JP6052092B2 - Hybrid vehicle drive device - Google Patents

Description

  The present invention relates to a hybrid vehicle drive device.

  As a conventional hybrid vehicle drive device, for example, Patent Document 1 discloses a hybrid vehicle that switches between a motor use travel mode and an engine use travel mode in accordance with a driving range defined by a vehicle speed, an accelerator opening, and a battery charge state. A control apparatus is disclosed.

Japanese Patent No. 4915233

  By the way, the control device for a hybrid vehicle described in the above-mentioned Patent Document 1 has a motor with respect to a change in the accelerator opening when the motor use travel region suddenly becomes narrow due to a slight difference in vehicle speed. There is a possibility that the use travel mode (rotary machine drive) and the engine use travel mode (engine drive) are frequently switched to cause hunting.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a hybrid vehicle drive device that can suppress hunting caused by switching between engine drive and rotary machine drive.

  A drive device for a hybrid vehicle of the present invention includes an engine and a rotating machine, and stops driving the engine and the engine that travels using the engine as a power source according to an operation region determined based on a vehicle speed and a required driving force. The rotating machine drive that travels using the rotating machine as a power source can be switched, and the narrower the required driving force with respect to the vehicle speed in the operation region that is driven by the rotating machine, the narrower the engine driving and the rotating machine at the vehicle speed. The switching hysteresis with the drive is increased.

  In the hybrid vehicle drive device according to the present invention, for example, the switching hysteresis is increased as the required driving force width in the operation region for rotating machine driving is narrowed, so that frequent switching between rotating machine driving and engine driving is suppressed. Thus, hunting due to switching between engine driving and rotating machine driving can be suppressed.

FIG. 1 is a skeleton diagram of a vehicle according to the first embodiment. FIG. 2 is an input / output relationship diagram of the vehicle according to the embodiment. FIG. 3 is a diagram illustrating an operation engagement table of the hybrid vehicle drive device according to the first embodiment. FIG. 4 is a collinear diagram related to the single motor EV mode. FIG. 5 is a collinear diagram related to the both-motor EV mode. FIG. 6 is a collinear diagram related to the HV low mode. FIG. 7 is a collinear diagram related to the HV high mode. FIG. 8 is a diagram illustrating an example of a map according to mode selection according to the first embodiment. FIG. 9 is a flowchart illustrating an example of control in the hybrid vehicle drive device of the first embodiment. FIG. 10 is a diagram illustrating an example of a map related to the required driving force hysteresis of the first embodiment. FIG. 11 is a time chart illustrating an example of an operation in the hybrid vehicle drive device of the first embodiment. FIG. 12 is a skeleton diagram of the vehicle according to the second embodiment. FIG. 13 is an alignment chart according to the HV traveling mode. FIG. 14 is a collinear diagram related to the EV travel mode.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited by this embodiment. In addition, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art or those that are substantially the same.

[Embodiment 1]
FIG. 1 is a skeleton diagram of a vehicle according to the first embodiment. FIG. 2 is an input / output relationship diagram of the vehicle according to the embodiment. FIG. 3 is a diagram illustrating an operation engagement table of the hybrid vehicle drive device according to the first embodiment. FIG. 4 is a collinear diagram related to the single motor EV mode. FIG. 5 is a collinear diagram related to the both-motor EV mode. FIG. 6 is a collinear diagram related to the HV low mode. FIG. 7 is a collinear diagram related to the HV high mode. FIG. 8 is a diagram illustrating an example of a map according to mode selection according to the first embodiment. FIG. 9 is a flowchart illustrating an example of control in the hybrid vehicle drive device of the first embodiment. FIG. 10 is a diagram illustrating an example of a map related to the required driving force hysteresis of the first embodiment. FIG. 11 is a time chart illustrating an example of an operation in the hybrid vehicle drive device of the first embodiment.

  As shown in FIG. 1, the vehicle 100 according to the present embodiment is a hybrid (HV) vehicle having an engine 1, a first rotating machine MG1, and a second rotating machine MG2 as power sources. Vehicle 100 may be a plug-in hybrid (PHV) vehicle that can be charged by an external power source. As shown in FIGS. 1 and 2, the vehicle 100 includes an engine 1, a first planetary gear mechanism 10, a second planetary gear mechanism 20, a first rotating machine MG1, a second rotating machine MG2, a clutch CL1, a brake BK1, and an HV_ECU 50. The MG_ECU 60 and the engine_ECU 70 are included.

  Further, the hybrid vehicle drive device 1-1 according to the present embodiment includes the engine 1, the first planetary gear mechanism 10, the second planetary gear mechanism 20, the clutch CL1, and the brake BK1. The hybrid vehicle drive device 1-1 may further include a control device such as each ECU 50, 60, 70 or the like. Further, the hybrid vehicle drive device 1-1 may include a first rotating machine MG1 and a second rotating machine MG2. The hybrid vehicle drive device 1-1 can be applied to an FF (front engine front wheel drive) vehicle, an RR (rear engine rear wheel drive) vehicle, or the like. The hybrid vehicle drive device 1-1 is mounted on the vehicle 100 such that the axial direction is the vehicle width direction, for example.

  The hybrid vehicle drive device 1-1 according to the present embodiment includes a first planetary gear mechanism 10, a clutch CL1, and a brake BK1, and a transmission unit (transmission mechanism) 40 is configured. Further, the hybrid vehicle drive device 1-1 includes the second planetary gear mechanism 20, and a differential portion 41 is configured. The clutch CL1 and the brake BK1 are engagement devices that change the speed of the first planetary gear mechanism 10. The hybrid vehicle drive device 1-1 includes the engine 1, a transmission unit 40, a differential unit 41, a clutch CL1, and a brake BK1, and the clutch CL1 and the brake BK1 form an electrically continuously variable transmission state. In the hybrid vehicle drive device 1-1, the transmission unit 40 and the first rotating machine MG <b> 1 are arranged on the same shaft as the output shaft of the engine 1, and the second rotating machine MG <b> 2 is a multi-axis arrangement.

