JP4405983B2 - Control device for hybrid vehicle - Google Patents

Description

  The present invention relates to a control device for a hybrid vehicle.

As a hybrid vehicle, an internal combustion engine, a first electric motor connected to an output shaft of the internal combustion engine to start the internal combustion engine and generating electric power when driven by the internal combustion engine, and a second traveling vehicle connected to the drive wheel There is known an apparatus including the electric motor, and a technique described in Patent Document 1 can be given as an example.
Japanese Patent Application Laid-Open No. 8-232817

  In the above-described technology, a clutch is inserted between the driving motor and the driving wheel, and the clutch is disconnected during high-speed driving to prevent the driving motor from being driven from the driving wheel, and when the vehicle speed decreases, the clutch is restarted. It is also conceivable to configure so as to be coupled.

  In the above-described configuration, if the clutch is not engaged at the time of starting of the vehicle for any reason, when the vehicle is started by the electric motor for driving, the vehicle cannot immediately travel and the driving feeling is lowered. In that case, it is possible to select the internal combustion engine as a power source to avoid a decrease in travel feeling, but traveling by the internal combustion engine increases fuel consumption compared to that of the electric motor.

  Accordingly, an object of the present invention is to eliminate the above-described problems, and in a hybrid vehicle in which a clutch is interposed between a traveling motor and a drive wheel, the clutch is coupled when the vehicle starts for some reason. An object of the present invention is to provide a control device for a hybrid vehicle that prevents an increase in fuel consumption while avoiding a decrease in driving feeling when there is no vehicle.

In order to achieve the above object, according to a first aspect of the present invention, there is provided an internal combustion engine and a transmission connected to an output shaft of the internal combustion engine for inputting an output of the internal combustion engine and shifting the transmission to drive wheels. A first electric motor that is connected to the output shaft of the internal combustion engine and that starts the internal combustion engine when energized, and that generates electric power when driven by the internal combustion engine; and a traveling motor connected to the drive wheel A second electric motor, a clutch that is interposed between the second electric motor and the driving wheel and transmits power between the second electric motor and the driving wheel when coupled, and the first and second In a control device that controls the operation of a hybrid vehicle including a battery that charges and discharges electric power with an electric motor, clutch engagement determining means that determines whether or not the clutch is engaged when the vehicle starts, and The clutch is engaged When it is determined that not, the while stopping fuel supply to an internal combustion engine, by starting the first electric motor motoring the internal combustion engine, said transmission connected to an output shaft of the internal combustion engine was composed as and a start control execution means for executing a start control for starting the vehicle in Rukoto rotates the drive wheel via.

  In the hybrid vehicle control device according to claim 2, the hybrid vehicle control device includes a hydraulic pump connected to the output shaft of the internal combustion engine and driven by the output of the internal combustion engine to generate hydraulic pressure, and the start control execution means includes The clutch is coupled with the generated hydraulic pressure.

  In the hybrid vehicle control device according to claim 3, the start control execution means is configured to start the second electric motor and then use the second electric motor after coupling the clutch with the generated hydraulic pressure. It was configured to switch to running.

In the hybrid vehicle control device according to claim 1, when starting the vehicle, it is determined whether the clutch is engaged, and when it is determined that the clutch is not engaged, the fuel supply to the internal combustion engine is performed. remains stopped, start the first electric motor with an internal combustion engine motoring, since it is configured as to start the vehicle in Rukoto rotate the drive wheel via a transmission connected to the output shaft of the internal combustion engine, The internal combustion engine is motored through the activation of the first electric motor to start the vehicle immediately, thereby avoiding a decrease in running feeling, and while the fuel supply is stopped, the first electric motor is activated to start the internal combustion engine. As a result of the motoring , an increase in fuel consumption can also be prevented.

  Further, although the emission amount of emission increases when the internal combustion engine is started, it can also be avoided by not starting the internal combustion engine. In addition, even when an electric motor travel button or the like is installed in the driver's seat of the vehicle and the driver operates it, the driver's expectations can be met.

  The hybrid vehicle control device according to claim 2 includes a hydraulic pump connected to the output shaft of the internal combustion engine, driven by the output of the internal combustion engine to generate hydraulic pressure, and coupled to the clutch by the generated hydraulic pressure. Since it is configured as described above, the clutch can be quickly coupled after the start, and it is also possible to promptly switch to traveling by the originally planned second electric motor.

