JP6690520B2 - Control device for hybrid vehicle - Google Patents

Description

  The present invention relates to a control device for a multi-axle hybrid vehicle in which an engine and a first rotating machine are coaxially arranged and a second rotating machine is arranged on different axes.

  A multi-axis electric continuously variable transmission having a first planetary mechanism and a first rotating machine arranged on a first shaft, and a second rotating machine arranged on a second shaft different from the first shaft. Machine (THS), a second planetary mechanism, a first brake and a first clutch for shifting, and a stepped transmission provided between the engine and the first planetary mechanism; A hybrid vehicle is disclosed that includes a stepped transmission and a second clutch provided between the stepped transmission. For example, the vehicle described in Patent Document 1 is that. In this patent document 1, by releasing the second clutch, the engine and the first planetary mechanism and the first rotating machine are separated from each other, and the rotation of the engine is stopped. There is no need to drive the engine. As a result, a technique is disclosed in which the loss caused by the rotation of the engine is reduced and the power consumption is improved.

International Publication No. 2013/114594

  In the vehicle as described above, to stop the engine and start the stopped engine while the vehicle is running on the electric motor based on one or both of the first rotating machine and the second rotating machine It is necessary to complete the synchronization of the differential rotation of the second clutch and start the engine after engaging the second clutch. As a result, for example, when a driver's acceleration request is generated, if the engine is started after synchronization and engagement of the differential rotation of the second clutch, drivability of the driver may be deteriorated. It may have worsened.

  The present invention has been made in view of the above circumstances, and an object of the present invention is based on the rotation of either one or both of the first rotating machine and the second rotating machine. (EN) Provided is a vehicle control device capable of suppressing a driver from feeling a deterioration in drivability such as a decrease in responsiveness to a driver's acceleration request when starting an engine that is stopped while a motor is running. Especially.

  The gist of the first invention is that (a) a first planetary mechanism and a first rotating machine arranged on a first shaft, and a second planetary mechanism arranged on a second shaft different from the first shaft. A multi-axis electric continuously variable transmission having a rotating machine, a second planetary mechanism, a first brake and a first clutch for shifting, and are provided between the engine and the first planetary mechanism. A stepped transmission, and a second clutch provided between the electric continuously variable transmission and the stepped transmission, and injecting fuel into a cylinder for ignition when the engine is stopped. A control device for a hybrid vehicle capable of starting ignition by means of: (b) without driving the engine, to either or both of the first rotating machine and the second rotating machine. When the ignition start of the engine is impossible while the electric motor is running , It said than the ignition start is possible, characterized in that to reduce the differential rotation of the second clutch.

  According to this configuration, the multi-axis type having the first planetary gear mechanism and the first rotating machine arranged on the first shaft and the second rotating machine arranged on the second shaft different from the first shaft. An electric continuously variable transmission, a second planetary mechanism, a first brake and a first clutch for shifting, and a stepped transmission provided between the engine and the first planetary mechanism; An ignition starter that includes a second clutch provided between the electric continuously variable transmission and the stepped transmission, and starts the engine by injecting fuel into a cylinder to ignite fuel when the engine is stopped In a control device for a hybrid vehicle capable of performing the above, when ignition start is impossible until a predetermined engine speed is reached, the differential rotation speed of the second clutch is set to be smaller than that when immediate ignition start is possible. Will cause the driver to request acceleration. The time until the oncoming of time or the second clutch to the synchronization of the second clutch that can be shortened when. As a result, it is possible to prevent the driver from feeling a deterioration in drivability due to a delay in starting the engine from the driver's acceleration request, that is, a decrease in responsiveness. Further, when ignition start is possible, the differential rotation of the second clutch is set to be large, so that the loss caused by the rotation of the engine is reduced and the power consumption is improved. In this case, even if a driver's acceleration request is generated, after the second clutch is synchronized, the ignition start can be immediately performed without waiting for the engine to reach a predetermined rotation speed, so that the driver is responsive. It is also suppressed that the driver feels the drivability worse.

FIG. 2 is a diagram illustrating a schematic configuration of each unit related to traveling of a vehicle to which the present invention is applied, and a diagram illustrating a main part of a control system for controlling each unit. 2 is a chart showing each operating state of each engagement device in each traveling mode of the vehicle of FIG. 1. FIG. 2 is a collinear diagram of the vehicle of FIG. 1 in a single drive EV mode. FIG. 2 is a collinear diagram of the vehicle of FIG. 1 in a dual drive EV mode. FIG. 2 is a collinear diagram in forward traveling when the vehicle of FIG. 1 is in an O / DHV mode of an HV traveling mode. FIG. 2 is a collinear diagram of the vehicle of FIG. 1 in a U / DHV mode of an HV traveling mode. FIG. 2 is a collinear diagram in reverse traveling in the OV / DHV mode of the HV traveling mode of the vehicle of FIG. 1, showing the case of engine reverse rotation input. FIG. 2 is a collinear diagram in reverse running of the vehicle of FIG. 1 in the OV / DHV mode of the HV running mode, in the case of normal engine input. FIG. 2 is a collinear diagram of the vehicle of FIG. 1 in a fixed stage mode of the HV traveling mode, which is a case of direct connection. FIG. 2 is a collinear diagram in the fixed stage mode of the HV traveling mode of the vehicle of FIG. 1, showing a case where the output shaft is fixed. FIG. 2 is a diagram showing an example of a torque ratio of MG1 torque to engine torque and a torque ratio of MG2 torque to engine torque in the vehicle of FIG. 1. In the vehicle of FIG. 1, it is a figure which shows an example of the rotation speed ratio of MG1 rotation speed with respect to an engine rotation speed, and the rotation speed ratio of MG2 rotation speed with respect to an engine rotation speed. FIG. 2 is a diagram showing an example of an output ratio of MG1 power to engine power and an output ratio of MG2 power to engine power in the vehicle of FIG. 1. FIG. 2 is a diagram showing an example of a travel mode switching map used for control of switching between engine traveling and motor traveling in the vehicle of FIG. 1, which is a case where traveling is performed with a charge capacity maintained. FIG. 3 is a diagram showing an example of a map for setting a differential rotation speed of a second clutch based on a request for responsiveness in the vehicle of FIG. 1. 3 is a flowchart illustrating an example of a control operation for setting a differential rotation speed of a second clutch based on a request for responsiveness in the vehicle of FIG. 1. 3 is a time chart showing an example of a control operation for synchronizing and engaging the rotational speed of the second clutch in the vehicle of FIG. 1 before starting the engine. 3 is a time chart showing an example of a control operation for engaging the second clutch before starting the engine start in the vehicle of FIG. 1.

  Preferably, the hybrid vehicle includes a power storage device, and the larger the power limit of the power storage device, the smaller the differential rotation of the second clutch. With this configuration, even when the time taken to synchronize the second clutch becomes long due to the large power limitation, it is possible to shorten the synchronization time because the differential rotation of the second clutch is reduced in advance. The time from the engine start request to the engine start is shortened, and it is possible to prevent the driver from feeling a deterioration in drivability due to a decrease in responsiveness.

  Further, preferably, in the hybrid vehicle, the higher the responsiveness request of the driver to the vehicle, the smaller the differential rotation of the second clutch. With this configuration, since the differential rotation of the second clutch is reduced in advance, it is possible to shorten the synchronization time. As a result, the time from the start request of the engine to the start is shortened, and it is possible to meet the high demand for the drivability of the driver by improving the responsiveness.

  Further, preferably, in the hybrid vehicle, when the driver's demand for responsiveness to the vehicle is strong, the differential rotation of the second clutch is set to zero and the engagement of the second clutch is completed. Especially. With this configuration, the differential rotation of the second clutch is set to zero in advance, and the engagement of the second clutch is completed, so that the time from the engine start request to the engine start is shortened. . As a result, the time from the start request of the engine to the start can be shortened, and the responsiveness can be improved to meet the driver's high demand for drivability.

  Further, preferably, when the ignition start of the engine is possible, the rotation speed of the second rotating machine is increased as compared with the case where the ignition start cannot be performed. With this configuration, when the ignition of the engine can be started, the acceleration of the vehicle at the time of starting the engine can be set large, and the responsiveness of the vehicle can be improved. Further, even when the differential rotation speed of the second clutch is set large in order to improve fuel efficiency, the driver is not responsive to drivability due to a decrease in responsiveness by setting a large acceleration of the vehicle at the time of starting the engine. It is possible to suppress the feeling of deterioration.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a diagram illustrating a schematic configuration of each unit related to traveling of a vehicle 10 to which the present invention is applied, and a diagram illustrating a main part of a control system for controlling each unit. In FIG. 1, a vehicle 10 includes an engine (ENG) 12, a first rotating machine MG1, a second rotating machine MG2, and a first rotating machine MG1 and a second rotating machine MG2, which can be a driving force source for traveling. The hybrid vehicle includes a power transmission device 14 and drive wheels 16.