  The engine 1 which is an engine converts the combustion energy of the fuel into a rotational motion of the output shaft and outputs it. The output shaft of the engine 1 is connected to the input shaft 2. The input shaft 2 is an input shaft of the power transmission device. The power transmission device includes a first rotating machine MG1, a second rotating machine MG2, a clutch CL1, a brake BK1, a differential device 30 and the like. The input shaft 2 is arranged coaxially with the output shaft of the engine 1 and on an extension line of the output shaft. The input shaft 2 is connected to the first carrier 14 of the first planetary gear mechanism 10.

  The speed change part 40 including the first planetary gear mechanism 10 is connected to the engine 1 and is changed by the engaging device (clutch CL1, brake BK1). The transmission unit 40 is connected to the first carrier 14 as an input element of the engine 1. The transmission unit 40 is capable of shifting and outputting the rotation of the engine 1. The first planetary gear mechanism 10 constituting the transmission unit 40 is an input-side differential mechanism that is disposed closer to the engine 1 than the second planetary gear mechanism 20. Here, the first planetary gear mechanism 10 is a single pinion type and includes a first sun gear 11, a first pinion gear 12, a first ring gear 13, and a first carrier 14.

  The first ring gear 13 is coaxial with the first sun gear 11 and is disposed on the radially outer side of the first sun gear 11. The first pinion gear 12 is disposed between the first sun gear 11 and the first ring gear 13 and meshes with the first sun gear 11 and the first ring gear 13, respectively. The first pinion gear 12 is rotatably supported by the first carrier 14. The first carrier 14 constituting the input element of the transmission unit 40 is connected to the input shaft 2 and rotates integrally with the input shaft 2. Therefore, the first pinion gear 12 can rotate (revolve) together with the input shaft 2 around the central axis of the input shaft 2 and is supported by the first carrier 14 and rotated around the central axis of the first pinion gear 12 ( Rotation) is possible.

  The clutch CL <b> 1 is a clutch device that can connect the first sun gear 11 and the first carrier 14. The clutch CL1 can be, for example, a friction engagement type clutch, but is not limited thereto, and a known clutch device such as a meshing type clutch may be used as the clutch CL1. For example, the clutch CL1 is controlled by hydraulic pressure to engage or disengage. The fully engaged clutch CL1 can connect the first sun gear 11 and the first carrier 14 and rotate the first sun gear 11 and the first carrier 14 together. The fully engaged clutch CL <b> 1 regulates the differential of the first planetary gear mechanism 10. On the other hand, the opened clutch CL1 disconnects the first sun gear 11 and the first carrier 14 and allows relative rotation between the first sun gear 11 and the first carrier 14. That is, the opened clutch CL1 allows the first planetary gear mechanism 10 to be differential. Note that the clutch CL1 can be controlled to a half-engaged state. The half-engaged clutch CL1 allows the first planetary gear mechanism 10 to be differentially operated.

  The brake BK1 is a brake device that can regulate the rotation of the first sun gear 11. The brake BK1 has an engagement element connected to the first sun gear 11, and an engagement element connected to the vehicle body side, for example, a case of the power transmission device. The brake BK1 may be a friction engagement type clutch device similar to the clutch CL1, but is not limited thereto, and a known clutch device such as a meshing type clutch may be used as the brake BK1. The brake BK1 is engaged or released by being controlled by, for example, hydraulic pressure. The fully engaged brake BK1 connects the first sun gear 11 and the vehicle body side and can regulate the rotation of the first sun gear 11. On the other hand, the released brake BK1 separates the first sun gear 11 from the vehicle body side and allows the first sun gear 11 to rotate. The brake BK1 can be controlled to be in a half-engaged state. The half-engaged brake BK1 allows the first sun gear 11 to rotate.

  The second planetary gear mechanism 20 of the present embodiment is mounted on the vehicle 100 as a differential part 41 that connects the transmission unit 40 including the first planetary gear mechanism 10 and the drive wheels 32. The second planetary gear mechanism 20 is an output-side differential mechanism that is disposed closer to the drive wheel 32 than the first planetary gear mechanism 10. The second planetary gear mechanism 20 is a single pinion type and includes a second sun gear 21, a second pinion gear 22, a second ring gear 23, and a second carrier 24. The second planetary gear mechanism 20 is disposed coaxially with the first planetary gear mechanism 10 and faces the engine 1 with the first planetary gear mechanism 10 interposed therebetween.

  The second ring gear 23 is coaxial with the second sun gear 21 and is disposed on the radially outer side of the second sun gear 21. The second pinion gear 22 is disposed between the second sun gear 21 and the second ring gear 23 and meshes with the second sun gear 21 and the second ring gear 23, respectively. The second pinion gear 22 is rotatably supported by the second carrier 24. The second carrier 24 is connected to the first ring gear 13 and rotates integrally with the first ring gear 13. The second pinion gear 22 can rotate (revolve) around the central axis of the input shaft 2 together with the second carrier 24, and is supported by the second carrier 24 to rotate (rotate) around the central axis of the second pinion gear 22. It is possible. The first ring gear 13 described above is an output element of the first planetary gear mechanism 10 constituting the transmission unit 40, and outputs the rotation input from the engine 1 to the first planetary gear mechanism 10 to the second carrier 24. Can do. The second carrier 24 corresponds to the first rotating element connected to the output element of the first planetary gear mechanism 10.

  The second sun gear 21 is connected to the rotary shaft 33 of the first rotary machine MG1. The rotating shaft 33 of the first rotating machine MG1 is disposed coaxially with the input shaft 2 and rotates integrally with the second sun gear 21. The second sun gear 21 corresponds to the second rotating element connected to the first rotating machine MG1. A counter drive gear 25 is connected to the second ring gear 23. The counter drive gear 25 is an output gear that rotates integrally with the second ring gear 23. The second ring gear 23 corresponds to the third rotating element connected to the second rotating machine MG <b> 2 and the drive wheel 32. The second ring gear 23 is an output element that can output the rotation input from the first rotating machine MG <b> 1 or the first planetary gear mechanism 10 to the drive wheels 32.

