JP7067345B2 - Vehicle control device - Google Patents

Description

The present invention relates to a vehicle control device including a power source and an automatic transmission that constitutes a part of a power transmission path that transmits the power of the power source.

A vehicle control device including a power source and an automatic transmission that forms part of a power transmission path between the power source and the drive wheels is well known. For example, the control device for a hybrid vehicle described in Patent Document 1 is that. In Patent Document 1, feedback control is performed so that the change speed of the rotation speed of the input rotating member as a value indicating the rotational state of the input rotating member of the automatic transmission becomes a target value at the time of shifting transition of the automatic transmission. It is disclosed to control the input torque to the automatic transmission.

Japanese Unexamined Patent Publication No. 2014-223888

By the way, when the input torque to the automatic transmission is controlled by feedback control during the shift transition of the automatic transmission, the input torque to the automatic transmission is when the rotation speed of the input rotating member is synchronized with the synchronous rotation speed after the shift. May deviate from the required input torque. In such a case, the input torque to the automatic transmission deviating from the required input torque is returned to the required input torque after the rotation speed of the input rotating member is synchronized. When returning the input torque to the automatic transmission to the required input torque, it is desirable to gradually change the input torque toward the required input torque at a predetermined rate in order to avoid a large change in the input torque. However, if the required input torque after synchronization is reduced due to the large deceleration of the vehicle after the upshift in the power-off state of the automatic transmission, that is, it is increased to the negative side, it is within a predetermined time. The input torque may not be able to return to the required input torque.

The present invention has been made in the background of the above circumstances, and an object thereof is to return the input torque to the required input torque as slowly as possible after the upshift in the power-off state of the automatic transmission. It is an object of the present invention to provide a vehicle control device capable of suppressing a situation in which an input torque cannot return to a required input torque within a predetermined time.

The gist of the first invention is (a) a control device for a vehicle including a power source and an automatic transmission that constitutes a part of a power transmission path between the power source and the drive wheels. (B) At the time of upshifting in the power-off state of the automatic transmission, a value representing the rotation state of the input rotating member of the automatic transmission is input during the inertia phase in the shift transition of the automatic transmission. A feedback control unit that controls the input torque to the automatic transmission by feedback control so as to be a target value for changing the rotation speed of the rotating member toward the synchronous rotation speed after the upshift, and (c) the automatic The state determination unit for determining whether or not the rotation speed of the input rotation member of the transmission is synchronized with the synchronous rotation speed after the upshift, and (d) the rotation speed of the input rotation member of the automatic transmission are When it is determined that the state is synchronized with the synchronous rotation speed after the upshift, the return control for gradually changing the input torque to the automatic transmission toward the required input torque at a predetermined rate is executed. The control unit and (e) set the absolute value of the predetermined rate when it becomes a negative value in the return control after the upshift to a larger value when the deceleration of the vehicle is large than when it is small. It is to include a rate setting unit to be used.

Further, in the second invention, in the vehicle control device according to the first invention, the vehicle includes a rotating machine that functions as the power source, and the required input torque after the upshift is the same. The larger the deceleration of the vehicle is, the larger the deceleration of the vehicle is to the negative side so that the deceleration of the vehicle is realized by the braking torque by the regenerative control of the rotating machine.

The third invention is the vehicle control device according to the first invention, wherein the vehicle has an engine that functions as the power source, a differential mechanism in which the engine is connected so as to be able to transmit power, and the above. An electric transmission mechanism having a first rotating machine connected to the differential mechanism so as to be able to transmit power, and controlling the operating state of the first rotating machine to control the differential state of the differential mechanism. A hybrid vehicle including a second rotating machine that functions as a power source and is connected to an output rotating member of the electric speed change mechanism so as to be able to transmit power. The automatic transmission is the electric speed change mechanism. It is a mechanical speed change mechanism that constitutes a part of a power transmission path between the output rotating member of the above and each of a plurality of gear stages, and the feedback control unit is the mechanical speed change mechanism. At the time of shifting, the output torque of the engine and the mechanical shifting so that the value representing the rotational state of the input rotating member and the value representing the rotational state of the engine are the respective target values in the inertia phase. The output torque of the first rotary machine and the output torque of the second rotary machine are controlled by feedback control based on the transmission torque transmitted by the mechanism, and the return control unit is the mechanical speed change mechanism. When the rotation speed of the input rotation member of the above is in a state synchronized with the synchronous rotation speed after the shift, the return control is to be executed.

Further, in the fourth invention, in the vehicle control device according to the third invention, the deceleration of the vehicle is the first factor in the required input torque after the upshift in the power-off state of the mechanical speed change mechanism. The larger the deceleration of the vehicle, the larger the deceleration to the negative side, as realized by the braking torque by the regenerative control of the two-rotating machine.

Further, the fifth invention is the vehicle control device according to any one of the first to fourth inventions, wherein the automatic transmission is any one of a plurality of hydraulic engagement devices. It is a stepped transmission in which any one of a plurality of gear stages is formed by the engagement of the engaging device, and the rate setting unit is negative in the return control after the upshift. The absolute value of the predetermined rate at the time of becoming a value is set to a larger value as the temperature of the hydraulic oil that operates the engaging device becomes higher.

Further, the sixth invention is the vehicle control device according to any one of the first to fifth inventions, wherein the rate setting unit is negative in the return control after the upshift. The absolute value of the predetermined rate at the time of becoming a value is set to a larger value as the input torque to the automatic transmission at the time when the return control is started becomes larger.

Further, the seventh invention is the vehicle control device according to any one of the first to sixth inventions, wherein the rate setting unit has the predetermined rate according to the deceleration of the vehicle. The setting is to reduce the change range of the predetermined rate as the vehicle speed decreases.

According to the first invention, the input to the automatic transmission is input after the rotation speed of the input rotating member of the automatic transmission is synchronized with the synchronous rotation speed after the upshift in the power-off state of the automatic transmission. Since the absolute value of the predetermined rate when it becomes a negative value when executing the return control that changes the torque toward the required input torque is set to a larger value when the deceleration of the vehicle is large than when it is small. When the deceleration of the vehicle is relatively small, the input torque is gradually brought closer to the required input torque. Further, when the deceleration of the vehicle is relatively large, the input torque is quickly brought close to the required input torque. Therefore, after an upshift in the power-off state of the automatic transmission, the input torque cannot return to the required input torque within a predetermined time while returning the input torque to the required input torque as slowly as possible. It can be suppressed.

Further, according to the second invention, the required input torque after the upshift in the power-off state of the automatic transmission is increased to the negative side as the deceleration of the vehicle is increased, whereas the deceleration of the vehicle is increased. When is relatively large, the input torque is quickly brought close to the required input torque by setting the absolute value of the predetermined rate when it becomes a negative value in the return control after the upshift to a relatively large value.

Further, according to the third invention, in a control device of a hybrid vehicle having an electric speed change mechanism and a mechanical speed change mechanism in series, an input torque is obtained after an upshift in a power-off state of the mechanical speed change mechanism. It is possible to suppress a situation in which the input torque cannot return to the required input torque within a predetermined time while returning the power to the required input torque as slowly as possible.

Further, according to the fourth invention, the required input torque after the upshift in the power-off state of the mechanical transmission mechanism is increased to the negative side as the deceleration of the vehicle is increased, whereas the reduction of the vehicle is made. When the speed is relatively high, the input torque is quickly brought close to the required input torque by setting the absolute value of the predetermined rate when it becomes a negative value in the return control after the upshift to a relatively large value.

Further, according to the fifth invention, the higher the temperature of the hydraulic oil that operates the hydraulic engagement device forming the gear stage of the automatic transmission, the smaller the drag in the automatic transmission is likely to be. The higher the temperature of the hydraulic oil, the larger the absolute value of the predetermined rate when it becomes a negative value in the return control after the upshift is set to a large value, so even if the drag in the automatic transmission is small, the input torque will be high. It is easy to approach the required input torque.

Further, according to the sixth invention, the larger the input torque to the automatic transmission is, the larger the deviation from the required input torque is likely to be. However, the automatic return control after the upshift is started. The larger the input torque to the transmission, the larger the absolute value of the predetermined rate when it becomes a negative value in the return control is set to a large value, so even if the deviation of the input torque from the required input torque is large, the input is input. The torque is easily brought closer to the required input torque.

Further, according to the seventh invention, when the deceleration of the vehicle is calculated based on the vehicle speed, the calculation accuracy of the deceleration of the vehicle is also calculated in the extremely low vehicle speed region where the detection accuracy of the vehicle speed itself is deteriorated. On the other hand, in the setting of the predetermined rate according to the deceleration of the vehicle, the change range of the predetermined rate becomes smaller as the vehicle speed is lower, so that the predetermined rate is set in the extremely low vehicle speed region. The change width of is reduced. As a result, it is less likely to be affected by the calculation accuracy of the deceleration of the vehicle in setting the predetermined rate in the return control after the upshift.

It is a figure explaining the schematic structure of the drive device for a vehicle provided in the vehicle to which this invention is applied, and is also a figure explaining the main part of the control function and the control system for various control in a vehicle. FIG. 3 is an operation chart illustrating the relationship between the shift operation of the mechanical stepped speed change unit exemplified in FIG. 1 and the operation of the engagement device used thereof. It is a collinear diagram which shows the relative relationship of the rotation speed of each rotating element in an electric type continuously variable transmission part and a mechanical type stepped speed change part. It is a figure explaining an example of the gear stage allocation table which assigned a plurality of simulated gear stages to a plurality of AT gear stages. It is a figure exemplifying the AT gear stage of a stepped transmission part and the simulated gear stage of a compound transmission on the same collinear diagram as FIG. It is a figure explaining an example of the simulated gear gear shift map used for the shift control of a plurality of simulated gear gears. It is a figure which shows an example of the rotation speed FB control and torque return control at the time of power-off-up shift of a stepped transmission part. After the power-off upshift of the key part of the control operation of the electronic control device, that is, the stepped transmission part, the AT input torque may return to the base torque within a predetermined time while returning the AT input torque to the base torque as gently as possible. It is a flowchart explaining the control operation for suppressing the situation which becomes impossible. It is a figure which shows an example of the time chart when the control operation shown in the flowchart of FIG. 8 is executed.

In the embodiment of the present invention, the rotating member (for example, the above-mentioned engine, the first rotating machine, the second rotating machine, each rotating element of the differential mechanism, the output rotating member of the electric transmission mechanism, and the input rotating member of the automatic transmission). As the value representing the rotation state of (such as), for example, the rotation speed N of the rotating member, the change speed dN / dt of the rotation speed N, and the like. The rotation speed N of the rotating member corresponds to the angular velocity of the rotating member. The change speed dN / dt of the rotation speed N is the time change rate of the rotation speed N, that is, the time derivative, and corresponds to the angular acceleration of the rotating member. The change speed dN / dt of the rotation speed N may be referred to as the rotation change rate dN / dt. In the mathematical formula, the change speed dN / dt of the rotation speed N may be represented by a dot of N.