  The engine 12 is a known internal combustion engine, such as a gasoline engine or a diesel engine, which burns a predetermined fuel to output power. Further, the engine 12 starts the normal engine 12 in which fuel is injected into the cylinder and ignites after reaching a predetermined engine speed Ne, and at the same time as the engine 12 stops rotating, fuel is injected into the cylinder and ignited. It is a direct injection engine or the like that can start the engine 12 by performing the operation, that is, can start ignition, and the electronic control unit 90 described later controls the operating state such as the throttle opening or the intake air amount, the fuel supply amount, and the ignition timing. By being controlled, the engine torque Te is controlled.

  The first rotating machine MG1 and the second rotating machine MG2 are so-called motor generators having a function as an electric motor (motor) that generates a drive torque and a function as a generator (generator). The first rotary machine MG1 and the second rotary machine MG2 are provided in the vehicle 10 as a power storage device that transmits and receives electric power, respectively, via the power control unit 18 provided in the vehicle 10 having an inverter unit, a smoothing capacitor, and the like. The output torque (power running torque or regenerative torque) of each of the first rotary machine MG1 and the second rotary machine MG2 is connected to the battery unit 20 and the electric power control unit 18 is controlled by the electronic control unit 90 described later. The MG1 torque Tg and the MG2 torque Tm are controlled.

  The power transmission device 14 is provided in a power transmission path between the engine 12 and the drive wheels 16. The power transmission device 14 cannot relatively rotate a driven gear 30 and a driven gear 30 that mesh with a first power transmission portion 24, a second power transmission portion 26, a drive gear 28 of the first power transmission portion 24, and a case 22 attached to a vehicle body. A fixed shaft 32 fixed to the driven shaft 32, a final gear 34 fixed to the driven shaft 32 so as not to rotate relative to the driven shaft 32 (a final gear 34 having a smaller diameter than the driven gear 30), a differential gear 38 meshing with the final gear 34 via a differential ring gear 36, etc. Is equipped with. The power transmission device 14 also includes an axle 40 and the like connected to the differential gear 38.

  The first power transmission unit 24 is arranged coaxially with the input shaft 42 that is an input rotating member of the first power transmission unit 24, and serves as a first differential unit 44, a second differential unit 46, and a second clutch. It is equipped with a clutch CLr. The first differential unit 44 includes a first planetary gear mechanism 48 and a first rotating machine MG1. The second differential portion 46 includes a second planetary mechanism 50, a clutch CL as a first clutch, and a brake Br as a first brake. The second planetary mechanism 50, the brake Br, and the clutch CL correspond to the stepped transmission of the invention, and the first planetary mechanism 48, the first rotary machine MG1, and the input shaft 42 arranged on the input shaft 42 are different from each other. The second rotary machine MG2 arranged on a different rotor shaft 56 corresponds to the multi-axis electric continuously variable transmission (THS) of the present invention.

  The first planetary mechanism 48 includes a first sun gear S1, a first pinion gear P1, a first carrier CA1 that supports the first pinion gear P1 so as to rotate and revolve, and a first ring gear that meshes with the first sun gear S1 via the first pinion gear P1. It is a known single-pinion type planetary mechanism having R1 and functions as a differential mechanism that produces a differential action. Further, the second planetary mechanism 50 meshes with the second sun gear S2 via the second sun gear S2, the second pinion gear P2, the second carrier CA2 that supports the second pinion gear P2 so that it can rotate and revolve, and the second sun gear S2 via the second pinion gear P2. It is a known single-pinion type planetary mechanism having two ring gears R2 and functions as a differential mechanism that produces a differential action.

  The first carrier CA1 is the first rotating element RE1 as an input element connected to the output rotating member of the second differential portion 46 (that is, the second ring gear R2 of the second planetary mechanism 50), and the first differential portion CA1. It functions as an input rotation member of 44. The first sun gear S1 is a second rotating element RE2 as a reaction force element that is integrally connected to the rotor shaft 52 of the first rotating machine MG1 and is connected to the first rotating machine MG1 so as to be capable of transmitting power. The first ring gear R1 is integrally connected to the drive gear 28 (that is, provided so as to rotate integrally with the drive gear 28), and is connected to the drive wheel 16 as a third rotating element RE3 as an output element. And functions as an output rotating member of the first differential section 44.

  The second sun gear S2 is a fourth rotating element RE4 that is integrally connected to the input shaft 42 and is connected to the engine 12 via the input shaft 42 so that power can be transmitted. Functions as a member. The second carrier CA2 is a fifth rotating element RE5 that is selectively connected to the case 22 via the brake Br. The second ring gear R2 is the sixth rotating element RE6 connected to the input rotating member of the first differential unit 44 (that is, the first carrier CA1 of the first planetary mechanism 48) and the output rotation of the second differential unit 46. Functions as a member. Further, the second carrier CA2 and the second ring gear R2 are selectively connected via the clutch CL. Further, the first ring gear R1 and the second carrier CA2 are selectively connected via a clutch CLr. Therefore, the brake Br selectively connects the fifth rotating element RE5 to the case 22 that is a non-rotating member. Further, the clutch CLr selectively connects the third rotating element RE3 and the fifth rotating element RE5. Further, the clutch CL selectively connects the fifth rotating element RE5 and the sixth rotating element RE6.

  Each of the clutch CL, the brake Br, and the clutch CLr is preferably a wet friction engagement device, and is a multi-plate hydraulic friction engagement device engagement-controlled by a hydraulic actuator. The clutch CL, the brake Br, and the clutch CLr are hydraulic pressures respectively supplied from the hydraulic pressure control circuit 54 when the hydraulic pressure control circuit 54 provided in the vehicle 10 is controlled by an electronic control unit 90 described later. The operating state (state such as engagement and release) is controlled according to CL hydraulic pressure PCL, Br hydraulic pressure Pb1, CLr hydraulic pressure PCLr). The vehicle 10 is provided with a mechanical oil pump 55 (also referred to as OP55), and in the power transmission device 14, the OP55 switches the operating states of the clutch CL, the brake Br, and the clutch CR, and lubricates each part. And hydraulic oil used for cooling each part. The OP 55 is connected to any rotating member (a rotating element is also the same) of the power transmission device 14, and is driven according to the rotation of the rotating member. In this embodiment, the OP 55 is connected to the first rotation element RE1 (here, the sixth rotation element RE6 is also synonymous). Further, if it is necessary to supply the hydraulic oil when the rotation of the rotary member to which the OP 55 is connected is stopped, an electric oil pump is provided in addition to the OP 55, for example. Alternatively, instead of OP55, an electric oil pump may be provided.

  The first planetary gear mechanism 48 divides the power of the engine 12 input to the first carrier CA1 into the first rotary machine MG1 and the first ring gear R1 (the distribution is also agreed) in a state in which differential is allowed. It is possible to function as. Therefore, in the vehicle 10, the direct torque mechanically transmitted to the first ring gear R1 (also referred to as the engine direct torque) by taking the reaction force of the engine torque Te input to the first carrier CA1 by the first rotary machine MG1. And the MG2 torque Tm generated by the second rotary machine MG2 driven by the power generated by the first rotary machine MG1 by the power divided by the first rotary machine MG1.

  The second differential portion 46 forms four states of a direct connection state, a reverse rotation speed change state of the engine 12, a neutral state (neutral state), and an internal lock state by switching each operating state of the clutch CL and the brake Br. It is possible to Specifically, when the clutch CL is engaged, the second differential portion 46 is in a direct connection state in which the rotating elements of the second planetary mechanism 50 are integrally rotated. Further, in the second differential portion 46, in the engaged state of the brake Br, the second ring gear R2 (the output rotating member of the second differential portion 46) is negatively rotated with respect to the positive rotation of the engine rotation speed Ne. 12 reverse rotation speed change states are set. Further, the second differential portion 46 is in a neutral state where the differential of the second planetary mechanism 50 is allowed in the released state of the clutch CL and the released state of the brake Br. Further, the second differential portion 46 is in an internal lock state in which rotation of each rotating element of the second planetary mechanism 50 is stopped in the engaged state of the clutch CL and the engaged state of the brake Br.

  The first power transmission unit 24 can constitute an electric continuously variable transmission that operates at a power split ratio different from the power split ratio in the first differential unit 44. That is, in the first power transmission unit 24, the first carrier CA1 (first rotating element RE1) and the second ring gear R2 (sixth rotating element RE6) are connected, and the clutch CLr is set to the engaged state. As a result, the first ring gear R1 (third rotating element RE3) and the second carrier CA2 (fifth rotating element RE5) are connected, so that the first differential portion 44 and the second differential portion 46 have 1 An electric system that constitutes two differential mechanisms and operates the entire first differential portion 44 and the second differential portion 46 at a power split ratio different from the power split ratio of the first differential portion 44 alone. It becomes possible to function as a continuously variable transmission.