  The counter drive gear 25 meshes with the counter driven gear 26. The counter driven gear 26 is connected to a drive pinion gear 28 via a counter shaft 27. The counter driven gear 26 and the drive pinion gear 28 rotate integrally. The counter driven gear 26 is engaged with a reduction gear 35. The reduction gear 35 is connected to the rotation shaft 34 of the second rotary machine MG2. That is, the rotation of the second rotating machine MG2 is transmitted to the counter driven gear 26 via the reduction gear 35. The reduction gear 35 has a smaller diameter than that of the counter driven gear 26, and reduces the rotation of the second rotary machine MG <b> 2 and transmits it to the counter driven gear 26.

  The drive pinion gear 28 meshes with the diffring gear 29 of the differential device 30. The differential device 30 is connected to drive wheels 32 via left and right drive shafts 31. The second ring gear 23 is connected to the drive wheel 32 via a counter drive gear 25, a counter driven gear 26, a drive pinion gear 28, a differential device 30 and a drive shaft 31. The second rotating machine MG2 is connected to a power transmission path between the second ring gear 23 and the drive wheels 32, and can transmit power to the second ring gear 23 and the drive wheels 32, respectively. .

  The first rotating machine MG1 and the second rotating machine MG2 each have a function as a motor (electric motor) and a function as a generator. The first rotary machine MG1 and the second rotary machine MG2 are connected to a battery via an inverter. The first rotating machine MG1 and the second rotating machine MG2 can convert the electric power supplied from the battery into mechanical power and output it, and are driven by the input power to convert the mechanical power into electric power. Can be converted. The electric power generated by the rotating machines MG1 and MG2 can be stored in the battery. As the first rotating machine MG1 and the second rotating machine MG2, for example, a three-phase AC synchronous motor generator can be used.

  In the vehicle 100 of the present embodiment, the brake BK1, the clutch CL1, the first planetary gear mechanism 10, the counter drive gear 25, the second planetary gear mechanism 20, and the first coaxially with the engine 1 in order from the side closer to the engine 1. A rotating machine MG1 is arranged. Moreover, the hybrid vehicle drive device 1-1 of the present embodiment is a multi-shaft type in which the input shaft 2 and the rotation shaft 34 of the second rotating machine MG2 are arranged on different axes.

  As shown in FIG. 2, vehicle 100 includes HV_ECU 50, MG_ECU 60, and engine_ECU 70. Each ECU 50, 60, 70 is an electronic control unit having a computer. The HV_ECU 50 has a function of integrally controlling the entire vehicle 100. MG_ECU 60 and engine_ECU 70 are electrically connected to HV_ECU 50.

  The MG_ECU 60 can control the first rotary machine MG1 and the second rotary machine MG2. For example, the MG_ECU 60 controls the output torque of the first rotating machine MG1 by adjusting a current value (hereinafter also referred to as “MG1 current”) supplied to the first rotating machine MG1, and the second rotation. The output torque of the second rotary machine MG2 can be controlled by adjusting the current value supplied to the machine MG2 (hereinafter also referred to as “MG2 current”).

  The engine_ECU 70 can control the engine 1. The engine_ECU 70 can, for example, control the opening of the electronic throttle valve of the engine 1, perform ignition control of the engine 1 by outputting an ignition signal, and perform fuel injection control on the engine 1. The engine_ECU 70 can control the output torque of the engine 1 by electronic throttle valve opening control, injection control, ignition control, and the like.

  The HV_ECU 50 is connected to a vehicle speed sensor, an accelerator opening sensor, an MG1 rotational speed sensor, an MG2 rotational speed sensor, an output shaft rotational speed sensor, a battery sensor, and the like. With these sensors, the HV_ECU 50 causes the vehicle speed, the accelerator opening, the rotation speed of the first rotating machine MG1 (hereinafter also referred to as “MG1 rotation speed”), and the rotation speed of the second rotating machine MG2 (hereinafter referred to as “MG2 rotation”). The number of rotations of the output shaft of the power transmission device, the battery state SOC, and the like can be acquired.

  The HV_ECU 50 can calculate a required driving force, a required power, a required torque, and the like for the vehicle 100 based on acquired information such as the vehicle speed and the accelerator opening. The HV_ECU 50 also describes the output torque of the first rotating machine MG1 (hereinafter also referred to as “MG1 torque”) and the output torque of the second rotating machine MG2 (hereinafter referred to as “MG2 torque”) based on the calculated request value. And the output torque of the engine 1 (hereinafter also referred to as “engine torque”). The HV_ECU 50 outputs the MG1 torque command value and the MG2 torque command value to the MG_ECU 60. Further, the HV_ECU 50 outputs an engine torque command value to the engine_ECU 70.

  The HV_ECU 50 controls the clutch CL1 and the brake BK1 based on a travel mode described later. The HV_ECU 50 outputs a command value for the supply hydraulic pressure (PbCL1) for the clutch CL1 and a command value for the supply hydraulic pressure (PbBK1) for the brake BK1. A hydraulic control device (not shown) controls the supply hydraulic pressure to the clutch CL1 and the brake BK1 according to the command values of the supply hydraulic pressures PbCL1 and PbBK1.

  FIG. 3 is a diagram showing an operation engagement table of the hybrid vehicle drive device 1-1 according to the present embodiment. The vehicle 100 can selectively execute hybrid (HV) traveling or EV traveling. The HV travel is a travel mode in which the vehicle 100 travels using the engine 1 as a power source. In HV traveling, in addition to the engine 1, the second rotary machine MG2 may be used as a power source. That is, the HV traveling is a traveling mode that realizes engine driving that travels using the engine 1 as a power source.