Further, the speed change ratio in a transmission such as the automatic transmission, a compound transmission in which the electric transmission mechanism and the mechanical transmission mechanism arranged in series are combined is "rotational speed of the rotating member on the input side /. It is the rotation speed of the rotating member on the output side. The high side in this gear ratio is the high vehicle speed side on which the gear ratio becomes smaller. The low side in the gear ratio is the low vehicle speed side on which the gear ratio becomes large. For example, the lowest gear ratio is the gear ratio on the lowest vehicle speed side, which is the lowest vehicle speed side, and is the maximum gear ratio at which the gear ratio is the largest.

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 a vehicle drive device 12 provided in a vehicle 10 to which the present invention is applied, and is a diagram illustrating a main part of a control system for various controls in the vehicle 10. be. In FIG. 1, the vehicle drive device 12 is an electric continuously variable transmission arranged in series on a common axis in an engine 14 functioning as a power source and a transmission case 16 as a non-rotating member attached to a vehicle body. It is provided with a speed change unit 18 and a mechanical stepped speed change unit 20 and the like. The electric continuously variable transmission 18 is directly or indirectly connected to the engine 14 via a damper or the like (not shown). The mechanical stepped speed change unit 20 is connected to the output side of the electric type stepless speed change unit 18. Further, the vehicle drive device 12 includes a differential gear device 24 connected to an output shaft 22 which is an output rotating member of the mechanical stepped speed change unit 20, a pair of axles 26 connected to the differential gear device 24, and the like. I have. In the vehicle drive device 12, the power output from the engine 14 and the second rotary machine MG2, which will be described later, is transmitted to the mechanical stepped speed change unit 20, and the mechanical stepped speed change unit 20 sends the differential gear device 24 and the like. It is transmitted to the drive wheel 28 included in the vehicle 10 via the vehicle 10. The vehicle drive device 12 is suitably used for, for example, an FR (= front engine / rear drive) type vehicle that is vertically placed in the vehicle 10. Hereinafter, the transmission case 16 is referred to as a case 16, the electric continuously variable transmission unit 18 is referred to as a continuously variable transmission unit 18, and the mechanical stepped transmission unit 20 is referred to as a stepped transmission unit 20. Further, as for power, torque and force are also the same unless otherwise specified. Further, the stepless speed change unit 18, the stepped speed change unit 20, and the like are configured substantially symmetrically with respect to the common axis, and the lower half of the axis is omitted in FIG. The common axis is the axis of the crank shaft of the engine 14, the connecting shaft 34 described later, and the like.

The engine 14 is a power source for traveling the vehicle 10, and is a known internal combustion engine such as a gasoline engine or a diesel engine. In this engine 14, the engine torque Te, which is the output torque of the engine 14, is generated by controlling the engine control device 50 such as the throttle actuator, the fuel injection device, and the ignition device provided in the vehicle 10 by the electronic control device 80 described later. Be controlled. In this embodiment, the engine 14 is connected to the continuously variable transmission unit 18 without a fluid transmission device such as a torque converter or a fluid coupling.

The continuously variable transmission unit 18 is a power splitting mechanism that mechanically divides the power of the first rotary machine MG1 and the engine 14 into the first rotary machine MG1 and the intermediate transmission member 30 which is an output rotating member of the continuously variable transmission unit 18. The differential mechanism 32 of the above is provided. The second rotary machine MG2 is connected to the intermediate transmission member 30 so as to be able to transmit power. The continuously variable transmission 18 is an electric continuously variable transmission in which the differential state of the differential mechanism 32 is controlled by controlling the operating state of the first rotary machine MG1. The first rotary machine MG1 is a rotary machine capable of controlling the engine rotation speed Ne, which is the rotation speed of the engine 14, and corresponds to a differential rotary machine, and the second rotary machine MG2 functions as a power source. It is a rotary machine for driving, and corresponds to a rotary machine for traveling drive. The vehicle 10 is a hybrid vehicle equipped with an engine 14 and a second rotary machine MG2 as a power source for traveling. It should be noted that controlling the operating state of the first rotating machine MG1 is to control the operation of the first rotating machine MG1.

The first rotary machine MG1 and the second rotary machine MG2 are rotary electric machines having a function as an electric motor (motor) and a function as a generator (generator), and are so-called motor generators. The first rotary machine MG1 and the second rotary machine MG2 are each connected to a battery 54 as a power storage device provided in the vehicle 10 via an inverter 52 provided in the vehicle 10, and are electronic control devices described later. By controlling the inverter 52 by the 80, the MG1 torque Tg and the MG2 torque Tm, which are the output torques of the first rotary machine MG1 and the second rotary machine MG2, are controlled. The output torque of the rotating machine is the power running torque in the positive torque on the acceleration side and the regenerative torque in the negative torque on the deceleration side. The battery 54 is a power storage device that transfers electric power to each of the first rotating machine MG1 and the second rotating machine MG2.

The differential mechanism 32 is composed of a single pinion type planetary gear device, and includes a sun gear S0, a carrier CA0, and a ring gear R0. The engine 14 is connected to the carrier CA0 so as to be able to transmit power via the connecting shaft 34, the first rotating machine MG1 is connected to the sun gear S0 so that power can be transmitted, and the second rotating machine MG2 can be transmitted to the ring gear R0. Is linked to. In the differential mechanism 32, the carrier CA0 functions as an input element, the sun gear S0 functions as a reaction force element, and the ring gear R0 functions as an output element.

The stepped transmission unit 20 includes a mechanical transmission mechanism as a stepped transmission that constitutes a part of a power transmission path between the intermediate transmission member 30 and the drive wheels 28, that is, the stepless transmission unit 18 and the drive wheels 28. It is a mechanical transmission mechanism that constitutes a part of the power transmission path between the two. The intermediate transmission member 30 also functions as an input rotation member of the stepped speed change unit 20. Since the second rotary machine MG2 is connected to the intermediate transmission member 30 so as to rotate integrally, or because the engine 14 is connected to the input side of the continuously variable transmission unit 18, the stepped speed change unit 20 is connected. , A transmission that constitutes part of the power transmission path between the power source (second rotary machine MG2 or engine 14) and the drive wheels 28. The intermediate transmission member 30 is a transmission member for transmitting the power of the power source to the drive wheels 28. The stepped transmission unit 20 includes, for example, a plurality of sets of planetary gear devices of the first planetary gear device 36 and the second planetary gear device 38, and a plurality of clutches C1, clutches C2, brakes B1 and brakes B2 including a one-way clutch F1. It is a known planetary gear type automatic transmission equipped with an engaging device. Hereinafter, the clutch C1, the clutch C2, the brake B1, and the brake B2 are simply referred to as an engaging device CB unless otherwise specified.

The engagement device CB is a hydraulic friction engagement device composed of a multi-plate or single-plate clutch or brake pressed by a hydraulic actuator, a band brake tightened by the hydraulic actuator, or the like. The engaging device CB is provided by each engaging hydraulic pressure PRcb as each engaging pressure of the pressure-adjusted engaging device CB output from the solenoid valves SL1-SL4 and the like in the hydraulic control circuit 56 provided in the vehicle 10. By changing the engagement torque Tcb, which is each torque capacity, the operating state, which is a state such as engagement or disengagement, can be switched. In order to transmit the AT input torque Ti, which is the input torque input to the stepped transmission unit 20, for example, the AT input torque between the intermediate transmission member 30 and the output shaft 22 without slipping the engaging device CB. An engagement torque Tcb is required to obtain the shared torque of the engagement device CB, which is the transmission torque that needs to be handled by each of the engagement device CB with respect to Ti. However, in the engagement torque Tcb from which the transmission torque is obtained, the transmission torque does not increase even if the engagement torque Tcb is increased. That is, the engagement torque Tcb corresponds to the maximum torque that can be transmitted by the engagement device CB, and the transmission torque corresponds to the torque that the engagement device CB actually transmits. It should be noted that not sliding the engaging device CB does not cause a difference rotation speed in the engaging device CB. Further, the engaging torque Tcb (or transmission torque) and the engaging hydraulic pressure PRcb are in a substantially proportional relationship except for a region for supplying the engaging hydraulic pressure PRcb required for packing the engaging device CB, for example.

In the stepped transmission unit 20, each rotating element of the first planetary gear device 36 and the second planetary gear device 38 is partially connected to each other directly or indirectly via the engaging device CB or the one-way clutch F1. It is connected to the intermediate transmission member 30, the case 16, or the output shaft 22. Each rotating element of the first planetary gear device 36 is a sun gear S1, a carrier CA1, and a ring gear R1, and each rotating element of the second planetary gear device 38 is a sun gear S2, a carrier CA2, and a ring gear R2.

The stepped speed change unit 20 has a gear ratio (also referred to as a gear ratio) γat (= AT input rotation speed Ni) due to engagement of, for example, a predetermined engagement device, which is one of a plurality of engagement devices. / A stepped transmission in which any one of a plurality of gears (also referred to as gears) having different output rotation speeds (No) is formed. That is, in the stepped speed change unit 20, the gear stage is switched, that is, the speed change is executed by engaging any one of the plurality of engaging devices. The stepped transmission unit 20 is a stepped automatic transmission in which each of a plurality of gear stages is formed. In this embodiment, the gear stage formed by the stepped transmission unit 20 is referred to as an AT gear stage. The AT input rotation speed Ni is the input rotation speed of the stepped speed change unit 20, which is the rotation speed of the input rotation member of the stepped speed change unit 20, and has the same value as the rotation speed of the intermediate transmission member 30. It is the same value as the MG2 rotation speed Nm, which is the rotation speed of the rotary machine MG2. The AT input rotation speed Ni can be expressed by the MG2 rotation speed Nm. The output rotation speed No is the rotation speed of the output shaft 22 which is the output rotation speed of the stepped speed change unit 20, and is a compound speed change which is an entire transmission in which the stepless speed change unit 18 and the stepped speed change unit 20 are combined. It is also the output rotation speed of the machine 40. The compound transmission 40 is a transmission that constitutes a part of a power transmission path between the engine 14 and the drive wheels 28.

As shown in the engagement operation table of FIG. 2, for example, the stepped transmission unit 20 has AT 1st gear (“1st” in the figure) -AT 4th gear (“4th” in the figure) as a plurality of AT gears. ”) 4 stages of forward AT gear stages are formed. The gear ratio γat of the AT 1st gear is the largest, and the gear ratio γat becomes smaller as the AT gear on the higher side. The engagement operation table of FIG. 2 summarizes the relationship between each AT gear stage and each operation state of the plurality of engagement devices. That is, the engagement operation table of FIG. 2 summarizes the relationship between each AT gear stage and a predetermined engagement device which is an engagement device that is engaged with each AT gear stage. In FIG. 2, “◯” indicates engagement, “Δ” indicates engagement during engine braking or coast downshift of the stepped transmission unit 20, and blank indicates release. Since the one-way clutch F1 is provided in parallel with the brake B2 that establishes the AT1 speed gear stage, it is not necessary to engage the brake B2 at the time of starting or accelerating. The coast downshift of the stepped speed change unit 20 is, for example, a downshift determined during deceleration running due to accelerator off when the accelerator opening degree θacc is zero or substantially zero. When all of the plurality of engaging devices are released, the stepped transmission unit 20 is in a neutral state in which no AT gear stage is formed, that is, in a neutral state in which power transmission is cut off. Since the one-way clutch F1 is a clutch whose operating state is automatically switched, the stepped transmission unit 20 is set to the neutral state when any of the engaging devices CB is released. Further, to determine the downshift is that the downshift is required.

