Hybrid vehicle control device

Abstract

To provide a control device of a hybrid vehicle that can suppress delay in completion of starting control while suppressing delay in completion of downshift control even when an inertia phase in the downshift control is started before synchronization of a frictional engagement device in the starting control of an internal combustion engine is completed.SOLUTION: In executing starting control of an engine 12 and downshift control of an automatic transmission 24 are executed around the same time, an electronic control device 90 delays, when it is not sensed that an inertia phase in the downshift control is started before synchronization of a K0 clutch 20 is completed, starting of the inertia phase until the synchronization of the K0 clutch 20 in the starting control is completed (a); and when it is sensed that the inertia phase is started before the synchronization of the K0 clutch 20 is completed, makes the inertia phase progress and boosts K0 clutch-indication pressure Pk0 for engagement of the K0 clutch 20 in the starting control higher than when it is not sensed that the inertial phase is started (b).SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a control device for a hybrid vehicle that includes an internal combustion engine and an electric motor as driving force sources for driving the vehicle, a friction engagement device that connects and disconnects the power transmission between the internal combustion engine and the electric motor, and an automatic transmission that changes the speed of the driving force output from the driving force source for driving the vehicle. [Background technology]

[0002] In a hybrid vehicle equipped with an internal combustion engine and an electric motor as a driving force source for traveling, a friction engagement device for connecting and disconnecting the power transmission between the internal combustion engine and the electric motor, and an automatic transmission for shifting the driving force output from the driving force source for traveling, when start control of the internal combustion engine and downshift control of the automatic transmission are executed simultaneously, a method is known in which the start control and downshift control are executed simultaneously after it is detected that the rotation speed of the internal combustion engine has reached a predetermined rotation speed or higher. For example, one such method is described in Patent Document 1. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5914520 Summary of the Invention [Problem to be solved by the invention]

[0004] If the inertia phase in the downshift control is started before the rotation speed of the internal combustion engine reaches a predetermined rotation speed or higher, it is preferable to control the downshift control so as to complete it early, but in the method described in Patent Document 1, the downshift control cannot proceed until the rotation speed of the internal combustion engine reaches a predetermined rotation speed or higher, and there is a risk that drivability that meets the driver's needs will not be realized. On the other hand, a method of proceeding with the downshift control before the rotation speed of the internal combustion engine reaches a predetermined rotation speed or higher is also conceivable, but in such a method, the rotation speed of the automatic transmission side (= electric motor side) of the friction engagement device increases due to the progression of the inertia phase in the downshift control, which delays the completion of synchronization of the friction engagement device, i.e., delays the completion of the start control of the internal combustion engine.

[0005] The present invention has been made against the background of the above circumstances, and its purpose is to provide a control device for a hybrid vehicle that can suppress delays in the completion of start-up control while suppressing delays in the completion of downshift control, even if the inertia phase of downshift control is initiated before synchronization of the friction engagement devices in the start-up control of the internal combustion engine is completed. [Means for solving the problem]

[0006] The gist of the present invention is a control device for a hybrid vehicle including an internal combustion engine and an electric motor as a driving force source for driving a vehicle, a hydraulic friction engagement device that disconnects power transmission between the internal combustion engine and the electric motor, and an automatic transmission that changes the speed of the driving force output from the driving force source for driving a vehicle, wherein (A) when a start-up control of the internal combustion engine and a downshift control of the automatic transmission are executed simultaneously, (a-1) if it is not detected that an inertia phase in the downshift control has started before synchronization of the friction engagement device is completed, the start of the inertia phase is delayed until synchronization of the friction engagement device in the start-up control is completed, and (a-2) if it is detected that the inertia phase has started before synchronization of the friction engagement device is completed, the inertia phase is advanced, and the control pressure for engaging the friction engagement device in the start-up control is increased compared to when the start of the inertia phase is not detected. Effect of the Invention

[0007] According to the control device for a hybrid vehicle of the present invention, (A) when the start control of the internal combustion engine and the downshift control of the automatic transmission are executed at the same time, (a-1) if the start of the inertia phase in the downshift control is not detected before the synchronization of the frictional engagement device is completed, the start of the inertia phase is delayed until the synchronization of the frictional engagement device in the start control is completed, and (a-2) if the start of the inertia phase is detected before the synchronization of the frictional engagement device is completed, the inertia phase is advanced, and the control pressure for engaging the frictional engagement device in the start control is increased compared to when the start of the inertia phase is not detected. In this way, if the start of the inertia phase in the downshift control of the automatic transmission is detected before the synchronization of the frictional engagement device is completed, the start control of the internal combustion engine is advanced and the inertia phase is advanced. Also, the control pressure for engaging the frictional engagement device in the start control is increased compared to when the start of the inertia phase is not detected. By advancing the inertia phase in the downshift control, the delay in the completion of the downshift control is suppressed, and by increasing the control pressure for engaging the friction engagement devices in the start control, the delay in the completion of synchronization of the friction engagement devices (i.e., the delay in the completion of the start control of the internal combustion engine) is suppressed. This makes it easier to achieve drivability that meets the driver's needs. [Brief description of the drawings]

