JP7272213B2 - Hybrid vehicle control device - Google Patents

Description

The present invention relates to a control device for a hybrid vehicle having an engine with a supercharger, a rotary machine, and a transmission.

A hybrid vehicle is well known that includes (a) an engine that functions as a power source for running, and (b) a rotating machine that is coupled to driving wheels so as to be able to transmit power. For example, the vehicle described in Patent Literature 1 is one of them. This patent document 1 discloses that the engine is controlled so that the rotational speed of the engine is within a range not exceeding the allowable maximum rotational speed in which a margin is secured with respect to the predetermined upper limit rotational speed of the engine. .

JP 2008-247205 A

By the way, in the hybrid vehicle described above, there is a possibility that the rotary machine will be in a high rotation state to the extent that the rotary machine reaches a predetermined upper limit rotation speed. On the other hand, in order to prevent the rotating machine from being in such a high rotation state, the allowable maximum rotating speed that secures a margin for the predetermined upper limit rotating speed of the rotating machine is increased. If it exceeds, it is conceivable to reduce the output torque of the engine. However, when the engine has a supercharger, the response delay of the engine output torque occurs due to the response delay of the supercharging pressure. Also, there is a possibility that the rotation speed of the rotating machine may easily fall into a high rotation state to the extent that the rotation speed reaches the predetermined upper limit rotation speed.

SUMMARY OF THE INVENTION The present invention has been made against the background of the above circumstances, and an object of the present invention is to provide a hybrid vehicle capable of suppressing a rotation speed of a rotating machine from falling into a high rotation state exceeding an allowable maximum rotation speed. to provide a control device for

The gist of the first invention is (a) an engine with a supercharger that functions as a power source for running, a rotating machine that is connected to driving wheels so that power can be transmitted, and the rotating machine and the driving wheels. A control device for a hybrid vehicle comprising: a transmission provided in a power transmission path between When the rotation speed of the rotating machine exceeds the allowable maximum rotation speed for which is secured, the output torque of the engine is reduced so that the rotation speed of the rotating machine does not reach the predetermined upper limit rotation speed. and (c) increasing the rotational speed difference when the rotational speed difference between the allowable maximum rotational speed and the rotational speed of the rotating machine is equal to or less than a set marginal rotational speed difference. (d) based on the supercharging pressure by the supercharger, when the supercharging pressure is high, the margin rotational speed difference is set to a larger value than when the supercharging pressure is low. and a marginal rotational speed difference setting unit .

The gist of the second invention is that in the first invention, (e) the marginal rotational speed difference setting unit sets the marginal rotational speed difference to a larger value as the supercharging pressure is higher. be.

Further, the gist of the third invention is: (a) an engine with a supercharger that functions as a power source for running; a rotating machine that is connected to drive wheels so that power can be transmitted; and a transmission provided in a power transmission path between a wheel and a hybrid vehicle, wherein: When the rotation speed of the rotating machine exceeds the allowable maximum rotation speed for which a margin is secured, the output torque of the engine is reduced so that the rotation speed of the rotating machine does not reach the predetermined upper limit rotation speed. and (c) a rotational speed difference between the maximum permissible rotational speed and the rotational speed of the rotating machine, which increases the rotational speed difference when the rotational speed difference is equal to or less than a set marginal rotational speed difference. (f) a state for determining whether or not the vehicle state is a predetermined vehicle state in which the rotational speed of the rotating machine easily exceeds the maximum allowable rotational speed; (g) the gear ratio changing unit, when it is determined that the vehicle state is the predetermined vehicle state and the rotational speed difference is equal to or less than the marginal rotational speed difference, To change the gear ratio of the transmission so as to increase the speed difference.

Further, the gist of the fourth invention is that in the third invention, (h) the state determination unit determines whether or not the road surface of the hybrid vehicle is in a state where the driving wheels are likely to spin. Based on this, it is determined whether or not the vehicle state is the predetermined vehicle state.

Further, the gist of the fifth invention is that, in the third invention or the fourth invention, (j) the state determination unit causes the rotating machine to generate power so that the rotation speed of the rotating machine does not reach the predetermined upper limit rotation speed; To determine whether or not the vehicle state is the predetermined vehicle state based on whether or not the vehicle is in the receiving state.

According to the control device for a hybrid vehicle of the first aspect of the invention, (b) the rotating machine is rotated at an allowable maximum rotational speed that secures a margin of the rotational speed of the rotating machine with respect to the predetermined upper limit rotational speed of the rotating machine. (c) the allowable maximum rotation speed and the rotation a gear ratio changing unit that changes the gear ratio of the transmission so as to increase the rotational speed difference when the rotational speed difference from the rotational speed of the machine becomes equal to or less than a set marginal rotational speed difference; Prepare. Therefore, when the rotational speed difference becomes equal to or less than the marginal rotational speed difference, the gear ratio of the transmission is changed so as to increase the rotational speed difference. The difference from the rotational speed of the machine is suppressed from becoming equal to or less than the marginal rotational speed difference. As a result, a relatively sufficient margin is secured in the difference between the allowable maximum rotation speed and the rotation speed of the rotating machine, so that the rotation speed of the rotating machine does not fall into a high rotation state exceeding the allowable maximum rotation speed. can be suppressed. (d) an allowance rotation speed difference setting unit for setting the allowance rotation speed difference to a larger value when the boost pressure is high than when the boost pressure is low, based on the boost pressure by the supercharger; Therefore, when the supercharging pressure is high, the rotational speed margin margin is set to a larger value than when the supercharging pressure is low. It becomes difficult to fall below the difference. As a result, when the supercharging pressure is low, it is more difficult to change the gear ratio of the transmission than when it is high. It is possible to prevent the rotation speed of the rotating machine from falling into a high rotation state exceeding the maximum allowable rotation speed.

According to the hybrid vehicle control device of the second aspect of the invention, (e) the marginal rotational speed difference setting unit sets the marginal rotational speed difference to a larger value as the supercharging pressure is higher . As a result, it is possible to more preferably prevent the rotation speed of the rotating machine from falling into a high rotation state exceeding the maximum allowable rotation speed.

According to the hybrid vehicle control device of the third aspect of the invention, (a) an engine with a supercharger functioning as a power source for running; and a transmission provided in a power transmission path between drive wheels, wherein: (b) the rotation speed of the rotating machine is controlled relative to a predetermined upper limit rotation speed of the rotating machine; When the rotation speed of the rotating machine exceeds the allowable maximum rotation speed for which the margin is secured, the output torque of the engine is reduced so that the rotation speed of the rotating machine does not reach the predetermined upper limit rotation speed. and (c) increasing the rotation speed difference when the rotation speed difference between the allowable maximum rotation speed and the rotation speed of the rotating machine is equal to or less than a set allowance rotation speed difference. and (f) determining whether the vehicle state is a predetermined vehicle state in which the rotation speed of the rotating machine easily exceeds the maximum allowable rotation speed. (g) the gear ratio changing unit, when it is determined that the vehicle state is the predetermined vehicle state and the rotational speed difference is equal to or less than the marginal rotational speed difference; The gear ratio of the transmission is changed so as to increase the rotation speed difference. Therefore, the gear ratio changing unit changes the gear ratio of the transmission when it is determined that the vehicle state is the predetermined vehicle state and the rotational speed difference is equal to or less than the marginal rotational speed difference. Therefore, for example, compared to changing the gear ratio of the transmission when the rotational speed difference becomes equal to or less than the marginal rotational speed difference, excessive change of the gear ratio of the transmission should be suppressed. can be done.

According to the hybrid vehicle control device of the fourth aspect of the invention, (h) the state determination unit determines whether or not the road surface of the hybrid vehicle is in a road surface state in which the driving wheels are likely to spin. It is determined whether or not the state is the predetermined vehicle state. Therefore, when the hybrid vehicle is running on a road surface where the drive wheels are likely to spin, it is possible to prevent the rotation speed of the rotating machine from falling into a high rotation state exceeding the maximum allowable rotation speed.

According to the hybrid vehicle control device of the fifth aspect of the invention, (i) the high rotation prevention unit further reduces the rotation speed of the rotating machine when the rotation speed of the rotating machine exceeds the maximum allowable rotation speed. (j) The state determination unit determines whether or not the rotating machine is subject to a predetermined output limitation. Based on this, it is determined whether or not the vehicle state is the predetermined vehicle state. Therefore, when the rotating machine is subject to the predetermined output limitation, it is possible to prevent the rotating machine from falling into a high rotation state in which the rotational speed of the rotating machine exceeds the maximum allowable rotational speed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram for explaining a schematic configuration of a vehicle to which the present invention is applied, and is a diagram for explaining main parts of a control system and control functions for various controls in the vehicle; It is a figure explaining a schematic structure of an engine. FIG. 2 is an operation chart for explaining the relationship between the shift operation of the mechanical stepped transmission illustrated in FIG. 1 and the combination of the operation of the engaging device used therefor; FIG. FIG. 4 is a collinear diagram showing the relative relationship between the rotational speeds of the rotating elements in the continuously variable electric transmission section and the stepped mechanical transmission section; FIG. 5 is a diagram illustrating an example of a gear stage allocation table in which a plurality of simulated gear stages are allocated to a plurality of AT gear stages; FIG. 4 is a diagram for explaining a hydraulic control circuit, and a diagram for explaining a hydraulic source that supplies working oil to the hydraulic control circuit; FIG. 4 is a diagram showing an example of an optimum engine operating point; FIG. 5 is a diagram illustrating an example of a simulated gear shift map used for shift control of a plurality of simulated gear stages; FIG. 4 is a diagram showing an example of a power source switching map used for switching control between motor running and hybrid running. FIG. 4 is a diagram showing an example of a usable region of the engine rotation speed, in the case of AT 1st gear; FIG. 4 is a diagram showing an example of a usable range of engine rotation speeds, in the case of AT 2nd gear; FIG. 4 is a diagram showing an example of a usable region of the engine rotation speed, in the case of AT 3rd gear; FIG. 4 is a diagram showing an example of a usable region of the engine rotation speed, in the case of AT 4th gear; FIG. 5 is a diagram showing an example of a marginal rotational speed difference setting map used for setting marginal rotational speed difference; 4 is a flowchart for explaining a main part of the control operation of the electronic control device, and is a flowchart for explaining the control operation for suppressing the rotation speed of the second rotating machine from falling into a high rotation state exceeding the allowable maximum rotation speed. FIG. 16 is a time chart when an example of the control operation shown in the flowchart of FIG. 15 is executed; FIG. FIG. 2 is a diagram for explaining a schematic configuration of a vehicle to which the present invention is applied, and is a diagram for explaining a vehicle different from the vehicle in FIG. 1;

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

FIG. 1 is a diagram for explaining a schematic configuration of a vehicle 10 to which the present invention is applied, and is a diagram for explaining main parts of a control system for various controls in the vehicle 10. As shown in FIG. In FIG. 1, a vehicle 10 is a hybrid vehicle that includes an engine 12, a first rotating machine MG1, and a second rotating machine (rotating machine) MG2. The vehicle 10 also includes drive wheels 14 and a power transmission device 16 provided in a power transmission path between the engine 12 and the drive wheels 14 . The second rotary machine MG2 is connected to the driving wheels 14 so as to be able to transmit power.

FIG. 2 is a diagram for explaining a schematic configuration of the engine 12. As shown in FIG. In FIG. 2, the engine 12 is a power source for running the vehicle 10, and is a known internal combustion engine such as a gasoline engine or a diesel engine having a supercharger 18, that is, an engine with a supercharger 18. An intake system of the engine 12 is provided with an intake pipe 20, and the intake pipe 20 is connected to an intake manifold 22 attached to the engine body 12a. An exhaust system of the engine 12 is provided with an exhaust pipe 24, and the exhaust pipe 24 is connected to an exhaust manifold 26 attached to the engine body 12a. The supercharger 18 is a known exhaust turbine type supercharger, that is, a turbocharger, having a compressor 18 c provided in the intake pipe 20 and a turbine 18 t provided in the exhaust pipe 24 . The turbine 18t is rotationally driven by the exhaust gas flow. The compressor 18c is connected to the turbine 18t, and is rotationally driven by the turbine 18t to compress intake air to the engine 12, that is, intake air.

The exhaust pipe 24 is provided in parallel with an exhaust bypass 28 for bypassing the turbine 18t from the upstream side of the turbine 18t to the downstream side to flow the exhaust gas. The exhaust bypass 28 is provided with a waste gate valve (=WGV) 30 for continuously controlling the ratio of the exhaust passing through the turbine 18 t and the exhaust passing through the exhaust bypass 28 . The waste gate valve 30 is continuously adjusted in valve opening by operating an actuator (not shown) by an electronic control device (control device) 100, which will be described later. Exhaust gas from the engine 12 is more likely to be discharged through the exhaust bypass 28 as the opening of the wastegate valve 30 increases. Therefore, in a supercharging state of the engine 12 in which the supercharging action of the supercharger 18 is effective, the supercharging pressure Pchg by the supercharger 18 becomes lower as the valve opening of the waste gate valve 30 increases. The supercharging pressure Pchg by the supercharger 18 is the pressure of the intake air, which is the air pressure in the intake pipe 20 downstream of the compressor 18c. The low side of the supercharging pressure Pchg is, for example, the side of the intake pressure in the non-supercharging state of the engine 12 where the supercharging action of the supercharger 18 is not effective at all. It is the side that becomes the pressure of the intake air in an engine that does not.