  EV traveling is a traveling mode in which traveling is performed using at least one of the first rotating machine MG1 and the second rotating machine MG2 as a power source. In EV traveling, it is possible to travel with the engine 1 stopped. That is, the EV traveling is a traveling mode in which the engine 1 is stopped and the rotating machine driving that travels using at least one of the first rotating machine MG1 and the second rotating machine MG2 as a power source is realized. The hybrid vehicle drive device 1-1 according to the present embodiment includes, as an EV travel mode, a single motor EV mode (single drive EV mode) that causes the vehicle 100 to travel using the second rotary machine MG2 as a single power source, and a first Both motor EV modes (both drive EV modes) for running the vehicle 100 using the rotating machine MG1 and the second rotating machine MG2 as power sources are provided.

  In the engagement table of FIG. 3, the circles in the clutch CL1 column and the brake BK1 column indicate engagement, and the blank column indicates disengagement. The triangle mark indicates that either the clutch CL1 or the brake BK1 is engaged and the other is released. The single motor EV mode is executed, for example, by releasing both the clutch CL1 and the brake BK1. FIG. 4 is a collinear diagram related to the single motor EV mode. In the alignment chart, reference numerals S1, C1, and R1 indicate the first sun gear 11, the first carrier 14, and the first ring gear 13, respectively. Reference numerals S2, C2, and R2 indicate the second sun gear 21 and the second carrier 24, respectively. The 2nd ring gear 23 is shown.

  In the single motor EV mode, the clutch CL1 and the brake BK1 are released. When the brake BK1 is opened, the first sun gear 11 is allowed to rotate, and when the clutch CL1 is opened, the first planetary gear mechanism 10 can be differentially operated. The HV_ECU 50 causes the second rotary machine MG2 to output a positive torque via the MG_ECU 60 to cause the vehicle 100 to generate a driving force in the forward direction. The second ring gear 23 rotates forward in conjunction with the rotation of the drive wheel 32. Here, the normal rotation is the rotation direction of the second ring gear 23 when the vehicle 100 moves forward. The HV_ECU 50 operates the first rotary machine MG1 as a generator to reduce drag loss. Specifically, the HV_ECU 50 generates a power by applying a slight torque to the first rotating machine MG1, and sets the rotation speed of the first rotating machine MG1 to zero. Thereby, the drag loss of the first rotary machine MG1 can be reduced. Further, even when the MG1 torque is set to 0, the MG1 torque may not be applied if the MG1 rotation speed can be maintained at 0 using the cogging torque. Alternatively, the MG1 rotation speed may be set to 0 by the d-axis lock of the first rotating machine MG1.

  The first ring gear 13 rotates along with the second carrier 24 and rotates forward. In the first planetary gear mechanism 10, since the clutch CL1 and the brake BK1 are in the neutral state, the engine 1 is not rotated and the first carrier 14 stops rotating. Therefore, it is possible to increase the amount of regeneration. The first sun gear 11 idles and rotates negatively. The neutral state of the first planetary gear mechanism 10 is a state in which no power is transmitted between the first ring gear 13 and the first carrier 14, that is, the engine 1 and the second planetary gear mechanism 20 are disconnected. In this state, power transmission is interrupted. The first planetary gear mechanism 10 is connected to connect the engine 1 and the second planetary gear mechanism 20 when at least one of the transmission clutch CL1 and the transmission brake BK1 is engaged.

  When traveling in the single motor EV mode, the battery may be fully charged and regenerative energy may not be obtained. In this case, it is conceivable to use an engine brake together. By engaging the clutch CL <b> 1 or the brake BK <b> 1, the engine 1 can be connected to the drive wheel 32 and the engine brake can be applied to the drive wheel 32. As shown by a triangle mark in FIG. 3, when the clutch CL1 or the brake BK1 is engaged in the single motor EV mode, the engine 1 is brought into a rotating state, and the engine speed is increased by the first rotating machine MG1 to be in an engine braking state. be able to.

  In the dual motor EV mode (double drive EV mode), the HV_ECU 50 engages the clutch CL1 and the brake BK1. FIG. 5 is a collinear diagram related to the both-motor EV mode. When the clutch CL1 is engaged, the differential of the first planetary gear mechanism 10 is restricted, and when the brake BK1 is engaged, the rotation of the first sun gear 11 is restricted. Accordingly, the rotation of all the rotating elements of the first planetary gear mechanism 10 is stopped. By restricting the rotation of the first ring gear 13 that is the output element, the second carrier 24 connected thereto is locked to zero rotation.

  The HV_ECU 50 causes the first rotary machine MG1 and the second rotary machine MG2 to output driving driving torque, respectively. Since the rotation of the second carrier 24 is restricted, the second carrier 24 can take a reaction force against the torque of the first rotating machine MG <b> 1 and output the torque of the first rotating machine MG <b> 1 from the second ring gear 23. The first rotating machine MG1 can output a positive torque from the second ring gear 23 by outputting a negative torque and rotating negatively when moving forward. On the other hand, at the time of reverse travel, the first rotary machine MG1 can output negative torque from the second ring gear 23 by outputting positive torque and rotating forward.

  In HV traveling, the second planetary gear mechanism 20 as the differential unit 41 is based on a differential state, and the first planetary gear mechanism 10 of the transmission unit 40 is switched between low and high. In HV traveling, vehicle 100 travels with direct torque and MG2 torque while taking reaction force with first rotating machine MG1.

  In the HV low mode, the HV_ECU 50 engages the clutch CL1 and releases the brake BK1. FIG. 6 is a collinear diagram related to the HV low mode. When the clutch CL1 is engaged, the differential of the first planetary gear mechanism 10 is restricted, and the rotating elements 11, 13, and 14 rotate integrally. Accordingly, the rotation of the engine 1 is not accelerated or decelerated and is transmitted from the first ring gear 13 to the second carrier 24 at a constant speed. The gear ratio of the first planetary gear mechanism 10 during this direct connection is 1.