The stepped speed change unit 20 is released from a predetermined engagement device that forms an AT gear stage before shifting according to an accelerator operation of a driver (that is, a driver), a vehicle speed V, or the like by an electronic control device 80 described later. By controlling the release of the side engaging device and the engagement of the engaging side engaging device among the predetermined engaging devices forming the AT gear stage after shifting, the formed AT gear stage is switched. That is, a plurality of AT gear stages are selectively formed. That is, in the shift control of the stepped speed change unit 20, for example, the shift is executed by gripping any one of the engagement device CB, that is, the shift is executed by switching between the engagement and the disengagement of the engagement device CB. , So-called clutch-to-clutch shift is executed. For example, in the downshift from the AT2 speed gear stage to the AT1 speed gear stage, as shown in the engagement operation table of FIG. 2, the brake B1 serving as the release side engagement device is released and the engagement side engagement device is released. Brake B2 is engaged. At this time, the release transient hydraulic pressure of the brake B1 and the engagement transient hydraulic pressure of the brake B2 are pressure-adjusted and controlled. The release side engagement device is an engagement device involved in the shift of the stepped speed change unit 20 in the engagement device CB, and is an engagement device controlled toward release in the shift transition of the stepped speed change unit 20. Is. The engaging side engaging device is an engaging device involved in shifting of the stepped speed change unit 20 in the engaging device CB, and is controlled toward engagement in the shift transition of the stepped speed change unit 20. It is a combination device. The 2 → 1 downshift can also be executed by automatically engaging the one-way clutch F1 by releasing the brake B1 as the release side engaging device involved in the 2 → 1 downshift. In this embodiment, for example, a downshift from the AT 2nd gear to the AT 1st gear is referred to as a 2 → 1 downshift. The same applies to other upshifts and downshifts.

FIG. 3 is a collinear diagram showing the relative relationship between the rotation speeds of the rotating elements in the stepless speed change unit 18 and the stepped speed change unit 20. In FIG. 3, the three vertical lines Y1, Y2, and Y3 corresponding to the three rotating elements of the differential mechanism 32 constituting the stepless speed change unit 18 are the sun gear S0 corresponding to the second rotating element RE2 in order from the left side. The g-axis representing the rotation speed, the e-axis representing the rotation speed of the carrier CA0 corresponding to the first rotation element RE1, and the rotation speed of the ring gear R0 corresponding to the third rotation element RE3 (that is, the stepped speed change unit 20). It is an m-axis representing an input rotation speed). Further, the four vertical lines Y4, Y5, Y6, and Y7 of the stepped speed change unit 20 correspond to the rotation speed of the sun gear S2 corresponding to the fourth rotation element RE4 and the rotation speed of the sun gear S2 corresponding to the fifth rotation element RE5 in order from the left. Corresponds to the rotational speed of the connected ring gear R1 and carrier CA2 (that is, the rotational speed of the output shaft 22), the rotational speed of the interconnected carrier CA1 and ring gear R2 corresponding to the sixth rotational element RE6, and the seventh rotational element RE7. It is a shaft which represents the rotation speed of the sun gear S1 to be carried. The distance between the vertical lines Y1, Y2, and Y3 is determined according to the gear ratio (also referred to as the gear ratio) ρ0 of the differential mechanism 32. Further, the distance between the vertical lines Y4, Y5, Y6, and Y7 is determined according to the gear ratios ρ1 and ρ2 of the first and second planetary gear devices 36 and 38. When the distance between the sun gear and the carrier is set to correspond to "1" in the relationship between the vertical axis of the co-line diagram, the gear ratio ρ of the planetary gear device (= the number of teeth of the sun gear Zs /) is between the carrier and the ring gear. The interval corresponds to the number of teeth Zr) of the ring gear.

Expressed using the co-line diagram of FIG. 3, in the differential mechanism 32 of the continuously variable transmission unit 18, the engine 14 (see “ENG” in the figure) is connected to the first rotating element RE1 and the second rotating element is connected. The first rotary machine MG1 (see "MG1" in the figure) is connected to RE2, and the second rotary machine MG2 (see "MG2" in the figure) is connected to the third rotary element RE3 that rotates integrally with the intermediate transmission member 30. The rotation of the engine 14 is transmitted to the stepped speed change unit 20 via the intermediate transmission member 30. In the continuously variable transmission unit 18, the relationship between the rotation speed of the sun gear S0 and the rotation speed of the ring gear R0 is shown by the straight lines L0 and L0R that cross the vertical line Y2.

Further, in the stepped speed change unit 20, the fourth rotation element RE4 is selectively connected to the intermediate transmission member 30 via the clutch C1, the fifth rotation element RE5 is connected to the output shaft 22, and the sixth rotation element RE6 is. It is selectively coupled to the intermediate transmission member 30 via the clutch C2 and selectively coupled to the case 16 via the brake B2, and the seventh rotating element RE7 is selectively coupled to the case 16 via the brake B1. ing. In the stepped speed change unit 20, "1st", "2nd", "3rd" on the output shaft 22 are formed by the straight lines L1, L2, L3, L4, LR crossing the vertical line Y5 by the engagement release control of the engagement device CB. , "4th", "Rev" rotation speeds are shown.

The straight lines L0 and the straight lines L1, L2, L3, and L4 shown by the solid lines in FIG. Shows. In this hybrid travel mode, in the differential mechanism 32, when the reaction force torque, which is the negative torque of the first rotary machine MG1, is input to the sun gear S0 in the forward rotation with respect to the engine torque Te input to the carrier CA0. , The engine direct torque Td (= Te / (1 + ρ0) = − (1 / ρ0) × Tg) which becomes a positive torque in the forward rotation appears in the ring gear R0. Then, according to the required driving force, the total torque of the engine direct torque Td and the MG2 torque Tm is the driving torque in the forward direction of the vehicle 10, and the AT gear stage is one of the AT 1st gear stage and the AT 4th gear stage. Is transmitted to the drive wheels 28 via the stepped speed change unit 20 in which the is formed. At this time, the first rotary machine MG1 functions as a generator that generates negative torque in the forward rotation. The generated power Wg of the first rotating machine MG1 is charged in the battery 54 or consumed by the second rotating machine MG2. The second rotary machine MG2 outputs MG2 torque Tm by using all or a part of the generated power Wg, or by using the power from the battery 54 in addition to the generated power Wg.

Although not shown in FIG. 3, in the collinear diagram in the motor running mode in which the motor running mode in which the engine 14 is stopped and the motor running using the second rotary machine MG2 as a power source is possible, the carrier CA0 is used in the differential mechanism 32. Is set to zero rotation, and MG2 torque Tm, which becomes a positive torque in normal rotation, is input to the ring gear R0. At this time, the first rotary machine MG1 connected to the sun gear S0 is put into a no-load state and is idled by negative rotation. That is, in the motor running mode, the engine 14 is not driven, the engine rotation speed Ne is set to zero, and the MG2 torque Tm is any of the AT 1st gear and the AT 4th gear as the driving torque in the forward direction of the vehicle 10. It is transmitted to the drive wheels 28 via the stepped speed change unit 20 in which the AT gear stage is formed. The MG2 torque Tm here is the power running torque of forward rotation.

The straight line L0R and the straight line LR shown by the broken line in FIG. 3 indicate the relative speed of each rotating element in the reverse running in the motor running mode. In reverse travel in this motor drive mode, MG2 torque Tm, which becomes negative torque due to negative rotation, is input to the ring gear R0, and the MG2 torque Tm is used as the drive torque in the reverse direction of the vehicle 10 to form the AT1 speed gear stage. It is transmitted to the drive wheels 28 via the stepped speed change unit 20. In the vehicle 10, the electronic control device 80, which will be described later, is used to form a forward AT gear stage, for example, an AT 1st gear stage, which is a low-side AT gear stage for forward movement among a plurality of AT gear stages. The reverse MG2 torque Tm, whose positive and negative directions are opposite to those of the MG2 torque Tm, is output from the second rotary machine MG2, so that the reverse traveling can be performed. Here, the forward MG2 torque Tm is a power running torque that is a positive torque for forward rotation, and the MG2 torque Tm for backward rotation is a power running torque that is a negative torque for negative rotation. As described above, in the vehicle 10, the forward traveling is performed by reversing the positive and negative of the MG2 torque Tm by using the forward AT gear stage. To use the forward AT gear stage is to use the same AT gear stage as when traveling forward. Even in the hybrid travel mode, the second rotary machine MG2 can have a negative rotation as in the straight line L0R, so that it is possible to perform reverse travel in the same manner as in the motor travel mode.

In the vehicle drive device 12, the carrier CA0 as the first rotating element RE1 to which the engine 14 is connected so as to be able to transmit power, and the sun gear S0 as the second rotating element RE2 to which the first rotating machine MG1 is connected so as to be able to transmit power. A differential mechanism 32 having three rotating elements with the ring gear R0 as the third rotating element RE3 to which the intermediate transmission member 30 is connected is provided, and the differential mechanism is controlled by controlling the operating state of the first rotating machine MG1. A stepless speed change unit 18 as an electric speed change mechanism in which the differential state of 32 is controlled is configured. The third rotating element RE3 to which the intermediate transmission member 30 is connected is, from a different point of view, the third rotating element RE3 to which the second rotating machine MG2 is connected so as to be able to transmit power. That is, in the vehicle drive device 12, the engine 14 has a differential mechanism 32 connected to the differential mechanism 32 so as to be able to transmit power, and a first rotary machine MG1 connected to the differential mechanism 32 so as to be able to transmit power. The stepless speed change unit 18 in which the differential state of the differential mechanism 32 is controlled by controlling the operating state of the machine MG1 is configured. The continuously variable transmission unit 18 has a ratio of the engine rotation speed Ne, which is the same value as the rotation speed of the connecting shaft 34, which is the input rotation member, to the MG2 rotation speed Nm, which is the rotation speed of the intermediate transmission member 30 which is the output rotation member. It is operated as an electric continuously variable transmission in which the speed change ratio γ0 (= Ne / Nm), which is a value, can be changed.

For example, in the hybrid travel mode, the rotation speed of the first rotary machine MG1 is relative to the rotation speed of the ring gear R0, which is constrained by the rotation of the drive wheels 28 due to the formation of the AT gear stage in the stepped speed change unit 20. When the rotation speed of the sun gear S0 is increased or decreased by controlling the above, the rotation speed of the carrier CA0, that is, the engine rotation speed Ne is increased or decreased. Therefore, in hybrid driving, the engine 14 can be operated at an efficient operating point. That is, the stepped speed change unit 20 in which the AT gear stage is formed and the stepless speed change unit 18 operated as a stepless transmission are combined, and the stepless speed change unit 18 and the stepped speed change unit 20 are arranged in series. A continuously variable transmission can be configured as a whole of the transmission 40.