An air cleaner 32 is provided at the inlet of the intake pipe 20, and an air flow meter 34 for measuring the intake air amount Qair of the engine 12 is provided in the intake pipe 20 downstream from the air cleaner 32 and upstream from the compressor 18c. there is The intake pipe 20 downstream of the compressor 18c is provided with an intercooler 36, which is a heat exchanger that cools the intake air compressed by the supercharger 18 by exchanging heat between the intake air and outside air or cooling water. there is An electronic throttle valve 38 is provided in the intake pipe 20 downstream of the intercooler 36 and upstream of the intake manifold 22. The electronic throttle valve 38 is controlled to open and close by operating a throttle actuator (not shown) by an electronic control unit 100, which will be described later. It is In the intake pipe 20 between the intercooler 36 and the electronic throttle valve 38, there are provided a supercharging pressure sensor 40 for detecting the supercharging pressure Pchg by the supercharger 18, and an intake air temperature sensor for detecting the intake air temperature THair. 42 are provided. A throttle valve opening sensor 44 for detecting a throttle valve opening .theta.th, which is the opening of the electronic throttle valve 38, is provided near the electronic throttle valve 38, for example, at a throttle actuator.

The intake pipe 20 is provided in parallel with an air recirculation bypass 46 for recirculating the air by detouring the compressor 18c from the downstream side to the upstream side of the compressor 18c. The air recirculation bypass 46 is provided with an air bypass valve (=ABV) 48 that is opened when the electronic throttle valve 38 is suddenly closed, for example, to suppress surge generation and protect the compressor 18c. . The valve opening degree of the air bypass valve 48 is continuously adjusted by operating an actuator (not shown) by an electronic control unit 100, which will be described later.

The engine 12 includes an electronic throttle valve 38, a fuel injection device, an ignition device, a waste gate valve 30, an air bypass valve 48, etc., and an engine control device 50 (see FIG. 1) is controlled by an electronic control device 100, which will be described later. The engine torque Te, which is the output torque of the engine 12, is controlled by.

Returning to FIG. 1, the first rotary machine MG1 and the second rotary machine MG2 are rotary electric machines having a function as an electric motor and a function as a generator, and are so-called motor generators. The first rotary machine MG1 and the second rotary machine MG2 can serve as power sources for the vehicle 10 to run. The first rotary machine MG1 and the second rotary machine MG2 are each connected to a battery 54 provided in the vehicle 10 via an inverter 52 provided in the vehicle 10 . The first rotary machine MG1 and the second rotary machine MG2 are controlled by an electronic control unit 100, which will be described later, to control the inverter 52, so that the MG1 torque Tg, which is the output torque of the first rotary machine MG1, and the second rotary machine MG2, respectively. MG2 torque Tm, which is the output torque of , is controlled. For example, in the case of positive rotation, the output torque of the rotating machine is power running torque when the positive torque is on the acceleration side, and regenerative torque when the negative torque is on the deceleration side. The battery 54 is a power storage device that transfers electric power to and from each of the first rotary machine MG1 and the second rotary machine MG2. The first rotary machine MG1 and the second rotary machine MG2 are provided inside a case 56 that is a non-rotating member attached to the vehicle body.

The power transmission device 16 includes an electric continuously variable transmission section 58, a mechanical stepped transmission section 60, etc., which are arranged in series on a common axis within a case 56 as a non-rotating member attached to the vehicle body. ing. The electric continuously variable transmission section 58 is connected to the engine 12 directly or indirectly via a damper (not shown) or the like. The mechanical stepped transmission section 60 is connected to the output side of the electric continuously variable transmission section 58 . That is, the mechanical stepped transmission section 60 is provided in the power transmission path between the second rotary machine MG2 and the drive wheels 14 . The power transmission device 16 also includes a differential gear device 64 connected to an output shaft 62, which is an output rotating member of the mechanical stepped transmission 60, an axle 66 connected to the differential gear device 64, and the like. . In the power transmission device 16, the power output from the engine 12 and the second rotary machine MG2 is transmitted to the mechanical stepped transmission section 60, and from the mechanical stepped transmission section 60 via the differential gear device 64 and the like. It is transmitted to the drive wheels 14 . The power transmission device 16 configured in this manner is preferably used in an FR (front engine, rear drive) type vehicle. Hereinafter, the electric continuously variable transmission portion 58 will be referred to as the continuously variable transmission portion 58, and the mechanical stepped transmission portion 60 will be referred to as the stepped transmission portion 60. In addition, motive power is the same as torque and force unless otherwise specified. Further, the continuously variable transmission section 58, the stepped transmission section 60, etc. are constructed 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 crankshaft of the engine 12, the connecting shaft 68 connected to the crankshaft, and the like.

The continuously variable transmission section 58 serves as a power splitting mechanism that mechanically divides the power of the first rotary machine MG1 and the engine 12 to the first rotary machine MG1 and an intermediate transmission member 70 that is an output rotating member of the continuously variable transmission section 58. and a differential mechanism 72. A second rotary machine MG2 is coupled to the intermediate transmission member 70 so as to be capable of power transmission. The first rotating machine MG1 is a rotating machine to which the power of the engine 12 is transmitted. Since the intermediate transmission member 70 is connected to the driving wheels 14 via the stepped transmission portion 60, the second rotating machine MG2 is a rotating machine connected to the driving wheels 14 so as to be capable of power transmission. The continuously variable transmission unit 58 is an electric continuously variable transmission in which the differential state of the differential mechanism 72 is controlled by controlling the operating state of the first rotary machine MG1. The first rotating machine MG1 is a rotating machine capable of controlling the engine rotation speed Ne, which is the rotation speed of the engine 12, for example, a rotating machine capable of increasing the engine rotation speed Ne. The power transmission device 16 transmits the power of the power source to the drive wheels 14 . Note that controlling the operating state of the first rotating machine MG1 means controlling the operation of the first rotating machine MG1.

The differential mechanism 72 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 12 is connected to the carrier CA0 via a connecting shaft 68 so as to be able to transmit power, the first rotating machine MG1 is connected to be able to transmit power to the sun gear S0, and the second rotating machine MG2 is capable of transmitting power to the ring gear R0. connected to In differential mechanism 72, carrier CA0 functions as an input element, sun gear S0 functions as a reaction element, and ring gear R0 functions as an output element.

The stepped transmission portion 60 is an automatic transmission as a stepped transmission forming part of the power transmission path between the intermediate transmission member 70 and the drive wheels 14 , that is, the stepless transmission portion 58 and the drive wheels 14 . It is a mechanical transmission mechanism that constitutes a part of the power transmission path between. The intermediate transmission member 70 also functions as an input rotating member of the stepped transmission portion 60 . Since the second rotary machine MG2 is connected to the intermediate transmission member 70 so as to rotate integrally, or the engine 12 is connected to the input side of the continuously variable transmission section 58, the stepped transmission section 60 is , a transmission provided in a power transmission path between the power source (the second rotary machine MG2 or the engine 12) and the drive wheels . The intermediate transmission member 70 is a transmission member for transmitting the power of the power source to the driving wheels 14 . The stepped transmission unit 60 includes, for example, a plurality of sets of planetary gear devices such as a first planetary gear device 74 and a second planetary gear device 76, and a plurality of clutches C1, C2, brakes B1 and B2 including a one-way clutch F1. and a known planetary gear type automatic transmission. Hereinafter, the clutch C1, the clutch C2, the brake B1, and the brake B2 will simply be referred to as an engagement device CB unless otherwise specified.

The engagement device CB is a hydraulic friction engagement device including a multi-plate or single-plate clutch or brake that is pressed by a hydraulic actuator, a band brake that is tightened by a hydraulic actuator, or the like. The engagement device CB is engaged by respective hydraulic pressures Pc1, Pc2, Pb1, Pb2 of the engagement device CB that are regulated output from a hydraulic control circuit 78 provided in the vehicle 10 (see FIG. 6, which will be described later). The operating state, which is a state such as engaging or disengaging, is switched.

In the stepped transmission portion 60, each rotating element of the first planetary gear device 74 and the second planetary gear device 76 is partially connected to each other directly or indirectly via the engagement device CB or the one-way clutch F1. , or connected to the intermediate transmission member 70 , the case 56 , or the output shaft 62 . The rotating elements of the first planetary gear set 74 are the sun gear S1, the carrier CA1 and the ring gear R1, and the rotating elements of the second planetary gear set 76 are the sun gear S2, the carrier CA2 and the ring gear R2.

The stepped transmission unit 60 changes the gear ratio (also referred to as gear ratio) γat (=AT input rotational speed Ni / A stepped transmission in which one of a plurality of gear stages (also referred to as gear stages) having different output rotation speeds (No) is formed. In other words, in the stepped transmission portion 60, a plurality of engagement devices are selectively engaged to switch gears, that is, to execute gear shifting. Stepped transmission portion 60 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 section 60 is called an AT gear stage. The AT input rotation speed Ni is the input rotation speed of the stepped transmission portion 60, which is the rotation speed of the input rotation member of the stepped transmission portion 60, and has the same value as the rotation speed of the intermediate transmission member 70. It has 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 represented by the MG2 rotation speed Nm. The output rotation speed No is the rotation speed of the output shaft 62, which is the output rotation speed of the stepped transmission section 60, and is a compound transmission that is the entire transmission combining the continuously variable transmission section 58 and the stepped transmission section 60. It is also the output rotational speed of machine 80 . Compound transmission 80 is a transmission that forms part of a power transmission path between engine 12 and drive wheels 14 .

For example, as shown in the engagement operation table of FIG. 3, the stepped transmission unit 60 has a plurality of AT gear stages, AT 1st gear ("1st" in the figure)-AT 4th gear ("4th" in the figure). ”) are formed. The transmission gear ratio γat of the AT 1st gear stage is the largest, and the transmission gear ratio γat becomes smaller with increasing AT gear stage. A reverse AT gear stage ("Rev" in the figure) is formed, for example, by engagement of the clutch C1 and engagement of the brake B2. That is, as will be described later, when the vehicle is traveling backward, for example, the AT 1st gear is set. The engagement operation table in FIG. 3 summarizes the relationship between each AT gear stage and each operation state of a plurality of engagement devices. That is, the engagement operation table of FIG. 3 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. 3 , “◯” indicates engagement, “Δ” indicates engagement during engine braking or during coast downshifting of the stepped transmission 60, and blank spaces indicate disengagement.

The stepped transmission unit 60 switches between AT gear stages according to the driver's accelerator operation, vehicle speed V, etc. by an electronic control unit 100, which will be described later. formed in For example, in the speed change control of the stepped speed change portion 60, the speed change is executed by changing the grip of any of the engagement devices CB, that is, the speed change is executed by switching between engagement and release of the engagement device CB. A so-called clutch-to-clutch shift is executed. In this embodiment, for example, a downshift from AT 2nd gear to AT 1st gear is expressed as a 2→1 downshift. The same is true for other upshifts and downshifts.

The vehicle 10 further includes a one-way clutch F0, a mechanical oil pump MOP82, an electric oil pump EOP84, and the like.

The one-way clutch F0 is a locking mechanism that can fix the carrier CA0 so that it cannot rotate. That is, the one-way clutch F0 is a locking mechanism that can fix the connecting shaft 68 that is connected to the crankshaft of the engine 12 and that rotates integrally with the carrier CA0 to the case 56 . The one-way clutch F0 has two members capable of relative rotation, one of which is integrally connected to the connecting shaft 68 and the other member is integrally connected to the case 56 . The one-way clutch F0 idles in the forward rotation direction, which is the rotation direction when the engine 12 is running, and automatically engages in the rotation direction opposite to when the engine 12 is running. Therefore, when the one-way clutch F0 is idling, the engine 12 is allowed to rotate relative to the case 56 . On the other hand, when the one-way clutch F<b>0 is engaged, the engine 12 cannot rotate relative to the case 56 . That is, the engine 12 is fixed to the case 56 by engaging the one-way clutch F0. Thus, the one-way clutch F0 permits rotation of the carrier CA0 in the positive rotation direction, which is the rotation direction during operation of the engine 12, and prevents rotation of the carrier CA0 in the negative rotation direction. That is, the one-way clutch F0 is a lock mechanism that allows rotation of the engine 12 in the positive rotation direction and prevents rotation in the negative rotation direction.

The MOP 82 is connected to the connecting shaft 68 , rotates with the rotation of the engine 12 , and discharges hydraulic oil used in the power transmission device 16 . The MOP 82 is rotated by the engine 12, for example, and discharges hydraulic oil. The EOP 84 is rotated by a motor 86 dedicated to an oil pump provided in the vehicle 10 to discharge hydraulic oil. Hydraulic oil discharged from the MOP 82 and the EOP 84 is supplied to the hydraulic control circuit 78 (see FIG. 6, which will be described later). The engagement device CB is switched between operating states by respective hydraulic pressures Pc1, Pc2, Pb1 and Pb2 regulated by the hydraulic control circuit 78 based on the hydraulic oil oil.