  In the hybrid vehicle control device according to claim 3, since the clutch is engaged with the generated hydraulic pressure, the second electric motor is started and switched to traveling by the second electric motor. It is possible to promptly switch to traveling by the originally scheduled second electric motor.

  The best mode for carrying out a hybrid vehicle control apparatus according to the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a schematic diagram generally showing a control apparatus for a hybrid vehicle according to an embodiment of the present invention.

  Reference numeral 10 in FIG. 1 indicates a hybrid vehicle (hereinafter referred to as “vehicle”). The vehicle 10 includes a transmission (shown as “T / M”) 16 between an internal combustion engine (hereinafter referred to as “engine” and shown as “ENG”) 12 and drive wheels (wheels) 14. The engine 12 is a gasoline injection spark ignition type four-cylinder engine. The transmission 16 is connected to the drive wheels 14 to change the output of the engine 12, and is transmitted to the drive wheels 14 through a differential gear (shown as “Diff”) 20 to cause the vehicle 10 to travel.

  A first electric motor (hereinafter referred to as a “first motor” and indicated as “MOT1”) 22 is directly connected to an output shaft (crankshaft; not shown) of the engine 12. The first motor 22 is a DC brushless motor, more specifically, an AC synchronous motor. The first motor 22 always rotates when the engine 12 rotates, and is energized when the engine 12 starts to crank and start the engine 12 and accelerate. It is also energized at times to assist (increase) the rotation of the engine 12.

  A second electric motor (hereinafter referred to as “second motor”, hereinafter referred to as “MOT2”) 26 for traveling is connected to the drive wheel 14 via a differential gear 20 and a clutch (hydraulic clutch) 24. The second motor 26 is also a DC brushless motor, more specifically, an AC synchronous motor. When the vehicle 10 starts, the second motor 26 is energized to drive the drive wheels 14 and, like the first motor 22, is energized during acceleration. Assisted (accelerated) driving.

  The first motor 22 generates electric power by converting kinetic energy generated by rotation of the crankshaft into electric energy when driven by the engine 12, and is generated by rotation of the drive wheels 14 when driven from the drive wheels 14. It functions as a generator (generator) that converts the revolving energy into electrical energy and regenerates it. The second motor 26 also has a regenerative function that, when coupled (coupled) by the clutch 24, converts the kinetic energy generated by the rotation of the drive wheels 14 into electric energy and outputs it when not energized.

  The first and second motors 22 and 26 are connected to a battery (shown as “BATT”) 32 via a power drive unit (shown as “PDU”) 30. The PDU 30 includes an inverter, converts direct current supplied (discharged) from the battery 32 into alternating current, supplies the alternating current to the first and second motors 22 and 26, and generates or regenerates power by the first and second motors 22 and 26. AC is converted to DC and supplied to the battery 32 (charging the battery 32). The battery 32 is formed by connecting an appropriate number of nickel-metal hydride (Ni-MH) batteries in series.

  As shown in the figure, the vehicle 10 calculates the state of charge (SOC) of an engine control unit (electronic control unit; hereinafter referred to as “ENG ECU”) 34 that controls the operation of the engine 12 and charge / discharge. A management control unit (hereinafter referred to as “MG / BATT ECU”) 36 that controls the operation of the PDU 30 and the first and second motors 22 and 26, and a shift control unit that controls the operation of the transmission 16. (Hereinafter referred to as “T / M ECU”) 40. ECUs (electronic control units) such as the above-described ENG ECU 34 are all composed of a microcomputer and are connected to each other via a signal line 42 so as to be communicable with each other.

  The clutch 24 comprises a hydraulically operated mechanical clutch, more specifically a dog clutch, and the hydraulic pressure is supplied from a hydraulic pump (shown as “OP” in the figure) 44 through a hydraulic control valve (shown as “VLV” in the figure) 46. When supplied and coupled, the power transmission between the second motor 26 and the drive wheel 14 is connected. The hydraulic pump 44 is a gear pump, is connected to the output shaft of the engine 12, and when driven by the engine 12, draws hydraulic oil from the reservoir and generates hydraulic pressure.

