuation traveling according to the abnormality.

  FIG. 4 is a flowchart illustrating an example of a clutch abnormality determination routine that is executed while the hybrid vehicle 1 is traveling. In the clutch abnormality determination routine of FIG. 4, the clutch C0 is engaged after the hybrid vehicle 1 starts running, and the engine 10 is started, and torque from the engine 10 is transmitted to the front and rear drive wheels via the transmission shaft 17 and the like. It is executed by the HVECU 70 every predetermined time while being output to Wf and Wr.

  At the start of the routine of FIG. 4, the HVECU 70 inputs information such as the vehicle speed V indicating the traveling state of the hybrid vehicle 1 and the values of various flags (step S300). Next, the HVECU 70 determines whether or not the traveling state of the hybrid vehicle 1 is a state where the clutch C2 can be released based on the information input in step S300 (step S310). In step S310, for example, when the hybrid vehicle 1 is cruising at high speed, it is determined that the clutch C2 can be released. If it is determined in step S310 that the clutch C2 can be released, the HVECU 70 transmits a clutch C2 release command to the TMECU 25 (step S320), and then the rotational speed Ne of the engine 10 and the rotational speed Nm of the motor generator MG. The determination process (step S330) for the rotation speed difference ΔN is executed. In the process of step S330, a rotation speed difference ΔN (= Ne−Nm) obtained by subtracting the rotation speed Nm of the motor generator MG from the rotation speed Ne of the engine 10 is a predetermined threshold value ΔNref1 (for example, a value around 300 rpm). It is determined whether or not a state of less than a predetermined time has continued for a predetermined time (for example, several tens of mSec).

  Here, when the clutch C2 is normally released in response to the release command issued in step S320 while the torque from the engine 10 is transmitted to the transmission shaft 17, the motor generator MG and the transmission shaft 17 By releasing the connection, the rotational speed Ne of the engine 10 does not change much, whereas the rotational speed Nm of the motor generator MG decreases. On the other hand, when the clutch C2 remains engaged even though the release command is issued in a state where the torque from the engine 10 is transmitted to the transmission shaft 17, the motor generator MG and the transmission shaft 17 By maintaining the connection, the rotational speed Ne of the engine 10 and the rotational speed Nm of the motor generator MG substantially coincide with each other. For this reason, when the HVECU 70 determines that the state where the rotational speed difference ΔN is less than the threshold value ΔNref1 has continued for the predetermined time or longer (step S340: YES), the HVECU 70 considers the clutch C2 to be locked in the engaged state, and A command signal is transmitted to a meter control device (not shown) so as to turn on the warning lamp (step S350), and this routine is terminated. In this case, after the end of this routine, necessary fail-safe processing such as limiting the maximum vehicle speed is executed. If a negative determination is made in step S340, it means that the clutch C2 is not stuck in the engaged state.

  On the other hand, if it is determined in step S310 that the clutch C2 cannot be released, or if it is determined in step S340 that the state where the rotational speed difference ΔN is less than the threshold value ΔNref1 has not continued for a predetermined time or longer, the HVECU 70 As in step S300, information indicating the traveling state of the hybrid vehicle 1 such as vehicle speed V and various flag values are input (step S360). Further, the HVECU 70 determines whether or not the traveling state of the hybrid vehicle 1 is a state in which the clutch C2 can be engaged based on the information input in step S360 (step S370). If it is determined in step S370 that the clutch C2 cannot be engaged, the HVECU 70 ends this routine at that time.

  If it is determined in step S370 that the clutch C2 can be engaged, the HVECU 70 transmits an engagement command for the clutch C2 to the TMECU 25 (and the MGECU 65) (step S380). When the clutch C2 is engaged while the hybrid vehicle 1 is traveling, the motor generator MG is controlled by the MGECU 65 so that the rotational speed Nm is synchronized with the rotational speed of the transmission shaft 17, that is, the rotational speed Ne of the engine 10. Further, the HVECU 70 executes a determination process (step S390) for the rotational speed difference ΔN between the rotational speed Ne of the engine 10 and the rotational speed Nm of the motor generator MG. In the process of step S390, a state where the rotational speed difference ΔN obtained by subtracting the rotational speed Nm of the motor generator MG from the rotational speed Ne of the engine 10 is equal to or larger than a predetermined threshold value ΔNref2 (for example, a value around 300 rpm) is predetermined. It is determined whether or not it has continued for a time (for example, several tens of mSec).

  When the clutch C2 is normally engaged according to the engagement command issued in step S380 in a state where torque from the engine 10 is transmitted to the transmission shaft 17, the motor generator MG and the transmission shaft 17 are connected. Thus, the rotational speed Ne of the engine 10 and the rotational speed Nm of the motor generator MG substantially coincide with each other. On the other hand, when the clutch C2 remains released despite the engagement command being made in a state where the torque from the engine 10 is transmitted to the transmission shaft 17, the rotational speed Nm of the motor generator MG is The rotational speed Ne does not coincide with the rotational speed Ne of the engine 10, and the rotational speed Nm is significantly lower than the rotational speed Ne.