  In the first power transmission unit 24, the second differential unit 46 and the first differential unit 44 in which the above-mentioned four states are formed are connected to each other, and the vehicle 10 is configured to switch the operating state of the clutch CLr. Thus, it becomes possible to realize a plurality of traveling modes described later.

  In the first power transmission unit 24 configured as above, the power of the engine 12 and the power of the first rotary machine MG1 are transmitted from the drive gear 28 between the first differential unit 44 and the drive wheels 16. It is transmitted to a driven gear 30 which is interposed in the path and meshes with the drive gear 28. Therefore, the engine 12 and the first rotary machine MG1 are coupled to the drive wheels 16 via the first power transmission unit 24 so that power can be transmitted.

  The second power transmission unit 26 meshes with the rotor shaft 56 of the second rotary machine MG2 and the driven gear 30 that are arranged parallel to the input shaft 42 separately from the second rotary machine MG2 and the input shaft 42, and the rotor shaft thereof. A reduction gear 58 (a reduction gear 58 having a diameter smaller than that of the driven gear 30) connected to 56 is provided. As a result, in the second power transmission unit 26, the power of the second rotary machine MG2 is transmitted to the driven gear 30 without passing through the first power transmission unit 24 (that is, the first differential unit 44 and the second differential unit 46). Transmitted. Therefore, the second rotary machine MG2 is coupled to the drive wheels 16 so as to be able to transmit power without the first power transmission unit 24. That is, the second rotating machine MG2 is a rotating machine that is capable of transmitting power to the axle 40 that is the output rotating member of the power transmission device 14 without the first power transmission unit 24. As the output rotating member of the power transmission device 14, the final gear 34 and the differential ring gear 36 are also synonymous with the axle 40.

  The vehicle 10 includes an electronic control device 90 including a control device that controls each unit related to traveling. The electronic control unit 90 includes, for example, a so-called microcomputer including a CPU, a RAM, a ROM, an input / output interface, and the like, and the CPU uses a temporary storage function of the RAM and follows a program stored in the ROM in advance. Various controls of the vehicle 10 are executed by performing signal processing. For example, the electronic control unit 90 is configured to execute the output control of the engine 12, the first rotary machine MG1, and the second rotary machine MG2, the switching control of the traveling mode described later, and the like, and the engine is executed as necessary. It is configured separately for control, rotary machine control, hydraulic control, etc.

  The electronic control unit 90 includes various sensors provided on the vehicle 10 (for example, an engine rotation speed sensor 70, an output rotation speed sensor 72, an MG1 rotation speed sensor 74 such as a resolver, an MG2 rotation speed sensor 76 such as a resolver, an accelerator opening, etc.). Degree sensor 78, shift position sensor 80, operation mode selection switch 82, engine water temperature sensor 84, engine crank angle sensor 86, battery sensor 87, hydraulic pressure sensor 88, and other various signals based on detection values, for example, engine rotation speed Ne (rpm). , Output rotation speed No (rpm), which is the rotation speed of drive gear 28 corresponding to vehicle speed V (Km / h), MG1 rotation speed Ng (rpm), MG2 rotation speed Nm (rpm), accelerator opening θacc (%) , The operation position Psh of the shift lever, the operation mode signal Mo, the battery unit 20 Battery temperature THbat (° C), battery charge / discharge current Ibat (A), battery voltage Vbat (V), CLr hydraulic pressure PCLr (MPa), engine coolant temperature Tw (° C) which is the coolant temperature of the engine, crank angle θcr (deg) Further, various command signals (for example, engine control command signal Se) are supplied from the electronic control device 90 to each device (for example, the engine 12, the power control unit 18, the hydraulic control circuit 54, etc.) provided in the vehicle 10. , A rotary machine control command signal Sm, a hydraulic control command signal Sp, etc.) are supplied.

  The operation mode selection switch 82 is provided, for example, on a steering wheel (not shown), an instrument panel (not shown), etc., for example, (a) a fuel economy-oriented eco mode, (b) a normal mode corresponding to normal running, And (c) a selection operation member for the driver to select one of the sport modes with an emphasis on drivability, and when the driver presses the operation mode selection switch 82, the eco mode, the normal mode, and the sport Any of the modes can be selected. In the normal mode, for the same accelerator operation amount, that is, the accelerator opening θacc, a larger traveling driving force is generated than in the eco mode, and in the sports mode, the same accelerator operation amount, that is, the accelerator opening θacc is larger than that in the normal mode. The driving force is generated. A selection button is provided for each of the eco mode and the sport mode. When each button is pressed, the eco mode and sport mode are selected, and when neither is pressed, the normal mode is selected. May be

  The electronic control unit 90 calculates the state of charge (charge capacity) SOC (hereinafter referred to as battery capacity SOC) of the battery unit 20 based on, for example, the battery charge / discharge current Ibat and the battery voltage Vbat. Further, the electronic control unit 80 defines a limit on the usable power of the battery unit 20, that is, a limit on the charging power of the battery unit 20, based on the battery temperature THbat and the charge capacity SOC of the battery unit 20, for example. The charge limit power Win (W) and the discharge limit power Wout (W) that define the limit of the output power of the battery unit 20 are calculated. The charge / discharge limited power Win, Wout is increased as the battery temperature THbat is lower in a low temperature range where the battery temperature THbat is lower than the normal range, and is higher as the battery temperature THbat is higher in the high temperature range where the battery temperature THbat is higher than the normal range. To be done. Further, the charge limit power Win is increased as the charge capacity SOC is larger in a region where the charge capacity SOC is large, for example. Further, the discharge limited power Wout is increased as the charge capacity SOC is smaller in a region where the charge capacity SOC is small, for example.

  The electronic control unit 90 includes a hybrid control unit or a hybrid control unit 92 and an engagement control unit or an engagement control unit 94 in order to realize control functions for various controls in the vehicle 10.

  The hybrid control unit 92 controls the opening / closing of the electronic throttle valve, controls the fuel injection amount and the injection timing, and outputs the engine control command signal Se for controlling the ignition timing so that the target torque of the engine torque Te is obtained. The output control of the engine 12 is executed. Further, the hybrid control unit 92 outputs a rotating machine control command signal Sm for controlling the operation of the first rotating machine MG1 and the second rotating machine MG2 to the power control unit 18, and outputs the target torque of the MG1 torque Tg and the MG2 torque Tm. The output control of the first rotary machine MG1 and the second rotary machine MG2 is executed so that

  The hybrid control unit 92 calculates a drive torque (required drive torque) required at the vehicle speed V at that time from the accelerator opening θacc, and considers the charging request value and the like to achieve low fuel consumption and low exhaust gas amount operation. Thus, the required drive torque is generated from at least one of the engine 12, the first rotary machine MG1, and the second rotary machine MG2.

  The hybrid control unit 92 selectively establishes a motor traveling (EV traveling) mode or a hybrid traveling (HV traveling) mode (also referred to as an engine traveling (ENG traveling) mode) as a traveling mode according to a traveling state. The EV traveling mode enables EV traveling in which at least one of the first rotating machine MG1 and the second rotating machine MG2 is used as a driving force source for traveling while the engine 12 is stopped. It is a control mode. The HV traveling mode is a control mode that enables HV traveling (engine traveling) in which at least the engine 12 is used as a driving force source for traveling (that is, the power of the engine 12 is transmitted to the drive wheels 16 to travel). In addition, even in a mode in which the traveling of the vehicle 10 is not premised, such as a mode in which the power of the engine 12 is converted to electric power by the power generation of the first rotary machine MG1 and the battery unit 20 is exclusively charged with the electric power. Since 12 is in a driving state, it is included in the HV traveling mode.

  The engagement control unit 94 controls each engagement operation (operation state) of the clutch CL, the brake Br, and the clutch CLr based on the traveling mode established by the hybrid control unit 92. The engagement control unit 94 engages and / or releases each of the clutch CL, the brake Br, and the clutch CLr so that power transmission for traveling in the traveling mode established by the hybrid control unit 92 is possible. The hydraulic pressure control command signal Sp is output to the hydraulic pressure control circuit 54.

  Here, the travel modes that can be executed by the vehicle 10 will be described with reference to FIGS. 2 and 3 to 10. FIG. 2 is a chart showing each operating state of the clutch CL, the brake Br, and the clutch CLr in each traveling mode. In the diagram of FIG. 2, the open circles indicate the engagement of the engagement devices (CL, Br, CLr), the blanks indicate the release, and the open triangles indicate the engine brake (emblem) that brings the engine 12 in the operation stop state into rotation. (Also referred to as), it is shown that either one of them is engaged, or both are engaged. Further, "G" indicates that the rotating machine (MG1, MG2) mainly functions as a generator, and "M" causes the rotating machine (MG1, MG2) mainly to function as a motor during driving and mainly during generator. It is shown to function as. As shown in FIG. 2, the vehicle 10 can selectively realize an EV traveling mode and an HV traveling mode as traveling modes. The EV traveling mode is an independent drive EV mode that is a control mode in which EV traveling is possible using the second rotating machine MG2 as a sole driving force source, and an EV using the first rotating machine and the second rotating machine MG2 as a driving force source. It has two modes, a dual drive EV mode, which is a control mode capable of traveling. HV driving modes include overdrive (O / D) input split mode (hereinafter, O / DHV mode), underdrive (U / D) input split mode (hereinafter, U / DHV mode), and fixed stage mode. It has three modes.