FIG. 4 is a collinear diagram showing the relative relationship between the rotational speeds of the rotating elements in the continuously variable transmission section 58 and the stepped transmission section 60. As shown in FIG. In FIG. 4, three vertical lines Y1, Y2, and Y3 corresponding to the three rotating elements of the differential mechanism 72 constituting the continuously variable transmission section 58 indicate, from the left side, the sun gear S0 corresponding to the second rotating element RE2. The g-axis represents the rotational speed, the e-axis represents the rotational speed of the carrier CA0 corresponding to the first rotating element RE1, and the rotational speed of the ring gear R0 corresponding to the third rotating element RE3 (that is, the speed of the stepped transmission section 60). input rotational speed). Also, the four vertical lines Y4, Y5, Y6, and Y7 of the stepped transmission section 60 indicate, from the left, the rotation speed of the sun gear S2 corresponding to the fourth rotating element RE4, and the rotation speed of the sun gear S2 corresponding to the fifth rotating element RE5. The rotation speed of the coupled ring gear R1 and carrier CA2 (that is, the rotation speed of the output shaft 62), the rotation speed of the coupled carrier CA1 and ring gear R2 corresponding to the sixth rotation element RE6, and the rotation speed corresponding to the seventh rotation element RE7 These axes represent the rotational speeds of the sun gear S1. The mutual intervals of the vertical lines Y1, Y2, Y3 are determined according to the gear ratio ρ0 of the differential mechanism 72. As shown in FIG. The distances between the vertical lines Y4, Y5, Y6 and Y7 are determined according to the gear ratios ρ1 and ρ2 of the first and second planetary gear units 74 and 76, respectively. If the distance between the sun gear and the carrier corresponds to "1" in the relationship between the vertical axes of the collinear chart, the gear ratio ρ (= number of teeth of the sun gear/ring gear) of the planetary gear system between the carrier and the ring gear is number of teeth).

4, in the differential mechanism 72 of the continuously variable transmission unit 58, the engine 12 (see "ENG" in the drawing) is connected to the first rotating element RE1, and the second rotating element A first rotating machine MG1 (see "MG1" in the drawing) is connected to RE2, and a second rotating machine MG2 (see "MG2" in the drawing) is connected to a third rotating element RE3 that rotates integrally with the intermediate transmission member 70. , and is configured to transmit the rotation of the engine 12 to the stepped transmission portion 60 via the intermediate transmission member 70 . In the continuously variable transmission portion 58, straight lines L0e, L0m, and L0R crossing the vertical line Y2 indicate the relationship between the rotational speed of the sun gear S0 and the rotational speed of the ring gear R0.

In the stepped transmission portion 60, the fourth rotating element RE4 is selectively connected to the intermediate transmission member 70 via the clutch C1, the fifth rotating element RE5 is connected to the output shaft 62, and the sixth rotating element RE6 is connected to the output shaft 62. It is selectively connected to the intermediate transmission member 70 via the clutch C2 and selectively connected to the case 56 via the brake B2, and the seventh rotating element RE7 is selectively connected to the case 56 via the brake B1. ing. In the stepped transmission portion 60, "1st", "2nd" and "3rd" on the output shaft 62 are controlled by the respective straight lines L1, L2, L3, L4 and LR crossing the vertical line Y5 under the engagement release control of the engagement device CB. , "4th" and "Rev" are shown.

A straight line L0e and straight lines L1, L2, L3, and L4 indicated by solid lines in FIG. 4 represent respective rotations during forward travel in a hybrid travel (=HV travel) mode in which hybrid travel is possible using at least the engine 12 as a power source. Indicates the relative velocity of the element. In this hybrid running mode, in the differential mechanism 72, MG1 torque Tg, which is a reaction torque of negative torque generated by the first rotary machine MG1, is input to the sun gear S0 with respect to the positive engine torque Te input to the carrier CA0. Then, an engine direct torque Td (=Te/(1+ρ0)=-(1/ρ0)×Tg) appears in the ring gear R0, which becomes a positive torque in forward rotation. 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 is any AT gear stage from the AT 1st gear stage to the AT 4th gear stage. is transmitted to the drive wheels 14 via the stepped transmission portion 60 formed with a . The first rotary machine MG1 functions as a generator when it generates negative torque in positive rotation. The electric power Wg generated by the first rotating machine MG1 is charged in the battery 54 or consumed by the second rotating machine MG2. The second rotary machine MG2 uses all or part of the generated power Wg, or uses power from the battery 54 in addition to the generated power Wg to output the MG2 torque Tm.

A straight line L0m indicated by a dashed dotted line in FIG. 4 and straight lines L1, L2, L3, and L4 indicated by solid lines in FIG. 1 shows the relative speed of each rotating element in forward running in a motor running (=EV running) mode in which motor running is possible using at least one of the rotary machines as a power source. Motor running in forward running in the motor running mode includes, for example, single-drive motor running in which only the second rotary machine MG2 is used as a power source, and running in which both the first rotary machine MG1 and the second rotary machine MG2 are used as power sources. There is a dual drive motor running. In single-drive motor running, the carrier CA0 is set to zero rotation, and the MG2 torque Tm, which becomes positive torque in forward rotation, is input to the ring gear R0. At this time, the first rotary machine MG1 connected to the sun gear S0 is brought into a no-load state and idled in a negative rotation. In single-drive motor running, the one-way clutch F0 is released and the connecting shaft 68 is not fixed to the case 56 . In dual-drive motor running, when the carrier CA0 is set to zero rotation and MG1 torque Tg, which becomes negative torque at negative rotation, is input to the sun gear S0, the carrier CA0 is prevented from rotating in the negative rotation direction. , the one-way clutch F0 is automatically engaged. In a state where carrier CA0 is non-rotatably fixed by engagement of one-way clutch F0, reaction torque due to MG1 torque Tg is input to ring gear R0. In addition, in dual-drive motor running, MG2 torque Tm is input to ring gear R0 in the same manner as in single-drive motor running. When the MG1 torque Tg, which becomes a negative torque at negative rotation, is input to the sun gear S0 in a state where the carrier CA0 is set to zero rotation, if the MG2 torque Tm is not input, single-drive motor running by the MG1 torque Tg is also possible. It is possible. In forward running in the motor running mode, the engine 12 is not driven, the engine rotation speed Ne is set to zero, and at least one of the MG1 torque Tg and the MG2 torque Tm is used as the driving torque in the forward direction of the vehicle 10. The power is transmitted to the drive wheels 14 via a stepped transmission section 60 in which any one of the AT 1st gear-AT 4th gear is formed. In forward running in the motor running mode, the MG1 torque Tg is power running torque of negative rotation and negative torque, and the MG2 torque Tm is power running torque of positive rotation and positive torque.

A straight line L0R and a straight line LR indicated by dashed lines in FIG. 4 indicate the relative speed of each rotating element during reverse travel in the motor travel mode. During reverse travel in this motor travel mode, MG2 torque Tm, which becomes negative torque at negative rotation, is input to the ring gear R0, and the MG2 torque Tm serves as the drive torque in the reverse direction of the vehicle 10, forming the AT 1st gear stage. The power is transmitted to the drive wheels 14 via the stepped transmission unit 60 . In the vehicle 10, an electronic control unit 100, which will be described later, is in a state in which a forward low-side AT gear stage, for example, an AT 1st gear stage, is formed among a plurality of AT gear stages. The second rotating machine MG2 outputs the reverse MG2 torque Tm, which is opposite in polarity to the MG2 torque Tm, so that the vehicle can travel in reverse. In reverse running in the motor running mode, the MG2 torque Tm is power running torque of negative rotation and negative torque. Also in the hybrid running mode, it is possible to rotate the second rotary machine MG2 in the negative direction as in the straight line L0R, so that backward running can be performed in the same manner as in the motor running mode.

In the power transmission device 16, a carrier CA0 as a first rotating element RE1 to which the engine 12 is coupled so as to be able to transmit power, a sun gear S0 as a second rotating element RE2 to which is coupled so as to be able to transmit power to the first rotary machine MG1, and an intermediate gear S0. A differential mechanism 72 having three rotating elements including a ring gear R0 as a third rotating element RE3 to which a transmission member 70 is coupled is provided, and the differential mechanism 72 is operated by controlling the operating state of the first rotating machine MG1. A continuously variable transmission portion 58 is configured as an electric transmission mechanism in which the differential state of is controlled. In other words, the third rotating element RE3 to which the intermediate transmission member 70 is connected is the third rotating element RE3 to which the second rotating machine MG2 is connected so as to be able to transmit power. That is, the power transmission device 16 includes the differential mechanism 72 to which the engine 12 is connected so as to be able to transmit power, and the first rotating machine MG1 to which the differential mechanism 72 is connected so as to be able to transmit power. Continuously variable transmission portion 58 is configured in which the differential state of differential mechanism 72 is controlled by controlling the operating state of MG1. The continuously variable transmission unit 58 is the ratio of the engine rotation speed Ne, which is the same value as the rotation speed of the connecting shaft 68, which is the input rotation member, and the MG2 rotation speed Nm, which is the rotation speed of the intermediate transmission member 70 which is the output rotation member. It is operated as an electric continuously variable transmission in which the gear ratio γ0 (=Ne/Nm), which is a value, can be varied.

For example, in the hybrid running mode, the rotation speed of the first rotary machine MG1 is higher than the rotation speed of the ring gear R0, which is restrained by the rotation of the drive wheels 14 due to the formation of the AT gear stage in the stepped transmission unit 60. When the rotation speed of the sun gear S0 is increased or decreased by controlling , the rotation speed of the carrier CA0, that is, the engine rotation speed Ne is increased or decreased. Therefore, in hybrid running, the engine 12 can be operated at the efficient engine operating point OPeng. The operating point is an operating point represented by the rotational speed and torque, and the engine operating point OPeng is the operating point of the engine 12 represented by the engine rotational speed Ne and the engine torque Te. In the power transmission device 16, the continuously variable transmission portion 58 and the stepped transmission portion 60 are connected in series by the stepped transmission portion 60 in which the AT gear stage is formed and the continuously variable transmission portion 58 operated as a continuously variable transmission. The arranged compound transmission 80 as a whole can constitute a continuously variable transmission.

Alternatively, since it is possible to shift the continuously variable transmission portion 58 like a stepped transmission, in the power transmission device 16, the stepped transmission portion 60 in which the AT gear stage is formed and the stepped transmission like a stepped transmission Together with the continuously variable transmission portion 58, the compound transmission 80 as a whole can be changed like a stepped transmission. That is, in the compound transmission 80, a stepped transmission is performed so as to selectively establish a plurality of gear stages having different gear ratios γt (=Ne/No) representing the ratio of the engine rotation speed Ne to the output rotation speed No. It is possible to control the section 60 and the continuously variable transmission section 58 . In this embodiment, the gear stage established by the compound transmission 80 is called a simulated gear stage. A gear ratio γt is a total gear ratio formed by the continuously variable transmission portion 58 and the stepped transmission portion 60 arranged in series, and is the total gear ratio formed by the stepless transmission portion 58 and the stepped transmission portion 60. It becomes a value (γt=γ0×γat) multiplied by the gear ratio γat.

The simulated gear stage is set for each AT gear stage of the stepped transmission section 60 by, for example, combining each AT gear stage of the stepped transmission section 60 with one or more gear ratios γ0 of the continuously variable transmission section 58. Assigned to establish one or more types. For example, FIG. 5 is an example of a gear stage assignment table. In FIG. 5, in the upshift of the compound transmission 80, the simulated 1st gear-simulated 3rd gear is established for the AT 1st gear, and the simulated 4th gear-simulated for the AT 2nd gear. 6th gear stage is established, simulated 7th gear stage-simulated 9th gear stage is established for AT 3rd gear stage, and simulated 10th gear stage is established for AT 4th gear stage. Predetermined. Further, in the downshift of the compound transmission 80, the simulated 1st gear stage-simulated 2nd gear stage is established for the AT 1st gear stage, and the simulated 3rd gear stage-simulated 5th gear stage are established for the AT 2nd gear stage. A gear stage is established, a simulated 6th gear stage-a simulated 8th gear stage is established for an AT 3rd gear stage, and a simulated 9th gear stage-a simulated 10th gear stage is established for an AT 4th gear stage. It is determined in advance so that In the compound transmission 80, the continuously variable transmission unit 58 is controlled so that the engine rotation speed Ne that realizes a predetermined transmission gear ratio γt with respect to the output rotation speed No. is established. Further, in the compound transmission 80, the simulated gear stage is switched by controlling the continuously variable transmission section 58 in accordance with the switching of the AT gear stage. Note that FIG. 5 shows an example in which the simulated gear stages assigned to the AT gear stages are different between upshifts and downshifts, but they may be the same.

Returning to FIG. 1, the vehicle 10 includes an electronic control unit 100 as a controller including control units of the vehicle 10 related to control of the engine 12, the continuously variable transmission section 58, the stepped transmission section 60, and the like. Therefore, FIG. 1 is a diagram showing an input/output system of the electronic control unit 100, and is also a functional block diagram explaining the main control functions of the electronic control unit 100. As shown in FIG. The electronic control unit 100 includes, for example, a so-called microcomputer having a CPU, a RAM, a ROM, and an input/output interface. Various controls of the vehicle 10 are executed by performing signal processing. The electronic control unit 100 includes computers for engine control, rotary machine control, hydraulic control, etc., as required.