[0008] [Figure 1] 1 is a schematic configuration diagram of a hybrid vehicle equipped with an electronic control device according to an embodiment of the present invention, and is also a functional block diagram showing essential parts of control functions for various controls in the hybrid vehicle. [Diagram 2] 2 is an example of a flowchart illustrating a control operation of the electronic control device shown in FIG. 1. [Diagram 3] This is a time chart in which the flowchart of FIG. 2 is executed, and is an example of a case in which the start of the inertia phase in the downshift control is not detected before synchronization of the K0 clutch is completed. [Figure 4] 3 is a time chart showing the execution of the flowchart of FIG. 2, and is an example of a case where the start of the inertia phase in the downshift control is detected before synchronization of the K0 clutch is completed. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that in the following embodiments, the drawings are appropriately simplified or modified, and the dimensional ratios and shapes of the various parts are not necessarily drawn accurately. EXAMPLES

[0010] This is a schematic configuration diagram of a hybrid vehicle 10 (hereinafter simply referred to as "vehicle 10") equipped with an electronic control device 90 according to an embodiment of the present invention, and is also a functional block diagram showing the main control functions for various controls in vehicle 10.

[0011] The vehicle 10 includes an engine 12 and an electric motor MG, which are driving power sources for traveling, and a power transmission device 16 provided in a power transmission path PT between the engine 12 and driving wheels 14. The vehicle 10 is a hybrid vehicle.

[0012] The engine 12 is a well-known internal combustion engine. An electronic control device 90 (described later) controls an engine control device 50 including a throttle actuator, a fuel injection device, an ignition device, and the like provided in the vehicle 10, thereby controlling an engine torque Te [Nm] that is an output torque of the engine 12. The engine 12 corresponds to the "internal combustion engine" in the present invention.

[0013] The power transmission device 16 includes, in order from the engine 12 side, an engine connecting shaft 34, a K0 clutch 20, an electric motor connecting shaft 36, a torque converter 22, a transmission input shaft 38 which is an input rotating member of the automatic transmission 24, the automatic transmission 24, and the like, housed within a case 18 which is a non-rotating member attached to the vehicle body. The power transmission device 16 also includes a propeller shaft 28 which is connected to a transmission output shaft 26 which is an output rotating member of the automatic transmission 24, a differential gear 30 which is connected to the propeller shaft 28, a pair of drive shafts 32 which are connected to the differential gear 30, and the like.

[0014] The engine connecting shaft 34 is a member that connects the engine 12 and the K0 clutch 20.

[0015] The K0 clutch 20 is disposed between the engine 12 and the electric motor MG in the power transmission path PT, and is a clutch that connects and disconnects the power transmission between the engine 12 and the electric motor MG. The electric motor connecting shaft 36 connects the K0 clutch 20 and the torque converter 22. The K0 clutch 20 is a hydraulic friction engagement device constituted by, for example, a multi-plate or single-plate clutch. The K0 clutch 20 changes the K0 torque Tk0 [Nm], which is the transmission torque capacity of the K0 clutch 20 (the engagement force of the K0 clutch 20), by the adjusted K0 oil pressure PRk0 [Pa] supplied from the hydraulic control circuit 56 to a hydraulic actuator that controls the connection and disconnection state of the K0 clutch 20. As a result, the K0 clutch 20 is switched between an operating state, i.e., a connection and disconnection state, such as a fully engaged state, a half-engaged state (=slip engagement state), and a released state. The command pressure of the K0 oil pressure PRk0 is referred to as a "K0 clutch command pressure Pk0 [Pa]." The K0 clutch command pressure Pk0 is a hydraulic command value that controls the engagement / disengagement state of the K0 clutch 20, and is a hydraulic command value that engages the K0 clutch 20 during engine start control. When the K0 clutch 20 is in a fully engaged or partially engaged state, the K0 clutch command pressure Pk0 is increased to increase the K0 torque Tk0. The K0 clutch 20 corresponds to the "friction engagement device" in this invention. The K0 clutch command pressure Pk0 corresponds to the "control pressure" in this invention.

[0016] The torque converter 22 is a well-known torque converter. The torque converter 22 includes a pump wheel 22a connected to the electric motor connecting shaft 36, a turbine wheel 22b connected to the transmission input shaft 38, and a lock-up clutch 40 that directly connects the pump wheel 22a and the turbine wheel 22b. The torque converter 22 is a fluid-type power transmission device that can transmit the driving force for traveling of the driving force source for traveling (the engine 12, the electric motor MG) from the electric motor connecting shaft 36 to the transmission input shaft 38 via a fluid.