  3 to 10 are collinear charts that can relatively represent the rotation speeds of the respective rotary elements RE1-RE6 in each of the first planetary mechanism 48 and the second planetary mechanism 50. In this collinear diagram, vertical lines Y1-Y4 representing the rotation speeds of the respective rotary elements are arranged in order from the left in the drawing, and the vertical line Y1 is the first sun gear which is the second rotary element RE2 connected to the first rotary machine MG1. The rotation speed of S1 is the vertical rotation speed of the first carrier CA1 which is the first rotation element RE1 and the rotation speed of the second ring gear R2 which is the sixth rotation element RE6, which are connected to each other by the vertical line Y3. Is the rotation speed of the first ring gear R1 that is the third rotation element RE3 that is connected to the drive gear 28, and the second carrier CA2 that is the fifth rotation element RE5 that is selectively connected to the case 22 via the brake Br. Regarding the rotation speed, the vertical line Y4 indicates the rotation speed of the second sun gear S2 that is the fourth rotation element RE4 connected to the engine 12. The arrow in the white square (□) indicates the MG1 torque Tg, the arrow in the white circle (◯) indicates the engine torque Te, and the arrow in the black circle () indicates the MG2 torque Tm. Further, the one in which the clutch CL that selectively connects the second carrier CA2 and the second ring gear R2 is shown in white is the released state of the clutch CL, and the one in which the clutch CL is hatched is the clutch CL. The respective engaged states are shown. Further, in the brake Br that selectively connects the second carrier CA2 to the case 22, the white diamond mark (⋄) shows the released state of the brake Br, and the black diamond mark (◆) shows the engaged state of the brake BR. . Further, in the clutch CLr that selectively connects the first ring gear R1 and the second carrier CA2, the white diamond mark (⋄) indicates the released state of the clutch CLr, and the black diamond mark (◆) indicates the engaged state of the clutch CLr. Shows. Further, a straight line relatively representing the rotation speed of the first planetary mechanism 48 is shown by a solid line, and a straight line relatively representing the rotation speed of the second planetary mechanism 50 is shown by a broken line. The arrow in the black circle (●) is the MG2 torque Tm by the second rotary machine MG2 driven by the electric power generated by the first rotary machine MG1 by the power of the engine 12 divided into the first rotary machine MG1. The direct torque component is not included. Further, the black diamond mark (◆) in the clutch CLr overlaps with the black circle mark (●), so that it is not shown in the drawing.

  FIG. 3 is an alignment chart in the single drive EV mode. The single drive EV mode is realized in a state where the clutch CL, the brake Br, and the clutch CLr are all released, as shown in FIG. In the single drive EV mode, the clutch CL and the brake Br are released, the differential of the second planetary mechanism 50 is allowed, and the second differential portion 46 is brought into the neutral state. The hybrid control unit 92 stops the operation of the engine 12 and outputs the traveling MG2 torque Tm from the second rotary machine MG2. FIG. 3 shows a case in which the second rotary machine MG2 is forwardly rotating (that is, in the rotating direction of the first ring gear R1 when the vehicle 10 is moving forward) and outputting positive torque. When moving backward, the second rotary machine MG2 is rotated in the reverse direction compared to when moving forward. While the vehicle is traveling, the first ring gear R1 coupled to the drive gear 28 is rotated in association with the rotation of the second rotary machine MG2 (here, the rotation of the drive wheels 16 is also the same). In the single drive EV mode, since the clutch CLr is further released, the engine 12 and the first rotary machine MG1 are not rotated together, and the engine rotation speed Ne and the MG1 rotation speed Ng can be set to zero. As a result, the drag loss in each of the engine 12 and the first rotary machine MG1 can be reduced, and the power consumption can be improved (that is, the power consumption can be suppressed). The hybrid control unit 92 maintains the MG1 rotation speed Ng at zero by feedback control. Alternatively, the hybrid control unit 92 executes a control (d-axis lock control) of supplying a current to the first rotating machine MG1 so that the rotation of the first rotating machine MG1 is fixed, and maintains the MG1 rotation speed Ng at zero. To do. Alternatively, even if the MG1 torque Tg is set to zero, it is not necessary to add the MG1 torque Tg when the MG1 rotation speed Ng can be maintained at zero due to the cogging torque of the first rotary machine MG1. Even if the control for maintaining the MG1 rotation speed Ng at zero is performed, since the first power transmission unit 24 is in the neutral state in which the reaction force of the MG1 torque Tg cannot be obtained, it does not affect the drive torque. Further, in the single drive EV mode, the first rotating machine MG1 may be idled with no load.

  In the single drive EV mode, the stopped engine 12 is not rotated and is brought into a stopped state at zero rotation. Therefore, regenerative control is performed by the second rotary machine MG2 during traveling in the single drive EV mode, that is, during single drive EV traveling. When performing, it is possible to take a large amount of regeneration. When the battery unit 20 is in a fully charged state and regenerative energy cannot be obtained during independent drive EV traveling, it may be considered to use engine braking together. When the engine brake is also used, as shown in FIG. 2, the clutch CL or the clutch CLr is engaged (refer to the combined use of the independent drive EV mode engine brake). When the clutch CL or the clutch CLr is engaged, the engine 12 is brought into a rotating state. In this state, when the engine rotation speed Ne is increased by the first rotating machine MG1, the engine brake can be applied. It should be noted that the engine speed Ne can be set to zero even when the engine 12 is being rotated, and in this case, EV traveling can be performed without applying engine braking. It is also possible to apply the engine brake by engaging the brake Br.

  FIG. 4 is an alignment chart in the dual drive EV mode. The dual drive EV mode is realized in a state in which the clutch CL and the brake Br are engaged and a state in which the clutch CLr is released, as shown in FIG. In the dual drive EV mode, the clutch CL and the brake Br are engaged, the differential of the second planetary mechanism 50 is restricted, and the rotation of the second carrier CA2 is stopped. Therefore, the rotation of any of the rotating elements of the second planetary mechanism 50 is stopped, and the second differential portion 46 is brought into the internal locked state. As a result, the engine 12 is stopped at zero rotation, and the first carrier CA1 connected to the second ring gear R2 is also fixed at zero rotation. When the first carrier CA1 is non-rotatably fixed, the reaction force torque of the MG1 torque Tg is obtained by the first carrier CA1. Therefore, the torque based on the MG1 torque Tg is mechanically output from the first ring gear R1 to drive the drive wheels. 16 can be transmitted. The hybrid control unit 92 stops the operation of the engine 12 and outputs the traveling MG1 torque Tg and MG2 torque Tm from the first rotary machine MG1 and the second rotary machine MG2, respectively. FIG. 4 shows a case during forward movement in which the second rotary machine MG2 outputs positive torque in positive rotation and the first rotary machine MG1 outputs negative torque in negative rotation. When the vehicle is moving backward, the first rotary machine MG1 and the second rotary machine MG2 are reversely rotated as compared to when moving forward.

  As shown in the description with reference to FIGS. 3 and 4, in the single drive EV mode, the vehicle 10 is driven only by the second rotary machine MG2, and in the dual drive EV mode, the first rotary machine MG1 and the second rotary machine MG2. It is possible to drive the vehicle 10 at. Therefore, in the case of EV traveling, when the load is low, the independent drive EV mode is established and the second rotary machine MG2 is independent travel, and when the load is high, the dual drive EV mode is established and the first rotary machine MG1 and Both drives are performed by the second rotating machine MG2. Regeneration during vehicle deceleration, including HV traveling, is mainly executed by the second rotary machine MG2.

  FIG. 5 is a collinear diagram in forward traveling in the O / DHV mode of the HV traveling mode. Forward traveling in the O / DHV mode (hereinafter, referred to as O / DHV mode (forward)) is realized with the clutch CL engaged and the brake Br and the clutch CLr released, as shown in FIG. . In the O / DHV mode (forward), the clutch CL is engaged and the brake Br is released, and the second differential portion 46 is in the direct coupling state, so the power of the engine 12 is coupled to the second ring gear R2. It is directly transmitted to the generated first carrier CA1. In addition, in the O / DHV mode (forward), the clutch CLr is released, and the first differential section 44 alone constitutes an electric continuously variable transmission. As a result, in the first power transmission unit 24, the power of the engine 12 input to the first carrier CA1 can be split into the first sun gear S1 and the first ring gear R1. That is, in the first power transmission unit 24, the engine direct torque is mechanically transmitted to the first ring gear R1 by taking the reaction force of the engine torque Te input to the first carrier CA1 by the first rotating machine MG1. At the same time, the power generated by the first rotary machine MG1 by the power of the engine 12 divided into the first rotary machine MG1 is transmitted to the second rotary machine MG2 via a predetermined electric path. The hybrid control unit 92 operates (operates) the engine 12, outputs the MG1 torque Tg, which is a reaction torque against the engine torque Te, by the power generation of the first rotating machine MG1, and outputs the MG1 torque Tg by the generated power of the first rotating machine MG1. The MG2 torque Tm is output from the two-rotation machine MG2. FIG. 5 shows a case in which the second rotary machine MG2 outputs forward positive torque in forward rotation and travels forward.