The electronic control unit 100 includes various sensors provided in the vehicle 10 (for example, the air flow meter 34, the boost pressure sensor 40, the intake air temperature sensor 42, the throttle valve opening sensor 44, the engine speed sensor 88, the output speed sensor, etc.). 90, each wheel speed sensor 91, MG1 rotation speed sensor 92, MG2 rotation speed sensor 94, MG1 temperature sensor 95, MG2 temperature sensor 96, accelerator opening sensor 97, battery sensor 98, oil temperature sensor 99, etc.) Various signals (for example, intake air amount Qair, supercharging pressure Pchg, intake air temperature THair, throttle valve opening θth, engine rotation speed Ne, output rotation speed No corresponding to vehicle speed V, left and right drive wheels 14 and left and right unevenness) Wheel speeds Nwdl, Nwdr, Nwsl, Nwsr, which are the wheel speeds Nw of the driven wheels shown in the figure; MG1 rotation speed Ng, which is the rotation speed of the first rotary machine MG1; MG2 rotation speed Nm, which has the same value as the AT input rotation speed Ni; MG1 temperature THg, which is the temperature of the first rotary machine MG1, for example, the stator temperature; MG2 temperature THm, which is the temperature of the second rotary machine MG2, for example the stator temperature; The accelerator opening θacc, the battery temperature THbat of the battery 54, the battery charge/discharge current Ibat, the battery voltage Vbat, the working oil temperature THoil which is the temperature of the working oil oil, etc.) are supplied.

Various command signals (for example, an engine control command for controlling the engine 12) are sent from the electronic control unit 100 to each device (for example, the engine control unit 50, the inverter 52, the hydraulic control circuit 78, the motor 86, etc.) provided in the vehicle 10. A signal Se, a rotary machine control command signal Smg for controlling the first rotary machine MG1 and the second rotary machine MG2, a hydraulic control command signal Sat for controlling the operating state of the engagement device CB, and controlling the operation of the EOP84. EOP control command signal Seop, etc.) are respectively output. This hydraulic control command signal Sat is also a hydraulic control command signal for controlling the speed change of the stepped transmission section 60. For example, the hydraulic pressures Pc1, Pc2, Pb1, Pb2 supplied to the respective hydraulic actuators of the engagement device CB. is a command signal for driving the solenoid valves SL1-SL4, etc. (see FIG. 6, which will be described later) for regulating the pressure. The electronic control unit 100 sets oil pressure command values corresponding to the respective oil pressure values Pc1, Pc2, Pb1, Pb2, and outputs a drive current or a drive voltage to the oil pressure control circuit 78 according to the oil pressure command values.

The electronic control unit 100 calculates a state-of-charge value SOC [%] as a value indicating the state of charge of the battery 54 based on, for example, the battery charging/discharging current Ibat and the battery voltage Vbat. Further, the electronic control unit 100 calculates chargeable/dischargeable power Win, Wout that defines the usable range of the battery power Pbat, which is the power of the battery 54, based on the battery temperature THbat and the state of charge value SOC of the battery 54, for example. do. The chargeable/dischargeable power Win and Wout are the chargeable 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/dischargeable electric powers Win and Wout are reduced as the battery temperature THbat decreases in a low temperature range lower than the normal use range, and decrease as the battery temperature THbat increases in a high temperature range higher than the normal use range. be done. Also, the chargeable power Win is made smaller as the state of charge value SOC is higher in a region where the state of charge value SOC is higher, for example. Further, the dischargeable power Wout is made smaller as the state-of-charge value SOC becomes lower, for example, in a region where the state-of-charge value SOC is lower.

FIG. 6 is a diagram for explaining the hydraulic control circuit 78 and also for explaining a hydraulic source for supplying hydraulic oil to the hydraulic control circuit 78. As shown in FIG. In FIG. 6, the MOP 82 and the EOP 84 are provided in parallel due to the configuration of the oil passage through which the hydraulic oil flows. Each of the MOP 82 and the EOP 84 discharges hydraulic oil that serves as a source of hydraulic pressure for switching the operating state of each of the engagement devices CB and supplying lubricating oil to each part of the power transmission device 16 . Each of the MOP 82 and EOP 84 sucks up the hydraulic oil that has flowed back to the oil pan 120 provided at the bottom of the case 56 through a strainer 122, which is a common suction port, and discharges it to each of the discharge oil passages 124, 126. do. The discharge oil passages 124 and 126 are each connected to an oil passage provided in the hydraulic control circuit 78, for example, a line pressure oil passage 128 through which the line pressure PL flows. A discharge oil passage 124 through which hydraulic oil is discharged from the MOP 82 is connected to a line pressure oil passage 128 via a MOP check valve 130 provided in the hydraulic control circuit 78 . A discharge oil passage 126 through which hydraulic oil is discharged from the EOP 84 is connected to a line pressure oil passage 128 via an EOP check valve 132 provided in the hydraulic control circuit 78 . The MOP 82 rotates together with the engine 12 and is driven to rotate by the engine 12 to generate working oil pressure. The EOP 84 is driven to rotate by the motor 86 regardless of the rotational state of the engine 12 to generate working oil pressure. The EOP 84 is activated, for example, during running in the motor running mode.

The hydraulic control circuit 78 includes a regulator valve 134, solenoid valves SLT, SL1-SL4, etc. in addition to the line pressure oil passage 128, the MOP check valve 130, and the EOP check valve 132 described above.

The regulator valve 134 regulates the line pressure PL based on the working oil discharged by at least one of the MOP 82 and the EOP 84 . The solenoid valve SLT is, for example, a linear solenoid valve, and is controlled by the electronic control unit 100 so as to output the pilot pressure Pslt to the regulator valve 134 according to the accelerator opening θacc or the input torque to the stepped transmission unit 60. . In the regulator valve 134, the spool 136 is energized by the pilot pressure Pslt, and the spool 136 is moved in the axial direction as the opening area of the discharge passage 138 changes, thereby increasing the line pressure in accordance with the pilot pressure Pslt. PL is regulated. As a result, the line pressure PL is set to a hydraulic pressure corresponding to the accelerator opening θacc, the input torque of the stepped transmission 60, or the like. The source pressure input to the solenoid valve SLT is a modulator pressure PM adjusted to a constant value by a modulator valve (not shown) using, for example, the line pressure PL as the source pressure.

Each of the solenoid valves SL1-SL4 is, for example, a linear solenoid valve, and uses the line pressure PL supplied through the line pressure oil passage 128 as a source pressure to change the hydraulic pressures Pc1, Pc2, Pb1, Pb2 of the engagement device CB. It is controlled by the electronic control unit 100 to output. A solenoid valve SL1 regulates the C1 oil pressure Pc1 supplied to the hydraulic actuator of the clutch C1. A solenoid valve SL2 regulates the C2 oil pressure Pc2 supplied to the hydraulic actuator of the clutch C2. A solenoid valve SL3 regulates the B1 oil pressure Pb1 supplied to the hydraulic actuator of the brake B1. A solenoid valve SL4 regulates the B2 oil pressure Pb2 supplied to the hydraulic actuator of the brake B2.

Returning to FIG. 1 , the electronic control unit 100 includes AT shift control means, ie AT shift control section 102 , and hybrid control means, ie hybrid control section 104 , in order to implement various controls in the vehicle 10 .

The AT shift control unit 102 determines the shift of the stepped shift unit 60 using, for example, an AT gear stage shift map, which is a relation that is experimentally or design-determined and stored in advance, i.e., a predetermined relationship, and The speed change control of the stepped speed change portion 60 is executed as required. In the shift control of the stepped speed change portion 60, the AT speed change control portion 102 sets the engagement device CB to the disengaged state by the solenoid valves SL1 to SL4 so that the AT gear stage of the stepped speed change portion 60 is automatically switched. A hydraulic control command signal Sat for switching is output to the hydraulic control circuit 78 . The AT gear stage shift map has a predetermined relationship having a shift line for judging the shift of the stepped transmission section 60 on two-dimensional coordinates having variables such as the output rotation speed No and the accelerator opening θacc. . Here, the vehicle speed V or the like may be used instead of the output rotation speed No, and the required driving torque Twdem or the throttle valve opening θth may be used instead of the accelerator opening θacc. Each shift line in the AT gear stage shift map is an upshift line for judging an upshift and a downshift line for judging a downshift. Whether or not the output rotation speed No crosses a line indicating a certain accelerator opening θacc, or whether or not the accelerator opening θacc crosses a line indicating a certain output rotation speed No, That is, it is for judging whether or not a shift point, which is a value at which a shift on the shift line should be executed, has been crossed, and is predetermined as a series of shift points.

The hybrid control unit 104 functions as engine control means for controlling the operation of the engine 12, that is, as an engine control unit, and a rotary machine control means for controlling the operations of the first rotary machine MG1 and the second rotary machine MG2 via the inverter 52. In other words, it includes a function as a rotating machine control unit, and executes hybrid drive control by the engine 12, the first rotating machine MG1, and the second rotating machine MG2 by these control functions.

The hybrid control unit 104 calculates a required driving torque Twdem, which is the driving torque Tw required for the vehicle 10, by applying the accelerator opening θacc and the vehicle speed V to a predetermined relationship, for example, a driving force map. . This required driving torque Twdem is, in other words, the required driving power Pwdem at the vehicle speed V at that time. Here, instead of the vehicle speed V, the output rotational speed No or the like may be used. The hybrid control unit 104 controls at least one of the engine 12, the first rotating machine MG1, and the second rotating machine MG2 in consideration of the required charging/discharging power, which is the charging/discharging power required for the battery 54. An engine control command signal Se, which is a command signal for controlling the engine 12, and a rotary machine control, which is a command signal for controlling the first rotary machine MG1 and the second rotary machine MG2, so that the required driving power Pwdem is realized by the power source. It outputs a command signal Smg. The engine control command signal Se is, for example, a command value of the engine power Pe, which is the power of the engine 12 that outputs the engine torque Te at the engine rotation speed Ne at that time. The rotating machine control command signal Smg is, for example, a command value of the generated power Wg of the first rotating machine MG1 that outputs the MG1 torque Tg at the MG1 rotation speed Ng at the time of command output as reaction torque of the engine torque Te, and 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 when the command is output.

For example, when the continuously variable transmission unit 58 is operated as a continuously variable transmission and the entire compound transmission 80 is operated as a continuously variable transmission, the hybrid control unit 104 adds the required charging/discharging power to the required driving power Pwdem and the charging/discharging power of the battery 54 . The engine 12 is controlled to achieve the engine power Pe that outputs the target engine torque Tetgt at the target engine rotation speed Netgt considering the optimum engine operating point OPengf and the like, which realizes the required engine power Pedem in consideration of the discharge efficiency and the like. In addition, the hybrid control unit 104 controls the electric power Wg generated by the first rotary machine MG1 so as to output the MG1 torque Tg for setting the engine speed Ne to the target engine speed Netgt. 58 is executed to change the transmission gear ratio γ0 of the continuously variable transmission section 58 . As a result of this control, the gear ratio γt of the compound transmission 80 when operated as a continuously variable transmission is controlled. The MG1 torque Tg when the compound transmission 80 as a whole operates as a continuously variable transmission is calculated, for example, in feedback control for operating the first rotary machine MG1 so that the engine speed Ne becomes the target engine speed Netgt. The MG2 torque Tm when the compound transmission 80 as a whole operates as a continuously variable transmission is calculated so as to obtain the required driving torque Twdem together with the driving torque Tw due to the engine direct torque Td, for example.

The optimum engine operating point OPengf is predetermined as an engine operating point OPeng at which the total fuel consumption of the vehicle 10 is the best, taking into consideration the fuel consumption of the engine 12 alone and the charge/discharge efficiency of the battery 54, etc., when realizing the required engine power Pedem, for example. It is The target engine rotation speed Netgt is the target value of the engine rotation speed Ne, and the target engine torque Tetgt is the target value of the engine torque Te.

FIG. 7 is a diagram showing an example of the optimum engine operating point OPengf on two-dimensional coordinates with the engine speed Ne and the engine torque Te as variables. In FIG. 7, a solid line Leng indicates a collection of optimum engine operating points OPengf. Equal power lines Lpw1, Lpw2 and Lpw3 respectively show examples when the required engine power Pedem is the required engine power Pe1, Pe2 and Pe3. Point A is the engine operating point OPengA when the requested engine power Pe1 is realized at the optimum engine operating point OPengf, and point B is the engine operating point when the requested engine power Pe3 is realized at the optimum engine operating point OPengf. It is OPengB. The points A and B are also the target values of the engine operating point OPeng represented by the target engine rotation speed Netgt and the target engine torque Tetgt, that is, the target engine operating point OPengtgt. When, for example, the target engine operating point OPengtgt is changed from point A to point B due to an increase in the accelerator opening θacc, control is performed so that the engine operating point OPeng is changed along a path a passing over the optimum engine operating point OPengf. be.