[0017] The vehicle 10 includes the MOP 58 which is a mechanical oil pump, the EOP 60 which is an electric oil pump, a pump motor 62, etc. The MOP 58 is connected to the pump impeller 22a, and is rotated by a driving power source for traveling (the engine 12, the electric motor MG) to discharge hydraulic oil OIL used in the power transmission device 16. The pump motor 62 is a motor dedicated to the EOP for rotating the EOP 60. The EOP 60 is rotated by the pump motor 62 to discharge hydraulic oil OIL. The hydraulic oil OIL discharged by the MOP 58 and the EOP 60 is supplied to the hydraulic control circuit 56.

[0018] The electric motor MG is a rotating electric machine having a function as an electric motor that generates mechanical power from electric power and a function as a generator that generates electric power from mechanical power, and is a so-called motor generator. In this specification, power is synonymous with driving force, torque, and force unless otherwise specified. The electric motor MG is connected to a battery 54 provided in the vehicle 10 via an inverter 52 described later. The battery 54 is an electricity storage device that supplies and receives electric power to the electric motor MG. The electric motor MG controls the inverter 52 by an electronic control device 90 described later, thereby controlling the electric motor torque Tmg [Nm], which is the output torque of the electric motor MG.

[0019] The electric motor MG is connected to the electric motor connecting shaft 36 in the case 18 so as to be capable of transmitting power. That is, the electric motor MG is connected to the power transmission path PT between the K0 clutch 20 and the torque converter 22 so as to be capable of transmitting power.

[0020] The automatic transmission 24 is a known planetary gear type automatic transmission disposed between the torque converter 22 and the drive wheels 14 in the power transmission path PT, and includes, for example, one or more planetary gear sets (not shown) and a plurality of gear shift engagement devices CB. The automatic transmission 24 changes the speed of the driving force output from the driving force source for traveling and outputs it to the drive wheels 14. The gear shift engagement devices CB are, for example, known hydraulic friction engagement devices. The gear shift engagement devices CB have a CB torque Tcb [Nm], which is a transmission torque capacity of the gear shift engagement devices CB, changed by the regulated CB hydraulic pressure PRcb [Pa] supplied from the hydraulic control circuit 56 to a hydraulic actuator that controls the engagement and disengagement state of the gear shift engagement devices CB. As a result, the gear shift engagement devices CB are switched between engagement and disengagement states such as a fully engaged state, a half-engaged state, and a released state.

[0021] The automatic transmission 24 is a stepped transmission in which one of a plurality of gear stages (also called gear stages) with different speed ratios (also called gear ratios) γat (=AT input rotation speed Ni [rpm] / AT output rotation speed No [rpm]) is formed by engaging one of the engagement devices for shifting CB. The larger the speed ratio γat, the lower the gear stage, and the smaller the speed ratio γat, the higher the gear stage. The automatic transmission 24 switches the formed gear stage by switching the connection and disconnection state of a specific engagement device, which is an engagement device involved in the shifting of the automatic transmission 24, among the engagement devices for shifting CB, according to the driver's accelerator operation, the vehicle speed V [km / h], etc., by an electronic control device 90 described later. The AT input rotation speed Ni is the rotation speed of the transmission input shaft 38, and is the input rotation speed of the automatic transmission 24. The AT input rotation speed Ni is the same value as the turbine rotation speed Nt [rpm], which is the output rotation speed of the torque converter 22. The AT output rotation speed No is the rotation speed of the transmission output shaft 26 , and is the output rotation speed of the automatic transmission 24 .

[0022] For example, in the shift control of the automatic transmission 24 (hereinafter simply referred to as "shift control"), a shift is performed by switching one of the shift engagement devices CB between a fully engaged state and a released state, that is, a so-called clutch-to-clutch shift is performed. Here, in the clutch-to-clutch shift, the shift engagement device CB that is switched from a released state to a fully engaged state is referred to as an "engagement side engagement device CBcon," and the shift engagement device CB that is switched from a fully engaged state to a released state is referred to as a "release side engagement device CBdis." In addition, the command pressure of the CB hydraulic pressure PRcb supplied to the hydraulic actuator that controls the engagement / disengagement state of the engagement side engagement device CBcon is referred to as an "engagement side command pressure Pcon [Pa]," and the command pressure of the CB hydraulic pressure PRcb supplied to the hydraulic actuator that controls the engagement / disengagement state of the release side engagement device CBdis is referred to as a "release side command pressure Pdis [Pa]."

[0023] The shift control includes downshift control and upshift control. The downshift control is a shift control in which the automatic transmission 24 is shifted to a lower gear, and the upshift control is a shift control in which the automatic transmission 24 is shifted to a higher gear.

[0024] The hydraulic control circuit 56 generates a constant line pressure PL [Pa] using a primary regulator valve (not shown) with the hydraulic oil OIL supplied from the MOP 58 and the EOP 60 as the source pressure. The line pressure PL is set to a hydraulic pressure according to the input torque of the automatic transmission 24, etc. The hydraulic control circuit 56 also supplies various hydraulic pressures, adjusted using the line pressure PL as the source pressure, to each required part in the case 18.