  FIG. 6 is an alignment chart in the U / DHV mode of the HV traveling mode. The U / DHV mode is realized in a state where the clutch CL and the brake Br are released and a state where the clutch CLr is engaged, as shown in FIG. In the U / DHV mode, the clutch CLr is engaged, and the first differential unit 44 and the second differential unit 46 form one differential mechanism. In addition, in the U / DHV mode, the clutch CL and the brake Br are released, and the first differential section 44 and the second differential section 46 as a whole are split in power by the first differential section 44 alone. An electric continuously variable transmission that operates at a power split ratio different from the ratio is configured. As a result, in the first power transmission unit 24, the power of the engine 12 input to the second sun gear S2 can be split into the first sun gear S1 and the first ring gear R1. That is, in the first power transmission unit 24, the engine direct torque is mechanically transmitted to the first ring gear R1 by taking the reaction force of the engine torque Te input to the second sun gear S2 by the first rotating machine MG1. At the same time, the power generated by the first rotary machine MG1 by the power of the engine 12 divided into the first rotary machine MG1 is transmitted to the second rotary machine MG2 via a predetermined electric path. The hybrid control unit 92 operates (operates) the engine 12, outputs the MG1 torque Tg, which is a reaction torque against the engine torque Te, by the power generation of the first rotating machine MG1, and outputs the MG1 torque Tg by the generated power of the first rotating machine MG1. The MG2 torque Tm is output from the two-rotation machine MG2.

  FIG. 7 is a collinear diagram in reverse traveling in the O / DHV mode of the HV traveling mode, and shows the rotation and torque of the engine 12 with respect to the configuration achieving the function as the electric continuously variable transmission. This is the case of the engine reverse rotation input, which is input by reversing to a negative value. As shown in FIG. 2, the reverse running (hereinafter referred to as the O / DHV mode reverse rotation input (reverse)) with the engine reverse rotation input in the O / DHV mode causes the clutch CL and the clutch CLr to be engaged while the brake Br is engaged. It is realized in the released state. In the O / DHV mode reverse rotation input (reverse), the clutch CL is released and the brake Br is engaged, and the second differential portion 46 is set to the reverse rotation speed change state of the engine 12, so the power of the engine 12 is , Negative rotation and negative torque are transmitted to the first carrier CA1 connected to the second ring gear R2. In addition, in the O / DHV mode reverse rotation input (reverse), the clutch CLr is released, and the first differential section 44 alone constitutes the electric continuously variable transmission. As a result, in the first power transmission unit 24, the power of the engine 12 reversely input to the first carrier CA1 can be split into the first sun gear S1 and the first ring gear R1. The hybrid control unit 92 operates (operates) the engine 12, outputs the MG1 torque Tg, which is a reaction torque against the engine torque Te, by the power generation of the first rotating machine MG1, and outputs the MG1 torque Tg by the generated power of the first rotating machine MG1. The MG2 torque Tm is output from the two-rotation machine MG2. FIG. 7 shows a case where the second rotary machine MG2 outputs a negative torque in a negative rotation and travels backward.

  FIG. 8 is a collinear diagram in the backward traveling in the O / DHV mode of the HV traveling mode, and shows the case of the engine forward rotation input. As shown in FIG. 2, the reverse running (hereinafter, referred to as the O / DHV mode forward rotation input (reverse)) in the O / DHV mode engine forward rotation input is in a state in which the clutch CL is engaged and the brake Br and the clutch are It is realized with CLr released. In the O / DHV mode normal rotation input (reverse drive), the clutch CL is engaged and the brake Br is released, and the second differential portion 46 is in the direct connection state, so the power of the engine 12 is the second ring gear. It is directly transmitted to the first carrier CA1 connected to R2. In addition, in the O / DHV mode forward rotation input (reverse drive), the clutch CLr is released, and the first differential portion 44 alone constitutes an electric continuously variable transmission. As a result, in the first power transmission unit 24, the power of the engine 12 input to the first carrier CA1 can be split into the first sun gear S1 and the first ring gear R1. The hybrid control unit 92 operates (operates) the engine 12, outputs the MG1 torque Tg, which is a reaction torque against the engine torque Te, by the power generation of the first rotating machine MG1, and outputs the MG1 torque Tg by the generated power of the first rotating machine MG1. The MG2 torque Tm is output from the two-rotation machine MG2. FIG. 8 shows a case where the second rotary machine MG2 outputs negative torque in negative rotation and is traveling in reverse.

  FIG. 9 is a collinear diagram in the fixed stage mode of the HV traveling mode, and is a case of direct connection in which the respective rotary elements of the first differential section 44 and the second differential section 46 are integrally rotated. The direct connection in the fixed stage mode (hereinafter referred to as the direct connection fixed stage mode) is realized with the clutch CL and the clutch CLr engaged and the brake Br released, as shown in FIG. In the direct connection fixed stage mode, the clutch CL is engaged and the brake Br is released, so that the second differential portion 46 is in the direct connection state. In addition, in the direct connection fixed stage mode, the clutch CLr is engaged, and the rotating elements of the first differential portion 44 and the second differential portion 46 are integrally rotated. As a result, in the first power transmission unit 24, the power of the engine 12 can be directly output from the first ring gear R1. The hybrid control unit 92 causes the engine 12 to output the engine torque Te for traveling. In this direct connection fixed stage mode, the first rotary machine MG1 can be driven by the electric power from the battery unit 20, and the power of the first rotary machine MG1 can be directly output from the first ring gear R1. Further, in the direct connection fixed stage mode, the second rotary machine MG2 can be driven by the electric power from the battery unit 20 and the power of the second rotary machine MG2 can be transmitted to the drive wheels 16. Therefore, the hybrid control unit 92 may output the running torque from at least one of the first rotating machine MG1 and the second rotating machine MG2, in addition to outputting the engine torque Te. That is, in the direct connection fixed stage mode, the vehicle 10 may be driven only by the engine 12, or torque assist may be performed by the first rotary machine MG1 and / or the second rotary machine MG2.

  FIG. 10 is a collinear diagram in the fixed stage mode of the HV traveling mode, and shows a case of fixing the output shaft in which the first ring gear R1 is fixed so as not to rotate. The output shaft fixing in the fixed stage mode (hereinafter referred to as the output shaft fixed stage mode) is realized with the brake Br and the clutch CLr engaged and the clutch CL released, as shown in FIG. In the output shaft fixed stage mode, the clutch CLr is engaged, and the first differential unit 44 and the second differential unit 46 form one differential mechanism. In addition, in the output shaft fixed stage mode, the brake Br is engaged and the clutch CL is released, so that the first ring gear R1 is fixed so as not to rotate. As a result, in the first power transmission unit 24, the reaction force of the power of the engine 12 input to the second sun gear S2 can be taken by the first rotary machine MG1. Therefore, in the output shaft fixed stage mode, the battery unit 20 can be charged with the electric power generated by the first rotating machine MG1 by the power of the engine 12. The hybrid control unit 92 operates (operates) the engine 12, takes a reaction force against the power of the engine 12 by the power generation of the first rotary machine MG1, and outputs the generated power of the first rotary machine MG1 via the power control unit 18. The battery unit 20 is charged. The output shaft fixed stage mode is a mode in which the battery unit 20 is exclusively charged when the vehicle 10 is stopped because the first ring gear R1 is fixed so as not to rotate. As shown in the description using FIGS. 9 and 10, the clutch CLr is engaged in the direct connection fixed stage mode or the output shaft fixed stage mode of the HV traveling mode.