For example, in the case where the continuously variable transmission unit 58 is shifted like a stepped transmission and the entire compound transmission 80 is shifted like a stepped transmission, the hybrid control unit 104 controls a predetermined relationship, such as a simulated gear. A step shift map is used to determine the shift of the compound transmission 80, and a plurality of simulated gear stages are selectively established in cooperation with shift control of the AT gear stages of the stepped transmission section 60 by the AT shift control section 102. The speed change control of the stepless speed change portion 58 is executed as follows. A plurality of simulated gear stages can be established by controlling the engine rotation speed Ne by the first rotary machine MG1 in accordance with the output rotation speed No so as to maintain the gear ratio γt. The gear ratio γt of each simulated gear stage does not necessarily have to be a constant value over the entire output rotational speed No. It may be varied within a predetermined region, and is limited by the upper and lower limits of the rotational speed of each section. May be added. A plurality of simulated gear stages can be established simply by controlling the engine rotation speed Ne according to the output rotation speed No, and a predetermined simulated gear stage can be established regardless of the type of AT gear stage of the stepped transmission section 60. can. In this manner, the hybrid control unit 104 can perform speed change control to change the engine rotation speed Ne like a stepped speed change.

Similar to the AT gear shift map, the simulated gear shift map is predetermined using the output rotation speed No and the accelerator opening θacc as parameters. FIG. 8 is an example of a simulated gear shift map, where the solid line is the upshift line and the broken line is the downshift line. By switching the simulated gear stages according to the simulated gear stage shift map, the entire compound transmission 80 in which the continuously variable transmission section 58 and the stepped transmission section 60 are arranged in series has a shift feel similar to that of a stepped transmission. can get. The simulated stepped transmission control for shifting the entire compound transmission 80 like a stepped transmission is performed, for example, when the driver selects a driving mode emphasizing driving performance, such as a sports driving mode, or when the required drive torque Twdem is relatively low. If it is large, the stepless speed change control may be executed with priority to operate the compound transmission 80 as a whole as a continuously variable transmission. May be.

The simulated stepped speed change control by hybrid control unit 104 and the speed change control of stepped speed change unit 60 by AT speed change control unit 102 are executed in cooperation. In this embodiment, 10 simulated gear stages of simulated 1st gear stage to simulated 10th gear stage are assigned to 4 types of AT gear stages of AT 1st gear stage to AT 4th gear stage. Therefore, the AT gear shift map is defined so that the shift to the AT gear is performed at the same timing as the shift timing of the simulated gear. Specifically, the upshift lines of "3→4", "6→7" and "9→10" of the simulated gear stages in FIG. →3” and “3→4” (see “AT1→2” etc. shown in FIG. 8). Further, the downshift lines of "2←3", "5←6" and "8←9" of the simulated gear stages in Fig. 8 correspond to "1←2" and "2←3" of the AT gear stage shift map. , "3←4" (see "AT1←2" and the like shown in FIG. 8). Alternatively, an AT gear shift command may be output to the AT shift control unit 102 based on the simulated gear shift determination based on the simulated gear shift map of FIG. Thus, when the stepped transmission portion 60 is upshifted, the entire compound transmission 80 is upshifted, while when the stepped transmission portion 60 is downshifted, the entire compound transmission 80 is downshifted. will be The AT shift control section 102 switches the AT gear stage of the stepped transmission section 60 when the simulated gear stage is switched. Since the shift to the AT gear stage is performed at the same timing as the shift timing of the simulated gear stage, the gear shift of the stepped transmission section 60 is performed along with the change in the engine rotation speed Ne. Even if there is a shock associated with shifting, the driver is less likely to feel uncomfortable.

The hybrid control unit 104 selectively establishes the motor driving mode or the hybrid driving mode as the driving mode according to the driving state, and drives the vehicle 10 in each driving mode. For example, hybrid control unit 104 establishes the motor running mode when the required driving power Pwdem is in the motor running region smaller than the predetermined threshold, while the required driving power Pwdem is equal to or greater than the predetermined threshold. is in the hybrid running region, the hybrid running mode is established. Even when the required driving power Pwdem is in the motor driving range, the hybrid control unit 104 operates when the state of charge value SOC of the battery 54 is less than a predetermined engine start threshold or when the engine 12 needs to be warmed up. In some cases, the hybrid running mode is established. The engine start threshold is a predetermined threshold for determining the state of charge value SOC at which it is necessary to forcibly start the engine 12 and charge the battery 54 .

FIG. 9 is a diagram showing an example of a power source switching map used for switching control between motor running and hybrid running. In FIG. 9, a solid line Lswp is a boundary line between a motor driving region and a hybrid driving region for switching between motor driving and hybrid driving. A region in which the vehicle speed V is relatively low, the required drive torque Twdem is relatively small, and the required drive power Pwdem is relatively small is predetermined in the motor drive region. A region in which the vehicle speed V is relatively high or the required drive torque Twdem is relatively large and the required drive power Pwdem is relatively large is predetermined as the hybrid travel region. When the state-of-charge value SOC of the battery 54 is less than the engine start threshold or when the engine 12 needs to be warmed up, the motor driving range in FIG. 9 may be changed to the hybrid driving range.

When the motor driving mode is established, the hybrid control unit 104 drives the vehicle 10 by single-drive motor driving by the second rotating machine MG2 when the required driving power Pwdem can be realized only by the second rotating machine MG2. Let On the other hand, when the motor drive mode is established, the hybrid control unit 104 causes the vehicle 10 to travel in the dual drive motor travel mode if the required drive power Pwdem cannot be achieved only with the second rotary machine MG2. Even when the required drive power Pwdem can be achieved only by the second rotary machine MG2, the hybrid control unit 104 uses the first rotary machine MG1 and the second rotary machine MG2 together rather than using only the second rotary machine MG2. If it is more efficient, the vehicle 10 may be run with both drive motors running.

The hybrid control unit 104 performs starting control for starting the engine 12 when the hybrid running mode is established when the operation of the engine 12 is stopped. When the engine 12 is started, the hybrid control unit 104 increases the engine rotation speed Ne by, for example, the first rotary machine MG1, and ignites when the engine rotation speed Ne reaches or exceeds a predetermined rotation speed at which ignition is possible. Start engine 12 . That is, the hybrid control unit 104 starts the engine 12 by cranking the engine 12 using the first rotary machine MG1.

The hybrid control unit 104 controls the accelerator operation by the driver (for example, the accelerator opening θacc, the decreasing speed of the accelerator opening θacc), the vehicle speed V, the gradient of the downhill road, and the brake operation by the driver for activating the wheel brake (for example, the brake The target deceleration is set based on the operation amount, brake operation speed, etc. Hybrid control unit 104 generates braking torque for vehicle 10 so that the set target deceleration is achieved. The braking torque of the vehicle 10 is generated by, for example, regenerative torque by the second rotary machine MG2, wheel braking torque by a wheel braking device (not shown), engine braking torque by the engine 12, and the like. The braking torque of the vehicle 10 is preferentially generated by the regenerative torque of the second rotary machine MG2, for example, from the viewpoint of improving fuel efficiency. The braking torque of the vehicle 10 is set when the regenerative torque of the second rotary machine MG2 is limited due to factors such as the state of charge value SOC of the battery 54 being high, and/or when a large target deceleration is set. is generated at the wheel braking torque and/or the engine braking torque instead of or in addition to the regenerative torque. When generating engine braking torque during motor running, the hybrid control unit 104 raises the engine rotation speed Ne by the first rotary machine MG1 while the operation of the engine 12 is stopped. to generate the desired engine braking torque.

Here, the hybrid control unit 104 controls the engine 12 and the first rotary machine so that the engine rotation speed Ne does not exceed the engine upper limit rotation speed Nelim and the MG1 rotation speed Ng does not exceed the MG1 upper limit rotation speed Nglim. Control MG1. The engine upper limit rotational speed Nelim is a predetermined upper limit rotational speed defined by a predetermined rating of the engine 12, for example, to prevent the performance of the engine 12 from deteriorating. The MG1 upper limit rotation speed Nglim is a predetermined upper limit rotation speed defined by a predetermined rating of the first rotary machine MG1, for example, for making it difficult for the performance of the first rotary machine MG1 to deteriorate. As is clear from the alignment chart shown in FIG. 4, the engine rotation speed Ne and the MG1 rotation speed Ng are mutually related. Not only the engine rotation speed Ne but also the MG1 rotation speed Ng can be prevented from exceeding the MG1 upper limit rotation speed Nglim.

FIG. 10 is a diagram showing an example of a usable region of the engine rotation speed Ne on two-dimensional coordinates having the vehicle speed V and the engine rotation speed Ne as variables. FIG. 10 is a diagram showing an example of the usable range of the engine rotation speed Ne when the stepped transmission unit 60 is in the AT 1st gear. In FIG. 10, in the low range of the vehicle speed V, that is, the output rotation speed No, when the engine rotation speed Ne increases, the MG1 rotation speed Ng reaches the MG1 upper limit rotation speed before the engine rotation speed Ne exceeds the engine upper limit rotation speed Nelim. Since it exceeds Nglim, the usable region of the engine rotation speed Ne is defined by the MG1 upper limit rotation speed Nglim. As the vehicle speed V increases, the usable range of the engine rotation speed Ne defined by the MG1 upper limit rotation speed Nglim is widened to the high rotation side of the engine rotation speed Ne. Since there is speed, in the middle vehicle speed range, the usable range of the engine rotation speed Ne is defined by the engine upper limit rotation speed Nelim. On the other hand, in the low range of the engine rotation speed Ne, when the output rotation speed No increases, the rotation speed of the second pinion P2 and the rotation speed of the carrier CA2 corresponding to the engine rotation speed Ne, that is, the rotation speed of the second pinion P2 Since the relative rotation speed Np2 of the second pinion P2, which is the absolute value of the rotation speed difference from the revolution rotation speed, increases, the engine rotation speed Ne is caused by the pinion upper limit relative rotation speed Np2lim of the relative rotation speed Np2 of the second pinion P2. defines the usable area. The pinion upper limit relative rotation speed Np2lim of the relative rotation speed Np2 of the second pinion P2 is, for example, a predetermined upper limit rotation speed for making it difficult for the performance of the second pinion P2 to deteriorate. As the engine rotation speed Ne increases, the usable region of the engine rotation speed Ne defined by the pinion upper limit relative rotation speed Np2lim of the relative rotation speed Np2 of the second pinion P2 is widened toward the high vehicle speed side. Since the second rotary machine MG2 also has a predetermined upper limit rotation speed, the usable range of the engine rotation speed Ne is defined by the MG2 upper limit rotation speed Nmlim in the high vehicle speed range. The MG2 upper limit rotation speed Nmlim is a predetermined upper limit rotation speed defined by a predetermined rating of the second rotary machine MG2, for example, to prevent deterioration of the performance of the second rotary machine MG2.

If the engine rotation speed Ne does not exceed the upper limit rotation speed in the usable range of the engine rotation speed Ne as shown in FIG. Ng can be kept from exceeding the MG1 upper limit rotation speed Nglim. In the present embodiment, the engine rotation speed Ne does not exceed the engine upper limit rotation speed Nelim, and the MG1 rotation speed Ng does not exceed the MG1 upper limit rotation speed Nglim. 104 is controlled so that the engine rotation speed Ne is within a range not exceeding the allowable maximum rotation speed Nemax of the engine rotation speed Ne, which is set lower than the upper limit rotation speed in the usable range of the engine rotation speed Ne by a margin α. do. The margin α is, for example, a margin of the engine rotation speed Ne determined in advance so that the engine rotation speed Ne and the MG1 rotation speed Ng do not exceed their respective predetermined upper limit rotation speeds. By controlling the engine 12 within a range not exceeding the allowable maximum rotation speed Nemax, the first rotary machine MG1 does not exceed the allowable maximum rotation speed Ngmax of the MG1 rotation speed Ng obtained by subtracting the margin β from the MG1 upper limit rotation speed Nglim. controlled within range. The margin β is, for example, a predetermined allowance for the MG1 rotation speed Ng so that the MG1 rotation speed Ng does not exceed the MG1 upper limit rotation speed Nglim.

Also, the MG2 rotation speed Nm that defines the usable range in the high vehicle speed range can be more appropriately set so as not to exceed the MG2 upper limit rotation speed Nmlim. is controlled within a range not exceeding the permissible maximum rotation speed Nmmax of the MG2 rotation speed Nm, which is set lower by the margin γ. The margin γ is, for example, a margin of the MG2 rotation speed Nm determined in advance so that the MG2 rotation speed Nm does not exceed the MG2 upper limit rotation speed Nmlim. The same applies to the relative rotational speed Np2 of the second pinion P2.

Further, the vehicle 10 is provided with a stepped transmission section 60 in series on the rear stage side of the continuously variable transmission section 58 . Therefore, when the AT gear stage of the stepped transmission portion 60 is switched at a certain vehicle speed V, the rotation speed of the ring gear R0, which is the output rotation speed of the continuously variable transmission portion 58, is changed. Then, the usable range of the engine rotation speed Ne is changed depending on the difference in the AT gear stages of the stepped transmission section 60 .