Alternatively, since the stepless transmission 18 can be changed like a stepped transmission, the stepped transmission 20 on which the AT gear stage is formed and the stepless transmission like a stepped transmission can be changed. With 18, the combined transmission 40 as a whole can be changed like a stepped transmission. That is, in the compound transmission 40, the stepped speed change is performed so as to selectively establish a plurality of gear stages having different gear ratios γt (= Ne / No) representing the value of the ratio of the engine rotation speed Ne to the output rotation speed No. It is possible to control the unit 20 and the stepless speed change unit 18. In this embodiment, the gear stage established by the compound transmission 40 is referred to as a simulated gear stage. The gear ratio γt is a total gear ratio formed by the stepless transmission unit 18 and the stepped transmission unit 20 arranged in series, and is the gear ratio γ0 of the stepless transmission unit 18 and the stepped transmission unit 20. The value is obtained by multiplying the gear ratio γat by (γt = γ0 × γat).

The simulated gear stage is, for example, a combination of each AT gear stage of the stepped speed change unit 20 and a gear ratio γ0 of one or a plurality of types of stepless speed change units 18 for each AT gear stage of the stepped speed change unit 20. Assigned to establish one or more types. For example, FIG. 4 is an example of a gear stage allocation table. In FIG. 4, a simulated 1st gear stage-a simulated 3rd gear stage is established for the AT 1st gear stage, and a simulated 4th gear stage-a simulated 6th gear stage is established for the AT 2nd speed gear stage. It is predetermined that a simulated 7th gear-simulated 9th gear is established for the AT 3rd gear, and a simulated 10th gear is established for the AT 4th gear.

FIG. 5 is a diagram illustrating an AT gear stage of the stepped transmission unit 20 and a simulated gear stage of the compound transmission 40 on the same collinear diagram as that of FIG. In FIG. 5, the solid line illustrates the case where the simulated 4-speed gear stage-simulated 6-speed gear is established when the stepped transmission unit 20 is the AT 2nd speed gear stage. In the compound transmission 40, the continuously variable transmission unit 18 is controlled so as to have an engine rotation speed Ne that realizes a predetermined gear ratio γt with respect to the output rotation speed No, so that different simulated gear stages are used in a certain AT gear stage. Is established. Further, the broken line exemplifies the case where the simulated 7th gear is established when the stepped transmission 20 is the AT 3rd gear. In the compound transmission 40, the simulated gear stage is switched by controlling the continuously variable transmission unit 18 in accordance with the switching of the AT gear stage.

Returning to FIG. 1, the vehicle 10 is equipped with a wheel brake device 58. The wheel brake device 58 is a braking device that applies braking torque by the wheel brake to the wheels. The wheel brake device 58 supplies brake hydraulic pressure to the wheel cylinder provided in the wheel brake in response to, for example, a stepping operation with a brake pedal by the driver. In the wheel brake device 58, a master cylinder hydraulic pressure having a size corresponding to the pedaling force of the brake pedal, which is normally generated from the brake master cylinder, is directly supplied to the wheel cylinder as the brake hydraulic pressure. On the other hand, in the wheel brake device 58, for example, during ABS control, vehicle speed control, etc., the brake hydraulic pressure required for each control is supplied to the wheel cylinder regardless of the pedaling force due to the generation of braking torque by the wheel brake. Will be done. The wheels are a driving wheel 28 and a driven wheel (not shown).

Further, the vehicle 10 includes an electronic control device 80 as a controller including a control device for the vehicle 10 related to control of the engine 14, the continuously variable transmission unit 18, and the stepped speed change unit 20. Therefore, FIG. 1 is a diagram showing an input / output system of the electronic control device 80, and is a functional block diagram illustrating a main part of a control function by the electronic control device 80. The electronic control device 80 includes, for example, a so-called microcomputer provided with a CPU, RAM, ROM, an input / output interface, etc., 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. The electronic control device 80 is separately configured for engine control, shift control, and the like, if necessary.

The electronic control device 80 includes various sensors provided in the vehicle 10 (for example, engine rotation speed sensor 60, MG1 rotation speed sensor 62, MG2 rotation speed sensor 64, output rotation speed sensor 66, accelerator opening sensor 68, throttle valve). Various signals based on the values detected by the opening sensor 70, brake pedal sensor 72, G sensor 74, shift position sensor 76, battery sensor 78, oil temperature sensor 79, etc. (for example, engine rotation speed Ne, first rotary machine MG1) MG1 rotation speed Ng, which is the rotation speed, MG2 rotation speed Nm, which is the AT input rotation speed Ni, output rotation speed No corresponding to the vehicle speed V, and accelerator as the driver's acceleration operation amount indicating the magnitude of the driver's acceleration operation. Opening θacc, throttle valve opening θth, which is the opening of the electronic throttle valve, brake on Bon, which is a signal indicating that the brake pedal for operating the wheel brake is being operated by the driver, and pedaling force of the brake pedal. Corresponding brake operation amount Bra indicating the magnitude of the driver's depression operation of the brake pedal, front and rear G of the vehicle 10, operation position POSsh of the shift lever 59 as a shift operation member provided in the vehicle 10, battery of the battery 54 Temperature THbat, battery charge / discharge current Ibat, battery voltage Vbat, hydraulic oil supplied to the hydraulic actuator of the engaging device CB, that is, hydraulic oil temperature THoil, which is the temperature of the hydraulic oil that operates the engaging device CB, etc.) are supplied respectively. Will be done.

The driver's acceleration operation amount, which represents the magnitude of the driver's acceleration operation, is the accelerator operation amount, which is the operation amount of the accelerator operation member such as the accelerator pedal, and is the output request amount of the driver with respect to the vehicle 10. As the output request amount of the driver, a throttle valve opening degree θth or the like can be used in addition to the accelerator opening degree θacc.

The front-rear G of the vehicle 10 is a value representing the acceleration of the vehicle 10, and is a positive value on the acceleration side of the vehicle 10 in which the vehicle speed V increases in the forward travel, and the vehicle 10 in which the vehicle speed V decreases in the forward travel. It becomes a negative value on the deceleration side of. In the region where the front-rear G of the vehicle 10 is a negative value, the front-rear G of the vehicle 10 is a value representing the deceleration of the vehicle 10, and a large deceleration of the vehicle 10 means that the absolute value of the front-rear G is large. That is. In this embodiment, the deceleration of the vehicle 10 is referred to as a vehicle deceleration Gd.

From the electronic control device 80, various command signals (for example, an engine for controlling the engine 14) are transmitted to each device (for example, engine control device 50, inverter 52, hydraulic control circuit 56, wheel brake device 58, etc.) provided in the vehicle 10. Control command signal Se, rotary machine control command signal Smg for controlling the first rotary machine MG1 and second rotary machine MG2, hydraulic control command signal Sat for controlling the operating state of the engagement device CB, braking by the wheel brake. Brake control command signal Sb, etc. for controlling the torque) is output respectively. This hydraulic pressure control command signal Sat is also a hydraulic pressure control command signal for controlling the shift of the stepped speed change unit 20, for example, each of the engaging hydraulic pressure PRcb supplied to each hydraulic actuator of the engaging device CB. This is a command signal for driving the solenoid valves SL1-SL4 and the like. The electronic control device 80 sets a hydraulic pressure instruction value corresponding to the value of each engagement hydraulic pressure PRcb supplied to each hydraulic actuator in order to obtain the target engagement torque Tcb of the engagement device CB, and the hydraulic pressure instruction value thereof. The drive current or drive voltage according to the above is output to the hydraulic control circuit 56.

The electronic control device 80 calculates the charge state value SOC [%] as a value indicating the charge state of the battery 54 based on, for example, the battery charge / discharge current Ibat and the battery voltage Vbat. Further, the electronic control device 80 calculates the chargeable / dischargeable power Win and Wout that define the usable range of the battery power Pbat, which is the power of the battery 54, based on, for example, the battery temperature THbat and the charge state value SOC of the battery 54. do. The chargeable and dischargeable power Win and Wout are the rechargeable power Win as the input power that defines the limit of the input power of the battery 54 and the dischargeable power Wout as the output power that defines the limit of the output power of the battery 54. be. The chargeable and dischargeable power Win and Wout are reduced as the battery temperature THbat is lower in the low temperature range where the battery temperature THbat is lower than the normal range, and are smaller as the battery temperature THbat is higher in the high temperature range where the battery temperature THbat is higher than the normal range. Will be done. Further, the rechargeable power Win is reduced as the charge state value SOC is higher, for example, in a region where the charge state value SOC is high. Further, the dischargeable power Wout is reduced as the charge state value SOC is lower, for example, in a region where the charge state value SOC is low.

The electronic control device 80 includes an AT shift control means, that is, an AT shift control unit 82, and a hybrid control means, that is, a hybrid control unit 84, in order to realize various controls in the vehicle 10.

The AT shift control unit 82 determines the shift of the stepped shift unit 20 by using, for example, an AT gear gear shift map, which is a relationship that is experimentally or designedly obtained and stored in advance, that is, a predetermined relationship. If necessary, shift control of the stepped speed change unit 20 is executed. In the shift control of the stepped speed change unit 20, the AT shift control unit 82 uses the solenoid valves SL1-SL4 to release the engagement of the engagement device CB so as to automatically switch the AT gear stage of the stepped speed change unit 20. The hydraulic pressure control command signal Sat for switching is output to the hydraulic pressure control circuit 56. The AT gear shift map has, for example, a predetermined relationship having a shift line for determining the shift of the stepped shift unit 20 on two-dimensional coordinates with the output rotation speed No and the accelerator opening θacc as variables. .. Here, the vehicle speed V or the like may be used instead of the output rotation speed No, or the required drive torque Tdem, the throttle valve opening degree θth, or the like may be used instead of the accelerator opening degree θacc. Each shift line in the AT gear shift map is an upshift line for determining an upshift and a downshift line for determining a downshift. For each of these shift lines, whether or not the output rotation speed No crosses the line on the line indicating a certain accelerator opening θacc, or whether or not the accelerator opening θacc crosses the line on the line indicating a certain output rotation speed No. That is, it is for determining whether or not the gear has crossed the shift point, which is the value at which the shift on the shift line should be executed, and is predetermined as a series of the shift points.

The hybrid control unit 84 functions as an engine control means for controlling the operation of the engine 14, that is, an engine control unit, and a rotary machine control means for controlling the operation of the first rotary machine MG1 and the second rotary machine MG2 via the inverter 52. That is, it includes a function as a rotary machine control unit, and the engine 14, the first rotary machine MG1, and the second rotary machine MG2 execute hybrid drive control and the like by these control functions. The hybrid control unit 84 calculates the required drive power Pdem by applying the accelerator opening degree θacc and the vehicle speed V to, for example, a drive force map having a predetermined relationship. This required drive power Pdem is, in other words, the required drive torque Tdem at the vehicle speed V at that time. The hybrid control unit 84 considers the charge / dischargeable power Win, Wout, etc. of the battery 54, and considers the engine control command signal Se, which is a command signal for controlling the engine 14 so as to realize the required drive power Pdem, and the first engine control command signal Se. The rotary machine control command signal Smg, which is a command signal for controlling the rotary machine MG1 and the second rotary machine MG2, is output. The engine control command signal Se is, for example, a command value of the engine power Pe, which is the power of the engine 14 that outputs the engine torque Te at the engine rotation speed Ne at that time. The rotary machine control command signal Smg is, for example, a command value of the generated power Wg of the first rotary machine MG1 that outputs the MG1 torque Tg at the MG1 rotation speed Ng at the time of command output as the reaction torque of the engine torque Te. It is a command value of the power consumption Wm of the second rotary machine MG2 that outputs the MG2 torque Tm at the MG2 rotation speed Nm at the time of command output.

