JP2013123939A - Controller of vehicle drive system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively utilize kinetic energy during deceleration of a vehicle in a system capable of transmitting engine power and motor power to an axle.SOLUTION: During deceleration of a vehicle, when the SOC of a battery 31 is lower than an upper limit threshold value, clutches 23 to 25 are all cut off, and a second MG 14 is rotary-driven by power of an axle 28 to execute MG regeneration control for charging the battery 31 with power generated by the second MG 14. When the SOC of the battery 31 is equal to or higher than the upper limit threshold value, the clutches 23 to 25 are controlled to transmit the power of the axle 28 to an engine 12, and engine regeneration control for rotary-driving the engine 12 of a fuel stop state by the power of the axle 28 is executed. During the deceleration of the vehicle, an engine revolution speed is increased to a revolution speed region enabling restarting (engine revolution speed enabling starting of engine 12 only by resuming fuel injection or ignition).

Description

  The present invention relates to a control device for a vehicle drive system including a power transmission device capable of transmitting engine power and motor generator power to a vehicle axle.

  In recent years, a hybrid vehicle equipped with an engine and an MG (motor generator) as a power source of the vehicle has attracted attention because of the social demand for low fuel consumption and low exhaust emissions. In this hybrid vehicle, for example, as described in Patent Document 1 (Japanese Patent Laid-Open No. 2003-191762), at the time of deceleration of the vehicle, the MG is driven by the power of the axle and the kinetic energy of the vehicle is powered by MG. When regenerative control is performed to convert (recover) to the battery and convert it into a kinetic energy, the kinetic energy during deceleration of the vehicle is reduced by controlling the clutch provided in the power transmission path to eliminate the energy loss due to dragging of the engine and transmission mechanism. When the EV driving is performed to drive the vehicle by driving the axle with the power of MG by the power of the battery when the remaining capacity of the battery (storage battery) is equal to or greater than a predetermined value, By controlling the clutch provided on the transmission path to eliminate the energy loss due to dragging of the engine and the speed change mechanism, the energy loss during EV traveling is reduced. There are things.

JP 2003-191762 A

  However, when the vehicle decelerates, if the remaining capacity of the battery has already reached or near its full charge capacity and the battery cannot be charged almost, the kinetic energy of the vehicle cannot be recovered into the battery, and the vehicle There is a problem that the kinetic energy at the time of deceleration cannot be used effectively.

  Accordingly, an object of the present invention is to provide a control device for a vehicle drive system that can effectively use kinetic energy during deceleration of the vehicle.

  In order to solve the above-mentioned problems, the invention according to claim 1 is directed to a power transmission device capable of transmitting engine power and power of a motor generator (hereinafter referred to as “MG”) to a vehicle axle, and MG and electric power. In a control device for a vehicle drive system including a battery to be exchanged, when the vehicle decelerates, the remaining capacity of the battery or information that changes in accordance with the remaining capacity (hereinafter collectively referred to as “remaining battery information”) is a predetermined threshold value. If the battery power level information is equal to or greater than the threshold value, the MG regeneration control is performed to drive the MG with the power of the axle and charge the battery with the electric power generated by the MG. The engine is provided with a deceleration-time regenerative control means for executing driving engine regenerative control.

  In this configuration, when the remaining battery information is lower than the threshold value when the vehicle is decelerated, it is determined that the battery can be charged, and the MG is driven by the power of the axle to generate the electric power generated by the MG. By executing the MG regenerative control that charges the vehicle, the kinetic energy of the vehicle can be converted into electric power by the MG and recovered into the battery.

  On the other hand, when the battery remaining amount information is equal to or greater than the threshold value, it is determined that the battery cannot be charged so much, and engine regeneration control is performed to drive the engine in the combustion stopped state with the power of the axle, so that the engine is decelerated. The rotational speed can be increased to a rotational speed region where the restart can be performed (an engine rotational speed region where the engine can be started simply by restarting fuel injection and ignition). This makes it possible to restart the engine quickly by simply restarting fuel injection and ignition without having to crank the engine with MG or the like when accelerating after the vehicle is decelerated. It can be effectively used as energy for restarting the engine.

  The present invention can be applied to a system including a power transmission device having various configurations capable of transmitting engine power and MG power to an axle. For example, as in claim 2, the first MG is the first MG. The power transmission device includes an MG and a second MG, and the power transmission device receives an engine input shaft that transmits engine power, a motor input shaft that transmits power of the first MG, and power of the second MG. And an output shaft that outputs power for transmission to the axle, an engine-side gear mechanism for transmitting power from the engine input shaft to the output shaft without going through the motor input shaft, and power from the motor input shaft to the engine input shaft. Between the motor-side gear mechanism and the output shaft, a motor-side gear mechanism for transmitting to the output shaft without passing through, a first clutch for intermittently transmitting power between the engine input shaft and the motor input shaft, Second to interrupt power transmission A clutch, and a third clutch for intermittently transmitting power between the engine side gear mechanism and the output shaft, and when the first clutch is connected, there is a gap between the engine side gear mechanism and the motor side gear mechanism. You may comprise so that power transmission is possible. If it does in this way, the power transmission device which transmits the power of an engine and the power of MG to the axle of a vehicle can be reduced in size.

  In this case, as in the third aspect, when performing the MG regeneration control, at least the second clutch and the third clutch are disengaged and the MG regeneration control is performed by the second MG. In this way, the engine is disconnected from the power transmission path for transmitting the axle power to the second MG, and MG regeneration control can be performed in a state where energy loss due to engine drag is eliminated. The kinetic energy can be regenerated efficiently.