[0025] For example, a K0 solenoid valve SC for controlling the connection and disconnection of the K0 clutch 20, and four gear shift solenoid valves SL1 to SL4 for controlling gear shifts (hereinafter, when no particular distinction is made, they will be referred to as "gear shift solenoid valves SL") are provided within the hydraulic control circuit 56. The K0 solenoid valve SC and the gear shift solenoid valves SL are, for example, well-known linear solenoid valves.

[0026] The drive current of the K0 solenoid valve SC is controlled to adjust the K0 hydraulic pressure PRk0, thereby controlling the engagement and disengagement of the K0 clutch 20. For example, the K0 clutch 20 is put into a released state by preventing the drive current from flowing through the K0 solenoid valve SC, and the K0 clutch 20 is put into a fully engaged state or a half-engaged state by controlling the current value of the drive current of the K0 solenoid valve SC.

[0027] By controlling each drive current of the shift solenoid valves SL, the CB hydraulic pressure PRcb is adjusted, and the engagement and disengagement states of the shift solenoid valves SL are controlled. As a result, the automatic transmission 24 is placed in a neutral state or a gear stage with a desired gear ratio γat is formed according to the engagement and disengagement state of a predetermined engagement device among the shift engagement devices CB. The shift engagement devices CB are, for example, wet-type multi-plate hydraulic friction engagement devices such as brakes and clutches.

[0028] In the power transmission device 16, when the K0 clutch 20 is engaged, the power output from the engine 12 is transmitted from the engine connecting shaft 34 to the driving wheels 14 via the K0 clutch 20, the electric motor connecting shaft 36, the torque converter 22, the automatic transmission 24, the propeller shaft 28, the differential gear 30, the drive shaft 32, etc. in this order. The power output from the electric motor MG is transmitted from the electric motor connecting shaft 36 to the driving wheels 14 via the torque converter 22, the automatic transmission 24, the propeller shaft 28, the differential gear 30, the drive shaft 32, etc. in this order, regardless of whether the K0 clutch 20 is engaged or disengaged.

[0029] The vehicle 10 includes an electronic control device 90. The electronic control device 90 includes a so-called microcomputer equipped with, for example, a CPU, RAM, ROM, an input / output interface, and the like, and the CPU executes various controls of the vehicle 10 by performing signal processing according to a program previously stored in the ROM while utilizing the temporary storage function of the RAM. The electronic control device 90 includes computers for engine control, electric motor control, hydraulic control, and the like as necessary. The electronic control device 90 corresponds to the "control device" in the present invention.

[0030] The electronic control device 90 receives various signals based on detection values ​​from various sensors provided in the vehicle 10 (e.g., engine rotation speed sensor 70, turbine rotation speed sensor 72, output rotation speed sensor 74, electric motor rotation speed sensor 76, accelerator opening sensor 78, throttle valve opening sensor 80, battery sensor 84, etc.) (e.g., engine rotation speed Ne [rpm] which is the rotation speed of the engine 12, turbine rotation speed Nt which is the same value as the AT input rotation speed Ni, AT output rotation speed No corresponding to the vehicle speed V, electric motor rotation speed Nmg [rpm] which is the rotation speed of the electric motor MG, accelerator opening θacc [%] which is the driver's accelerator operation amount which indicates the magnitude of the driver's acceleration operation, throttle valve opening θth [%] which is the opening of the electronic throttle valve, battery temperature THbat [°C] of the battery 54, battery charge / discharge current Ibat [A], battery voltage Vbat [V], etc.).

[0031] The electronic control device 90 outputs various command signals (e.g., an engine control signal Se for controlling the engine 12, an electric motor control signal Smg for controlling the electric motor MG, a CB hydraulic control signal Sbc for controlling the gear shift engagement device CB, a K0 hydraulic control signal Sk0 for controlling the K0 clutch 20, an LU hydraulic control signal Slu for controlling the lock-up clutch 40, an EOP control signal Seop for controlling the EOP 60, etc.) to each device (e.g., an engine control device 50, an inverter 52, a hydraulic control circuit 56, a pump motor 62, etc.) provided in the vehicle 10.

[0032] The electronic control unit 90 functionally comprises a hybrid control unit 92 , a clutch control unit 94 , a gear shift control unit 96 , and an inertia detection unit 98 .

[0033] The hybrid control unit 92 functionally comprises an engine control unit 92a that controls the operation of the engine 12, and an electric motor control unit 92b that controls the operation of the electric motor MG via the inverter 52, and performs hybrid drive control using the engine 12 and the electric motor MG, etc., using these control functions.