When the hybrid control unit 84 operates, for example, the continuously variable transmission 18 as a continuously variable transmission and operates the compound transmission 40 as a whole as a continuously variable transmission, the required drive power Pdem takes into consideration the optimum fuel efficiency of the engine and the like. By controlling the engine 14 and controlling the generated power Wg of the first continuously variable transmission MG1 so that the engine rotation speed Ne and the engine torque Te are obtained so that the engine power Pe that realizes the above can be obtained, there is no stepless speed change unit 18. The step shift control is executed to change the shift ratio γ0 of the continuously variable transmission unit 18. As a result of this control, the gear ratio γt of the compound transmission 40 when operated as a continuously variable transmission is controlled.

When the hybrid control unit 84 shifts the stepless transmission unit 18 like a stepped transmission and shifts the composite transmission 40 as a whole like a stepped transmission, the hybrid control unit 84 has a predetermined relationship, for example, a simulated gear. The speed change determination of the compound transmission 40 is performed using the speed change map, and a plurality of simulated gear stages are selectively established in cooperation with the shift control of the AT gear stage of the stepped speed change unit 20 by the AT shift control unit 82. The shift control of the stepless transmission unit 18 is executed as described above. The plurality of simulated gear stages can be established by controlling the engine rotation speed Ne by the first rotary machine MG1 according to the output rotation speed No so that the respective gear ratios γt can be maintained. The gear ratio γt of each simulated gear stage does not necessarily have to be a constant value over the entire range of the output rotation speed No, and may be changed in a predetermined region, and is limited by the upper limit or the lower limit of the rotation speed of each part. May be added. In this way, the hybrid control unit 84 can perform shift control that changes the engine rotation speed Ne like a stepped shift.

Similar to the AT gear shift map, the simulated gear shift map is predetermined with the output rotation speed No and the accelerator opening θacc as parameters. FIG. 6 is an example of a simulated gear shift map, in which the solid line is an upshift line and the broken line is a downshift line. By switching the simulated gear according to the simulated gear shift map, the combined transmission 40 in which the continuously variable transmission 18 and the stepped transmission 20 are arranged in series has the same shift feeling as that of the stepped transmission. can get. In the simulated stepped speed change control in which the compound transmission 40 as a whole shifts like a stepped transmission, for example, when a driving mode that emphasizes driving performance such as a sports driving mode is selected by the driver, or the required drive torque Tdem is relatively high. If it is large, the combined transmission 40 as a whole may be executed in preference to the continuously variable transmission controlled to operate as a continuously variable transmission, but basically the simulated stepped transmission control is executed except when a predetermined execution is restricted. May be done.

The simulated stepped speed change control by the hybrid control unit 84 and the shift control of the stepped speed change unit 20 by the AT shift control unit 82 are executed in cooperation with each other. In this embodiment, 10 types of simulated gear stages of simulated 1st gear stage-simulated 10th gear stage are assigned to 4 types of AT gear stages of AT 1st speed gear stage-AT 4th speed gear stage. Therefore, the AT gear shift map is defined so that the AT gear shift is performed at the same timing as the shift timing of the simulated gear gear. Specifically, the upshift lines of the simulated gear stages "3 → 4", "6 → 7", and "9 → 10" in FIG. 6 are the AT gear stage shift maps "1 → 2" and "2". It coincides with each upshift line of "→ 3" and "3 → 4" (see "AT1 → 2" etc. described in FIG. 6). Further, the downshift lines of the simulated gear stages "3 ← 4", "6 ← 7", and "9 ← 10" in FIG. 6 are "1 ← 2" and "2 ← 3" of the AT gear stage shift map. , "3 ← 4" coincides with each downshift line (see "AT1 ← 2" etc. described in FIG. 6). Alternatively, the shift command of the AT gear stage may be output to the AT shift control unit 82 based on the shift determination of the simulated gear stage based on the simulated gear shift map of FIG. As described above, when the stepped transmission unit 20 is upshifted, the entire compound transmission 40 is upshifted, while when the stepped transmission unit 20 is downshifted, the entire compound transmission 40 is downshifted. Will be. The AT shift control unit 82 switches the AT gear stage of the stepped speed change unit 20 when the simulated gear stage is switched. Since the AT gear stage is changed at the same timing as the simulated gear stage shift timing, the stepped speed change unit 20 is changed with a change in the engine rotation speed Ne, and the stepped speed change unit 20 is changed. Even if there is a shock due to shifting, it is difficult to give the driver a sense of discomfort.

The hybrid control unit 84 selectively establishes the motor traveling mode or the hybrid traveling mode as the traveling mode according to the traveling state. For example, when the required drive power Pdem is in the motor running region smaller than the predetermined threshold value, the hybrid control unit 84 establishes the motor running mode, while the required drive power Pdem is equal to or higher than the predetermined threshold value. When it is in the hybrid driving region, the hybrid driving mode is established. Further, the hybrid control unit 84 sets the hybrid drive mode when the charge state value SOC of the battery 54 is less than the predetermined engine start threshold value even when the required drive power Pdem is in the motor drive region. To be established. The motor running mode is a running state in which the engine 14 is stopped and the second rotating machine MG2 generates a driving torque to run the motor. The hybrid traveling mode is a traveling state in which the engine 14 is driven. The engine start threshold value is a predetermined threshold value for determining that the charge state value SOC needs to forcibly start the engine 14 to charge the battery 54.

Here, the simulated stepped speed change control of the compound transmission 40 when the stepped speed change unit 20 is accompanied by a shift will be described in detail. The hybrid control unit 84 has a target value setting means, that is, a target value setting unit 86, and a feedback control means, that is, feedback control, in order to realize simulated stepped speed change control of the compound transmission 40 when the stepped speed change unit 20 is accompanied by a shift. It includes a return control means, that is, a return control unit 90, and a rate setting means, that is, a rate setting unit 92.

The target value setting unit 86 changes the AT input rotation speed Ni (= MG2 rotation speed Nm) during the inertia phase in the shift transition of the stepped speed change unit 20 when the stepped speed change unit 20 is changed by the AT shift control unit 82. The target value of the MG2 rotation speed change rate dNm / dt, which is the speed, is sequentially set to a value that changes the MG2 rotation speed Nm with a predetermined behavior toward the synchronous rotation speed after shifting of the stepped speed change unit 20. The MG2 rotation change rate dNm / dt is a value representing the rotation state of the input rotation member of the stepped speed change unit 20. Further, when the AT shift control unit 82 shifts the stepped speed change unit 20, the target value setting unit 86 changes the engine speed, which is the change speed of the engine rotation speed Ne, during the inertia phase in the shift transition of the stepped speed change unit 20. The target value of the rate dNe / dt is sequentially set to a value that changes the engine rotation speed Ne in a predetermined manner toward the target rotation speed after shifting of the stepped speed change unit 20. The engine rotation change rate dNe / dt is a value representing the rotation state of the engine 14. As described above, the AT gear shift is performed at the same timing as the shift timing of the simulated gear gear, so that the target rotation speed after the shift of the stepped speed change unit 20 at the engine rotation speed Ne is a compound shift at the engine rotation speed Ne. It is the same as the synchronous rotation speed after the simulated stepped speed change of the machine 40. In this embodiment, the post-shift synchronous rotation speed of the stepped speed change unit 20 at the MG2 rotation speed Nm is referred to as a post-shift synchronous rotation speed Nmsyca (= No × γata). “Γata” is a gear ratio in the AT gear stage after shifting of the stepped transmission unit 20. Further, in this embodiment, the target rotation speed after shifting of the stepped speed change unit 20 at the engine rotation speed Ne is referred to as a post-shift synchronous rotation speed Nesyca (= No × γta). “Γta” is a gear ratio after simulated stepped shifting of the compound transmission 40. Further, in this embodiment, the target value of the MG2 rotation change rate dNm / dt is referred to as the target MG2 rotation change rate dNmtgt, and the target value of the engine rotation change rate dNe / dt is referred to as the target engine rotation change rate dNetgt.

The feedback control unit 88 has MG2 rotation change rate dNm / dt and engine rotation change rate dNe / dt during the inertia phase in the shift transition of the stepped speed change unit 20 when the step speed change unit 20 is changed by the AT shift control unit 82. MG1 torque Tg and MG2 torque Tm by feedback control based on the engine torque Te and the transmission torque transmitted by the stepped speed change unit 20 so that is the respective target value set by the target value setting unit 86. To control. Since the total torque of the engine direct torque Td appearing in the ring gear R0 and the MG2 torque Tm due to the reaction force torque due to the MG1 torque Tg with respect to the engine torque Te is the AT input torque Ti to the stepped transmission unit 20, the MG1 torque Tg is used. Controlling the MG2 torque Tm is synonymous with controlling its AT input torque Ti.

In the shift control of the stepped transmission unit 20, power-on-upshift, which is an upshift in the power-on state, power-on-downshift, which is a downshift in the power-on state, and power-off, which is an upshift in the power-off state. There are various shift patterns (shift modes) such as upshift and power-off downshift, which is a downshift in a power-off state. The shift in the power-on state is, for example, a shift determined by an increase in the accelerator opening degree θacc or a shift determined by an increase in the vehicle speed V while the accelerator is kept on. The shift in the power-off state is, for example, a shift determined by a decrease in the accelerator opening degree θacc or a shift determined by a decrease in the vehicle speed V while the accelerator is maintained. If neither the release side engaging device nor the engaging side engaging device is in a state of generating transmission torque during shifting, the AT input rotation speed Ni (= MG2 rotation speed Nm) is set in the power-on state. While it is increased as a matter of course, the MG2 rotation speed Nm is decreased as a matter of course in the power-off state. Therefore, the MG2 rotation speed Nm cannot be changed toward the synchronous rotation speed Nmsyca after shifting, and in power-on-up shift and power-off-down shift, the engaging side engaging device that forms the AT gear stage after shifting. It is preferable to advance the shift by generating a transmission torque. On the other hand, in power-off upshifts and power-on-downshifts, where the MG2 rotation speed Nm is changed toward the synchronous rotation speed Nmsyca after shifting, the transmission of the release side engaging device that forms the AT gear stage before shifting It is preferable to advance the shift by reducing the torque. Therefore, in the power-on-up shift and the power-off-down shift, the shift progress side engaging device is the engaging side engaging device. On the other hand, in the power-off upshift and the power-on-downshift, the shift progress side engaging device is the release side engaging device. The shift progress side engagement device is an engagement device on the side of the release side engagement device and the engagement side engagement device in the stepped speed change unit 20 that advances the shift, that is, the engagement device that is the main body that advances the shift. be.