  In addition, as described in claim 4, when performing engine regeneration control, the power of the axle is transmitted to the engine through the gear mechanism having the smaller gear ratio of the engine side gear mechanism and the motor side gear mechanism. It is preferable to execute first engine regenerative control for controlling each clutch and driving the engine. If it does in this way, it can control that engine brake by engine regeneration control becomes large too much, and it can prevent decelerating suddenly against a driver's will.

  In this case, as in claim 5, when the remaining battery information is greater than or equal to the threshold during vehicle deceleration, the rotation speed of the output shaft and the gear mechanism used in the first engine regeneration control (the one with the smaller gear ratio) is used. The engine speed that can be increased by the first engine regeneration control based on the gear ratio of the gear mechanism), and when the engine speed that can be increased is higher than a predetermined restart rotational speed lower limit value, 1 engine regeneration control may be executed. In this way, the first engine regeneration control is performed when the engine rotational speed that can be increased by the first engine regeneration control is higher than the restart rotational speed lower limit value (lower limit value of the restartable rotational speed region). Therefore, it can be determined that the engine rotational speed can be increased to a restartable rotational speed range, the first engine regeneration control can be executed, and it is possible to avoid performing the first engine regeneration control in vain. .

  In addition, as described in claim 6, after the first engine regeneration control is executed, the power of the axle is transmitted to the engine via the gear mechanism having the larger gear ratio of the engine side gear mechanism and the motor side gear mechanism. As described above, the control may be shifted to the second engine regeneration control in which the clutch is controlled to drive the engine. If it does in this way, after raising an engine speed to the revolving speed field which can be restarted by the 1st engine regeneration control, it will shift to the 2nd engine regeneration control, and an engine speed will be carried out by the 2nd engine regeneration control. Can be maintained in the restartable rotation speed region, and the period during which the engine rotation speed can be maintained in the restartable rotation speed region can be lengthened. In addition, the gear mechanism with the larger gear ratio is used to shift to the second engine regeneration control after decelerating to some extent by the engine brake by the first engine regeneration control using the gear mechanism with the smaller gear ratio. Even if the second engine regenerative control is performed, it is possible to prevent the engine brake due to the engine regenerative control from becoming excessively large, and to prevent sudden deceleration against the driver's will.

  In this case, as in the seventh aspect, when the engine speed becomes higher than a predetermined restart speed lower limit value by the first engine regeneration control, the output shaft speed and the second engine regeneration control. The engine speed that can be increased by the second engine regeneration control is calculated on the basis of the gear ratio of the gear mechanism (the gear mechanism having the larger gear ratio) that is used in the above, and the engine speed that can be increased When it is higher than the starting rotational speed upper limit value, the second engine regeneration control may be shifted to. In this way, when the engine rotation speed that can be increased by the second engine regeneration control is higher than the restart rotation speed upper limit value (the upper limit value of the restartable rotation speed region), the second engine regeneration control is performed. Therefore, it can be determined that the engine speed can be maintained in the restartable rotation speed region, and the second engine regeneration control can be shifted to avoid unnecessary execution of the second engine regeneration control. it can.

FIG. 1 is a diagram showing a schematic configuration of a drive system for a hybrid vehicle in Embodiment 1 of the present invention. FIG. 2 is a diagram illustrating control states of the clutch, the MG, and the engine in each operation mode of the regeneration control during deceleration according to the first embodiment. FIG. 3 is a diagram illustrating regeneration control during deceleration according to the first embodiment. FIG. 4 is a flowchart showing the flow of processing of the deceleration regeneration control routine of the first embodiment. FIG. 5 is a diagram illustrating control states of the clutch, the MG, and the engine in each operation mode of the regeneration control during deceleration according to the second embodiment. FIG. 6 is a diagram illustrating regeneration control during deceleration according to the second embodiment. FIG. 7 is a flowchart (No. 1) showing the flow of processing of the deceleration regeneration control routine of the second embodiment. FIG. 8 is a flowchart (No. 2) showing the flow of processing of the regeneration control routine during deceleration according to the second embodiment. FIG. 9 is a diagram showing a schematic configuration of a drive system for a hybrid vehicle in another embodiment.

  Hereinafter, some embodiments embodying the mode for carrying out the present invention will be described.

A first embodiment of the present invention will be described with reference to FIGS.
First, a schematic configuration of a hybrid vehicle drive system will be described with reference to FIG.

  The power transmission device 11 mounted on the hybrid vehicle includes an engine 12, a first motor generator (hereinafter referred to as “first MG”) 13, and a second motor generator (hereinafter referred to as “second MG”). ) 14, first engine input shaft 15, damper 16, second engine input shaft 17, motor input shaft 18, engine side drive gear 19 and driven gear 20, motor side drive gear 21 and driven gear 22, first clutch 23 The second clutch 24, the third clutch 25, the output shaft 26, the differential gear 27, and the like are provided, and the power (that is, the drive torque) generated by the engine 12, the first and second MGs 13 and 14 is transmitted to the axle 28. Thus, a driving force is generated in the driving wheel 29.

  The first and second MGs 13 and 14 are connected to a battery 31 (storage battery) via an inverter 30, and the first and second MGs 13 and 14 exchange power with the battery 31 via the inverter 30. ing. The engine 12 is an internal combustion engine, and the first and second MGs 13 and 14 are electric motors that are rotated by the electric power of the battery 31, and the power transmission device 11 (specifically, the motor input shaft 18 for the first MG 13). In the case of the second MG 14, it is also a generator that generates power using the shaft torque transmitted from the output shaft 26) and charges the battery 31.