  On the other hand, in the HV high mode, the HV_ECU 50 releases the clutch CL1 and engages the brake BK1. FIG. 7 is a collinear diagram related to the HV high mode. The engagement of the brake BK1 restricts the rotation of the first sun gear 11. Therefore, the first planetary gear mechanism 10 enters an overdrive (OD) state in which the rotation of the engine 1 input to the first carrier 14 is increased and output from the first ring gear 13. As described above, the first planetary gear mechanism 10 can increase the rotation speed of the engine 1 and output it. The gear ratio of the first planetary gear mechanism 10 during overdrive can be set to 0.7, for example.

  As described above, the switching device including the clutch CL1 and the brake BK1 switches between a state in which the differential of the first planetary gear mechanism 10 is regulated and a state in which the differential of the first planetary gear mechanism 10 is allowed to switch. The gear mechanism 10 is shifted. The hybrid vehicle drive device 1-1 can switch between the HV high mode and the HV low mode by the transmission unit 40 including the first planetary gear mechanism 10, the clutch CL1, and the brake BK1, and improves the transmission efficiency of the vehicle 100. Can be made. Further, the second planetary gear mechanism 20 as the differential unit 41 is connected in series with the rear stage of the transmission unit 40. Since the first planetary gear mechanism 10 is overdriven, there is an advantage that the first rotating machine MG1 does not have to be greatly increased in torque.

  For example, the HV_ECU 50 selects the HV high mode at high vehicle speeds and the HV low mode at medium to low vehicle speeds. FIG. 8 is a diagram showing a map relating to mode selection according to the present embodiment. In FIG. 8, the horizontal axis represents the vehicle speed, and the vertical axis represents the required driving force. The HV_ECU 50 can switch between HV traveling that is engine-driven and EV traveling that is driven by a rotating machine in accordance with an operation region determined based on the vehicle speed and the required driving force.

  As shown in FIG. 8, the low load region where the vehicle speed is low and the required driving force is small is the motor travel region. In the motor travel area, EV travel is selected. In the motor travel range, for example, the single motor EV mode is selected when the load is low (single drive region), and the double drive EV mode is selected when the load is high (both drive regions). The HV_ECU 50 basically gives priority to the MG drive over the engine drive when the state of charge SOC is present, that is, in a state where the MG drive is possible. The motor travel area including the single drive area and the both drive areas corresponds to an operation area in which the rotating machine is driven. When the operating point determined based on the vehicle speed and the required driving force is within the motor travel range, the HV_ECU 50 basically selects EV travel (single motor EV mode or dual drive EV mode).

  The region of higher vehicle speed and higher load than the motor travel region is the engine travel region. The engine travel area is further divided into a direct connection (low) area and an OD (high) area. The direct connection region is an engine traveling region where the HV low mode is selected. The OD region is an engine traveling region where the HV high mode is selected. The OD region is a high vehicle speed region, and the direct connection region is a medium to low vehicle speed region. The direct connection area is set on the higher load side than the OD area. By making the transmission 40 overdrive at high vehicle speeds and low loads, fuel consumption can be improved. The engine travel area configured to include the direct connection area and the OD area corresponds to an operation area in which the engine is driven. The HV_ECU 50 basically selects HV traveling (HV low mode or HV high mode) when the operating point determined based on the vehicle speed and the required driving force is within the engine traveling range.

  In the present embodiment, by shifting the speed of the engine 1 by switching between the HV high mode and the HV low mode and outputting it, the number of mechanical points becomes two, and the fuel efficiency can be improved. The mechanical point is a highly efficient operating point in which all the power input to the planetary gear mechanisms 10 and 20 is transmitted to the counter drive gear 25 by mechanical transmission without passing through an electrical path.

  In the hybrid vehicle drive device 1-1 according to the present embodiment, the first planetary gear mechanism 10 can increase the rotation of the engine 1 and output it from the first ring gear 13. Therefore, the hybrid vehicle drive device 1-1 is further provided on the high gear side with respect to the mechanical point when the engine 1 is directly connected to the second carrier 24 without the first planetary gear mechanism 10. Has one mechanical point. That is, the hybrid vehicle drive device 1-1 has two mechanical points on the high gear side. Therefore, the hybrid vehicle drive device 1-1 can realize a hybrid system that can improve fuel efficiency by improving transmission efficiency during high-speed traveling.

  Further, the hybrid vehicle drive device 1-1 can regulate the rotation of the input element of the second planetary gear mechanism 20 by engaging the clutch CL1 and the brake BK1 of the transmission unit 40, and the dual motor EV mode. It is possible to run by. For this reason, it is not necessary to provide a separate clutch or the like in order to realize the both-motor EV mode, and the configuration is simplified. In the layout of the present embodiment, the reduction ratio of the second rotary machine MG2 can be increased. Further, a compact arrangement can be realized by the FF or RR layout.

(Reverse drive)
In the case of reverse travel, during engine travel, the first rotary machine MG1 generates power as a generator, the second rotary machine MG2 powers as a motor, travels negatively, outputs negative torque, and travels. When the state of charge of the battery is sufficient, the second rotary machine MG2 may independently rotate in the single drive EV mode to run on the motor. It is also possible to drive backward with the second carrier 24 fixed and in the double drive EV mode.

(Cooperative shift control)
When switching between the HV high mode and the HV low mode, the HV_ECU 50 can execute coordinated shift control that simultaneously shifts the first planetary gear mechanism 10 and the second planetary gear mechanism 20. In the coordinated shift control, the HV_ECU 50 increases one gear ratio of the first planetary gear mechanism 10 and the second planetary gear mechanism 20 and decreases the other gear ratio.