11, 12, and 13 each show an example of the usable range of the engine rotation speed Ne on two-dimensional coordinates with the vehicle speed V and the engine rotation speed Ne as variables. is a diagram showing a case different from the case of AT 1st gear. 11 shows the case where the stepped transmission section 60 is in the AT 2nd gear stage, FIG. 12 shows the case where the stepped transmission section 60 is in the AT 3rd gear stage, and FIG. 13 shows the case where the stepped transmission section 60 is in the AT 4th gear stage. This is the case of stage time. In FIGS. 11, 12, and 13, the basic concept of defining the usable range of the engine rotation speed Ne is as explained with reference to FIG. At a certain vehicle speed V, the higher the AT gear stage of the stepped transmission portion 60 is, the lower the rotation speed of the ring gear R0, which is the output rotation speed of the continuously variable transmission portion 58. Therefore, in the low range of the engine speed Ne, the higher the AT gear stage is, the more the engine speed Ne defined by the pinion upper limit relative speed Np2lim of the relative speed Np2 of the second pinion P2 is used. The possible area is widened on the high vehicle speed side. In the case of AT 3rd gear stage or AT 4th gear stage, the rotation speed of the ring gear R0 is reduced, so that the engine rotation speed Ne is not defined in the usable range due to the MG2 upper limit rotation speed Nmlim, but the vehicle The maximum vehicle speed at 10 defines the usable range of the engine rotation speed Ne. Since the MG1 rotation speed Ng tends to increase when the rotation speed of the ring gear R0 is lowered because the AT gear stage of the stepped transmission portion 60 is on the high side, in the low vehicle speed range, the higher the AT gear stage, the higher the speed. In the usable region of the engine rotation speed Ne defined by the MG1 upper limit rotation speed Nglim, the restriction on the high rotation side is increased.

The aforementioned target engine operating point OPengtgt is set as the engine operating point OPeng for realizing the required engine power Pedem, but it is also taken into consideration that the engine rotation speed Ne is within a range that does not exceed the allowable maximum rotation speed Nemax. is set. The hybrid control unit 104 sets the engine operating point OPeng to a permissible maximum rotation speed in which a margin (=margin α) is secured for the engine rotation speed Ne with respect to the predetermined upper limit rotation speeds of the engine 12 and the first rotary machine MG1. The engine 12 and the first rotary machine MG1 are adjusted so that the engine rotation speed Ne is within a range not exceeding Nemax and the target engine operating point OPengtgt is set so that the required engine power Pedem is output from the engine 12. to control. Control of the engine 12 is, for example, control of the engine torque Te for outputting the target engine torque Tetgt. The control of the first rotary machine MG1 is, for example, control of the MG1 torque Tg by feedback control that operates the first rotary machine MG1 so that the engine speed Ne becomes the target engine speed Netgt.

By the way, in the vehicle 10, depending on the vehicle state, there is a possibility that the second rotary machine MG2 will be in a high rotation state to the extent that it reaches the MG2 upper limit rotation speed Nmlim. On the other hand, in order to prevent the second rotary machine MG2 from entering such a high rotational speed state, the allowable maximum rotation speed Nmmax is set so that a margin of the MG2 rotation speed Nm is secured with respect to the MG2 upper limit rotation speed Nmlim. , the engine torque Te may be reduced. However, since the engine 12 has the supercharger 18, the response delay of the boost pressure Pchg causes the response delay of the engine torque Te. Also, there is a possibility that the MG2 rotation speed Nm of the second rotary machine MG2 may easily fall into a high rotation state to the extent that it reaches the MG2 upper limit rotation speed Nmlim. Therefore, this embodiment is designed to prevent the MG2 rotation speed Nm from falling into a high rotation state where the MG2 rotation speed Nm reaches the MG2 upper limit rotation speed Nmlim, that is, the high rotation state where the MG2 rotation speed Nm exceeds the allowable maximum rotation speed Nmmax. , when the actual rotational speed difference ΔN [rpm], which is the rotational speed difference between the allowable maximum rotational speed Nmmax and the MG2 rotational speed Nm, becomes equal to or less than the marginal rotational speed difference ΔNr [rpm], the actual rotational speed difference ΔN is increased. , the gear ratio γat of the stepped transmission unit 60 is changed.

Specifically, the electronic control unit 100 causes the AT transmission control unit 102 to change the transmission gear ratio in order to realize the control function of suppressing the MG2 rotation speed Nm from falling into a high rotation state exceeding the allowable maximum rotation speed Nmmax. A gear ratio changing section 106 is provided, and the hybrid control section 104 is provided with a high rotation prevention means, that is, a high rotation prevention section 104a. The electronic control unit 100 further includes marginal rotational speed difference setting means, that is, marginal rotational speed difference setting section 108 , and state determination means, that is, state determination section 110 . State determination unit 110 determines whether or not MG2 rotation speed Nm has exceeded allowable maximum rotation speed Nmmax.

When the state determination unit 110 determines that the MG2 rotation speed Nm exceeds the allowable maximum rotation speed Nmmax, the high rotation prevention unit 104a reduces the engine torque Te so that the MG2 rotation speed Nm does not reach the MG2 upper limit rotation speed Nmlim. is output to hybrid control unit 104 . The hybrid control unit 104 reduces the engine torque Te by performing at least one torque reduction control such as lowering the opening of the electronic throttle valve 38 and retarding the ignition timing. Alternatively, the hybrid control unit 104 reduces the engine torque Te by performing fuel cut control to stop the fuel supply to the engine 12, for example.

Furthermore, when the state determination unit 110 determines that the MG2 rotation speed Nm exceeds the allowable maximum rotation speed Nmmax, the high rotation prevention unit 104a prevents the MG2 rotation speed Nm from reaching the MG2 upper limit rotation speed Nmlim. A command to generate power in the second rotary machine MG2, ie, a command to generate regenerative torque in the second rotary machine MG2, is output to the hybrid control unit 104.

The state determination unit 110 determines whether or not the vehicle state is a predetermined vehicle state in which the MG2 rotation speed Nm of the second rotary machine MG2 is likely to exceed the allowable maximum rotation speed Nmmax.

When driving on a slippery road surface, that is, on a slippery road surface, the driving wheels 14 spin easily to increase the output rotation speed No and the MG2 rotation speed Nm to a high rotation speed. A slippery road surface is a road surface on which the drive wheels 14 are likely to spin, and may be, for example, a low μ road, a wavy road, or an unpaved road.

The state determination unit 110 determines whether or not the vehicle state is the predetermined vehicle state based on whether or not the road on which the vehicle 10 is traveling is in a road surface state in which the drive wheels 14 are likely to spin. The state determination unit 110 detects, for example, the difference between the average wheel speed Nwd of the wheel speeds Nwdl and Nwdr of the drive wheels 14 and the average wheel speed Nws of the wheel speeds Nwsl and Nwsr of the driven wheels 14 in advance for determining that tire slip has occurred. Based on whether or not a predetermined slip determination threshold value is exceeded, it is determined whether or not the road surface of the vehicle 10 is in a state where the drive wheels 14 are likely to spin. Alternatively, the wheel slip ratio SR (=(Nwd−Nws)/Nwd), the rate of change of the wheel speeds Nwdl, Nwdr, Nwsl, Nwsr, the outside air temperature, the road surface temperature, the vehicle acceleration, etc. are used to determine whether the driving road of the vehicle 10 is the driving wheel. 14, it may be determined whether or not the vehicle is in a road surface condition in which slipping is likely to occur.

The transmission gear ratio changing unit 106 includes change condition determination means, that is, change condition satisfaction determination section 106a, first transmission gear ratio determination means, that is, first transmission ratio determination section 106b, and second transmission ratio determination means, that is, second transmission ratio determination section 106b. A section 106c and a margin determination means, that is, a margin determination section 106d are provided. When the change condition establishment determining unit 106a determines that the gear ratio changing condition CD for changing the gear ratio γat of the stepped transmission unit 60 is established, the gear ratio changing unit 106 determines the gear ratio by the first gear ratio determining unit 106b. The stepped transmission unit 60 performs shift control so that the first gear ratio γat1 determined by the second gear ratio determination unit 106c or the second gear ratio γat2 determined by the second gear ratio determination unit 106c. The gear ratio γat of the stepped transmission section 60 controlled using the gear shift map is forcibly changed. If the change condition establishment determining unit 106a determines that the gear ratio changing condition CD is not satisfied, the gear ratio changing unit 106 does not execute the gear shifting control in the stepped gear shifting unit 60, and the AT gear shifting control unit 102 , the gear ratio γat of the stepped transmission unit 60 controlled using the AT gear stage shift map is not changed.

Change condition establishment determination unit 106a determines that gear ratio change condition CD is established when preset first condition CD1 and preset second condition CD2 are met. The first condition CD1 is established, for example, when the state determination unit 110 determines that the vehicle state is the predetermined vehicle state. Further, the second condition CD2 is established, for example, when the actual rotational speed difference ΔN becomes equal to or less than the marginal rotational speed difference ΔNr set by the marginal rotational speed difference setting unit 108 (ΔN≦ΔNr).

Note that the actual rotation speed difference ΔN is the rotation speed difference (Nmmax−Nm1) between the allowable maximum rotation speed Nmmax [rpm] and the MG2 rotation speed Nm1 [rpm]. The MG2 rotation speed Nm1 is, for example, the MG2 rotation speed Nm detected by the MG2 rotation speed sensor 94 when the state determination unit 110 determines that the vehicle state is the predetermined vehicle state.

Further, when the state determining unit 110 determines that the vehicle state is the predetermined vehicle state, the marginal rotational speed difference setting unit 108 sets the marginal rotational speed difference ΔNr using the marginal rotational speed difference setting map shown in FIG. set. In the rotational speed margin setting map, the marginal rotational speed difference ΔNr increases as the margin between the MG2 rotational speed Nm and the maximum allowable rotational speed Nmmax while the vehicle is traveling is small, and the margin is large. It is set so that the margin rotational speed difference ΔNr becomes smaller as the number increases. Further, the margin can be represented by, for example, the coefficient of friction μ of the road surface while the vehicle is running. The lower the friction coefficient μ, the higher the output rotation speed No due to the idling of the drive wheels 14, and the MG2 rotation speed Nm tends to increase, so the margin becomes smaller. Since it is difficult for the rotation speed Nm to increase, the margin is increased. Further, the friction coefficient μ of the road surface may be represented by the wheel slip ratio SR. When the road surface friction coefficient μ is represented by the wheel slip ratio SR, the road surface friction coefficient μ decreases as the wheel slip ratio SR increases, and the road surface friction coefficient μ increases as the wheel slip ratio SR decreases. The friction coefficient μ of the road surface or the wheel slip ratio SR is calculated using, for example, the wheel speeds Nwdl, Nwdr, Nwsl, and Nwsr detected by the wheel speed sensors 91 in the state determination unit 110. .

Note that, in the marginal rotational speed difference setting map, based on the supercharging pressure Pchg detected by the supercharging pressure sensor 40 when the state determination unit 110 determines that the vehicle state is the predetermined vehicle state, for example One straight line is selected from among a plurality of straight lines including the first straight line LA1, the second straight line LA2, the third straight line LA3, etc. as part thereof, and the rotational speed margin ΔNr is set. The first straight line LA1, the second straight line LA2, and the third straight line LA3 represent some straight lines among the plurality of straight lines, and the other straight lines are omitted in the margin rotational speed difference setting map. Further, in the rotational speed margin setting map, the plurality of straight lines are arranged so that the marginal rotational speed difference ΔNr is set to a larger value as the detected supercharging pressure Pchg is higher. The first straight line LA1 is a straight line indicating a case where the detected supercharging pressure Pchg is relatively high and the responsiveness of the engine torque Te is relatively slow. The third straight line LA3 is a straight line indicating a case where the detected supercharging pressure Pchg is relatively low, for example zero, and the responsiveness of the engine torque Te is relatively fast. The second straight line LA2 indicates a case where the detected supercharging pressure Pchg is intermediate between the supercharging pressure Pchg for which the first straight line LA1 is selected and the supercharging pressure Pchg for which the third straight line LA3 is selected. Straight line. That is, as shown in the marginal rotational speed difference setting map, the marginal rotational speed difference setting unit 108 sets the marginal rotational speed difference ΔNr based on the detected supercharging pressure Pchg when the supercharging pressure Pchg is high compared to when the supercharging pressure Pchg is low. The larger the value is set, and the higher the detected supercharging pressure Pchg is, the larger the marginal rotation speed difference ΔNr is set.

When the change condition establishment determination unit 106a determines that the change condition change condition CD is established, the first gear ratio determination unit 106b increases the actual rotation speed difference ΔN more than the margin rotation speed difference ΔNr. The first gear ratio γat1 that reduces the MG2 rotation speed Nm, which is the rotation speed of the input rotary member of the unit 60, is selected from among a plurality of (four in this embodiment) gear ratios γat formed in the stepped transmission unit 60. determine one. That is, the first gear ratio determination unit 106b determines one AT gear stage of the first gear ratio γat1 from among a plurality of (four in this embodiment) AT gear stages formed by the stepped transmission unit 60. . Note that the first gear ratio γat1 is changed from the gear ratio γat of the stepped transmission portion 60 to the first gear ratio γat1, so that the MG2 rotation speed Nm, that is, the intermediate transmission member which is the input rotating member of the stepped transmission portion 60 70 is the gear ratio γat at which the rotational speed of 70 is lower than the first rotational speed (Nmmax−ΔNr) obtained by subtracting the marginal rotational speed difference ΔNr from the allowable maximum rotational speed Nmmax. Further, when there are a plurality of gear ratios γat at which the MG2 rotation speed Nm is lower than the first rotation speed (Nmmax−ΔNr) in the stepped transmission section 60, the first gear ratio determination section 106b selects the largest gear ratio γat. It is determined as the first gear ratio γat1. Note that the first gear ratio γat1 is a gear ratio γat that is smaller than the gear ratio γat formed in the stepped transmission section 60 when the gear ratio change condition CD is determined to be satisfied by the change condition satisfaction determining section 106a. be. That is, the AT gear stage of the first gear ratio γat1 is on the higher side than the AT gear stage formed in the stepped transmission section 60 when the change condition establishment determination section 106a determines that the gear ratio change condition CD is satisfied. is the AT gear stage.