  Power generated by the engine 12 is input to a first engine input shaft 15 extending from the engine 12. The first engine input shaft 15 functions as a shaft for transmitting power input from the engine 12. A known torsion damper 16 is attached to the end of the first engine input shaft 15 opposite to the engine 12.

  A second engine input shaft 17 is coaxially attached to the first engine input shaft 15 on the opposite side of the damper 16 from the first engine input shaft 15. Therefore, the second engine input shaft 17 transmits the power of the first engine input shaft 15 via the damper 16.

  An engine-side drive gear 19 is attached to the second engine input shaft 17, and the drive gear 19 rotates together with the second engine input shaft 17.

  In addition, the power generated by the first MG 13 is input to the motor input shaft 18 extending from the first MG 13. The motor input shaft 18 functions as a shaft for transmitting power input from the first MG 13.

  A motor-side drive gear 21 is attached to the motor input shaft 18, and the drive gear 21 rotates together with the motor input shaft 18.

  The second engine input shaft 17 and the motor input shaft 18 are arranged in parallel and coaxial with each other. The first clutch 23 is a clutch mechanism that is provided between the second engine input shaft 17 and the motor input shaft 18 and intermittently connects and disconnects the second engine input shaft 17 and the motor input shaft 18. As the first clutch 23, a wet clutch may be employed, or a dry clutch may be employed.

  Also, the power generated by the second MG 14 is input to the output shaft 26 extending from the second MG 14. The output shaft 26 is disposed on the side of the first engine input shaft 15, the second engine input shaft 17, and the motor input shaft 18 in parallel to the input shafts 15, 17, 18, and includes a differential gear 27, an axle 28. Power to transmit to etc. is output.

  The engine-side driven gear 20 meshes with the drive gear 19 and is rotatably supported by the output shaft 26. The third clutch 25 is a clutch mechanism that is attached to the output shaft 26 and that intermittently connects the output shaft 26 and the driven gear 20. As the third clutch 25, a wet clutch may be employed, a dry clutch may be employed, or a meshing clutch such as a synchro mechanism may be employed.

  The motor-side driven gear 22 meshes with the drive gear 21 and is rotatably supported by the output shaft 26. The second clutch 24 is a clutch mechanism that is attached to the output shaft 26 and that intermittently connects the output shaft 26 and the driven gear 22. As the second clutch 24, a wet clutch may be employed, a dry clutch may be employed, or a meshing clutch such as a synchro mechanism may be employed.

  The power of the output shaft 26 is transmitted to the drive wheels 29 via a final gear and a differential gear 27 and an axle 28 (not shown).

  By connecting the third clutch 25, power is transmitted between the output shaft 26 and the engine-side driven gear 20. Accordingly, power is transmitted between the second engine input shaft 17 and the output shaft 26 (not via the motor input shaft 18) via the engine-side drive gear 19, driven gear 20, and third clutch 25. Conversely, when the third clutch 25 is disengaged, power transmission is not performed between the second engine input shaft 17 and the output shaft 26. The engine-side drive gear 19 and the driven gear 20 constitute a high gear mechanism 32 (corresponding to an example of an engine-side gear mechanism). The reduction ratio (gear ratio) of the high gear mechanism 32 is the smallest among the reduction ratios of the gear mechanisms provided in the power transmission device 11.

  Further, by connecting the second clutch 24, power transmission is performed between the output shaft 26 and the driven gear 22 on the motor side. Accordingly, power is transmitted between the motor input shaft 18 and the output shaft 26 (not through the engine input shafts 15 and 17) via the motor-side drive gear 21, driven gear 22, and second clutch 24. Conversely, when the second clutch 24 is disengaged, power transmission is not performed between the motor input shaft 18 and the output shaft 26. The motor-side drive gear 21 and the driven gear 22 constitute a low gear mechanism 33 (corresponding to an example of a motor-side gear mechanism). The reduction gear ratio (gear ratio) of the low gear mechanism 33 is the largest of the reduction gear ratios of the gear mechanism provided in the power transmission device 11. Accordingly, the reduction ratio of the low gear mechanism 33 is larger than the reduction ratio of the high gear mechanism 32.

  In this power transmission device 11, the gear mechanism closer to the engine 12 is the high gear mechanism 32 and the gear mechanism closer to the first MG 13 is the low gear mechanism, both when viewed from the power transmission path and from the arrangement. 33.

  Further, when the first clutch 23 is connected, power is transmitted between the second engine input shaft 17 and the motor input shaft 18 via the first clutch 23, and when the first clutch 23 is disconnected. The power is not transmitted between the second engine input shaft 17 and the motor input shaft 18.

  When the first clutch 23 is connected, power is always transmitted from the position where the drive gear 19 is provided on the second engine input shaft 17 to the position where the drive gear 21 is provided on the motor input shaft 18. Is possible. In other words, no clutch other than the first clutch 23 is interposed in the power transmission path from the position where the engine-side drive gear 19 is provided on the input shafts 15, 17, 18 to the motor-side drive gear 21. As a result, the number of clutches can be reduced as compared with the conventional case, and the power transmission device 11 can be downsized.

  Further, the distance from the engine 12 to the engine-side drive gear 19 is reduced by arranging the first clutch 23 and the engine-side drive gear 19 between the motor-side drive gear 21 and the engine 12. As a result, the resistance against the torsional vibration of the engine input shafts 15 and 17 can be kept high.

  Further, by arranging the first clutch 23 and the motor-side drive gear 21 at a position between the engine-side drive gear 19 and the first MG 13, from the first MG 13 to the motor-side drive gear 21. As a result, the resistance against torsional vibration of the motor input shaft 18 can be kept high.