  When switching from the HV high mode to the HV low mode, the HV_ECU 50 changes the gear ratio of the second planetary gear mechanism 20 to the high gear side in synchronization with the mode switching. Thereby, the discontinuous change of the gear ratio in the whole from the engine 1 of the vehicle 100 to the drive wheel 32 can be suppressed or reduced, and the degree of the change of the gear ratio can be reduced. By suppressing the change in the gear ratio from the engine 1 to the drive wheels 32, it is possible to reduce the amount of adjustment of the engine speed that accompanies the speed change, or to eliminate the need to adjust the engine speed. For example, the HV_ECU 50 shifts the first planetary gear mechanism 10 and the second planetary gear mechanism 20 in a coordinated manner so as to continuously change the gear ratio of the entire vehicle 100 to the low side.

  On the other hand, when switching from the HV low mode to the HV high mode, the HV_ECU 50 changes the gear ratio of the second planetary gear mechanism 20 to the low gear side in synchronization with the mode switching. Thereby, the discontinuous change of the gear ratio in the entire vehicle 100 can be suppressed or reduced, and the degree of change of the gear ratio can be reduced. For example, the HV_ECU 50 shifts the first planetary gear mechanism 10 and the second planetary gear mechanism 20 in a coordinated manner so as to continuously change the gear ratio of the entire vehicle 100 to the high side.

  The adjustment of the gear ratio of the second planetary gear mechanism 20 is performed, for example, by controlling the rotational speed of the first rotating machine MG1. For example, the HV_ECU 50 controls the first rotary machine MG1 so as to change the speed ratio between the input shaft 2 and the counter drive gear 25 steplessly. As a result, the entire transmission including the planetary gear mechanisms 10, 20, the first rotating machine MG1, the clutch CL1, and the brake BK1, that is, the transmission including the differential unit 41 and the transmission unit 40 operates as an electric continuously variable transmission. Regeneration is performed mainly by the second rotating machine MG2. Since the transmission ratio width of the transmission including the differential unit 41 and the transmission unit 40 is wide, the transmission ratio from the differential unit 41 to the drive wheels 32 can be relatively large. Further, power circulation during high vehicle speed traveling in the HV traveling mode is reduced.

(Engine start control)
For example, the HV_ECU 50 starts the stopped engine 1 when shifting from the EV travel mode to the HV travel mode. For example, when starting the engine 1, the HV_ECU 50 engages the clutch CL1 or the brake BK1 from the single motor EV mode using the second rotating machine MG2, and increases the engine speed by the first rotating machine MG1 to ignite. Then, the engine 1 is started. At this time, the second rotary machine MG2 additionally outputs reaction force canceling torque. In this case, when the hybrid vehicle drive device 1-1 attempts to motor the first rotating machine MG1 after the clutch CL1 or the brake BK1 is completely engaged, the first rotating machine MG1 may be over-rotated. Therefore, half-engagement control of the clutch CL1 or the brake BK1 is performed when starting the engine.

  By the way, in the hybrid vehicle drive device 1-1 of the present embodiment, in the switching setting such as the region X in the mode selection map illustrated in FIG. There is a possibility that the HV traveling and the EV traveling are frequently switched with respect to the change in the degree (required driving force). For example, in FIG. 8, the arrow a tends to increase the switching frequency with respect to the arrow b, and there is a possibility that switching between the HV traveling and the EV traveling that is more busy occurs.

  Therefore, the hybrid vehicle drive device 1-1 of the present embodiment increases the switching hysteresis as the required driving force in the motor travel area as the operation area for driving the rotating machine illustrated in FIG. 8 is narrower. Thereby, the hybrid vehicle drive device 1-1 suppresses frequent switching between the rotating machine driving and the engine driving, and suppresses hunting due to switching between the engine driving and the rotating machine driving.

  Specifically, the HV_ECU 50 switches the hysteresis between the HV traveling as the engine drive and the EV traveling as the rotating machine drive in accordance with the size of the required driving force that sets the motor traveling region that is the operation region to be driven by the rotating machine. To change. The HV_ECU 50 avoids frequent switching by increasing the switching hysteresis between the HV traveling and the EV traveling at the vehicle speed as the width of the required driving force with respect to the vehicle speed in the motor traveling region is narrower.

  Here, the switching hysteresis is a parameter for setting a width between a boundary (threshold) for switching from HV traveling to EV traveling and a boundary (threshold) for switching from EV traveling to HV traveling. As the switching hysteresis increases, the switching frequency between HV traveling and EV traveling tends to be reduced. On the other hand, as the switching hysteresis decreases, the switching frequency between HV traveling and EV traveling tends to increase. The HV_ECU 50 of the present embodiment reduces the switching frequency between the HV traveling and the EV traveling in the vehicle speed range by increasing the switching hysteresis at the vehicle speed as the width of the required driving force with respect to the vehicle speed in the motor traveling region is narrower. be able to.

  For example, as a more preferable example, the switching hysteresis is set according to the width of the required driving force that defines the motor travel range. Further, as a more preferable example, the switching hysteresis may be set according to the elapsed time after switching between HV traveling and EV traveling. Here, as a more preferable example, like the motor travel area illustrated in FIG. 8, the change in the required driving force range that defines the motor travel area has a step with respect to the vehicle speed direction. In this case, as a more preferable example, the step is an operation region in the dual drive EV mode that is driven by the first rotary machine MG1 and the second rotary machine MG2 in the motor travel range illustrated in FIG. It is formed based on the region X according to the difference between the drive region and the single drive region that is the operation region of the single motor EV mode driven by the second rotary machine MG2 alone. In the motor travel area illustrated in FIG. 8, the single drive area on the low load side is a wider area on the high vehicle speed side than both drive areas on the high load side. As a result, the region X is formed in the engine driving region on the high load side of the single driving region and on the high vehicle speed side of both driving regions. As a result, in the motor traveling area illustrated in FIG. 8, the required driving force area in the vehicle speed area corresponding to the area X is narrower than the required driving force area in the vehicle speed area on the lower speed side than the area X. Yes.