[0034] The hybrid control unit 92 calculates the amount of drive required by the driver for the vehicle 10, for example, by applying the actual accelerator opening θacc and vehicle speed V to a drive demand map. The drive demand map is a map in which the relationship between the accelerator opening θacc, the vehicle speed V, and the drive demand is determined in advance experimentally or by design and stored. The drive demand is, for example, the required drive torque Trdem [Nm] at the drive wheels 14. In other words, the required drive torque Trdem is the required drive power Prdem [W] at the vehicle speed V at that time. The drive demand can also be the required drive force Frdem [N] at the drive wheels 14, the required output torque at the transmission output shaft 26, or the like. In calculating the drive demand, the AT output rotation speed No, or the like, can be used instead of the vehicle speed V.

[0035] The hybrid control unit 92 outputs an engine control signal Se for controlling the engine 12 and an electric motor control signal Smg for controlling the electric motor MG so as to realize the required driving power Prdem, taking into consideration the transmission loss, the auxiliary load, the gear ratio γat of the automatic transmission 24, the chargeable electric power Win [W] and the dischargeable electric power Wout [W] of the battery 54, etc. The engine control signal Se is, for example, a command value for the engine power Pe [W], which is the power of the engine 12 that outputs the engine torque Te at the engine rotation speed Ne at that time. The electric motor control signal Smg is, for example, a command value for the power consumption Wm [W] of the electric motor MG that outputs the electric motor torque Tmg at the electric motor rotation speed Nmg at that time.

[0036] The chargeable power Win of the battery 54 is the maximum power that can be input, which specifies the limit on the input power of the battery 54, and indicates the input limit of the battery 54. The dischargeable power Wout of the battery 54 is the maximum power that can be output, which specifies the limit on the output power of the battery 54, and indicates the output limit of the battery 54. The chargeable power Win and dischargeable power Wout of the battery 54 are calculated by the electronic control device 90 based on, for example, the battery temperature THbat and the state of charge value SOC [%] of the battery 54 (the ratio of the amount of charge actually stored to a predetermined full charge capacity).

[0037] When the required drive torque Trdem can be satisfied only by the output of the electric motor MG, the hybrid control unit 92 sets the drive mode to the motor drive (=BEV drive) mode. In the BEV drive mode, the hybrid control unit 92 performs BEV (Battery Electric Vehicle) drive, which runs by outputting drive force for driving only from the electric motor MG among the drive force sources for driving (engine 12, electric motor MG) when the K0 clutch 20 is in the released state. On the other hand, when the required drive torque Trdem cannot be satisfied without using at least the output of the engine 12, the hybrid control unit 92 sets the drive mode to the engine drive mode, i.e., hybrid drive (=HEV drive) mode. In the HEV drive mode, the hybrid control unit 92 performs engine drive, i.e., HEV (Hybrid Electric Vehicle) drive, which runs by outputting drive force for driving only from the engine 12 among the drive force sources for driving (engine 12, electric motor MG) when the K0 clutch 20 is in the fully engaged state. On the other hand, even if the required drive torque Trdem can be satisfied only by the output of the electric motor MG, the hybrid control unit 92 establishes the HEV driving mode when the state of charge value SOC of the battery 54 is less than a predetermined engine start threshold value or when warming up of the engine 12 or the like is required. The engine start threshold value is a predetermined threshold value for determining that the state of charge value SOC is at a value at which the engine 12 needs to be forcibly started to charge the battery 54. In this way, the hybrid control unit 92 switches between the BEV driving mode and the HEV driving mode by automatically stopping the engine 12 during HEV driving and restarting the engine 12 after the engine has stopped, starting the engine 12 during BEV driving, automatically stopping the engine 12 while the vehicle is stopped and restarting the engine 12 after the engine has stopped, based on the required drive torque Trdem, etc.

[0038] The engine control unit 92a controls the engine torque Te so as to realize a drive demand amount for the vehicle 10. The electric motor control unit 92b controls the electric motor torque Tmg so as to realize a drive demand amount for the vehicle 10. Specifically, in the BEV driving mode, the electric motor control unit 92b controls the electric motor torque Tmg so as to realize the required drive torque Trdem. In the HEV driving mode, the engine control unit 92a controls the engine torque Te so as to realize all or a part of the required drive torque Trdem, and the electric motor control unit 92b controls the electric motor torque Tmg so as to compensate for the torque that is insufficient in the engine torque Te with respect to the required drive torque Trdem.

[0039] The hybrid control unit 92 further includes, functionally, a start determination unit 92c that determines whether or not the engine 12 should be started, and a start control unit 92d that executes start control of the engine 12 (hereinafter, referred to as "engine start control").

[0040] The start determination unit 92c determines whether or not a start of the engine 12 has been requested. That is, the start determination unit 92c determines whether or not there is a request to start the engine 12. For example, in the BEV driving mode, the start determination unit 92c determines that there is a request to start the engine 12 when (a) the required drive torque Trdem has increased beyond a range that can be covered only by the output of the electric motor MG, (b) warming up of the engine 12, etc. is required, or (c) the state of charge value SOC of the battery 54 is less than the engine start threshold.

[0041] When the start determination unit 92c determines that the start of the engine 12 is requested, the clutch control unit 94 controls the K0 clutch 20 to execute engine start control.