  The ECU 34 (electronic control circuit) is configured mainly with a microcomputer, and based on various physical quantities acquired in the vehicle, the first and second MGs 13 and 14 are driven / not driven, and the first By controlling the connection / disconnection of the first to third clutches 23 to 25, the transmission path and the reduction ratio of the power generated by the engine 12 and the first MG 13 are controlled.

  The ECU 34 includes a vehicle speed detected by a vehicle speed sensor (not shown), an accelerator opening (accelerator operation amount) detected by an accelerator sensor (not shown), and a battery 31 detected by a battery monitoring device (not shown). Various signals such as an SOC (State Of Charge) representing a state of charge and an engine speed detected by a crank angle sensor (not shown) are input.

  The ECU 34 switches connection / disconnection of the first to third clutches 23 to 25 based on these input signals. Specifically, the ECU 34 controls the operation of actuators provided for the clutches 23 to 25 (for example, actuators that generate hydraulic pressure for clutch engagement / disengagement), thereby connecting / disconnecting the clutches 23 to 25. Switch cutting individually.

  By such control of the clutches 23 to 25 by the ECU 34, the power generated by the first MG 13 is transmitted to the driving wheel 29 via the low gear mechanism 33 or to the driving wheel 29 via the high gear mechanism 32. It is also possible to be done. Further, the power generated by the engine 12 can be transmitted to the drive wheels 29 via the low gear mechanism 33 or can be transmitted to the drive wheels 29 via the high gear mechanism 32.

  Further, in the first embodiment, the ECU 34 executes a deceleration-time regeneration control routine shown in FIG. 4 to be described later, so that the remaining battery information (remaining capacity of the battery 31 or information that changes in accordance with the remaining capacity of the battery 31) when the vehicle is decelerated. When the remaining battery level information is lower than a predetermined upper limit side threshold value (for example, charging target upper limit value), it is determined that the battery 31 can be charged, and the second MG 14 is driven by the power of the axle 28. MG regeneration control is performed to charge the battery 31 with the electric power generated by the second MG 14. On the other hand, if the battery remaining amount information is greater than or equal to the upper limit side threshold value, it is determined that the battery 31 cannot be charged much. Then, engine regeneration control is performed in which the engine 12 in the combustion stop state is rotationally driven by the power of the axle 28.

Specifically, as shown in FIGS. 2 and 3, when the vehicle is decelerated, the SOC of the battery 31 is detected as the remaining battery level information (for example, the SOC of the battery 31 detected by the battery monitoring device is read). Here, the SOC of the battery 31 is defined by the following equation, for example.
SOC = remaining capacity / full charge capacity x 100

  (a) When the SOC of the battery 31 is lower than the upper threshold value, it is determined that the battery 31 can be charged, and the operation mode is set to the MG regeneration mode. In this MG regeneration mode, all of the first to third clutches 23 to 25 are disconnected, and the second MG 14 is rotationally driven by the power of the output shaft 26 that is rotationally driven by the power of the axle 28, thereby causing the second MG 14 to rotate. By executing the MG regenerative control for charging the battery 31 with the electric power generated in the above, the kinetic energy of the vehicle is converted into electric power by the second MG 14 and recovered in the battery 31.

  Thereafter, (b) when the SOC of the battery 31 becomes equal to or greater than the upper threshold value, it is determined that the battery 31 cannot be charged so much and the operation mode is set to the engine regeneration mode. In the engine regeneration mode, the clutches 23 to 25 are controlled so that the power of the axle 28 is transmitted to the engine 12 via the high gear mechanism 32 (the gear mechanism having the smaller gear ratio) (the first and second clutches 23). , 24 and the third clutch 25 are connected), and the engine regeneration control (first engine regeneration) for rotationally driving the engine 12 in the combustion stopped state by the power of the output shaft 26 that is rotationally driven by the power of the axle 28. By executing (control), the engine speed is raised to a speed range where the engine speed can be restarted when the vehicle is decelerated (an engine speed range where the engine 12 can be started only by restarting fuel injection and ignition).

  Thereafter, (c) when an acceleration request is generated and the operation mode is set to the acceleration mode, the fuel injection and ignition of the engine 12 are restarted, the engine 12 is restarted promptly, and the power of the engine 12 is The clutches 23 to 25 are controlled so that the power of the first and second MGs 13 and 14 is transmitted to the axle 28 (the first and second clutches 23 and 24 are connected and the third clutch 25 is disconnected). To accelerate the vehicle.

  Hereinafter, the processing contents of the deceleration regeneration control routine shown in FIG. 4 executed by the ECU 34 in the first embodiment will be described.

  The deceleration-time regeneration control routine shown in FIG. 4 is repeatedly executed at a predetermined cycle during the power-on period of the ECU 34, and serves as a deceleration-time regeneration control means in the claims. When this routine is started, first, at step 101, it is determined whether the vehicle is decelerating, for example, whether the difference in vehicle speed (difference between the current value of the vehicle speed and the previous value) is equal to or less than a predetermined value. Alternatively, the determination is made based on whether or not the difference in accelerator opening (the difference between the current value and the previous value of the accelerator opening) is equal to or less than a predetermined value.

  If it is determined in step 101 that the vehicle is not decelerating, this routine is terminated without executing the processing from step 102 onward.

  On the other hand, if it is determined in step 101 that the vehicle is decelerating, the process proceeds to step 102 to determine whether or not the SOC of the battery 31 is lower than the upper threshold value. Here, the upper limit side threshold value is, for example, the charging target upper limit value of the battery 31, and is set to a value slightly smaller than the full charge capacity of the battery 31.