  FIG. 2 is a skeleton diagram of the transmission 16 shown in FIG.

  The transmission 16 includes a main shaft MS connected to the output shaft of the engine 12 (and the first motor 22) via a clutch C, a counter shaft CS arranged in parallel therewith, and a reverse counter shaft RCS. The transmission 16 is called an AMT (automatic manual transmission) or the like, and includes a transmission in which the clutch C and the first to fourth synchromesh mechanisms 16a, 16b, 16c, and 16d are operated by an actuator (not shown). . The fourth synchromesh mechanism 16d corresponds to the clutch 24 of FIG.

  The second motor 26 is connected to the motor output shaft MOS. The motor output shaft MOS is connected to the countershaft CS via the differential gear 20. A first reduction gear 16e is rotatably supported on the motor output shaft MOS, and a second reduction gear meshing with the first reduction gear 16e is coupled to an intermediate reduction shaft 16f disposed in parallel with the motor output shaft MOS. 16g, the third reduction gear 16h, and the like are fixed.

  In the differential gear 20, the final driven gear 16i meshes with the final drive gear 16j of the countershaft CS and meshes with the third reduction gear 16h of the intermediate reduction shaft 16f. The differential gear 20 is connected to the drive wheel 14 via the axle 16k.

  The first reduction gear 16e is coupled (fixed) to the motor output shaft MOS via the fourth synchromesh mechanism 16d. Of the four synchromesh mechanisms, as described with reference to FIG. 1, the fourth synchromesh mechanism 16d is supplied with hydraulic oil from a hydraulic pump 44 (not shown in FIG. 2), and outputs the first reduction gear 16e to the motor. It is driven to a coupling position for coupling to the shaft MOS, or to a separation position for separating the first reduction gear 16e from the motor output shaft MOS. Since the fourth synchromesh mechanism 16d is a dog clutch, after being driven to the coupling position where the first reduction gear 16e is coupled to the motor output shaft MOS or the separation position where it is separated from the motor output shaft MOS, the position is maintained. Does not require hydraulic pressure.

  In the transmission 16 shown in FIG. 2, when the engine 12 performs forward travel, the fourth synchromesh mechanism 16d separates the first reduction gear 16e from the motor output shaft MOS and reversely transmits the driving force to the second motor 26. While preventing, the reverse idle gear 16m on the reverse countershaft RCS is moved to the left in FIG. 2 and separated from the main reverse gear 16n and the counter reverse gear 16o.

  In this state, for example, when the counter first speed gear 16p is coupled to the counter shaft CS by the first synchromesh mechanism 16a, the first speed gear stage is established, and the rotation of the main shaft MS connected to the engine 12 by the clutch C is It is transmitted to the drive wheel 14 through the main first speed gear 16q, the counter first speed gear 16p, the counter shaft CS, the final drive gear 16j, the final driven gear 16i, the differential gear 20, and the axle 16k. Similarly, by connecting appropriate gears on the shaft via the first to third synchromesh mechanisms 16a, 16b, and 16c, it is possible to establish the second to sixth gears.

  At this time, the rotation of the final driven gear 16i connected to the drive wheel 14 is transmitted to the first reduction gear 16e via the third reduction gear 16h, the intermediate reduction shaft 16f, and the second reduction gear 16g. Since 16e is separated from the motor output shaft MOS, there is no inconvenience that the second motor 26 is rotated from the drive wheels 14 during high speed traveling.

  However, if there is no fear that the second motor 26 will over-rotate during deceleration of the vehicle 10, the first reduction gear 16e is coupled to the motor output shaft MOS via the fourth synchromesh mechanism 16d, and the second motor 26 is It is assumed that regenerative braking is performed by operating as a generator. Therefore, when the vehicle 10 stops, the first reduction gear 16e is typically coupled to the motor output shaft MOS by the fourth synchromesh mechanism 16d.