  FIG. 11 is a diagram showing an example of a torque ratio (Tg / Te) of the MG1 torque Tg to the engine torque Te and a torque ratio (Tm / Te) of the MG2 torque Tm to the engine torque Te during engine running in forward running. Is. This MG2 torque Tm is the MG2 torque Tm generated by the second rotary machine MG2 driven by the power generated by the first rotary machine MG1 by the power of the engine 12. In FIG. 11, in a region where the reduction ratio I (= Ne / No) of the first power transmission unit 24 is relatively large, the torque ratio (Tm / Te) in the U / DHV mode is smaller than that in the O / DHV mode. It Therefore, in the region where the reduction gear ratio I is relatively large, the load on the second rotating machine MG2 with respect to the engine torque Te can be reduced by establishing the U / DHV mode. For example, if the U / DHV mode is established when the engine 12 using a relatively large reduction gear ratio I has a high load, the MG2 torque Tm can be kept low. This means that the U / DHV mode can cope with a larger reduction ratio I at the maximum value of the MG2 torque Tm than the O / DHV mode, and the range of the HV traveling mode can be expanded. . On the other hand, in a relatively small region where the reduction ratio I is smaller than "1", the absolute value of the torque ratio (Tm / Te) in the U / DHV mode is larger than that in the O / DHV mode. Further, the state where the torque ratio (Tm / Te) has a negative value is a power circulation state in which the second rotary machine MG2 generates power and the generated power is supplied to the first rotary machine MG1. It is desirable that the power circulation state is avoided or suppressed as much as possible. Therefore, in the region where the reduction ratio I is relatively small, the power circulation power can be reduced by establishing the O / DHV mode. By switching between the U / DHV mode and the O / DHV mode according to the reduction gear ratio I, the engine power can be transmitted by the second rotary machine MG2 having a lower torque.

  FIG. 12 shows a rotation speed ratio of the MG1 rotation speed Ng to the engine rotation speed Ne (Ng / Ne) and a rotation speed ratio of the MG2 rotation speed Nm to the engine rotation speed Ne (Nm / Ne) while the engine is running forward. FIG. In FIG. 12, in a relatively large region where the reduction ratio I of the first power transmission unit 24 is larger than “1”, the U / DHV mode has a rotational speed ratio (Ng / Ne) higher than the O / DHV mode. The absolute value of is reduced. Therefore, in a region where the reduction gear ratio I is relatively large, the U / DHV mode is established to suppress an increase in the MG1 rotation speed Ng. For example, if the U / DHV mode is established at the time of starting using a relatively large reduction ratio I, the MG1 rotation speed Ng can be suppressed to be low. On the other hand, in a relatively small region where the reduction gear ratio I is smaller than "1", the absolute value of the rotation speed ratio (Ng / Ne) is larger in the U / DHV mode than in the O / DHV mode. Therefore, in a region where the reduction gear ratio I is relatively small, the O / DHV mode is established to suppress an increase in the MG1 rotation speed Ng. By switching between the U / DHV mode and the O / DHV mode according to the reduction gear ratio I, the engine power can be transmitted by the first rotating machine MG1 having a lower rotation speed.

  FIG. 13 is a diagram showing an example of an output ratio (Pg / Pe) of the MG1 power Pg to the engine power Pe and an output ratio (Pm / Pe) of the MG2 power Pm to the engine power Pe during the engine running in forward running. Is. 13, in a region where the reduction ratio I of the first power transmission unit 24 is relatively large, the output ratio (Pg / Pe) and the output ratio (Pm / Pe) in the U / DHV mode are higher than those in the O / DHV mode. Each absolute value of is reduced. Therefore, in the region where the reduction gear ratio I is relatively large, the increase of the MG1 power Pg and the increase of the MG2 power Pm can be suppressed by establishing the U / DHV mode. On the other hand, in a relatively small region where the reduction ratio I is smaller than “1”, the output ratio (Pg / Pe) and the output ratio (Pm / Pe) in the U / DHV mode are higher than those in the O / DHV mode. Each absolute value of is increased. The state in which the output ratio (Pm / Pe) is a negative value (that is, the output ratio (Pg / Pe) is a positive value) is the power circulation state. Therefore, in the region where the reduction ratio I is relatively small, the power circulation power can be reduced by establishing the O / DHV mode. By switching between the U / DHV mode and the O / DHV mode according to the speed reduction ratio I, the engine power can be transmitted by the rotary machines MG1 and MG2 having a lower output (low power).

  As shown in the description with reference to FIGS. 11 to 13, the U / DHV mode is established when the engine 12 using a relatively large reduction ratio I has a high load, and the low load of the engine 12 using a relatively small reduction ratio I is established. By properly using the U / DHV mode and the O / DHV mode so as to establish the O / DHV mode at the time of high vehicle speed or high vehicle speed, an increase in each torque or each rotational speed of the rotating machines MG1, MG2 is prevented or suppressed, Power circulation power is reduced at high vehicle speeds. This reduces energy conversion loss in the electric path and leads to improvement in fuel consumption. Alternatively, it leads to downsizing of the rotary machines MG1 and MG2.

  In both the U / DHV mode and the O / DHV mode, the first power transmission unit 24 is made to function as an electric continuously variable transmission. The state in which the speed reduction ratio I of the first power transmission unit 24 is "1" is equivalent to the state in the direct coupling fixed stage mode in which both the clutch CL and the clutch CLr are engaged (see FIG. 9). Therefore, preferably, the hybrid control unit 92 switches between the O / DHV mode (forward movement) in which the clutch CL is engaged and the U / DHV mode in which the clutch CLr is engaged when the reduction ratio I is "1". This is executed by switching the operating states of the clutch CL and the clutch CLr in the synchronous state of ".

  FIG. 14 is a diagram showing an example of a traveling mode switching map used for switching control between engine traveling and motor traveling. This travel mode switching map has a boundary line between the engine travel area and the motor travel area as a variable with the vehicle speed V and the travel load of the vehicle 10 (hereinafter, referred to as vehicle load) (for example, required drive torque) as a variable or experimentally beforehand. It is a relationship that is sought and stored by design (that is, predetermined). FIG. 14 shows the state transition of the power transmission device 14 (that is, the switching of the traveling mode of the vehicle 10) during CS (Charge Sustain) traveling, in which the vehicle travels while maintaining the battery capacity SOC. This FIG. 14 is used when the vehicle 10 is, for example, a hybrid vehicle in which the battery capacity SOC is originally set to be relatively small. Alternatively, FIG. 14 is used when the mode in which the vehicle 10 holds the battery capacity SOC is established in the plug-in hybrid vehicle, the range extended vehicle, or the like in which the vehicle capacity SOC is originally set to be relatively large.

  In FIG. 14, in order to facilitate the U / DHV mode when the load is high and to easily establish the O / DHV mode when the load is low or when the vehicle speed is high, the range of each traveling mode according to the traveling state such as the vehicle speed V and the vehicle load. Is set. Further, in the direct connection fixed stage mode, since there is no power transmission through the rotary machines MG1 and MG2, heat loss due to conversion of mechanical energy and electric energy is eliminated. Therefore, it is advantageous for improving fuel efficiency and avoiding heat generation. Therefore, the area of the direct connection fixed stage mode is set so that the direct connection fixed stage mode is positively established at the time of high load such as towing or high vehicle speed. Further, when the battery unit 20 can carry out electric power (or when warming up of the engine 12 or warming up of each device by the operation of the engine 12 is completed), in a region where the operating efficiency of the engine 12 deteriorates, The power running of the second rotary machine MG2 is performed during EV running. Therefore, the region of the single drive EV mode is set in the region where the vehicle speed and the load are low as shown by the broken line. When the vehicle load is negative, in the U / DHV mode or the O / DHV mode, deceleration travel is performed by applying engine braking using the negative torque of the engine 12. When the battery unit 20 can accept the electric power, the second rotary machine MG2 is regenerated during EV traveling. Therefore, the region of the single drive EV mode is set in the region where the vehicle load becomes negative as shown by the alternate long and short dash line. In the traveling mode switching map for CS traveling set in this way, the U / DHV mode is established for both forward and backward traveling when starting, for example. As a result, the engine power Pe can be used more effectively, so that the starting acceleration performance is improved. As the vehicle speed V increases during forward traveling, the speed reduction ratio I of the first power transmission unit 24 becomes close to "1". In this state, the direct connection fixed stage mode is entered. In low-speed traveling, the engine speed Ne becomes extremely low, so the U / DHV mode is directly changed to the O / DHV mode. When the driver operates the switch for selecting EV traveling and EV traveling is selected, the single drive EV mode is established in the region shown by the broken line.

  It should be noted that when the engine 12 that is stopped is restarted while the motor is traveling, that is, in the traveling modes shown in FIGS. 3 and 4, a direct injection engine is used as the engine 12 to achieve a predetermined engine speed Ne. It is possible to start the normal engine 12 in which fuel is injected and ignite in the cylinder after reaching it, and to start ignition of the engine 12 in which fuel is injected and ignited in the cylinder from the beginning of rotation of the engine 12, which is also called early ignition start. Has become. When the engine 12 is started, the engine crank angle sensor 86 selects a cylinder having a predetermined crank angle θcr, that is, an expansion stroke, and the fuel is directly injected into the selected cylinder to start the ignition of the engine 12. It is possible.

  Returning to FIG. 1, the electronic control device 90 includes a power limit determination unit 96, an engine start determination unit 98, and a differential rotation calculation unit 100 in addition to the hybrid control unit 92 and the engagement control unit 94 described above.