Specifically, the feedback control unit 88 uses the predetermined following equation (1) to obtain the respective target values of the MG2 rotation change rate dNm / dt and the engine rotation change rate dNe / dt, and the engine torque Te. And, MG1 torque Tg and MG2 torque Tm are calculated based on the AT transmission torque Tat. The feedback control unit 88 outputs each rotary machine control command signal Smg for obtaining the calculated MG1 torque Tg and MG2 torque Tm to the inverter 52. The following equation (1) is established for each of the g-axis, e-axis, and m-axis (see FIG. 3) in the stepless speed change unit 18, for example, the inertia (= inertia), the rotation speed, and the on-axis. The equation of motion expressed by torque and the stepless speed change unit 18 have two degrees of freedom (that is, two degrees of freedom that when the rotation speed of two axes of each axis is determined, the rotation speed of the remaining one axis is determined). It is an equation derived based on the relational expression between each other defined by being. Therefore, the values a ₁₁ , ..., b ₁₁ , ..., C ₂₂ in each of the 2 × 2 matrices in the following equation (1) are each of the rotating members constituting the continuously variable transmission unit 18. The value is composed of a combination of inertia and the gear ratio ρ0 of the differential mechanism 32.

The target MG2 rotation change rate dNmtgt and the target engine rotation change rate dNetgt are applied to the MG2 rotation change rate dNm / dt and the engine rotation change rate dNe / dt in the equation (1), respectively. In the target value setting unit 86, for example, the speed change of the stepped speed change unit 20 is a shift pattern among various shift patterns so that the MG2 rotation speed Nm and the engine rotation speed Ne in the inertia phase each show desired behavior. The target MG2 rotation speed change rate based on, which AT gear stage the shift is made, which simulated gear stage the shift is made, and what kind of operating state the engine 14 is in. Set dNmtgt and the target engine speed change rate dNetgt. Therefore, it can be said that the feedback control unit 88 controls the AT input torque Ti by feedback control so that the MG2 rotation speed Nm changes in a desired behavior during the inertia phase in the shift transition of the stepped speed change unit 20. .. In this embodiment, this control in the inertia phase by the feedback control unit 88 is referred to as rotation speed feedback control (= rotation speed FB control).

The engine torque Te in the equation (1) is, for example, the engine torque Te at the engine rotation speed Ne at that time when the engine power Pe that realizes the required drive power Pdem is obtained.

The AT transmission torque Tat in the above equation (1) is the sum of the converted values obtained by converting each transmission torque that needs to be handled by each of the engaging devices CB at the time of shifting of the stepped transmission unit 20 on the intermediate transmission member 30. It is a value, that is, a value obtained by converting the transmission torque transmitted by the stepped transmission unit 20 onto the intermediate transmission member 30. Since the formula (1) is a model formula for advancing the shift of the stepped speed change unit 20, in the present embodiment, the AT transmission torque Tat in the equation (1) is mainly used for advancing the shift for convenience. The transmission torque of the gear shifting progress side engaging device is a value converted on the intermediate transmission member 30. In the above equation (1), a feed forward value is given as the value of the transmission torque of the gear shifting traveling side engaging device.

The AT shift control unit 82 differs in, for example, the shift pattern of the stepped shift unit 20 and which AT gear stage the shift is made so as to balance the shift shock and shift time of the stepped shift unit 20. The transmission torque of the gear shifting traveling side engaging device is set based on the base torque Tib according to the required drive power Pdem, using a predetermined relationship for each gear shifting type. The base torque Tib is, for example, a required input torque Tidem obtained by converting the required drive torque Tdem into a value on the intermediate transmission member 30. Since the required input torque Tidem is changed according to the change of the accelerator opening θacc, the value after the required input torque Tidem is smoothed is used as the base torque Tib from the viewpoint of suppressing the fluctuation of the base torque Tib. You may use it.

The feedback control unit 88 ends the rotation speed FB control when the MG2 rotation speed Nm is synchronized with the post-shift synchronous rotation speed Nmsyca during the inertia phase in the shift transition of the stepped speed change unit 20. In the rotation speed FB control by the feedback control unit 88, the AT input torque Ti is controlled so as to have the target MG2 rotation change rate dNmtgt and the target engine rotation change rate dNetgt. Therefore, the AT input torque Ti at the end of the rotation speed FB control is There is a possibility that it deviates from the base torque Tib. Therefore, the AT input torque Ti deviating from the base torque Tib is returned to the base torque Tib after synchronization with the MG2 rotation speed Nm.

When the MG2 rotation speed Nm is synchronized with the synchronous rotation speed Nmsyca after shifting, the return control unit 90 performs a return control that gradually changes the AT input torque Ti toward the base torque Tib at a predetermined rate Rti. By executing this, the AT input torque Ti deviating from the base torque Tib is returned to the base torque Tib. The return control unit 90 controls MG1 torque Tg and MG2 torque Tm so as to return the AT input torque Ti to the base torque Tib. In this embodiment, the return control by the return control unit 90 after the MG2 rotation speed Nm is synchronized with the synchronous rotation speed Nmsyca after the shift, that is, after the shift of the stepped shift unit 20, is also referred to as torque return control. Refer to.

The rate setting unit 92 sets the predetermined rate Rti in the return control by the return control unit 90, for example, which shift pattern the shift of the stepped shift unit 20 immediately before the return control is, and the shift between the AT gear stages. A predetermined rate is set in advance based on whether or not it is. The predetermined rate Rti is, for example, a predetermined rate of change dTi / dt of the AT input torque Ti that achieves both quick recovery within a predetermined time and suppression of shock by returning too quickly. .. This predetermined time is, for example, a predetermined maximum time that can be tolerated as the time required for returning the AT input torque Ti to the base torque Tib. In this embodiment, the fact that the predetermined rate Rti is large and small is the same as the fact that the absolute value of the rate of change dTi / dt of the AT input torque Ti is large and small.

FIG. 7 is a diagram showing an example of rotational speed FB control and torque return control at the time of power-off upshift of the stepped transmission unit 20. In FIG. 7, the time point t1a indicates the time point when the output of the hydraulic control command signal Sat for executing the n → n + 1 upshift of the stepped transmission unit 20 is started. When the shift progresses and the inertia phase is started by the start of the shift output (see time point t2a), the target MG2 rotation change rate dNmtgt is set during the inertia phase (see part A), and the AT input is performed by the rotation speed FB control. Torque Ti is controlled (see part B). When the MG2 rotation speed Nm becomes close to the synchronous rotation speed Nmsyca after the upshift, the change of the MG2 rotation speed Nm is made gradual in order to smoothly perform the power-off upshift of the stepped speed change unit 20 and reduce the synchronous shock. Such a target MG2 rotation speed change rate dNmtgt is set (see part C). When the MG2 rotation speed Nm synchronizes with the synchronous rotation speed Nmsyca after the upshift, the rotation speed FB control is terminated (see time point t3a). After the MG2 rotation speed Nm is synchronized, the AT input torque Ti is controlled by the torque return control, so that the AT input torque Ti deviated from the base torque Tib is returned to the base torque Tib at a predetermined rate Rti. Is changed toward the base torque Tib (see t3a time point-t4a time point, see part D). When the AT input torque Ti is returned to the base torque Tib, the torque return control is terminated (see time point t4a). The target MG2 rotation change rate dNmtgt is set to zero except during the inertia phase, but it is only used for the rotation speed FB control.

As described above, in the feedback control unit 88, during the power-off upshift of the stepped speed change unit 20, the MG2 rotation change rate dNm / dt is the target MG2 rotation change rate dNmtgt during the inertia phase in the shift transition of the stepped speed change unit 20. The AT input torque Ti is controlled by feedback control so as to be.

Further, as shown in the C section of FIG. 7, the target value setting section 86 has an MG2 rotation speed Nm during the inertia phase in the shift transition of the stepped speed change section 20 at the time of power-off-up shift of the stepped speed change unit 20. Compared with the target MG2 rotation speed change rate dNmtgt when is near the synchronous rotation speed Nmsyca after upshifting, and with the target MG2 rotation speed change rate dNmtgt when the MG2 rotation speed Nm is other than near the synchronous rotation speed Nmsyca after upshifting, MG2 Set to a value that reduces the change in rotation speed Nm. The fact that the MG2 rotation speed Nm is near the synchronous rotation speed Nmsyca after the upshift means that, for example, the absolute value of the rotational speed ΔNm (= Nm-Nmsyca) between the MG2 rotational speed Nm and the synchronous rotational speed Nmsyca after the upshift is a predetermined difference. It means that it is within the rotation speed. This predetermined difference rotation speed is, for example, a predetermined threshold value for determining that the MG2 rotation speed Nm has approached the synchronous rotation speed Nmsyca after the upshift.

By the way, when the wheel brake is activated during the power-off upshift of the stepped speed change unit 20, for example, after the rotation speed FB control is completed, the braking torque by the wheel brake is changed to the braking torque by the regeneration control of the second rotary machine MG2. It is preferable to replace it with. Specifically, the hybrid control unit 84 is driven on demand even if the accelerator opening θacc does not fluctuate when the wheel brake is operated after the power-off-up shift of the stepped speed change unit 20 is completed, that is, after the power-off-up shift. Increase the torque Tdem to the negative side. The hybrid control unit 84 outputs a brake control command signal Sb that reduces the braking torque by the wheel brake by the torque obtained by increasing the required drive torque Tdem to the negative side to the wheel brake device 58. When the required drive torque Tdem is increased to the negative side, the base torque Tib is also increased to the negative side. The hybrid control unit 84 outputs a rotary machine control command signal Smg that increases the regenerative torque by the second rotary machine MG2 by the amount of torque that the base torque Tib is increased to the negative side to the inverter 52. When the wheel brake is activated, the vehicle deceleration Gd is larger than when the wheel brake is not activated, and when the wheel brake is activated, the larger the braking torque due to the wheel brake, the larger the vehicle deceleration Gd. The larger the braking torque due to the wheel brake, that is, the larger the vehicle deceleration Gd, the larger the braking torque due to the regenerative control of the second rotary machine MG2, which is replaced with the braking torque due to the wheel brake. Therefore, the base torque Tib after the power-off upshift of the stepped speed change unit 20 has a larger vehicle deceleration Gd so that the vehicle deceleration Gd is realized by the braking torque by the regenerative control of the second rotary machine MG2. It is enlarged to the negative side. Therefore, if the vehicle deceleration Gd is relatively large after the power-off-up shift of the stepped transmission unit 20, the base torque Tib is relatively significantly reduced. In the return control by the return control unit 90, when the vehicle deceleration Gd is relatively large, the AT input torque Ti is changed toward the base torque Tib at a predetermined rate Rti similar to the case where the vehicle deceleration Gd is relatively small. , There is a possibility that the AT input torque Ti cannot return to the base torque Tib within a predetermined time. Further, if the AT input torque Ti does not return to the base torque Tib within a predetermined time and the AT input torque Ti is suddenly returned to the base torque Tib, a shock may occur. The embodiment shown in FIG. 7 is an example when the wheel brake is in the non-operating state and the vehicle deceleration Gd is relatively small, and the base torque Tib is substantially reduced even after the rotation speed FB control is completed. However, even if the AT input torque Ti is gradually changed toward the base torque Tib, the AT input torque Ti is restored within a predetermined time.