When the first gear ratio determination unit 106b determines the first gear ratio γat1, the margin determination unit 106d changes the gear ratio γat of the stepped transmission unit 60 to the determined first gear ratio γat1. It is determined whether or not there is a sufficient margin between the rotation speed of other rotating elements and a predetermined upper limit rotation speed, for example, between the MG1 rotation speed Ng and the MG1 upper limit rotation speed Nglim. For example, when the gear ratio γat of the stepped transmission unit 60 is changed to the first gear ratio γat1, the margin determining unit 106d determines that the difference between the allowable maximum rotation speed Ngmax and the MG1 rotation speed Ng is a preset margin rotation speed. If it is larger than the speed difference ΔNg, it is determined that there is a sufficient margin between the MG1 rotation speed Ng and the MG1 upper limit rotation speed Nglim. The MG1 rotation speed Ng when the gear ratio is changed to the first gear ratio γat1 is estimated from the rotation speed (MG2 rotation speed Nm) of the input rotary member of the stepped transmission unit 60 when the gear ratio is changed to the first gear ratio γat1, for example. be done.

When the margin determination unit 106d determines that there is insufficient margin between the rotation speed of the other rotating element and the predetermined upper limit rotation speed, the second gear ratio determination unit 106c adjusts the MG2 rotation speed Nm and the allowable maximum rotation speed. Nmmax and the margin between the MG1 rotation speed Ng and the allowable maximum rotation speed Ngmax are equalized compared to changing to the first gear ratio γat1. One of a plurality of (four in this embodiment) gear ratios γat formed in the transmission unit 60 is determined. For example, if the margin determination unit 106d determines that there is not enough margin between the rotational speed of the other rotating element and the predetermined upper limit rotational speed, the second gear ratio determination unit 106c is formed by the stepped transmission unit 60. Among the plurality of gear ratios γat that are calculated, the gear ratio γat that is the second largest after the first gear ratio γat1 is determined as the second gear ratio γat2.

When the margin determining unit 106d determines that there is a sufficient margin between the rotational speed of the other rotating element and the predetermined upper limit rotational speed, the gear ratio changing unit 106 determines the The first gear ratio γat1 is selected as the target gear ratio γat_tgt, and the gear ratio γat of the stepped transmission portion 60 is executed so that the gear ratio γat of the stepped transmission portion 60 becomes the target gear ratio γat_tgt. is changed to the first gear ratio γat1.

Further, when the margin determining section 106d determines that there is not enough margin between the rotational speed of the other rotating element and the predetermined upper limit rotational speed, the gear ratio changing section 106 determines by the second gear ratio determining section 106c. The second gear ratio γat2 thus obtained is selected as the target gear ratio γat_tgt, and the gear ratio γat of the stepped gearbox 60 is controlled so that the gear ratio γat of the stepped gearbox 60 becomes the target gear ratio γat_tgt. The gear ratio γat of the portion 60 is changed to the second gear ratio γat2. The second gear ratio γat2 determined by the second gear ratio determining section 106c is formed by the stepped transmission section 60 when it is determined by the change condition establishment determination section 106a that the gear ratio change condition CD is satisfied. If the gear ratio γat is the same as the gear ratio γat, the gear ratio changer 106 does not execute gear shift control in the stepped gear shifter 60 . Further, when the gear ratio changing unit 106 is performing shift control in the stepped transmission unit 60, the hybrid control unit 104 does not change the engine operating point OPeng, that is, does not change the engine rotation speed Ne and the engine torque Te. , the engine 12 and the first rotary machine MG1 are controlled.

FIG. 15 is a flowchart for explaining the essential part of the control operation of the electronic control unit 100, and is a flowchart for explaining the control operation for suppressing the MG2 rotation speed Nm from falling into a high rotation state exceeding the allowable maximum rotation speed Nmmax. is. Also, FIG. 16 is a time chart when an example of the control operation shown in the flow chart of FIG. 15 is executed.

In FIG. 15, first, in step S10 corresponding to the functions of the change condition establishment determination unit 106a and the state determination unit 110 (hereinafter, the step is omitted), the road surface condition of the road surface of the vehicle 10 is such that the driving wheels 14 are likely to spin. For example, it is determined whether the vehicle 10 is traveling on a low μ road. If the determination in S10 is affirmative (at time t1 in FIG. 16), that is, if the road surface of the vehicle 10 is in a state where the driving wheels 14 are likely to spin, the function of the change condition determination section 106a is performed. S20 is executed. If the determination in S10 is negative, that is, if the road surface of the vehicle 10 is not in a state where the drive wheels 14 are likely to slip and the gear ratio change condition CD is not satisfied, the function of the gear ratio changer 106 is performed. S30 is executed. In S20, an actual rotational speed difference ΔN, which is the rotational speed difference between the allowable maximum rotational speed Nmmax and the MG2 rotational speed Nm1, is calculated. Next, S40 corresponding to the function of marginal rotational speed difference setting section 108 is executed. In S40, the rotational speed margin ΔNr is set using, for example, a rotational speed margin setting map shown in FIG. Next, S50 corresponding to the function of the change condition establishment determination unit 106a is executed. In S50, it is determined whether or not the actual rotational speed difference ΔN is greater than the marginal rotational speed difference ΔNr (ΔN>ΔNr). If the determination in S50 is affirmative, that is, if the actual rotational speed difference ΔN is not equal to or less than the marginal rotational speed difference ΔNr and the gear ratio change condition CD is not satisfied, S30 is executed. If the determination in S50 is negative, that is, if the actual rotational speed difference ΔN is equal to or less than the marginal rotational speed difference ΔNr and the gear ratio changing condition CD is satisfied, S60 corresponding to the function of the first gear ratio determining section 106b is executed. executed. In S30, the gear ratio γat of the stepped transmission section 60 is not changed.

In S60, a first gear ratio γat1 that increases the actual rotational speed difference ΔN more than the marginal rotational speed difference ΔNr is determined from a plurality of gear ratios γat formed in the stepped transmission section 60. Next, S70 corresponding to the function of the margin determination unit 106d is executed. In S70, when the gear ratio γat of the stepped transmission unit 60 is changed so as to become the first gear ratio γat1 determined in S60, a sufficient amount of change is made between the rotation speed of the other rotating element and the predetermined upper limit rotation speed. It is determined whether or not there is a margin, that is, whether or not there is a sufficient margin in the rotational speeds of other rotating elements. If the determination in S70 is affirmative, that is, if there is no sufficient margin between the rotation speed of the other rotating element and the predetermined upper limit rotation speed, the functions of the second gear ratio determining section 106c and the gear ratio changing section 106 S80 corresponding to is executed. If the determination in S70 is negative, that is, if there is a sufficient margin between the rotation speed of the other rotating element and the predetermined upper limit rotation speed, S90 corresponding to the function of gear ratio changing section 106 is executed. . In S80, the next largest gear ratio γat after the first gear ratio γat1 determined in S60 is determined as the second gear ratio γat2, and the second gear ratio γat2 is selected as the target gear ratio γat_tgt. In S90, the first gear ratio γat1 determined in S60 is selected as the target gear ratio γat_tgt. Next, in S100 corresponding to the function of the gear ratio changing unit 106, gear shift control is executed in the stepped gear shift unit 60 so as to achieve the target gear ratio γat_tgt selected in S80 or S90. The gear ratio γat is changed. In the time chart of FIG. 16, at time t2, the actual rotational speed difference ΔN becomes equal to or less than the marginal rotational speed difference ΔNr, and the gear ratio change condition CD is established, and the actual rotational speed difference ΔN is higher than the marginal rotational speed difference ΔNr. It shows the point in time when shift control (shift) is started in the stepped transmission unit 60 in order to increase the gear ratio γat. Further, the time t3 indicates the time when the speed change control (speed change) in the stepped speed change portion 60 is completed. In this embodiment, when speed change control is executed in the stepped transmission portion 60 and the gear ratio γat of the stepped transmission portion 60 is changed, as shown in the time chart of FIG. MG2 rotation speed Nm, which is the rotation speed of , decreases, and the actual rotation speed difference ΔN increases.

As described above, according to the present embodiment, the MG2 rotation speed Nm exceeds the allowable maximum rotation speed Nmmax at which a margin for the MG2 rotation speed Nm is secured with respect to the MG2 upper limit rotation speed Nmlim of the second rotary machine MG2. In this case, a high rotation prevention unit 104a that reduces the engine torque Te so that the MG2 rotation speed Nm does not reach the MG2 upper limit rotation speed Nmlim, and a rotation speed difference between the allowable maximum rotation speed Nmmax and the MG2 rotation speed Nm. a gear ratio changing unit 106 that changes the gear ratio γat of the stepped transmission unit 60 so as to increase the actual rotational speed difference ΔN when the rotational speed difference ΔN becomes equal to or less than the marginal rotational speed difference ΔNr. Therefore, when the actual rotational speed difference ΔN becomes equal to or less than the marginal rotational speed difference ΔNr, the gear ratio γat of the stepped transmission section 60 is changed so as to increase the actual rotational speed difference ΔN. The difference between the speed Nmmax and the MG2 rotational speed Nm is suppressed from becoming equal to or less than the marginal rotational speed difference ΔNr. This ensures a relatively sufficient margin in the difference between the allowable maximum rotation speed Nmmax and the MG2 rotation speed Nm, thereby preventing the MG2 rotation speed Nm from falling into a high rotation state exceeding the allowable maximum rotation speed Nmmax. can be done.

Further, according to the present embodiment, based on the supercharging pressure Pchg by the supercharger 18, when the supercharging pressure Pchg is high, the marginal rotational speed difference ΔNr is set to a larger value than when the supercharging pressure Pchg is low. 108. Therefore, when the supercharging pressure Pchg is high, the rotational speed margin ΔNr is set to a larger value than when the supercharging pressure Pchg is low. It becomes difficult for the difference to be less than or equal to ΔNr. As a result, when the supercharging pressure Pchg is low, it becomes more difficult to change the gear ratio γat of the stepped transmission portion 60 than when it is high. While suppressing, it is possible to suitably suppress the MG2 rotation speed Nm from falling into a high rotation state exceeding the allowable maximum rotation speed Nmmax.

Further, according to the present embodiment, the marginal rotational speed difference setting unit 108 sets the marginal rotational speed difference ΔNr to a larger value as the supercharging pressure Pchg is higher. It is possible to suppress falling into a high rotation state exceeding Nmmax.

Further, according to the present embodiment, the vehicle state is provided with the state determination unit 110 for determining whether or not the vehicle state is a predetermined vehicle state in which the MG2 rotation speed Nm is likely to exceed the allowable maximum rotation speed Nmmax, and the gear ratio changing unit 106 , when the vehicle state is determined to be the predetermined vehicle state and the actual rotational speed difference ΔN becomes equal to or less than the marginal rotational speed difference ΔNr, the stepped transmission portion 60 is shifted so as to increase the actual rotational speed difference ΔN. Change the ratio γat. Therefore, when the vehicle state is determined to be the predetermined vehicle state and the actual rotational speed difference ΔN becomes equal to or less than the marginal rotational speed difference ΔNr, the gear ratio changing unit 106 changes the gear ratio γat of the stepped transmission unit 60. is changed, for example, when the actual rotation speed difference ΔN becomes equal to or less than the allowance rotation speed difference ΔNr, the gear ratio γat of the stepped transmission portion 60 is changed excessively. It is possible to suppress the change of the gear ratio γat.

Further, according to the present embodiment, the state determination unit 110 determines that the vehicle state is the predetermined vehicle state based on whether or not the road surface of the vehicle 10 is in a state where the driving wheels 14 are likely to spin. Determine whether or not Therefore, when the vehicle 10 is traveling on a road surface on which the drive wheels 14 are likely to spin, it is possible to prevent the MG2 rotation speed Nm from falling into a high rotation state exceeding the allowable maximum rotation speed Nmmax.

Another embodiment of the present invention will now be described. In the following description, the same reference numerals are given to the parts common to the embodiments, and the description thereof is omitted.

In this embodiment, a vehicle 200 as shown in FIG. 17 is illustrated, which is different from the vehicle 10 shown in the first embodiment. FIG. 17 is a diagram illustrating a schematic configuration of vehicle 200 to which the present invention is applied. In FIG. 17 , vehicle 200 is a hybrid vehicle including engine 202 , rotary machine MG, power transmission device 204 and drive wheels 206 .

The engine 202 has the same configuration as the engine 12 shown in the first embodiment. The engine 202 is controlled by an electronic control device (control device) 218, which will be described later. Te is controlled.