  For this reason, when the HVECU 70 determines that the state where the rotational speed difference ΔN is equal to or greater than the threshold value ΔNref2 has continued for a predetermined time or longer (step S400: YES), the HVECU 70 considers that the clutch C2 is fixed in the released state, and A command signal is transmitted to a meter control device (not shown) so as to light up (step S410), and this routine is terminated. In this case, after the completion of this routine, necessary fail-safe processing is executed, and the engine retreat travel flag is turned on to execute the engine retreat travel described above. If a negative determination is made in step S400, the clutch C2 is not stuck in the released state. By executing the clutch abnormality determination routine of FIG. 4 as described above, it is possible to determine whether the clutch C2 is locked in the engaged state or in the released state when the hybrid vehicle 1 is traveling. It becomes.

  As described above, the HVECU 70 as the control device of the present disclosure includes the engine 10 connected to the front and rear drive wheels Wf and Wr via the clutch C0, and the engine 10 in front via the clutch C2 in parallel. The hybrid vehicle 1 including the motor generator MG coupled to the rear drive wheels Wf and Wr is controlled. Then, the HVECU 70 is in a vehicle state according to the torque output of the motor generator MG or the engine 10 in a state where the release command or engagement command is given to the clutch C0 and the engagement command or release command is given to the clutch C2. It functions as an abnormality determination means (steps S100 to S190, S200 to S250, S300 to S410) for determining the abnormality of the clutches C0 and C2 based on the change of.

  That is, in the hybrid vehicle 1, when an abnormality occurs in any of the clutches C0 and C2, the torque from the motor generator MG and the engine 10 depends on the combination of the engagement command and the release command for the clutches C0 and C2. It will not be transmitted to a fixed element, or it may be transmitted to an element that is not originally assumed. Accordingly, when an abnormality has occurred in any of the clutches C0 and C2, for example, when the torque is output from the motor generator MG or the engine 10, the rotational speed Ne, the vehicle speed V, the rotational speed between the engine 10 and the motor generator MG, for example. The vehicle state such as the difference ΔN changes from the original state determined according to the combination of the engagement command and the release command for the clutches C0 and C2. Based on this, in the hybrid vehicle 1, the HVECU 70 executes the processes of steps S100 to S190, S200 to S250, and S300 to S410 as described above. As a result, it is possible to accurately determine the abnormality of the clutches C0 and C2, and to perform appropriate retreat travel and fail-safe processing according to the abnormality occurring in the clutches C0 and C2.

  In steps S130 and S170 in FIG. 2, instead of comparing the rotational speed Ne of the engine 10 with a threshold value, the amount of change in the rotational speed Ne may be compared with a threshold value. Even if the routine of FIG. 3 is executed, it cannot be determined whether the clutches C0 and C2 are abnormal unless the accelerator pedal is depressed by the driver. Accordingly, the routine of FIG. 3 advances the hybrid vehicle 1 slightly forward or backward (vehicle speed V is 2 to 2) when the driver does not depress the accelerator pedal until a predetermined time elapses after selection of the drive position, for example. It may be modified such that the process after step S220 is executed after the torque (running at about 3 km / h) is output to the motor generator MG. 2 and FIG. 3 may be executed after the hybrid vehicle 1 is parked, before the start switch is turned off by the driver, or after the start switch is turned off. In this case, the engine evacuation travel flag and the motor evacuation travel flag set in steps S137, S240, and S250 are preferably made valid until the next start of the hybrid vehicle 1. The hybrid vehicle 1 includes a plurality of ECUs 15, 25, 65, 70, etc. All or a part of these ECUs may be integrated into a single ECU. Furthermore, it goes without saying that the hybrid vehicle 1 may be configured as a front wheel drive vehicle or a rear wheel drive vehicle.

  And the invention of this indication is not limited to the above-mentioned embodiment at all, and it cannot be overemphasized that various changes can be made within the range of the extension of this indication. Furthermore, the above-described embodiment is merely a specific form of the invention described in the Summary of Invention column, and does not limit the elements of the invention described in the Summary of Invention column.

  The invention of the present disclosure can be used in the hybrid vehicle manufacturing industry and the like.

  DESCRIPTION OF SYMBOLS 1 Hybrid vehicle, 10 Engine, 11 Crankshaft, 12 Starter, 13 Alternator, 14 Flywheel damper, 15 Engine electronic control unit (engine ECU), 17 Transmission shaft, 20 Power transmission device, 21 Starting device, 22 Lock-up clutch, 23 mechanical oil pump, 24 transmission mechanism, 25 transmission electronic control unit (TMECU), 26 input shaft, 27 output shaft, 29 electric oil pump, 30 hydraulic control device, 40 transfer, 41 front propeller shaft, 42 rear propeller shaft , 43 front differential gear, 44 rear differential gear, 50 power storage device, 55 auxiliary battery, 60 power control unit (PCU), 65 motor electronic control unit (MGECU), 70 hybrid electronic control unit (HV) CU), C0, C2 clutch, MG motor generator, SMR system main relay, Wf front drive wheels, Wr rear drive wheel.

Claims (1)

A control device for a hybrid vehicle, comprising: an engine coupled to drive wheels via a first clutch; and an electric motor coupled to the drive wheels via a second clutch in parallel with the engine,
Changes in the vehicle state according to the torque output of the electric motor or the engine when a release command or engagement command is given to the first clutch and an engagement command or release command is given to the second clutch A control apparatus for a hybrid vehicle, comprising abnormality determining means for determining abnormality of the first and second clutches based on the above.

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