[0042] For example, when the engine start control is the early ignition start method, the clutch control unit 94 controls the K0 clutch command pressure Pk0 so as to obtain a K0 torque Tk0 for transmitting a cranking torque Tcr [Nm], which is a torque for increasing the engine rotation speed Ne, to the engine 12 side. The early ignition start method is a start method in which the K0 clutch 20 is engaged to crank the engine 12 by the electric motor MG, fuel is injected and ignited into the engine 12 before the synchronization of the K0 clutch 20 is completed, and when the combustion can be continued, the K0 clutch 20 is temporarily released, and then the K0 clutch 20 is re-engaged. "Completion of synchronization of the K0 clutch 20" means that the rotation speed of the engine 12 side of the K0 clutch 20 (= engine rotation speed Ne) and the rotation speed of the electric motor MG side of the K0 clutch 20 (= electric motor rotation speed Nmg) match. In the early ignition start method, fuel is injected and ignited near the compression TDC (Top Dead Center) when the engine speed Ne is low, and the engine 12 is started. The "start" of the engine 12 refers not only to the time when the engine 12 is completely exploded (starts operation) and can operate independently, but also to a series of control operations related to the start of the engine 12 until the K0 clutch 20 is fully engaged. The clutch control unit 94 transmits the cranking torque Tcr to the engine 12 side until the fuel is injected and ignited into the engine 12 before the synchronization of the K0 clutch 20 is completed and the combustion can be continued. When the combustion of the engine 12 can be continued, the clutch control unit 94 ends the cranking, temporarily releases the K0 clutch 20, and then re-engages the K0 clutch 20. The clutch control unit 94 determines whether or not the cranking has not yet ended.

[0043] When the start determination unit 92c determines that the start of the engine 12 is requested, the start control unit 92d controls the engine 12 and the electric motor MG to execute engine start control. For example, the start control unit 92d outputs to the inverter 52 an electric motor control signal Smg for causing the electric motor MG to output the cranking torque Tcr until cranking ends, in accordance with the switching of the K0 clutch 20 from the released state to the fully engaged state by the clutch control unit 94. That is, the start control unit 92d outputs to the inverter 52 an electric motor control signal Smg for controlling the electric motor MG to output the cranking torque Tcr until cranking ends in the engine start control.

[0044] When the start determination unit 92c determines that the start of the engine 12 has been requested, the start control unit 92d outputs an engine control signal Se to the engine control device 50 for starting fuel supply, ignition, and the like, in conjunction with cranking of the engine 12 by the K0 clutch 20 and the electric motor MG. That is, the start control unit 92d outputs an engine control signal Se to the engine control device 50 for controlling the engine 12 so that the engine 12 starts operating in the engine start control. In this way, when the start determination unit 92c determines that the start of the engine 12 has been requested, the start control unit 92d executes the engine start control. Note that the start control unit 92d determines whether or not the engine start control has already been started.

[0045] In engine start control during BEV driving, the start control unit 92d causes the electric motor MG to output an electric motor torque Tmg that is the electric motor torque Tmg for BEV driving, that is, the electric motor torque Tmg that generates the drive torque Tr [Nm], plus the cranking torque Tcr.

[0046] The shift control unit 96 judges whether or not to shift the automatic transmission 24 by using, for example, a shift map, and outputs a CB hydraulic control signal Sbc for executing shift control as necessary to the hydraulic control circuit 56. The shift map is a predetermined relationship having a shift line for judging whether or not to shift the automatic transmission 24 on a two-dimensional coordinate system having, for example, vehicle speed V and required driving torque Trdem as variables. In the shift map, the AT output rotation speed No may be used instead of the vehicle speed V, and the required driving force Frdem, accelerator opening θacc, throttle valve opening θth, etc. may be used instead of the required driving torque Trdem.

[0047] The shift phase (shift stage) of the automatic transmission 24 includes a torque phase and an inertia phase. The torque phase is a phase during the shift period (the period from the start of shift control to the completion of shift control) of the automatic transmission 24 during which the output torque of the automatic transmission 24 changes. The inertia phase is a phase during the shift period of the automatic transmission 24 during which the turbine rotation speed Nt, which is the same value as the AT input rotation speed Ni in the automatic transmission 24, changes from a theoretical pre-shift turbine rotation speed Nt_pre (theoretical turbine rotation speed Nt calculated from the gear ratio γat in the gear stage before shifting and the vehicle speed V) to a theoretical post-shift turbine rotation speed Nt_post (theoretical turbine rotation speed Nt calculated from the gear ratio γat in the gear stage after shifting and the vehicle speed V). The torque phase is also a period during which the CB torque Tcb, which is the transmission torque capacity of the engagement side engagement device CBcon and the release side engagement device CBdis, changes.

[0048] When a request to start the engine 12 occurs during a period when the gear shift control is not being executed during BEV driving, the engine start control is executed by the start control unit 92d as described above. Also, when the gear shift control is executed during a period when the engine start control is not being executed by the start control unit 92d during BEV driving, the gear shift control is executed by the gear shift control unit 96 as described above.