  When the second motor 26 is driven in a state where the first reduction gear 16e is coupled to the motor output shaft MOS by the fourth synchromesh mechanism 16d during the forward traveling by the engine 12, the driving force of the second motor 26 is increased. The first reduction gear 16e, the second reduction gear 16g, the intermediate reduction shaft 16f and the third reduction gear 16h, the final driven gear 16i, the differential gear 20, and the axle 16k are transmitted to the drive wheels 14 to drive the driving force of the engine 12 to the second. The driving force of the motor 26 can assist. Although the description is omitted, the same applies when the engine 12 is traveling backward.

  On the other hand, when the vehicle 10 is driven forward or backward using only the driving force of the second motor 26 without using the driving force of the engine 12, such as when the vehicle 10 is starting, the first reduction gear 16e is driven by the fourth synchromesh mechanism 16d. Is coupled to the motor output shaft MOS, and the second motor 26 is driven forward or reversely, the driving force of the second motor 26 is the same as in the case of driving while the engine 12 is traveling forward. 14 is transmitted.

  Next, the operation of the control device for the hybrid vehicle according to this embodiment will be described.

  FIG. 3 is a flowchart showing the operation. The illustrated program is executed by the MG / BATT ECU 36 when the vehicle 10 starts.

  In the following, it is determined whether or not the clutch 24 is engaged in S10. This is based on the output of a sensor (not shown in FIG. 2) for detecting the position of the first reduction gear 16e to determine whether the first reduction gear 16e is coupled to the motor output shaft MOS by the fourth synchromesh mechanism 16d. To do. When the result in S10 is affirmative, the program proceeds to S12, in which it is determined whether EV is possible, that is, whether the capacity of the battery 32, the temperature environment, or the like is checked, and whether the motor can be driven by the second motor 26 or the like.

  When the result in S12 is affirmative, the program proceeds to S14, in which the vehicle travels (starts) by the EV travel mode, that is, the second motor 26. If the result in S12 is negative, the motor 32 cannot run due to insufficient capacity of the battery 32, and therefore, the process proceeds to S16 and the engine 12 is driven by the ENG driving mode.

  Before continuing the description of FIG. 3, a typical example of the traveling of the vehicle 10 originally planned by the apparatus according to the embodiment will be described with reference to the time chart of FIG.

  First, if EV is possible, the vehicle starts with the second motor 26 (time t0). Next, when the acceleration requested by the driver is large, the engine 12 is started by the first motor 22 and switched from the second motor 26 to traveling by the engine 12 (time t1). When the engine 12 rotates independently, the first motor 22 is driven by the engine 12 to generate electricity.

  Next, when shifting to the cruise state (time t2), the engine 12 is stopped and the driving is switched to the second motor 26 again. Thereafter, when further acceleration is required (time t3), the vehicle is again switched to traveling by the engine 12, and if necessary, the second motor 26 is also driven to assist (time t4).

  Next, at the time of high-speed cruise (time t5), if the clutch 24 remains engaged, the second motor 26 is rotated from the drive wheel 14, and thus the clutch 24 is disconnected. Next, when the vehicle speed decreases (time t6), the clutch 24 is engaged again, and the second motor 26 is driven by the drive wheels 14 to generate power (regeneration). Accordingly, when the vehicle 10 is stopped, the clutch 24 remains engaged.

  However, as indicated by an imaginary line a at the right end of FIG. 4, the clutch 24 may not be engaged and the vehicle 10 may suddenly stop when a panic brake or the like is performed. In that case, when the vehicle is started next time, if it tries to run with the second motor 26, it cannot run immediately, so the running feeling is lowered. On the other hand, it is possible to select the engine 12 as a power source to avoid a decrease in travel feeling, but traveling by the engine 12 increases fuel consumption compared to that of the second motor 26.

  This embodiment aims to solve this problem. In this embodiment, the traveling of the vehicle 10 between time t0 and t1 in the time chart of FIG. 4 is described as an example.

  Returning to the description of the flow chart of FIG. 3, when it is determined negative in S10 and the clutch 24 is not engaged, that is, it is determined that the clutch 24 is disconnected, the process proceeds to S18, and similarly it is determined whether EV is possible, When the result is affirmative, the routine proceeds to S20, where it is determined that the clutch 24 is engaged while traveling by the EV traveling / clutch engagement mode, that is, by the first motor 22.

  FIG. 5 is a sub-routine flowchart showing the processing.