  If it is determined in step 102 that the SOC of the battery 31 is lower than the upper threshold value, it is determined that the battery 31 can be charged, the process proceeds to step 103, and the operation mode is set to the MG regeneration mode. .

  In this MG regeneration mode, all of the first to third clutches 23 to 25 are disconnected, and the second MG 14 is rotationally driven by the power of the output shaft 26 that is rotationally driven by the power of the axle 28, thereby causing the second MG 14 to rotate. By executing the MG regenerative control for charging the battery 31 with the electric power generated in the above, the kinetic energy of the vehicle is converted into electric power by the second MG 14 and recovered in the battery 31 (steps 104 and 105).

  Thereafter, the process proceeds to step 106, where it is determined whether or not the SOC of the battery 31 is equal to or higher than the upper limit threshold value. When it is determined that the SOC of the battery 31 is lower than the upper limit threshold value, the process returns to step 104 above. , MG regeneration control is continued.

On the other hand, if it is determined in step 102 or step 106 that the SOC of the battery 31 is greater than or equal to the upper limit threshold value, it is determined that the battery 31 cannot be charged much, and the process proceeds to step 107, where the current output shaft The engine speed Nemax1 that can be increased by the engine regeneration control is calculated by the following equation using the rotational speed Nout of 26 and the gear ratio Ghigh of the high gear mechanism 32 (the gear mechanism having the smaller gear ratio) used in the engine regeneration control. To do.
Nemax1 = Nout x (1 / Ghigh)

  The rotational speed Nout of the output shaft 26 may be detected by a rotational speed sensor or the like, or may be calculated from the vehicle speed (or the rotational speed of the axle 28).

  Thereafter, the routine proceeds to step 108, where it is determined whether or not the engine rotational speed Nemax1 that can be increased by engine regeneration control is higher than a predetermined restart rotational speed lower limit value (lower limit value of the restartable rotational speed region).

  If it is determined in step 108 that the engine rotational speed Nemax1 that can be increased by the engine regeneration control is higher than the restart rotational speed lower limit value, the rotational speed region in which the engine rotational speed Ne can be restarted by the engine regeneration control. If it is determined that the operation mode can be increased to step 109, the process proceeds to step 109 to set the operation mode to the engine regeneration mode.

  In the engine regeneration mode, the clutches 23 to 25 are controlled so that the power of the axle 28 is transmitted to the engine 12 via the high gear mechanism 32 (the gear mechanism having the smaller gear ratio) (the first and second clutches 23). , 24 and the third clutch 25 are connected), and engine regeneration control is executed to rotationally drive the engine 12 in the combustion stopped state by the power of the output shaft 26 that is rotationally driven by the power of the axle 28 (step 110). , 111).

  Thereafter, the routine proceeds to step 112, where it is determined whether or not the engine rotational speed Ne detected by the crank angle sensor is higher than the restart rotational speed lower limit value, and it is determined that the engine rotational speed Ne is less than or equal to the restart rotational speed lower limit value. If it is determined that the engine regeneration control is continued, the engine regeneration control is continued. Thereafter, if it is determined in step 112 that the engine rotational speed Ne is higher than the restart rotational speed lower limit value, the engine regeneration control is performed. The routine is terminated when it is determined that the engine speed has been increased to a restartable speed range by the control.

  If it is determined in step 108 that the engine rotational speed Nemax1 that can be increased by the engine regeneration control is equal to or lower than the restart rotational speed lower limit value, the engine rotational speed Ne can be restarted by the engine regeneration control. It is determined that the speed cannot be increased to the speed range, and this routine is terminated without executing the engine regeneration control.

  In the first embodiment described above, if the SOC of the battery 31 is lower than the upper limit side threshold during vehicle deceleration, it is determined that the battery 31 can be charged, and the second MG 14 is driven by the power of the axle 28. Since the MG regeneration control for charging the battery 31 with the electric power generated by the second MG 14 is performed by rotating the vehicle, the kinetic energy of the vehicle is converted into the electric power by the second MG 14 and recovered into the battery 31. be able to. On the other hand, when the SOC of the battery 31 is equal to or higher than the upper limit threshold value, it is determined that the battery 31 cannot be charged much, and engine regeneration control is performed to rotationally drive the engine 12 in the combustion stopped state with the power of the axle 28. Since it did in this way, when decelerating a vehicle, an engine speed can be pulled up to the revolving speed area which can be restarted. As a result, the engine 12 can be restarted quickly only by restarting fuel injection and ignition without cranking the engine 12 with MG or the like during acceleration after deceleration of the vehicle. Energy can be used effectively as energy for restarting the engine.

  In the first embodiment, when the MG regeneration control is performed, the first to third clutches 23 to 25 are all disconnected and the second MG 14 performs the MG regeneration control. The engine 12 is disconnected from the power transmission path for transmitting the power to the second MG 14, and the MG regeneration control can be performed in a state in which the energy loss due to the drag of the engine 12 is eliminated. Can be regenerated.

  Further, in the first embodiment, when the engine regeneration control is performed, the clutches 23 to 25 are set so that the power of the axle 28 is transmitted to the engine 12 via the high gear mechanism 32 (the gear mechanism having the smaller gear ratio). Since the engine regenerative control is performed by controlling, it is possible to suppress an excessive increase in engine brake due to the engine regenerative control and to prevent sudden deceleration against the driver's will.