[0049] There are cases where engine start control and gear shift control are executed simultaneously while the BEV is running. In such a case, the start control unit 92d executes the engine start control, and the gear shift control unit 96 advances the torque phase of the gear shift control but delays the start of the inertia phase until synchronization of the K0 clutch 20 is completed. Completion of synchronization of the K0 clutch 20 completes the engine start control. Therefore, after completion of the engine start control, the gear shift control unit 96 cancels the delay in the start of the inertia phase and starts the inertia phase.

[0050] However, as described above, when engine start control and gear shift control are executed simultaneously during BEV running, the inertia phase of the gear shift control may be started unintentionally before the completion of the engine start control. The inertia phase in the gear shift control cannot be advanced in reverse, i.e., in the reverse direction. Therefore, if the inertia phase is advanced when the gear shift control is a downshift control, the motor rotation speed Nmg, which is the rotation speed of the automatic transmission 24 side (= the motor MG side) of the K0 clutch 20, increases. As the motor rotation speed Nmg increases, the required amount of increase in the engine rotation speed Ne, which is the rotation speed of the engine 12 side of the K0 clutch 20, increases, so that the completion of synchronization of the K0 clutch 20 may be delayed, i.e., the completion of the engine start control may be delayed. Furthermore, when the shift control is an upshift control, if the inertia phase is advanced, the motor rotation speed Nmg, which is the rotation speed on the automatic transmission 24 side (= motor MG side) of the K0 clutch 20, decreases, so there is no risk of delaying the completion of synchronization of the K0 clutch 20.

[0051] When engine start control is executed by the start control unit 92d and the clutch control unit 94 and gear shift control is executed by the gear shift control unit 96, the inertia detection unit 98 detects whether the inertia phase in the downshift control has started before synchronization of the K0 clutch 20 is completed.

[0052] For example, whether or not the synchronization of the K0 clutch 20 has not yet been completed can be detected by whether or not a state in which the differential rotation speed ΔNk0 [rpm] (=|Nmg-Ne|) between the engine rotation speed Ne and the electric motor rotation speed Nmg is within a range equal to or less than a predetermined judgement differential rotation speed ΔNk0_jdg [rpm] (>0) continues for a predetermined period TM_jdg [ms]. Specifically, if the differential rotation speed ΔNk0 is within the range of the predetermined judgement differential rotation speed ΔNk0_jdg continues for the predetermined period TM_jdg, it is detected that the synchronization of the K0 clutch 20 has been completed, and if not, it is detected that the synchronization of the K0 clutch 20 has not yet been completed. The predetermined judgement differential rotation speed ΔNk0_jdg and the predetermined period TM_jdg are judgement values ​​that are experimentally or design-based in advance for detecting the completion of the synchronization of the K0 clutch 20.

[0053] For example, whether or not the inertia phase in downshift control has started can be detected based on whether or not the turbine rotation speed Nt has changed from the theoretical pre-shift turbine rotation speed Nt_pre to the theoretical post-shift turbine rotation speed Nt_post. In downshift control, the post-shift turbine rotation speed Nt_post becomes higher than the pre-shift turbine rotation speed Nt_pre. Specifically, when the turbine rotation speed Nt becomes higher by a predetermined judgment rotation speed ΔNt_jdg [rpm] from the pre-shift turbine rotation speed Nt_pre to the post-shift turbine rotation speed Nt_post, the start of the inertia phase is detected. The predetermined judgment rotation speed ΔNt_jdg is a value near zero (>0) that is experimentally or design-wise determined in advance in order to detect the start of the inertia phase. In upshift control, the post-shift turbine rotation speed Nt_post becomes lower than the pre-shift turbine rotation speed Nt_pre.

[0054] The inertia detection unit 98 detects that synchronization of the K0 clutch 20 has not yet been completed and detects that the inertia phase in the downshift control has started, thereby detecting that the inertia phase in the downshift control has started before synchronization of the K0 clutch 20 is completed.

[0055] When the inertia detection unit 98 detects that the inertia phase in the downshift control has started before the synchronization of the K0 clutch 20 is completed, the shift control unit 96 advances the inertia phase in the downshift control, and the start control unit 92d and the clutch control unit 94 execute control to synchronize the K0 clutch 20. Specifically, the shift control unit 96 controls the release side command pressure Pdis and the engagement side command pressure Pcon according to an inertia phase advancement time chart that is determined in advance experimentally or by design, for example, so that the inertia phase advancement speed and the engagement shock are within an allowable range. In addition, the start control unit 92d controls the engine 12 and the electric motor MG, and the clutch control unit 94 controls the K0 clutch command pressure Pk0 so that the differential rotation ΔNk0 gradually decreases. The K0 torque Tk0 when the control to synchronize the K0 clutch 20 is executed is referred to as the synchronization torque Tsyn [Nm]. When it is detected that the inertia phase has started before the synchronization of the K0 clutch 20 is completed, the clutch control unit 94 changes the synchronization torque Tsyn to an increased (raised) value compared to when the inertia phase has not been detected. Preferably, the clutch control unit 94 performs a lower limit guard process on the synchronization torque Tsyn. The lower limit guard process is a process for setting the synchronization torque Tsyn to a predetermined lower limit value or higher so that the rate of increase of the engine rotation speed Ne is equal to or higher than a predetermined rate. The predetermined rate and the predetermined lower limit value are values ​​that are experimentally or design-wise determined in advance so that the period until the synchronization of the K0 clutch 20 is completed falls within an allowable range. When the increased (raised) synchronization torque Tsyn is less than the predetermined lower limit value, the synchronization torque Tsyn is increased to the predetermined lower limit value.