  Further, as a more preferable example, when the HV_ECU 50 detects the driver's intention of fuel efficiency priority driving (for example, when the driver detects the ON operation of the fuel efficiency priority switch), the driver's intention of fuel efficiency priority driving is detected. The switching hysteresis may be made relatively small as compared with the case where no is detected. Thereby, although the drive apparatus 1-1 for hybrid vehicles can change to EV driving | running | working and HV driving | running | working frequently, it can transfer to EV driving | running | working actively and can suppress fuel consumption.

  Further, as a more preferable example, the HV_ECU 50 sets a relative switching hysteresis when the responsiveness of the engaging device such as the clutch CL1 and the brake BK1 is poor as compared with the case where the responsiveness of the engaging device is good. It may be made larger. For example, when the engine is started from the single motor EV mode shown in FIG. 4 in the vehicle speed range corresponding to the region X illustrated in FIG. The half-engagement control of the brake BK1 is performed. At this time, when the controllability and responsiveness of the engagement device are deteriorated due to factors such as the relatively low temperature (ATF temperature) of the hydraulic oil that operates the clutch CL1 and the brake BK1, the engine start shock is noticeable. There is. For this reason, when the responsiveness of the engagement device is poor, the hybrid vehicle drive device 1-1 reduces the frequency of switching to EV travel by relatively increasing the switching hysteresis, and the engine start frequency Reduce. Thereby, the hybrid vehicle drive device 1-1 can suppress the engine start shock.

  Next, with reference to FIG. 9 and FIG. 10, an example of control in the hybrid vehicle drive device 1-1 of the present embodiment will be described. The control flow shown in FIG. 9 is repeatedly executed at predetermined intervals, for example.

  First, the HV_ECU 50 determines whether or not HV traveling is being performed in the region X illustrated in FIG. 8 (step ST1). For example, the HV_ECU 50 determines whether or not the vehicle is traveling in the HV in the region X by determining whether or not the operating point determined according to the required driving force based on the accelerator opening and the vehicle speed is located in the region X. Determine.

  When the HV_ECU 50 determines that the vehicle is traveling in the HV in the region X (step ST1: Yes), the HV_ECU 50 counts the elapsed time T of the HV travel after switching between the EV travel and the HV travel, and the elapsed time T is set in advance. It is determined whether or not it is longer than the predetermined value T1 (step ST2).

  When the HV_ECU 50 determines that the elapsed time T is longer than the predetermined value T (step ST2: Yes), the HV_ECU 50 sets the required driving force hysteresis TLL (step ST3), and ends this control flow. This required driving force hysteresis TLL corresponds to the switching hysteresis described above. For example, in the vehicle speed range corresponding to the region X in FIG. 8, the HV_ECU 50 requires a required driving force to switch from EV travel to HV travel when the accelerator is stepped on (for example, a solid line at the boundary between the motor travel region and the engine travel region). ) Is the required driving force obtained by subtracting the required driving force hiss TLL from the HV traveling to the EV traveling (for example, refer to the dotted line L1 in FIG. 8). Thereby, when the operating point is in the region X, the hybrid vehicle drive device 1-1 can make it difficult to return to EV traveling.

  For example, the HV_ECU 50 may calculate the required driving force hysteresis TLL according to the elapsed time T based on a map related to the required driving force hysteresis TLL as shown in FIG. Here, the required driving force hysteresis TLL is set so as to decrease as the elapsed time T increases and to be constant in a region longer than the predetermined elapsed time T. As a result, the hybrid vehicle drive device 1-1 can easily switch to EV traveling after a certain amount of time has elapsed from EV traveling to HV traveling, so both busy switching suppression and fuel efficiency can be achieved. can do.

  If the HV_ECU 50 determines in step ST2 that the elapsed time T is equal to or less than the predetermined value T (step ST2: No), the HV_ECU 50 prohibits EV traveling by returning the accelerator (step ST4), and ends this control flow. Thereby, even if the accelerator opening returns to the fully closed state, for example, the hybrid vehicle drive device 1-1 can prohibit switching to the EV traveling for a certain period of time.

  If the HV_ECU 50 determines in step ST1 that the vehicle is not traveling in the region X (step ST1: No), the HV_ECU 50 sets the required driving force hysteresis TLS for the normal region smaller than the required driving force hysteresis TLL (step ST5). End the control flow. This required driving force hysteresis TLS corresponds to the switching hysteresis described above. As a result, the hybrid vehicle drive device 1-1 can reduce the switching hysteresis as the width of the required driving force in the motor travel region illustrated in FIG. 8 increases. In other words, the required driving force in the motor travel region can be reduced. As the width is narrower, the switching hysteresis can be increased.

  Next, with reference to FIG. 11, an example of the operation | movement in the hybrid vehicle drive device 1-1 of this embodiment is demonstrated. FIG. 11 is a time chart showing a state in which the operating point is in the region X shown in FIG. 11, (a) is the engine speed, (b) is the MG1 torque, (c) is the MG1 speed, (d) is the MG2 torque, (e) is the MG2 speed, and (f) is the supply to the brake BK1. The hydraulic pressure (PbBK1), (g) indicates the hydraulic pressure supplied to the clutch CL1 (PbCL1), (h) indicates the accelerator opening, and (i) indicates the vehicle speed.

  In the example shown in FIG. 11, the hybrid vehicle drive device 1-1 counts an elapsed time T from the start of HV traveling in the region X in a state where the operating point is in the region X and HV traveling is in progress. It is determined whether it is longer than a predetermined value T1 set in advance. Then, in the hybrid vehicle drive device 1-1, the accelerator is returned at time t1, and the accelerator opening decreases toward θ1. The hybrid vehicle drive device 1-1 sets the required driving force hysteresis TLL from the elapsed time T at time t2, and determines whether to switch to EV traveling based on the current operating point (history requirement clear determination). Then, when the hybrid vehicle drive device 1-1 determines to switch to the EV travel at time t3, the MG1 torque is set to 0, the MG1 rotational speed is decreased, the MG2 torque is increased, and the second rotating machine is started from time t4. Switch to EV traveling by MG2 (MG2 drive switching).