  In the following, in S100, the vehicle starts (runs) using the first motor 22 as a power source. Specifically, the first motor 22 is started, the engine 12 is driven by the first motor 22, and the drive wheels 14 are rotated via the transmission 16 and the differential 20 connected to the output shaft of the engine 12. At this time, the fuel supply to the engine 12 remains stopped. That is, while the engine 12 is motored by the first motor 22, the drive wheels 14 are rotated to start (run).

  Next, in S102, the clutch 24 is engaged. That is, the output shaft of the engine 12 is forcibly rotated by the first motor 22 and the hydraulic pump 44 starts to operate. Therefore, the hydraulic pressure generated by the hydraulic pump 44 is applied to the clutch 24 (fourth synchromesh mechanism). 16d) to execute the process of combining.

  Next, in S104, it is determined whether or not the clutch 24 is engaged by the same method as described in S10. When the result in S104 is negative, the process returns to S102, and when the result is affirmative, the process proceeds to S106, the power source is switched from the first motor 22 to the second motor 26, and the vehicle travels, that is, transitions to the EV travel mode.

  Returning to the description of the flow chart of FIG. 3, when the result in S18 is NO, the program proceeds to S22, and the ENG travel / clutch engagement mode is set. That is, the clutch 24 is engaged while traveling by the engine 12.

  FIG. 6 is a subroutine flowchart showing the processing.

  In the following, in S200, while supplying fuel to the engine 12, the first motor 22 is started to start the engine 12, and the drive wheel is connected via the transmission 16 and the differential 20 connected to the output shaft of the engine 12. 14 is rotated. That is, the engine 12 is started by the first motor 22, and the driving wheel 14 is rotated by the driving force of the engine 12 to start. The fuel is supplied to the engine 12 by sending a command from the ENG ECU 34 via the signal line 42.

  Next, in S202, the clutch 24 is engaged. That is, since the hydraulic pump 44 starts to operate as the engine 12 is started, a process of sending and coupling the hydraulic pressure generated by the hydraulic pump 44 to the clutch 24 is executed until the clutch coupling is determined in S204. repeat. As a result, it is determined that the clutch is engaged, and at the time when it is determined that EV is possible, the traveling by the engine 12 is switched to the traveling by the second motor 26.

In the hybrid vehicle control apparatus according to this embodiment, when the vehicle 10 starts, it is determined whether or not the clutch 24 is engaged. When it is determined that the clutch is not engaged, it is determined that EV is possible. As long as the fuel supply to the engine 12 is stopped, the first motor 22 is started, the engine 12 is motored, and the drive wheels 14 are rotated via the transmission 16 connected to the output shaft of the engine 12. Since the vehicle 10 is started, the engine 12 is motored through the activation of the first motor 22 and the vehicle 10 is started immediately to avoid a decrease in driving feeling and to supply fuel. remains stopped, by motoring the engine 12 to start the first motor 22, it is possible to prevent an increase in fuel consumption.

  Further, although the emission amount of emission increases when the engine 12 is started, it can be avoided by not starting the engine 12 as long as it is determined that EV is possible. Even when a motor travel button or the like is installed in the driver's seat of the vehicle 10 and the driver operates it, the driver's expectation can be met.

  Further, since the hydraulic pump 44 is connected to the output shaft of the engine 12 and driven by the output of the engine 12 to generate hydraulic pressure, and the clutch 24 is coupled with the generated hydraulic pressure, the clutch 24 is started after starting. Can be quickly combined, and it is also possible to quickly switch to the originally planned traveling by the second motor 26.

  In addition, after the clutch 24 is coupled with the generated hydraulic pressure, the second motor 26 is started and switched to traveling by the second motor 26. Therefore, after the start, the originally planned traveling by the second motor 26 is performed. You can switch quickly.