  When the electronic control unit 90 determines that the vehicle is EV traveling, that is, EV traveling, the power limitation determination unit 96 determines the charging limitation power Win that defines the limitation of the charging power and the discharge limitation that defines the limitation of the output power of the battery unit 20. The power Wout is calculated, and it is determined whether the calculated input / output limit power of the battery unit 20, that is, the charge limit power Win or the discharge limit power Wout is equal to or greater than a predetermined value stored in advance. When the input / output limited power is equal to or greater than the predetermined value, the differential rotation calculation unit 100 determines the differential rotation speed Nd of the clutch CLr, that is, the rotational speed difference between the first ring gear R1 and the second carrier CA2 as a predetermined vehicle speed with drivability priority. It is set by applying the actual vehicle speed V to the relationship between V and the differential rotation speed Nd.

  Here, the drivability priority, the lag reduction, and the power consumption priority, which are shown as an example of setting the target value of the differential rotation in FIG. 15, will be described. An example of the drivability priority is shown in FIG. 15 as a straight line in which the differential rotation speed Nd is zero regardless of the increase in the vehicle speed V. The drivability priority is set in accordance with the driver's intention in which the responsiveness and smoothness to the operation of the driver of the vehicle 10 are prioritized, and the target value of the differential rotation speed Nd of the clutch CLr is set to 0 during EV running. As soon as the vehicle travels and a signal equal to or greater than a predetermined accelerator opening degree is received, the clutch CLr can be engaged and the engine 12 can be started immediately, so that it is possible to shorten the response time to the driver's request. . Further, as described above, the input / output limit power of the battery unit 20, that is, the charge limit power Win or the discharge limit power Wout is stored in advance, except for the case where the sports mode is selected by the driver. It is also applied when the value is equal to or more than the predetermined value. When the synchronization time is shortened, the power output and power input are increased. When the input / output limited power of the battery unit 20 is equal to or greater than the predetermined value, the differential rotation speed Nd is set to, for example, substantially zero in advance, thereby suppressing the delay in synchronization of the differential rotation of the clutch CLr due to the input / output limited power. To be done. The electricity cost priority is set as a straight line having the largest differential rotation speed Nd with respect to the vehicle speed V, as indicated by the solid line in FIG. The target value of the differential rotation speed Nd of the clutch CLr is set such that the engine rotation speed Ne and the rotation speed Ng of the first rotary machine MG1 are set even when the vehicle speed V increases, for example, when the EV travels. It is set to zero. As a result, the loss due to the turning of the first rotary machine MG1 is suppressed to a small level. Further, it may be set so as to reduce the total by adding the losses due to other factors to be mixed up. In FIG. 15, the target value of the differential rotation speed Nd of the clutch CLr when the lag is shortened is shown by a chain line and is set between drivability priority and electricity cost priority. The target values of drivability priority, lag reduction, and electricity cost priority are all shown as straight lines, but they do not have to be straight lines. Further, the drivability priority may not be set to the complete engagement of the clutch CLr, and the power consumption priority may be set to a setting close to that, instead of the complete release of the clutch CLr. It is also possible to set a plurality of lag reduction settings.

  Returning to the calculation of the differential rotation target value described above, assuming that the differential rotation speed Nd is the target value set as the drivability priority, the hybrid control unit 92 sets the differential rotation speed Nm set to the rotation speed Nm of the second rotary machine MG2. From the above, for example, the rotational speed Ng of the first rotary machine MG1 for setting the set differential rotation Nd is calculated based on the mutual relational expression of the rotational speeds of the rotary elements RE1 to RE6 stored in advance, that is, the collinear diagram. To do. The hybrid control unit 92 controls the rotation speed Ng of the first rotating machine MG1 and sets the differential rotation Nd of the clutch CLr to zero in the case of the single drive EV traveling. Further, in the case of traveling in the dual drive EV mode, a control operation for releasing the clutch CL and the brake Br is added at the time when the accelerator opening signal of a predetermined value or more is generated. From this point onward, the control operation is the same as that of the single drive EV traveling, and therefore the case of the single drive EV traveling will be described. The electronic control unit 90 determines that the vehicle is EV traveling, and the power limit determination unit 96 determines that the input / output limited power of the battery unit 20 that defines the limitation of the charging power, that is, the charge limited power Win or the discharge limited power Wout. If it is determined that the value is less than the predetermined value stored in advance, the electronic control unit 90 determines whether the driving mode selection switch 82 is selected in the sports mode. When the sport mode is selected, the drivability priority differential rotation target is set. When the sports mode is not selected, the electronic control unit 90 determines whether the eco mode is selected. When the eco mode is selected, the differential rotation speed calculation unit 100 sets the power consumption priority based on the relationship between the vehicle speed V and the differential rotation speed Nd of the clutch CLr, which is stored in advance as an example in FIG. Set the target value. The hybrid control unit 92 controls the rotation speed Ng of the first rotating machine to a value that becomes a target value of the differential rotation Nd, based on an instruction from the electronic control unit 90. When the eco mode is not selected, that is, in the normal mode, the engine start determination unit 98 injects fuel into the cylinders of the stopped engine 12 and starts the engine 12 by igniting the ignition start. Determine whether it is possible to do. When the engine 12 can be started by ignition, the differential rotation calculation unit 100 sets a target value set as power consumption priority based on the relationship between the vehicle speed V and the differential rotation Nd of the clutch CLr stored in advance, and the hybrid The control unit 92 controls the rotation speed Ng of the first rotating machine to a value that becomes a target value of the differential rotation Nd, based on an instruction from the electronic control unit 90. When the ignition start of the engine 12 is difficult, the differential rotation calculation unit 100 sets the lag shortening differential rotation target value that shortens the delay time of the engine start as the differential rotation Nd of the clutch CLr, and the hybrid control unit 92 sets the electronic control unit. Based on the instruction of 90, the rotation speed Ng of the first rotating machine is controlled to a value that becomes the target value of the differential rotation Nd. When the drivability is prioritized, the lag reduction differential rotation is set such that the drivability priority differential rotation, that is, the differential rotation Nd is zero or close to zero. When it is difficult to start the ignition of the engine 12, for example, the high engine water temperature Tw lowers the air density in the expansion stroke for fuel injection and ignition, so the explosive power decreases. Alternatively, there is an increase in friction due to running out of oil in the sliding portion of the engine 12.

  FIG. 18 is a flowchart illustrating an example of a control operation of the electronic control unit 90, that is, an example of a control operation for setting the differential rotation speed of the second clutch CLr based on a request for the starting responsiveness of the engine 12. To be executed. In S10 corresponding to the function of the electronic control unit 90, it is determined whether the traveling state of the vehicle 10 is EV traveling. When this determination is denied, the determination from S10 is repeated. When the determination in S10 is affirmative, it is determined in S20 corresponding to the function of the power limitation determination unit 96 whether the input / output limited power of the battery unit 20 is equal to or greater than the predetermined value. If the determination in S20 is affirmative, drivability priority differential rotation, that is, zero is calculated in S60 corresponding to the function of the differential rotation calculation unit 100, and in S90 corresponding to the functions of the electronic control device 90 and the hybrid control unit 92. The differential rotation is controlled. When the determination in S20 is negative, in S30 corresponding to the function of the electronic control device 90, it is determined whether or not the sport mode is set. When the determination in S30 is affirmative, drivability priority differential rotation, that is, zero is calculated in S60, and differential rotation control is performed in S90 corresponding to the functions of the electronic control unit 90 and the hybrid control unit 92. When the determination in S30 is negative, in S40 corresponding to the function of the electronic control device 90, it is determined whether or not the eco mode is set. When this determination is affirmed, in S80 corresponding to the function of the differential rotation calculation unit 100, the target value of the differential rotation Nd with priority on electricity consumption is calculated based on the vehicle speed V, and the electronic control unit 90 and the hybrid control unit 92 are operated. In S90 corresponding to the function, differential rotation control is performed. When the determination in S40 is negative, in S50 corresponding to the function of the engine start determination unit 98, it is determined whether the ignition start of the engine 12 is possible. When the determination in S50 is affirmative, in S80 corresponding to the function of the differential rotation calculation unit 100, the target value of the power consumption priority differential rotation Nd is calculated based on the vehicle speed V, and the electronic control unit 90 and the hybrid control unit 92 are operated. In S90 corresponding to the function, differential rotation control is performed. If the determination in S50 is negative, the lag reduction differential rotation target value is calculated based on the vehicle speed V in S70, which corresponds to the function of the differential rotation calculation unit 100, and corresponds to the functions of the electronic control device 90 and the hybrid control unit 92. In S90, the differential rotation is controlled so as to reach the target value calculated in S60, S60, or S80.