When the return control is executed by uniformly using a predetermined rate Rti that gradually changes the AT input torque Ti toward the base torque Tib after the power-off upshift of the stepped speed change unit 20 regardless of the vehicle deceleration Gd. When the vehicle deceleration Gd is relatively large, it is difficult for the AT input torque Ti to return to the base torque Tib within a predetermined time. On the other hand, if the predetermined rate Rti is set to a large value such that the AT input torque Ti is rapidly changed toward the base torque Tib, the AT input torque Ti is within the predetermined time even when the vehicle deceleration Gd is relatively large. It is easy to return to the base torque Tib. However, since it is sufficient that the AT input torque Ti is returned to the base torque Tib within a predetermined time, it is necessary to uniformly use the predetermined rate Rti set to a large value regardless of the vehicle deceleration Gd to execute the return control. not. After the power-off upshift of the stepped transmission unit 20, the AT input torque Ti cannot return to the base torque Tib within a predetermined time while returning the AT input torque Ti toward the base torque Tib as gently as possible. It is desirable to suppress.

The electronic control device 80 has a control function of returning the AT input torque Ti toward the base torque Tib as gently as possible while suppressing a situation in which the AT input torque Ti cannot return to the base torque Tib within a predetermined time. Further, a state determination means, that is, a state determination unit 94 is provided in order to realize the above.

The state determination unit 94 determines whether or not the power-off upshift of the stepped transmission unit 20 is in transition based on the hydraulic control command signal Sat or the like. Further, when the state determination unit 94 determines that the power-off-up shift of the stepped transmission unit 20 is in transition, it determines whether or not it is after the start of the inertia phase based on the change in the MG2 rotation speed Nm. judge. Further, when the state determination unit 94 determines that it is after the start of the inertia phase, the MG2 rotation speed is based on whether or not the absolute value of the difference rotation speed ΔNm is within a predetermined synchronization determination threshold. It is determined whether or not Nm is in a state of being synchronized with the synchronous rotation speed Nmsyca after the upshift.

When the state determination unit 94 determines that the inertia phase has started, the rate setting unit 92 acquires the vehicle deceleration Gd based on the front and rear G of the vehicle 10 by the G sensor 74.

When the state determination unit 94 determines that the target value setting unit 86 is after the start of the inertia phase and the MG2 rotation speed Nm is not synchronized with the synchronous rotation speed Nmsyca after the upshift, the target MG2 Set the rotation change rate dNmtgt and the target engine rotation change rate dNetgt. At this time, the target value setting unit 86 has a negative target MG2 rotation change rate dNmtgt so that the change of the MG2 rotation speed Nm becomes gradual when the MG2 rotation speed Nm is near the synchronous rotation speed Nmsyca after the upshift. Is set to a value that gradually approaches zero.

When the state determination unit 94 determines that the MG2 rotation speed Nm is not synchronized with the synchronous rotation speed Nmsyca after the upshift, the feedback control unit 88 determines that the MG2 rotation speed Nm is not synchronized with the MG2 rotation speed change. MG1 torque Tg and MG2 torque Tm are controlled by feedback control so that the rate dNm / dt and the engine speed change rate dNe / dt are the respective target values set by the target value setting unit 86, that is, AT input. Controls the torque Ti.

When the return control unit 90 determines that the MG2 rotation speed Nm is synchronized with the synchronous rotation speed Nmsyca after the upshift by the state determination unit 94, the return control unit 90 uses the AT input torque Ti deviated from the base torque Tib as the base torque. In order to return to Tib, return control is executed in which the AT input torque Ti is gradually changed toward the base torque Tib at a predetermined rate Rti.

The rate setting unit 92 is after the state determination unit 94 determines that the MG2 rotation speed Nm is in synchronization with the synchronous rotation speed Nmsyca after the upshift, that is, after the power-off upshift of the stepped speed change unit 20. When the vehicle deceleration Gd is large, the predetermined rate Rti in the return control by the return control unit 90 is set to a larger value than when the vehicle deceleration Gd is small.

The higher the hydraulic oil temperature THoil, the lower the viscosity of the hydraulic oil, and the smaller the drag in the stepped transmission 20 is likely to be. The smaller the drag in the stepped speed change unit 20, the smaller the negative torque acting on the intermediate transmission member 30. Therefore, the rate setting unit 92 sets the predetermined rate Rti in the return control after the power-off upshift of the stepped transmission unit 20 to a larger value as the hydraulic oil temperature THoil is higher.

The larger the AT input torque Ti, the larger the deviation of the AT input torque Ti from the base torque Ti tends to be. Therefore, the rate setting unit 92 sets the predetermined rate Rti in the return control after the power-off upshift of the stepped transmission unit 20 to a larger value as the AT input torque Ti at the time when the return control is started becomes larger. do.

FIG. 8 shows the AT input torque within a predetermined time while returning the AT input torque Ti toward the base torque Tib as gently as possible after the power-off-up shift of the main part of the control operation of the electronic control device 80, that is, the stepped transmission unit 20. It is a flowchart explaining the control operation for suppressing the situation that Ti cannot return to the base torque Tib, and is repeatedly executed, for example, while the vehicle 10 is running. FIG. 9 is an example of a time chart when the control operation shown in the flowchart of FIG. 8 is executed.

In FIG. 8, first, in step S10 corresponding to the function of the state determination unit 94 (hereinafter, step is omitted), it is determined whether or not the power-off upshift of the stepped transmission unit 20 is in transition. If the judgment of S10 is denied, this routine is terminated. If the determination in S10 is affirmed, it is determined in S20 corresponding to the function of the state determination unit 94 whether or not it is after the start of the inertia phase in the power-off-up shift transient. If the judgment of S20 is denied, this routine is terminated. If the determination in S20 is affirmed, the vehicle deceleration Gd is acquired in S30 corresponding to the function of the rate setting unit 92. Next, in S40 corresponding to the function of the state determination unit 94, it is determined whether or not the MG2 rotation speed Nm is in a state of being synchronized with the synchronous rotation speed Nmsyca after the upshift. If the judgment of S40 is denied, the target MG2 rotation change rate dNmtgt and the target engine rotation change rate dNetgt are realized by the rotation speed feedback control in S50 corresponding to the functions of the target value setting unit 86 and the feedback control unit 88. The AT input torque Ti is controlled so as to be so. At this time, when the MG2 rotation speed Nm is in the vicinity of the synchronous rotation speed Nmsyca after the upshift, the target MG2 rotation speed change rate dNmtgt is gradually approached to zero so that the change of the MG2 rotation speed Nm becomes gradual. On the other hand, if the judgment of S40 is affirmed, in S60 corresponding to the functions of the return control unit 90 and the rate setting unit 92, in order to return the AT input torque Ti deviated from the base torque Tib to the base torque Tib, The AT input torque Ti is changed at a predetermined rate Rti by the torque return control. At this time, the predetermined rate Rti in the torque return control is set to a larger value when the vehicle deceleration Gd is large than when it is small.

FIG. 9 is a diagram showing an example of rotational speed FB control and torque return control at the time of power-off upshift of the stepped transmission unit 20, and the wheel brake is in the operating state as compared with the embodiment shown in FIG. This is an embodiment when the vehicle deceleration Gd is large. In FIG. 9, the time point t1b indicates the time point when the output of the hydraulic control command signal Sat for executing the n → n + 1 upshift of the stepped transmission unit 20 is started. After that, when the inertia phase is started (see the time point t2b), the target MG2 rotation change rate dNmtgt is set during the inertia phase, and the AT input torque Ti is controlled by the rotation speed FB control. When the MG2 rotation speed Nm synchronizes with the synchronous rotation speed Nmsyca after the upshift, the rotation speed FB control is terminated (see time point t3b). When the wheel brake is activated, the braking torque by the wheel brake is replaced with the braking torque by the regenerative control of the second rotary machine MG2 after the end of the rotation speed FB control, that is, after the end of the power-off upshift. Therefore, after synchronization with the MG2 rotation speed Nm, the base torque Tib is reduced so as to increase the regenerative torque of the second rotary machine MG2 (see part A). After synchronization of the MG2 rotation speed Nm, the AT input torque Ti is changed toward the base torque Tib at a predetermined rate Rti by the torque return control (see t3b time point-t4b time point). At this time, as in the comparative example shown by the broken line, when the AT input torque Ti is reduced at a predetermined rate Rti similar to that when the vehicle deceleration Gd shown in the embodiment of FIG. 7 is relatively small, the base torque is reduced by a predetermined time. I can't go back to Tib. In this case, the rate of change dTi / dt of the AT input torque Ti is suddenly changed so as to suddenly reduce the AT input torque Ti toward the base torque Tib, and a shock is generated (see part B). In this embodiment shown by the solid line, since the vehicle deceleration Gd is relatively large, the predetermined rate Rti in the torque return control is set to a larger value than that in the comparative example (see part C). As a result, in this embodiment, the shock as shown in the above B portion is suppressed.

As described above, according to the present embodiment, the AT input torque Ti is used as the base torque after the MG2 rotation speed Nm is synchronized with the synchronous rotation speed Nmsyca after the upshift in the power-off upshift of the stepped speed change unit 20. When the vehicle deceleration Gd is large, the predetermined rate Rti when executing the return control for changing toward Tib is set to a larger value than when the vehicle deceleration Gd is small. Therefore, when the vehicle deceleration Gd is relatively small, AT. The input torque Ti is gradually brought closer to the base torque Tib. Further, when the vehicle deceleration Gd is relatively large, the AT input torque Ti is quickly brought close to the base torque Tib. Therefore, after the power-off upshift of the stepped transmission unit 20, the AT input torque Ti can be returned to the base torque Tib within a predetermined time while returning the AT input torque Ti toward the base torque Tib as gently as possible. It is possible to suppress the situation where it disappears.

Further, according to the present embodiment, the higher the hydraulic oil temperature THoil, the larger the predetermined rate Rti in the return control after the power-off upshift of the stepped transmission unit 20 is set, so that the value in the stepped transmission unit 20 is set to a larger value. Even if the drag is made small, the AT input torque Ti can be easily brought close to the base torque Tib.

Further, according to the present embodiment, the larger the AT input torque Ti at the time when the return control after the power-off upshift of the stepped transmission unit 20 is started, the larger the predetermined rate Rti in the return control is set. Therefore, even if the deviation of the AT input torque Ti from the base torque Tib is large, the AT input torque Ti can be easily brought closer to the base torque Tib.

Although the embodiments of the present invention have been described in detail with reference to the drawings, the present invention is also applicable to other aspects.