The rotating machine MG is a rotating electric machine having a function as an electric motor and a function as a generator, and is a so-called motor generator. The rotating machine MG is a rotating machine that is coupled to the driving wheels 206 via the power transmission device 204 so as to be able to transmit power. Rotating machine MG is connected to a battery 212 as a power storage device provided in vehicle 200 via an inverter 210 provided in vehicle 200 . In the rotary machine MG, the MG torque Tmg, which is the output torque of the rotary machine MG, is controlled by controlling the inverter 210 by an electronic control unit 218, which will be described later.

The power transmission device 204 includes a clutch K0, an automatic transmission (transmission) 214, and the like. An input rotary member of the automatic transmission 214 is coupled to the engine 202 via the clutch K0 and directly coupled to the rotary machine MG. In the power transmission device 204, the power of the engine 202 is transmitted to the driving wheels 206 through the clutch K0, the automatic transmission 214, etc., and the power of the rotary machine MG is transmitted to the driving wheels 206 through the automatic transmission 214, etc. be. Engine 202 and rotary machine MG are power sources for running vehicle 200 , which are connected to drive wheels 206 so as to be able to transmit power. Automatic transmission 214 is provided in a power transmission path between rotary machine MG and driving wheels 206 .

Clutch K0 is a hydraulic friction engagement device that connects and disconnects a power transmission path between engine 202 and driving wheels 206. As shown in FIG. The automatic transmission 214 is, for example, a known planetary gear type automatic transmission including a plurality of sets of planetary gears and a plurality of engaging devices, like the stepped transmission 60 shown in the first embodiment. . In the automatic transmission 214, a hydraulic control circuit 216 provided in the vehicle 200, which is driven by an electronic control unit 218, which will be described later, adjusts and controls the engagement hydraulic pressures of the plurality of engagement devices, thereby forming a plurality of gears. A gear stage of any of the stages is formed.

In vehicle 200, with clutch K0 disengaged and engine 202 stopped, electric power from battery 212 is used to enable motor running using only rotating machine MG as a power source for running. Further, in the vehicle 200, the engine 202 is operated in a state where the clutch K0 is engaged, and hybrid running is possible using at least the engine 202 as a power source for running.

Vehicle 200 further includes an electronic control unit 218 as a controller including control units of vehicle 200 related to control of engine 202, rotary machine MG, and the like. The electronic control unit 218 has the same configuration as the electronic control unit 100 shown in the first embodiment. Various signals similar to those supplied to the electronic control unit 100 are supplied to the electronic control unit 218 . The electronic control unit 218 outputs various command signals similar to those output by the electronic control unit 100 . The electronic control unit 218 has functions equivalent to the functions of the AT transmission control unit 102, the hybrid control unit 104, the gear ratio change unit 106, the marginal rotational speed difference setting unit 108, and the state determination unit 110 provided in the electronic control unit 100. have. The electronic control unit 218 suppresses the rotation speed of the rotating machine MG from falling into a high rotation state exceeding the allowable maximum rotation speed, which is the same as realized by the electronic control unit 100 as shown in the first embodiment. A control function can be realized.

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

For example, in the above-described first embodiment, the state determination unit 110 determines that the vehicle state is the predetermined vehicle state based on whether or not the road surface of the vehicle 10 is in a state where the driving wheels 14 are likely to spin. was deciding whether or not For example, the state determination unit 110 may determine whether or not the vehicle state is the predetermined vehicle state based on whether or not the second rotary machine MG2 is subject to a predetermined output limitation. good. Note that the predetermined output limit is an output limit that prevents the second rotating machine MG2 from properly generating power, for example, when performing high rotation prevention control by the second rotating machine MG2. The output limitation that prevents the second rotating machine MG2 from properly generating power includes, for example, a state in which the second rotating machine MG2 is at a high temperature or a low temperature such that the MG2 temperature THm is outside a predetermined normal temperature range THmra, or , the battery 54 is assumed to be at a high temperature or a low temperature such that the battery temperature THbat is outside the predetermined normal temperature range THbatra. The predetermined normal temperature range THmra is the normal use range of the second rotating machine MG2, and is a predetermined temperature range of the second rotating machine MG2 in which the output of the second rotating machine MG2 is not reduced due to the MG2 temperature THm. . A predetermined normal temperature range THbatra is a normal use range of the battery 54, and is a predetermined temperature range of the battery 54 in which the chargeable/dischargeable electric power Win, Wout is not reduced due to the battery temperature THbat. According to the electronic control unit 100 including the state determination unit 110, the MG2 rotation speed Nm exceeds the allowable maximum rotation speed Nmmax when the second rotary machine MG2 is in the state of being subject to the predetermined output limitation. It is possible to suitably suppress falling into a high rotation state. It should be noted that when state determination unit 110 determines whether or not the vehicle state is the predetermined vehicle state based on whether or not the second rotary machine MG2 is in the state in which the predetermined output is restricted. , when setting the marginal rotational speed difference ΔNr, instead of the marginal rotational speed difference setting map shown in FIG. A marginal rotational speed difference setting map may be used that is set such that the marginal rotational speed difference ΔNr increases as the temperature deviates from the predetermined normal temperature range THbatra.

Further, in the first embodiment described above, the state determination unit 110 determines that the vehicle state is the predetermined vehicle state based on whether or not the road surface of the vehicle 10 is in a state where the driving wheels 14 are likely to spin. was deciding whether or not For example, the state determination unit 110 determines the condition that the road surface of the vehicle 10 is in a state where the driving wheels 14 are likely to spin, and the condition that the second rotary machine MG2 is subject to the predetermined output limitation. When at least one condition is established, it may be determined that the vehicle state is the predetermined vehicle state.

Further, in the change condition establishment determining section 106a of the first embodiment described above, the gear ratio change condition CD is established when both the first condition CD1 and the second condition CD2 are established. However, the transmission gear ratio change condition CD may be established even when the second condition CD2 is established. That is, the gear ratio change condition CD is established when the actual rotational speed difference ΔN becomes equal to or less than the marginal rotational speed difference ΔNr, regardless of whether the vehicle state is the predetermined vehicle state or not. can be

Further, in the marginal rotational speed difference setting unit 108 of the first embodiment described above, the marginal rotational speed difference ΔNr was appropriately set using, for example, the marginal rotational speed difference setting map shown in FIG. One margin rotational speed difference ΔNr may be used all the time.

Further, in the margin determination unit 106d of the first embodiment described above, the MG1 rotation speed Ng is used as an example of rotation speeds of other rotating elements. For example, in the margin determination unit 106d, instead of the MG1 rotational speed Ng, the rotational speed of another rotational element such as the relative rotational speed Np2 of the second pinion P2 may be used.

The gear ratio changing section 106 of the first embodiment described above changes the gear ratio γat of the stepped transmission section 60 in order to prevent the MG2 rotation speed Nm from falling into a high rotation state exceeding the allowable maximum rotation speed Nmmax. rice field. For example, the transmission gear ratio changing unit 106, in order to suppress the MG1 rotation speed Ng from falling into a high rotation state exceeding the allowable maximum rotation speed Ngmax, for example, the state where the engine operating point OPeng is not changed, that is, the engine rotation speed Ne and the engine torque The gear ratio γat of the stepped transmission section 60 may be changed by downshifting the stepped transmission section 60 without changing Te. Further, for example, the transmission gear ratio changing unit 106, in order to prevent the relative rotation speed Np2 of the second pinion P2 from falling into a high rotation state exceeding the allowable maximum rotation speed Np2max, for example, maintains a state in which the engine operating point OPeng is not changed, i.e., The gear ratio γat of the stepped transmission section 60 may be changed by upshifting the stepped transmission section 60 without changing the engine rotation speed Ne and the engine torque Te. The allowable maximum rotational speed Np2max is the relative rotational speed Np2 of the second pinion P2 set lower than the pinion upper limit relative rotational speed Np2lim by a margin δ. The margin δ is a margin of the relative rotation speed Np2 of the second pinion P2, which is predetermined so that the relative rotation speed Np2 of the second pinion P2 does not exceed the pinion upper limit relative rotation speed Np2lim.

Further, in the above-described first embodiment, the one-way clutch F0 was exemplified as a locking mechanism capable of fixing the carrier CA0 so that it cannot rotate, but the present invention is not limited to this aspect. This lock mechanism selectively connects the connecting shaft 68 and the case 56, for example, a mesh type clutch, a hydraulic friction engagement device such as a clutch or a brake, a dry engagement device, an electromagnetic friction engagement device, a magnetic powder It may be an engaging device such as a type clutch. Alternatively, the vehicle 10 does not necessarily have to include the one-way clutch F0.

Further, in the first embodiment described above, the stepped transmission portion 60 was exemplified as the automatic transmission (transmission) provided in the power transmission path between the second rotary machine MG2 and the drive wheels 14. Not exclusively. This automatic transmission is, for example, a synchronous mesh parallel twin shaft automatic transmission, a known DCT (Dual Clutch Transmission) which is a synchronous mesh parallel twin shaft automatic transmission having two input shafts, a known belt It may be an automatic transmission such as a continuously variable transmission of the type.

Further, in the first embodiment described above, in addition to the exhaust turbine type supercharger 18, a mechanical pump type supercharger that is rotationally driven by an engine or an electric motor may be provided.

It should be noted that what has been described above is just one embodiment, and the present invention can be implemented in aspects with various modifications and improvements based on the knowledge of those skilled in the art.

10, 200: Vehicle (hybrid vehicle)
12, 202: Engine 14, 206: Driving wheel 18: Supercharger 60: Stepped transmission (transmission)
100, 218: electronic controller (controller)
104a: high rotation prevention unit 106: transmission gear ratio change unit 106a: change condition establishment determination unit 108: margin rotational speed difference setting unit 110: state determination unit 214: automatic transmission (transmission)
MG: rotating machine MG2: second rotating machine (rotating machine)
Nm: MG2 rotation speed (rotation speed)
Nmlim: MG2 upper limit rotation speed (predetermined upper limit rotation speed)
Nmmax: Allowable maximum rotational speed Pchg: Boost pressure Te: Engine torque (output torque)
γat: gear ratio ΔN: actual rotation speed difference (rotational speed difference)
ΔNr: Margin rotational speed difference

Claims (5)

An engine with a supercharger that functions as a power source for running, a rotating machine that is connected to drive wheels so that power can be transmitted, and a transmission that is provided in a power transmission path between the rotating machine and the drive wheels. A control device for a hybrid vehicle comprising
When the rotational speed of the rotating machine exceeds the allowable maximum rotational speed at which a margin of the rotational speed of the rotating machine is secured with respect to the predetermined upper limit rotational speed of the rotating machine, the rotational speed of the rotating machine exceeds the above-mentioned a high rotation prevention unit that reduces the output torque of the engine so that it does not reach a predetermined upper limit rotation speed;
When the rotational speed difference between the allowable maximum rotational speed and the rotational speed of the rotating machine becomes equal to or less than a set marginal rotational speed difference, the gear ratio of the transmission is increased so as to increase the rotational speed difference. a gear ratio changing unit to be changed;
a marginal rotational speed difference setting unit that sets the marginal rotational speed difference to a larger value when the supercharging pressure is high than when the supercharging pressure is low, based on the supercharging pressure by the supercharger. Vehicle controller. The control device for a hybrid vehicle according to claim 1 , wherein the marginal rotational speed difference setting unit sets the marginal rotational speed difference to a larger value as the supercharging pressure is higher. An engine with a supercharger that functions as a power source for running, a rotating machine that is connected to drive wheels so that power can be transmitted, and a transmission that is provided in a power transmission path between the rotating machine and the drive wheels. A control device for a hybrid vehicle comprising
When the rotational speed of the rotating machine exceeds the allowable maximum rotational speed at which a margin of the rotational speed of the rotating machine is secured with respect to the predetermined upper limit rotational speed of the rotating machine, the rotational speed of the rotating machine exceeds the above-mentioned a high rotation prevention unit that reduces the output torque of the engine so that it does not reach a predetermined upper limit rotation speed;
When the rotational speed difference between the allowable maximum rotational speed and the rotational speed of the rotating machine becomes equal to or less than a set marginal rotational speed difference, the gear ratio of the transmission is increased so as to increase the rotational speed difference. a gear ratio changing unit to be changed;
a state determination unit that determines whether or not the vehicle state is a predetermined vehicle state in which the rotation speed of the rotating machine easily exceeds the maximum allowable rotation speed ,
The transmission gear ratio changing unit increases the rotational speed difference when it is determined that the vehicle state is the predetermined vehicle state and the rotational speed difference becomes equal to or less than the marginal rotational speed difference. A control device for a hybrid vehicle, characterized in that it changes the gear ratio of the The state determination unit determines whether or not the vehicle state is the predetermined vehicle state based on whether or not the road surface of the hybrid vehicle is in a state where the driving wheels are likely to spin. 4. The hybrid vehicle control device according to claim 3 . When the rotation speed of the rotating machine exceeds the allowable maximum rotation speed, the high rotation prevention unit further prevents the rotation speed of the rotating machine from reaching the predetermined upper limit rotation speed. to generate electricity,
The state determination unit determines whether or not the vehicle state is the predetermined vehicle state based on whether or not the rotary machine is subject to a predetermined output limitation. 5. The hybrid vehicle control device according to item 3 or 4 .

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