  At this time, in the first embodiment, when the SOC of the battery 31 is equal to or higher than the upper threshold when the vehicle is decelerated, the rotational speed Nout of the output shaft 26 and the high gear mechanism 32 used for engine regeneration control (the one with the smaller gear ratio). The engine speed Nemax1 that can be increased by engine regeneration control is calculated based on the gear ratio Ghigh of the gear mechanism), and when the engine speed Nemax1 that can be increased is higher than the restart rotational speed lower limit value, the engine regeneration control is performed. Therefore, it is determined that the engine speed can be increased to a restartable speed range, and the engine regeneration control is executed. Therefore, it is possible to avoid performing the engine regeneration control in vain.

  Next, a second embodiment of the present invention will be described with reference to FIGS. However, description of substantially the same parts as those in the first embodiment will be omitted or simplified, and different parts from the first embodiment will be mainly described.

  In the second embodiment, the ECU 34 executes a regenerative control routine during deceleration shown in FIGS. 7 and 8 to be described later, and when the remaining battery information is equal to or greater than the upper threshold when the vehicle is decelerating, first, the high gear mechanism. The first engine regenerative control for rotating the engine 12 is executed by controlling the clutches 23 to 25 so that the power of the axle 28 is transmitted to the engine 12 via the gear 32 (the gear mechanism having the smaller gear ratio). Then, the second engine that rotates the engine 12 by controlling the clutches 23 to 25 so as to transmit the power of the axle 28 to the engine 12 via the low gear mechanism 33 (the gear mechanism having the larger gear ratio). Transition to regenerative control.

  Specifically, as shown in FIGS. 5 and 6, when the vehicle decelerates, the SOC of the battery 31 is detected. (A) When the SOC of the battery 31 is lower than the upper limit side threshold value, the battery 31 is charged. The operation mode is determined to be possible and the operation mode is set to the MG regeneration mode. In this MG regeneration mode, all of the first to third clutches 23 to 25 are disconnected, and the second MG 14 is rotationally driven by the power of the output shaft 26 that is rotationally driven by the power of the axle 28, thereby causing the second MG 14 to rotate. By executing the MG regenerative control for charging the battery 31 with the electric power generated in the above, the kinetic energy of the vehicle is converted into electric power by the second MG 14 and recovered in the battery 31.

  Thereafter, (b1) when the SOC of the battery 31 is equal to or greater than the upper limit threshold, it is determined that the battery 31 cannot be charged so much and the operation mode is set to the first engine regeneration mode. In the first engine regeneration mode, the clutches 23 to 25 are controlled so that the power of the axle 28 is transmitted to the engine 12 via the high gear mechanism 32 (the gear mechanism having the smaller gear ratio) (first and second). First clutch regenerative control in which the engine 12 in the combustion stop state is driven to rotate by the power of the output shaft 26 rotated by the power of the axle 28. By executing this, when the vehicle decelerates, the engine rotation speed is increased to a rotation speed region where restart is possible.

  Thereafter, (b2) when the engine rotation speed becomes higher than the restart rotation speed lower limit value, the operation mode is set to the second engine regeneration mode. In the second engine regeneration mode, the clutches 23 to 25 are controlled so that the power of the axle 28 is transmitted to the engine 12 via the low gear mechanism 33 (the gear mechanism having the larger gear ratio) (the first clutch 23). Or the second clutch 24 is connected and the third clutch 25 is disconnected), and the engine 12 in the combustion stop state is driven to rotate by the power of the output shaft 26 that is rotated by the power of the axle 28. By executing the second engine regenerative control, the engine speed is maintained in a restartable speed range when the vehicle is decelerated.

  Hereinafter, the processing contents of the deceleration regeneration control routine shown in FIGS. 7 and 8 executed by the ECU 34 in the second embodiment will be described.

  In the deceleration regeneration control routine shown in FIGS. 7 and 8, first, at step 201, it is determined whether or not the vehicle is decelerating. If it is determined that the vehicle is decelerating, the routine proceeds to step 202. It is determined whether the SOC of the battery 31 is lower than the upper limit side threshold value. If it is determined in step 202 that the SOC of the battery 31 is lower than the upper threshold value, it is determined that the battery 31 can be charged, the process proceeds to step 203, and the operation mode is set to the MG regeneration mode. .

  In this MG regeneration mode, all of the first to third clutches 23 to 25 are disconnected, and the second MG 14 is rotationally driven by the power of the output shaft 26 that is rotationally driven by the power of the axle 28, thereby causing the second MG 14 to rotate. By executing the MG regenerative control for charging the battery 31 with the electric power generated in step 504, the kinetic energy of the vehicle is converted into electric power by the second MG 14 and recovered in the battery 31 (steps 204 and 205).

  Thereafter, the process proceeds to step 206, where it is determined whether or not the SOC of the battery 31 is greater than or equal to the upper limit threshold value. If it is determined that the SOC of the battery 31 is lower than the upper limit threshold value, the process returns to step 204 above. , MG regeneration control is continued.

On the other hand, if it is determined in step 202 or step 206 that the SOC of the battery 31 is equal to or higher than the upper limit threshold value, it is determined that the battery 31 cannot be charged much, and the process proceeds to step 207, where the current output shaft The engine rotational speed that can be increased by the first engine regeneration control using the rotational speed Nout of 26 and the gear ratio Ghigh of the high gear mechanism 32 (the gear mechanism having the smaller gear ratio) used in the first engine regeneration control. Nemax1 is calculated by the following equation.
Nemax1 = Nout x (1 / Ghigh)

  Thereafter, the routine proceeds to step 208, where it is determined whether or not the engine rotational speed Nemax1 that can be increased by the first engine regeneration control is higher than a predetermined restart rotational speed lower limit value (lower limit value of the restartable rotational speed region). judge.