For example, in the above-described embodiment, the predetermined rate Rti in the return control after the power-off upshift of the stepped transmission unit 20 is set to a larger value when the vehicle deceleration Gd is large than when it is small. As described above, the larger the braking torque due to the wheel brake, the larger the vehicle deceleration Gd. Further, the larger the braking torque by the wheel brake, the larger the braking torque by the regenerative control of the second rotary machine MG2 after the power-off upshift of the stepped transmission unit 20. Therefore, the predetermined rate Rti in the return control after the power-off upshift of the stepped transmission unit 20 may be set to a larger value as the driver's brake operation amount Bra is larger. Alternatively, the predetermined rate Rti in the return control after the power-off upshift of the stepped transmission unit 20 may be set to a larger value as the regenerative torque by the second rotary machine MG2 is larger.

Further, in the above-described embodiment, the vehicle deceleration Gd is acquired based on the front-rear G of the vehicle 10 by the G sensor 74, but the present invention is not limited to this embodiment. For example, the vehicle deceleration Gd may be acquired by calculating the rate of change of the vehicle speed V or the rate of change of the output rotation speed No. Alternatively, the vehicle deceleration Gd may be acquired by estimating the vehicle deceleration Gd based on the driver's brake operation amount Bra. Alternatively, the vehicle deceleration Gd may be acquired by estimating the vehicle deceleration Gd based on the regenerative torque. Alternatively, the vehicle deceleration Gd may be acquired by estimating the vehicle deceleration Gd based on the road gradient information based on the map data stored in advance or the road gradient information based on the big data acquired by communication. Alternatively, the vehicle deceleration Gd may be acquired by estimating the vehicle deceleration Gd by combining any of a plurality of types of vehicle deceleration Gd acquisition methods as described above.

As described above, when the vehicle deceleration Gd is calculated by calculating the rate of change of the vehicle speed V or the rate of change of the output rotation speed No, the detection accuracy of the vehicle speed V or the output rotation speed No itself is extremely low. In the vehicle speed region, the calculation accuracy of the vehicle deceleration Gd may also be deteriorated. Therefore, in the setting of the predetermined rate Rti in the return control according to the vehicle deceleration Gd, the rate setting unit 92 reduces the change width of the predetermined rate Rti as the vehicle speed V or the output rotation speed No corresponding to the vehicle speed V becomes lower. You may. By doing so, the change width of the predetermined rate Rti is reduced in the extremely low vehicle speed region, and the calculation accuracy of the vehicle deceleration Gd in the setting of the predetermined rate Rti in the return control after the power-off upshift of the stepped transmission unit 20 is performed. It is hard to be affected by.

Further, in the above-described embodiment, in the shift control using the model equation of the equation (1), the MG2 rotation change rate dNm / dt is exemplified as a value representing the rotational state of the input rotating member of the stepped speed change unit 20. Although the engine rotation change rate dNe / dt has been exemplified as a value representing the rotation state of the engine 14, the present invention is not limited to this embodiment. For example, the value representing the rotation state may be a rotation speed or the like. In this case, in the shift control using the model formula of the above formula (1), the rotation speed becomes the target value, so that the feedback control amount is calculated based on the difference between the target value and the actual value of the rotation speed. The AT input torque Ti may be controlled by PI control.

Further, in the above-described embodiment, the present invention has been described by exemplifying the combined transmission 40, but the present invention is not limited to this embodiment. For example, an automatic transmission that is a parallel hybrid vehicle equipped with an engine and a rotary machine and is connected to the drive wheels so as to be able to transmit power and constitutes a part of a power transmission path between the engine and the drive wheels. The present invention can be applied even to a vehicle equipped with the vehicle. Or, in a series hybrid vehicle equipped with an engine, a rotating machine for power generation generated by the power of the engine, and a rotating machine for driving driven by the generated power of the rotating machine and / or the power of a battery. Therefore, the present invention can be applied even to a vehicle provided with an automatic transmission that constitutes a part of a power transmission path between a rotating machine for driving and a driving wheel. Alternatively, the present invention can be applied to a vehicle including an engine that functions as a power source and an automatic transmission that forms a part of a power transmission path between the engine and the drive wheels. Alternatively, the present invention can be applied to a vehicle provided with a rotating machine that functions as a power source and an automatic transmission that constitutes a part of a power transmission path between the rotating machine and the drive wheels. .. In short, the present invention can be applied to any vehicle provided with a power source and an automatic transmission that constitutes a part of a power transmission path between the power source and the drive wheels.

Further, in the above-described embodiment, the vehicle 10 has a differential mechanism 32 which is a single pinion type planetary gear device, and includes a stepless speed change unit 18 which functions as an electric speed change mechanism. Not limited to. For example, the stepless speed change unit 18 may be a speed change mechanism whose differential action can be limited by the control of a clutch or a brake connected to a rotating element of the differential mechanism 32. Further, the differential mechanism 32 may be a double pinion type planetary gear device. Further, the differential mechanism 32 may be a differential mechanism having four or more rotating elements by connecting a plurality of planetary gear devices to each other. Further, even if the differential mechanism 32 is a differential gear device in which a pinion driven to be rotated by an engine 14 and a pair of bevel gears meshing with the pinion are connected to a first rotary machine MG1 and an intermediate transmission member 30, respectively. good. Further, in the differential mechanism 32, in a configuration in which two or more planetary gear devices are interconnected by a part of the rotating elements constituting the planetary gear device, the engine, the rotating machine, and the driving wheel are respectively connected to the rotating elements of the planetary gear device. It may be a mechanism that is connected so that power can be transmitted.

Further, in the above-described embodiment, the stepped transmission unit 20, which is a planetary gear type automatic transmission, is exemplified as an automatic transmission that constitutes a part of the power transmission path between the power source and the drive wheels. The present invention is not limited to this aspect. For example, the automatic transmission includes a synchronous meshing parallel two-axis automatic transmission, a known DCT (Dual Clutch Transmission) which is a synchronous meshing parallel two-axis automatic transmission and has two input shafts, and a belt. It may be an automatic transmission such as a known continuously variable transmission mechanical type continuously variable transmission such as a type continuously variable transmission. When this automatic transmission is a continuously variable transmission, the gear ratio of the continuously variable transmission when shifting like a stepped transmission is a gear stage formed in a pseudo manner like a simulated gear stage. It becomes the gear ratio of.

Further, in the above-described embodiment, an embodiment in which 10 types of simulated gear stages are assigned to 4 types of AT gear stages has been exemplified, but the embodiment is not limited to this mode. Preferably, the number of simulated gear stages may be equal to or greater than the number of AT gear stages, and may be the same as the number of AT gear stages, but it is desirable that the number is larger than the number of AT gear stages, for example, twice. The above is appropriate. The shift of the AT gear stage is performed so that the rotation speed of the intermediate transmission member 30 and the second rotary machine MG2 connected to the intermediate transmission member 30 is maintained within a predetermined rotation speed range, and is simulated. The gear shift is performed so that the engine rotation speed Ne is maintained within a predetermined rotation speed range, and the number of each gear is appropriately determined.

It should be noted that the above is only one embodiment, and the present invention can be carried out in a mode in which various changes and improvements are made based on the knowledge of those skilled in the art.

10: Vehicle (hybrid vehicle)
14: Engine (power source)
18: Electric continuously variable transmission (electric continuously variable transmission mechanism)
20: Mechanical stepped transmission (automatic transmission, mechanical transmission mechanism, stepped transmission)
28: Drive wheel 30: Intermediate transmission member (input rotation member of automatic transmission, output rotation member of electric transmission mechanism)
32: Differential mechanism 80: Electronic control device (control device)
88: Feedback control unit 90: Return control unit 92: Rate setting unit 94: Status determination unit CB: Engagement device MG1: First rotating machine MG2: Second rotating machine (power source, rotating machine)

Claims (7)

A control device for a vehicle including a power source and an automatic transmission that forms part of a power transmission path between the power source and the drive wheels.
At the time of upshifting in the power-off state of the automatic transmission, a value representing the rotational state of the input rotating member of the automatic transmission during the inertia phase in the shifting transition of the automatic transmission determines the rotational speed of the input rotating member. A feedback control unit that controls the input torque to the automatic transmission by feedback control so that the target value is changed toward the synchronous rotation speed after the upshift.
A state determination unit for determining whether or not the rotation speed of the input rotation member of the automatic transmission is synchronized with the synchronous rotation speed after the upshift.
When it is determined that the rotation speed of the input rotation member of the automatic transmission is synchronized with the synchronous rotation speed after the upshift, the input torque to the automatic transmission is predetermined toward the required input torque. A return control unit that executes return control that gradually changes with the rate,
A rate setting unit that sets the absolute value of the predetermined rate when it becomes a negative value in the return control after the upshift to a larger value when the deceleration of the vehicle is large than when it is small. A vehicle control device comprising. The vehicle is equipped with a rotating machine that functions as the power source.
The required input torque after the upshift is increased to the negative side as the deceleration of the vehicle is large so that the deceleration of the vehicle is realized by the braking torque by the regenerative control of the rotating machine. The vehicle control device according to claim 1. The vehicle has an engine that functions as the power source, a differential mechanism to which the engine is connected so as to be able to transmit power, and a first rotary machine that is connected to the differential mechanism so that power can be transmitted. The power is connected to an electric transmission mechanism in which the differential state of the differential mechanism is controlled by controlling the operating state of the rotary machine and an output rotating member of the electric transmission mechanism so as to be able to transmit power. It is a hybrid vehicle equipped with a second rotating machine that functions as a source.
The automatic transmission is a mechanical transmission mechanism that constitutes a part of a power transmission path between the output rotating member of the electric transmission mechanism and the drive wheels and that each of a plurality of gear stages is formed.
At the time of shifting of the mechanical speed change mechanism, the feedback control unit sets a value representing the rotational state of the input rotating member and a value representing the rotational state of the engine as their respective target values in the inertia phase. Based on the output torque of the engine and the transmission torque transmitted by the mechanical transmission mechanism, the output torque of the first rotary machine and the output torque of the second rotary machine are controlled by feedback control.
The return control unit is characterized in that it executes the return control when the rotation speed of the input rotation member of the mechanical speed change mechanism becomes synchronized with the synchronous rotation speed after the shift. The vehicle control device according to 1. The required input torque after the upshift in the power-off state of the mechanical speed change mechanism is the deceleration of the vehicle so that the deceleration of the vehicle is realized by the braking torque by the regenerative control of the second rotary machine. The vehicle control device according to claim 3, wherein the larger the value, the larger the value on the negative side. The automatic transmission is a stepped transmission in which one of a plurality of gear stages is formed by the engagement of any one of the plurality of hydraulic engagement devices.
The rate setting unit sets the absolute value of the predetermined rate when it becomes a negative value in the return control after the upshift to a larger value as the temperature of the hydraulic oil that operates the engaging device increases. The vehicle control device according to any one of claims 1 to 4, characterized in that. The rate setting unit sets the absolute value of the predetermined rate when it becomes a negative value in the return control after the upshift, and the input torque to the automatic transmission at the time when the return control is started. The vehicle control device according to any one of claims 1 to 5, wherein the larger the value is, the larger the value is set. The rate setting unit according to any one of claims 1 to 6, wherein the rate setting unit reduces the change width of the predetermined rate as the vehicle speed decreases in the setting of the predetermined rate according to the deceleration of the vehicle. The vehicle control device described.

Images