In this embodiment, as described above, the engine (internal combustion engine) 12, the transmission 16 connected to the output shaft of the engine 12, the output of the engine 12 being input, the speed being changed and transmitted to the drive wheels 14, Connected to the output shaft of the engine 12, the engine 12 is started when energized, and is connected to a first motor (first electric motor) 22 that generates power when driven by the engine 12, and to the driving wheel 14. A second motor (second electric motor) 26 for traveling, and a clutch 24 that is inserted between the second motor and the drive wheels and that is powered between the second motor and the drive wheels when coupled. In the control device that controls the operation of the hybrid vehicle 10 including the battery 32 that charges and discharges electric power between the first and second motors 22 and 26, the clutch 24 is operated when the vehicle 10 starts. When it is determined that the clutch engagement determining means (MG / BATT ECU 36, S10) for determining whether the clutch is engaged and the clutch 24 is not engaged, the fuel supply to the engine is stopped and the first 1 start motor 22 to motoring the engine 12, the starting control to start the vehicle 10 in Rukoto rotates the drive wheels 14 via the transmission 16 connected to an output shaft of the engine 12 Start control execution means (MG / BATT ECU 36, S18, S20, S100 to S106).

  In addition, a hydraulic pump 44 is connected to the output shaft of the engine 12 and driven by the output of the engine 12 to generate hydraulic pressure, and the start control execution means connects the clutch 24 with the generated hydraulic pressure. (MG / BATT ECU 36, S20, S102).

  Further, the start control execution means is configured to start the second motor 26 and switch to traveling by the second motor 26 after coupling the clutch 24 with the generated hydraulic pressure. MG / BATT ECUs 36, S20, S104, S106).

  In addition, in the above, the structure of the hybrid vehicle 10 is an illustration, and is not limited to it. For example, as indicated by an imaginary line in FIG. 1, an electric pump (shown as “EOP”) 50 may be provided to supply hydraulic pressure from the electric pump 50 to the clutch 24.

  Further, although a dog clutch has been described as an example of the hydraulically operated mechanical clutch 24, the invention is not limited thereto, and a clutch using spline coupling may be used.

1 is a schematic diagram showing an overall configuration of a hybrid vehicle control device according to a first embodiment of the present invention. FIG. FIG. 2 is a skeleton diagram of the transmission shown in FIG. 1. It is a flowchart which shows operation | movement of the apparatus shown in FIG. It is a time chart explaining the driving | running | working which the vehicle shown in FIG. FIG. 4 is a sub-routine flow chart showing details of an EV running / clutch engagement mode in the flow chart of FIG. 3; FIG. 4 is a sub-routine flow chart showing details of an ENG traveling / clutch engagement mode in the flow chart of FIG. 3;

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Hybrid vehicle, 12 Internal combustion engine (engine), 14 Drive wheel (wheel), 16 transmission, 22 1st electric motor (1st motor), 24 Clutch (4th synchromesh mechanism 16d), 26 2nd electric motor ( (Second motor), 34 engine control unit (ENG ECU, electronic control unit), 36 management control unit (MG / BATT ECU), 44 hydraulic pump

Claims (3)

An internal combustion engine, a transmission connected to the output shaft of the internal combustion engine, the input of the output of the internal combustion engine being input and shifting to be transmitted to the drive wheel, and the output shaft of the internal combustion engine connected to the output shaft and energized A first electric motor that starts the internal combustion engine and generates electric power when driven by the internal combustion engine, a second electric motor for traveling connected to the drive wheel, and a gap between the second electric motor and the drive wheel A hybrid vehicle comprising a clutch that transmits power between the second electric motor and drive wheels when inserted and coupled, and a battery that charges and discharges electric power between the first and second electric motors In a control device for controlling the operation of
a. Clutch engagement determining means for determining whether or not the clutch is engaged when the vehicle starts,
And b. When it is determined that the clutch is not engaged, the first electric motor is started to motor the internal combustion engine while the fuel supply to the internal combustion engine is stopped , and connected to the output shaft of the internal combustion engine a start control execution means for executing a start control for starting the vehicle in Rukoto rotates the drive wheel through the transmission that is,
A control apparatus for a hybrid vehicle, comprising:   A hydraulic pump connected to the output shaft of the internal combustion engine and driven by the output of the internal combustion engine to generate hydraulic pressure, and the start control execution means couples the clutch with the generated hydraulic pressure. The hybrid vehicle control device according to claim 1.   3. The hybrid vehicle according to claim 2, wherein the start control execution unit starts the second electric motor and switches to traveling by the second electric motor after coupling the clutch with the generated hydraulic pressure. Control device.

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