  According to the hybrid vehicle drive device 1-1 described above, the switching hysteresis is increased as the required driving force in the operation region (motor traveling region) for rotating machine driving (EV traveling) is narrower. It is possible to suppress frequent switching between driving and engine driving (HV traveling), and it is possible to suppress hunting due to switching between rotating machine driving and engine driving.

[Embodiment 2]
FIG. 12 is a skeleton diagram of the vehicle according to the second embodiment. FIG. 13 is an alignment chart according to the HV traveling mode. FIG. 14 is a collinear diagram related to the EV travel mode. The hybrid vehicle drive device according to the second embodiment is different from the hybrid vehicle drive device according to the first embodiment in that it does not include the above-described transmission unit. In addition, about the structure, operation | movement, and effect which are common in embodiment mentioned above, the overlapping description is abbreviate | omitted as much as possible.

  The hybrid vehicle drive device 1-2 of this embodiment shown in FIG. 12 does not include the transmission unit 40 including the first planetary gear mechanism 10, the clutch CL1, and the brake BK1 described in FIG. Instead, a brake Bcr is provided. Here, the rotating shaft 33 of the first rotating machine MG1 is hollow, and the input shaft 2 connected to the output shaft of the engine 1 is inserted therein. The input shaft 2 is provided with an oil pump OP at the end opposite to the engine 1. A rotation shaft 33 of the first rotating machine MG1 is connected to the second sun gear 21 of the second planetary gear mechanism 20. A counter drive gear 25 is connected to the second ring gear 23. The input shaft 2 is connected to the second carrier 24 of the present embodiment and rotates integrally with the input shaft 2.

  The brake Bcr is an engagement device for fixing the output shaft (crankshaft) of the engine 1 and is a brake device that can regulate the rotation of the input shaft 2. The brake Bcr has an engagement element connected to the input shaft 2 and an engagement element connected to the vehicle body side, for example, a case of the power transmission device. The brake Bcr can be a friction engagement type clutch device similar to the clutch CL1 or the like. However, the brake Bcr is not limited to this, and a known clutch device such as a meshing type dog clutch is used to reduce drag during HV traveling. It may be used as a brake Bcr. The brake Bcr is engaged or released by being controlled by, for example, hydraulic pressure. The completely engaged brake Bcr connects the input shaft 2 and the vehicle body side and can regulate the rotation of the input shaft 2. On the other hand, the opened brake Bcr separates the input shaft 2 from the vehicle body side and allows the input shaft 2 to rotate. The brake Bcr can be controlled to be in a half-engaged state. The brake Bcr in the half-engaged state allows the input shaft 2 to rotate. In this case, the HV_ECU 50 outputs a command value for the supply hydraulic pressure (Pbcr) for the brake Bcr in place of the command value for the supply hydraulic pressure (PbCL1) and the command value for the supply hydraulic pressure (PbBK1) as shown by the dotted line in FIG. .

  The vehicle 100 can selectively execute HV traveling or EV traveling. The collinear diagram of FIG. 13 represents an HV traveling mode that realizes engine driving that travels using the engine 1 as a power source, and the collinear diagram of FIG. 14 stops the engine 1 and the first rotating machine MG1 or the second rotating machine. An EV traveling mode that realizes a rotating machine drive that travels using at least one of MG2 as a power source is shown.

  In the HV traveling mode of FIG. 13, the hybrid vehicle drive device 1-2 releases the brake Bcr, the engine 1 is operated, and the direct torque and MG2 torque from the engine 1 while taking the reaction force with the first rotating machine MG1. And drive on. On the other hand, in the EV travel mode of FIG. 14, the hybrid vehicle drive device 1-2 is engaged with the brake Bcr, and the output shaft of the engine 1 is fixed by the brake Bcr. The machine MG2 is operated and travels with that torque.

  For example, when the operating point determined based on the vehicle speed and the required driving force is within the motor travel area illustrated in FIG. 8, the HV_ECU 50 basically selects EV travel (EV travel mode). For example, when the operating point determined based on the vehicle speed and the required driving force is within the engine travel range illustrated in FIG. 8, the HV_ECU 50 basically selects HV travel (HV travel mode). In the present embodiment, the motor travel area is a single area with no distinction between the single drive area and both drive areas, and the engine travel area is a single area without distinction between the direct connection area and the OD area. It is an area.

  The hybrid vehicle drive device 1-2 configured as described above also increases the switching hysteresis as the width of the required driving force in the operation region (motor traveling region) for rotating machine driving (EV traveling) decreases. It is possible to suppress frequent switching between rotating machine driving and engine driving (HV traveling), and it is possible to suppress hunting due to switching between rotating machine driving and engine driving.

  The hybrid vehicle drive device according to the above-described embodiment of the present invention is not limited to the above-described embodiment, and various modifications can be made within the scope described in the claims. The hybrid vehicle drive device according to the present embodiment may be configured by appropriately combining the components of the embodiments described above.

1-1, 1-2 Hybrid vehicle drive device 1 Engine (engine)
MG1 First rotating machine MG2 Second rotating machine

Claims (1)

With the agency,
With a rotating machine,
It is possible to switch between an engine drive that travels using the engine as a power source and a rotary machine drive that stops the engine and travels using the rotating machine as a power source according to an operation region determined based on a vehicle speed and a required driving force, As the width of the required driving force with respect to the vehicle speed in the operation region to be driven by the rotating machine is narrower, the switching hysteresis between the engine driving and the rotating machine driving at the vehicle speed is increased.
Drive device for hybrid vehicle.

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