  The time chart of FIG. 17 is an example in which the accelerator 12 is depressed in the single drive EV traveling, and then the transition to the U / D input split, which is the HV traveling, is performed, and the ignition start of the engine 12 is possible. This shows the case. FIG. 17 is an example in which, in the flowchart of FIG. 16, it is determined that the ignition start of the engine 12 in S40 is possible, and the differential rotation with priority on electricity consumption is set. At time t0, the accelerator is depressed more than a predetermined value. As a result, the U / DHV mode is judged from the single drive EV running, and the rotation speed Ng of the first rotary machine MG1 starts to increase in order to synchronize the clutch CLr, that is, to make the differential rotation zero. At the same time, the second rotary machine MG2 coupled to the driven shaft 32 also increases the torque to increase the vehicle acceleration. By increasing the increase in the torque, the driver feels the response of the vehicle 10. I am letting you. When the synchronization of the clutch CLr is completed, the engagement of the clutch CLr is started. Further, since ignition start is possible, the torque reduction in the driven shaft 32 due to the start of the engine 12 becomes small. As a result, the second rotary machine MG2 outputs the maximum torque at the time point t2 at the time point t1, for example, in response to the throttle (not shown) being fully opened, and the vehicle acceleration of the vehicle 10 is increased. It is possible to make the driver feel that the responsiveness of the vehicle 10 is good. The desired torque Tm may be set instead of the maximum torque output. When the engagement of the clutch CLr is completed at time t2, ignition start is started in which fuel is injected and ignited in the cylinder in the expansion stroke of the engine 12 to start the engine 12 by itself. In this case, the first rotary machine MG1 may slightly generate torque to assist. In FIG. 17, from the time point t2 to the time point t3, the first rotary machine MG1 outputs a negative torque to the extent that the inertia torque of the first rotary machine MG1 is not transmitted to the rotation of the engine 12. At time t3, the start of the engine 12 is completed, the torque Te starts to be output from the engine 12, a downshift is started, and the engine rotation speed Ne is increased. When the torque requested by the driver is secured at time t4, the downshift is completed. When ignition can be started, the accelerator opening degree is required in order to sequentially perform clutch CLr synchronization, engagement, engine start, and downshift from the depression of the accelerator, that is, the input of the accelerator opening signal to the completion of the downshift. Although it takes time from the input of the signal to the completion of the downshift, the torque of the second rotary machine MG2 can be increased so that the driver does not feel the deterioration of the responsiveness.

  The time chart of FIG. 18 is another example of the case where the accelerator is depressed in the single drive EV traveling, and then the transition to the U / D input split which is the HV traveling is performed, and the ignition start of the engine 12 is started. Shows the case that cannot be done. FIG. 18 is an example in which in the flowchart of FIG. 16, it is determined that the ignition start of the engine 12 cannot be performed in S40, and the differential rotation for lag shortening is set. In this drawing, for simplification, the target value of the differential rotation Nd is explained as zero. When the differential rotation is set to a time other than zero, the time required for the differential rotation Nd to become zero is added from the differential rotation Nd for lag reduction. At t10, the accelerator is depressed. The rotation speed Ng of the first rotating machine MG1 has already reached the rotation speed Ng at which the differential rotation Nd is zero, that is, the engagement speed of the clutch CLr is immediately started. Further, from time t10 to time t11, the second rotary machine MG2 torque is increased to make the driver feel responsiveness. However, since the ignition start cannot be performed, the decrease in the output shaft torque due to the start of the engine 12 becomes larger than that in FIG. 17, and the second rotary machine MG2 outputs the torque excluding this torque decrease. Therefore, the vehicle acceleration is smaller than that in FIG. At time t11, cranking of the engine 12 by the first rotating machine MG1 is started. At time t12, ignition of the engine 12 is started, and the first rotating machine MG1 continues cranking. Further, from time t11 to time t13, the torque of the second rotating machine MG2 is increased because the vehicle acceleration does not decrease. When the engine 12 is completely started at time t13, a downshift is started to increase the engine rotation speed Ne, and at time t14, the downshift is completed. When the ignition start cannot be performed, it is possible to shorten the time from the depression of the accelerator, that is, the input of the accelerator opening signal to the completion of the downshift. Therefore, the increase in the acceleration of the vehicle from t11 is as shown in FIG. Although lower than the comparison, the driver does not feel a decrease in responsiveness. Although not shown for simplification, the control of compensating the vibration torque associated with the start of the engine 12 by the first rotary machine MG1 and the second rotary machine MG2 is performed simultaneously with the control of FIGS. 17 and 18. You can also

  As described above, according to the present embodiment, the first planetary mechanism 48 and the first rotating machine MG1 arranged on the input shaft 42, and the second rotating machine arranged on the rotor shaft 56 different from the input shaft 42. Between the engine 12 and the first planetary mechanism 48, a multi-axis electric continuously variable transmission having an MG2, a second planetary mechanism 50, a first brake Br for shifting, and a first clutch CL. And a clutch CLr provided between the electric continuously variable transmission and the stepless transmission, and injects fuel into a cylinder of the engine 12 when the engine 12 is stopped. In the electronic control unit 90 of the vehicle 10 capable of starting and igniting the engine 12 by igniting and then igniting, if ignition is impossible until a predetermined engine speed Ne is reached, ignition can be immediately started. Compared with the case, the clutch CLr By setting the differential rotation speed Nd to be small, it is possible to shorten the time until the second clutch CLr is synchronized, that is, the time until the second clutch is started to be engaged, when the driver's acceleration request occurs. This makes it possible to shorten the time from the acceleration request to the start of the engine 12 when the driver makes an acceleration request, and it is possible to prevent the driver from feeling deterioration of drivability. Further, when ignition start is possible, by setting the differential rotation speed Nd of the second clutch CLr to a large value, the loss caused by the rotation of the engine 12 is reduced, and the power consumption, that is, the power consumption is improved. In this case, when the driver's acceleration request is generated, after the second clutch CLr is synchronized, the ignition start can be performed without waiting for the engine 12 to reach a predetermined rotation speed, and the driver's drivability is improved. It is suppressed that you feel the deterioration of.

  Although the embodiments of the present invention have been described in detail with reference to the drawings, the present invention can be applied to other aspects.

  In the first embodiment, when the input / output limit power of the battery unit 20 is equal to or greater than the predetermined value, the differential rotation speed Nd of the clutch CLr is set to zero which is the predetermined target value set as the drivability priority. . This is to prevent the synchronization time of the clutch CLr from becoming long due to the large input / output limit power of the battery unit 20, but the invention is not limited to this. For example, the differential rotation speed Nd of the clutch CLr may be set smaller as the input / output limit power of the battery unit 20 is larger. In this way, the engagement and downshift of the clutch CLr are executed without changing the synchronization time of the clutch CLr depending on the magnitude of the battery input / output limited power, which makes the driver feel the deterioration of drivability. Is effectively suppressed.

  Further, in the first embodiment, the setting of the differential rotation speed Nd of the clutch CLr is changed by the operation of the operation mode selection switch 82 by the driver in the sports mode, the eco mode, or the normal mode, but this is not particularly limited. Absent. For example, the setting of the differential rotation Nd of the clutch CLr may be changed when the sequential mode or the M mode is selected by a shift lever (not shown). Alternatively, the driving orientation may be read from the history of detected values such as vehicle acceleration, and the setting of the differential rotation Nd of the clutch CLr may be changed. As a result, it is possible to effectively prevent the driver from feeling the deterioration of drivability and also to make the driver feel good drivability.

  Further, in the first embodiment, the setting of the differential rotation speed Nd of the clutch CLr is set to zero, that is, the synchronization is completed, and the engagement of the clutch CLr is completed, so that the time until the engine 12 is started when the acceleration request of the driver occurs. Can be shortened. As a result, it is possible to effectively prevent the driver from feeling the deterioration of drivability and also to make the driver feel good drivability.

  The above description is merely one embodiment, and the present invention can be implemented in various modified and improved modes based on the knowledge of those skilled in the art.

10: Vehicle (hybrid vehicle)
12: engine 42: input shaft (first shaft)
48: First planetary mechanism 50: Second planetary mechanism 56: Rotor shaft (second shaft)
90: Electronic control device (control device)
MG1: 1st rotary machine MG2: 2nd rotary machine CL, CLr: Clutch (1st clutch, 2nd clutch)
Br: brake (first brake)
Nd: Differential rotation

Claims (1)

A multi-axis electric continuously variable transmission having a first planetary mechanism and a first rotating machine arranged on a first shaft, and a second rotating machine arranged on a second shaft different from the first shaft. Machine (THS),
A stepped transmission having a second planetary mechanism, a first brake and a first clutch for shifting, and provided between the engine and the first planetary mechanism;
A second clutch provided between the electric continuously variable transmission and the stepped transmission;
A control device for a hybrid vehicle capable of ignition start, which starts the engine by injecting fuel into a cylinder to ignite when the engine is stopped,
When the ignition start of the engine is not possible during running of the electric motor based on one or both of the first rotating machine and the second rotating machine without driving the engine, the ignition start is performed. A control device for a hybrid vehicle, characterized in that the differential rotation of the second clutch is made smaller than possible.

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