  If it is determined in step 208 that the engine rotational speed Nemax1 that can be increased by the first engine regeneration control is higher than the restart rotational speed lower limit value, the engine rotational speed Ne is restarted by the first engine regeneration control. If it is determined that the engine speed can be increased to the startable rotation speed region, the process proceeds to step 209 to set the operation mode to the first engine regeneration mode.

  In the first engine regeneration mode, the clutches 23 to 25 are controlled so that the power of the axle 28 is transmitted to the engine 12 via the high gear mechanism 32 (the gear mechanism having the smaller gear ratio) (first and second). First clutch regenerative control in which the engine 12 in the combustion stop state is driven to rotate by the power of the output shaft 26 rotated by the power of the axle 28. Are executed (steps 210 and 211).

Thereafter, the routine proceeds to step 212, where it is determined whether or not the engine rotational speed Ne detected by the crank angle sensor is higher than the restart rotational speed lower limit value, and it is determined that the engine rotational speed Ne is less than or equal to the restart rotational speed lower limit value. If it is determined that the engine speed is returned to step 210 and the first engine regeneration control is continued, and then in step 212, it is determined that the engine speed is higher than the restart speed lower limit, It is determined that the engine speed has been increased to a restartable speed range by the first engine regeneration control, and the process proceeds to step 213 in FIG. 8, and the current rotational speed Nout of the output shaft 26 and the second engine regeneration control are performed. The engine speed which can be raised by the second engine regeneration control using the gear ratio Glow of the low gear mechanism 33 (the gear mechanism having the larger gear ratio) used in FIG. The speed Nemax2 is calculated by the following equation.
Nemax2 = Nout x (1 / Glow)

  After this, the routine proceeds to step 214, where it is determined whether or not the engine speed Nemax2 that can be increased by the second engine regeneration control is higher than a predetermined restart speed upper limit value (upper limit value of the restartable speed range). judge.

  If it is determined in step 214 that the engine rotational speed Nemax2 that can be increased by the second engine regeneration control is higher than the restart rotational speed upper limit value, the engine rotational speed Ne is restarted by the second engine regeneration control. If it is determined that the engine speed can be maintained in the startable rotation speed region, the process proceeds to step 215, and the operation mode is set to the second engine regeneration mode.

  In the second engine regeneration mode, the clutches 23 to 25 are controlled so that the power of the axle 28 is transmitted to the engine 12 via the low gear mechanism 33 (the gear mechanism having the larger gear ratio) (the first clutch 23). Or the second clutch 24 is connected and the third clutch 25 is disconnected), and the engine 12 in the combustion stop state is driven to rotate by the power of the output shaft 26 that is rotated by the power of the axle 28. The second engine regeneration control is performed (steps 216 and 217).

  Specifically, when the engine rotational speed Ne is higher than the restart rotational speed lower limit value and less than or equal to the restart rotational speed upper limit value (restart rotational speed lower limit value <Ne ≤ restart rotational speed upper limit value), The first and second clutches 23 and 24 are connected, the third clutch 25 is disconnected, and the engine rotational speed Ne is maintained in a restartable rotational speed region. When the engine rotational speed Ne is higher than the restart rotational speed upper limit value, the first clutch 23 is in a half-clutch state (sliding state), the second clutch 24 is connected, and the third clutch 25 is disconnected. Thus, the engine speed Ne is lowered to a restartable speed range.

  Thereafter, the routine proceeds to step 218, where it is determined whether or not the engine rotational speed Ne detected by the crank angle sensor is equal to or lower than the restart rotational speed lower limit value, and if the engine rotational speed Ne is higher than the restart rotational speed lower limit value. If it is determined, the process returns to step 216 and the second engine regeneration control is continued. Thereafter, if it is determined in step 218 that the engine speed is equal to or lower than the restart speed lower limit value. This routine is terminated.

  When it is determined in step 214 that the engine rotational speed Nemax2 that can be increased by the second engine regeneration control is equal to or lower than the restart rotational speed upper limit value, the engine rotational speed Ne is performed by the second engine regeneration control. Is determined to be difficult to maintain in the restartable rotation speed region, and this routine is terminated without executing the second engine regeneration control.

  In the second embodiment described above, the respective clutches 23 to 25 are controlled to rotate the engine 12 so that the power of the axle 28 is transmitted to the engine 12 via the high gear mechanism 32 (the gear mechanism having the smaller gear ratio). After executing the first engine regeneration control to drive, the clutches 23 to 25 are controlled so that the power of the axle 28 is transmitted to the engine 12 via the low gear mechanism 33 (the gear mechanism having the larger gear ratio). Since the engine 12 is shifted to the second engine regeneration control for rotationally driving the engine 12, the second engine regeneration control is performed after raising the engine rotational speed Ne to the restartable rotational speed region by the first engine regeneration control. The engine rotational speed Ne can be maintained in the restartable rotational speed region by the second engine regeneration control, and the engine rotational speed Ne can be restarted. The period to maintain the dynamic possible rotational speed range can be increased. In addition, after decelerating to some extent by engine braking by the first engine regeneration control using the high gear mechanism 32 (the gear mechanism having the smaller gear ratio), the low gear mechanism 33 (gear) is shifted to the second engine regeneration control. Even if the second engine regenerative control using the gear mechanism having the larger ratio is executed, the engine brake caused by the engine regenerative control is prevented from becoming excessively large, and suddenly decelerates against the driver's will. Can be prevented.

  At this time, in the second embodiment, when the engine rotational speed Ne becomes higher than the restart rotational speed lower limit value by the first engine regeneration control, the rotational speed Nout of the output shaft 26 and the second engine regeneration control are performed. The engine speed Nemax2 that can be increased by the second engine regeneration control is calculated based on the gear ratio of the low gear mechanism 33 (the gear mechanism having the larger gear ratio) to be used, and the engine speed Nemax2 that can be increased is calculated again. When it is higher than the starting rotational speed upper limit value, it is determined that the engine rotational speed Ne can be maintained in the restartable rotational speed region by the second engine regeneration control, and the process proceeds to the second engine regeneration control. Since it did in this way, it can avoid performing 2nd engine regeneration control uselessly.

  In each of the first and second embodiments, the SOC of the battery 31 is used as the battery remaining amount information. However, the present invention is not limited to this. For example, the remaining capacity of the battery 31 or the voltage of the battery 31 may be used. You may make it use as.

  In addition, the present invention is not limited to the system including the power transmission device having the configuration shown in FIG. 1, and is applied to a system including a power transmission device having various configurations capable of transmitting engine power and MG power to the axle. For example, the present invention may be applied to a system including the power transmission device 35 shown in FIG. In the power transmission device 35, an MG 37 and a transmission 38 are arranged on a power transmission path for transmitting the power of the engine 36 to the output shaft 41, and a first clutch 39 is provided between the engine 36 and the MG 37. The second clutch 40 is provided between the transmission 38 and the transmission 38. The power of the output shaft 41 is transmitted to the drive wheels 44 via the differential gear 42 and the axle 43.

  DESCRIPTION OF SYMBOLS 11 ... Power transmission device, 12 ... Engine, 13, 14 ... MG, 15, 17 ... Engine input shaft, 18 ... Motor input shaft, 19 ... Drive gear, 20 ... Driven gear, 21 ... Drive gear, 22 ... Driven gear, 23 -25 ... clutch, 26 ... output shaft, 28 ... axle, 30 ... inverter, 31 ... battery, 32 ... high gear mechanism (engine side gear mechanism), 33 ... low gear mechanism (motor side gear mechanism), 34 ... ECU (during deceleration) Regenerative control means)

Claims (7)

In a control device for a vehicle drive system, comprising: a power transmission device capable of transmitting engine power and motor generator (hereinafter referred to as “MG”) power to a vehicle axle; and a battery for transmitting and receiving electric power to and from the MG.
When the vehicle decelerates, when the remaining capacity of the battery or information that changes in accordance with the remaining capacity (hereinafter referred to as “battery remaining amount information”) is lower than a predetermined threshold, the MG uses the power of the axle. MG regeneration control is performed to charge the battery with the electric power generated by the MG, and when the battery remaining amount information is equal to or greater than the threshold value, engine regeneration control is performed to drive the engine with the power of the axle. A control device for a vehicle drive system, comprising: a deceleration regeneration control means to be executed. The MG includes a first MG and a second MG,
The power transmission device receives an engine input shaft that transmits the power of the engine, a motor input shaft that transmits the power of the first MG, and the power of the second MG and transmits the power to the axle. An output shaft for outputting power for the engine, an engine side gear mechanism for transmitting the power of the engine input shaft to the output shaft without passing through the motor input shaft, and the power of the motor input shaft for the engine input shaft A motor-side gear mechanism for transmitting to the output shaft without going through, a first clutch for intermittently transmitting power between the engine input shaft and the motor input shaft, the motor-side gear mechanism and the output A second clutch that interrupts power transmission between the shaft and a third clutch that interrupts power transmission between the engine side gear mechanism and the output shaft, the first clutch being connected The A control device for a vehicle drive system according to claim 1 for the in case the engine side gear mechanism and the motor side gear mechanism is characterized by being configured to allow power transmission.   The deceleration regeneration control means disconnects at least the second clutch and the third clutch and performs the MG regeneration control with the second MG when performing the MG regeneration control. The control device for a vehicle drive system according to claim 2.   When the engine regeneration control is performed, the deceleration-time regeneration control means transmits the power of the axle to the engine via a gear mechanism having a smaller gear ratio between the engine side gear mechanism and the motor side gear mechanism. 4. The control device for a vehicle drive system according to claim 2, wherein first engine regenerative control for controlling each clutch so as to transmit and driving the engine is executed. 5.   The deceleration-time regeneration control means adjusts the rotation speed of the output shaft and the gear ratio of the gear mechanism used in the first engine regeneration control when the remaining battery information is greater than or equal to the threshold during deceleration of the vehicle. Based on the first engine regeneration control, the engine speed that can be increased is calculated, and when the engine speed that can be increased is higher than a predetermined restart rotational speed lower limit value, the first engine regeneration control is performed. The control device for a vehicle drive system according to claim 4, wherein the control device is executed.   The deceleration-time regeneration control means executes the first engine regeneration control, and then transmits the power of the axle via a gear mechanism having a larger gear ratio between the engine side gear mechanism and the motor side gear mechanism. 6. The control device for a vehicle drive system according to claim 4, wherein the control is shifted to second engine regenerative control for driving the engine by controlling each clutch so as to transmit to the engine.   The deceleration-time regeneration control means determines the output shaft rotational speed and the second engine when the engine rotational speed becomes higher than a predetermined restart rotational speed lower limit value by the first engine regeneration control. Based on the gear ratio of the gear mechanism used in the regenerative control, the engine rotational speed that can be increased by the second engine regenerative control is calculated, and the engine rotational speed that can be increased is higher than a predetermined restart rotational speed upper limit value. The vehicle drive system control device according to claim 6, wherein the control unit shifts to the second engine regenerative control when it is high.

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