[0056] If the inertia detection unit 98 does not detect that the inertia phase in the downshift control has started before synchronization of the K0 clutch 20 is completed, the start control unit 92d and the clutch control unit 94 execute control to synchronize the K0 clutch 20, and the gear shift control unit 96 delays the start of the inertia phase in the downshift control until synchronization of the K0 clutch 20 is completed. In this case, the clutch control unit 94 does not increase (raise) the synchronization torque Tsyn as described above.

[0057] Regardless of whether or not the start of the inertia phase in the downshift control is detected before the synchronization of the K0 clutch 20 is completed, after the synchronization of the K0 clutch 20 is completed, the clutch control unit 94 controls the K0 clutch command pressure Pk0 so that the K0 clutch 20 is in a fully engaged state. The K0 torque Tk0 when the control for bringing the K0 clutch 20 into the fully engaged state is being executed is referred to as the engagement torque Tcon [Nm].

[0058] In the case where the start of the inertia phase in the downshift control is not detected before the completion of synchronization of the K0 clutch 20, the gear shift control unit 96 cancels the delay in the start of the inertia phase in the downshift control and starts the inertia phase after the completion of synchronization of the K0 clutch 20. Specifically, the gear shift control unit 96 controls the release side command pressure Pdis and the engagement side command pressure Pcon in accordance with, for example, the inertia phase progression time chart described above.

[0059] Fig. 2 is an example of a flowchart explaining the control operation of the electronic control device 90 shown in Fig. 1. The flowchart in Fig. 2 is repeatedly executed when engine start control and gear shift control are executed simultaneously while the BEV is running. Fig. 2 shows an example in which engine start control is executed by the early ignition start method.

[0060] First, in step S10 (hereinafter, step will be omitted) corresponding to the function of the start control unit 92d, it is determined whether or not the engine start control has been started. If the determination in S10 is positive, it is determined in S20 corresponding to the function of the clutch control unit 94 whether or not the cranking has not been completed. If the determination in S10 is negative, the process returns.

[0061] If the judgment in S20 is positive, in S30, which corresponds to the functions of the start control unit 92d and the clutch control unit 94, the cranking torque Tcr is calculated, and the K0 torque Tk0 is controlled to the cranking torque Tcr to perform cranking, and then the process returns.

[0062] If the determination in S20 is negative, in S40, which corresponds to the function of the inertia detection unit 98, it is detected whether or not synchronization of the K0 clutch 20 has not yet been completed.

[0063] If the detection in S40 is positive, the synchronizing torque Tsyn of the K0 clutch 20 is calculated in S50, which corresponds to the function of the clutch control unit 94, and it is detected whether the inertia phase in the downshift control has started in S60, which corresponds to the function of the inertia detection unit 98. If the detection in S40 is negative, the engaging torque Tcon of the K0 clutch 20 is calculated in S90, which corresponds to the function of the clutch control unit 94, and the K0 torque Tk0 is controlled to the engaging torque Tcon, and then the process returns.

[0064] If the detection in S60 is positive, in S70 corresponding to the function of the clutch control unit 94, the synchronizing torque Tsyn calculated in S50 is increased and a lower limit guard process is performed, and the K0 torque Tk0 is controlled to the synchronizing torque Tsyn after the lower limit guard process, and then the process returns. If the detection in S60 is negative, in S80 corresponding to the function of the clutch control unit 94, the K0 torque Tk0 is controlled to the synchronizing torque Tsyn calculated in S50, and then the process returns.

[0065] Fig. 3 is a time chart in which the flowchart of Fig. 2 is executed, and is an example of a case where the start of the inertia phase in the downshift control is not detected before synchronization of the K0 clutch 20 is completed. This time chart is an example of a case where the detection in S60 in the flowchart of Fig. 2 is never affirmative. In this time chart, the lock-up clutch 40 is in a released state. The horizontal axis of Fig. 3 is time t [ms].

[0066] Before time t1, the vehicle is in a BEV running state, for example, a low vehicle speed V and a low load running state with a low required drive torque Trdem. In addition, the K0 clutch 20 is in a released state, and the K0 clutch command pressure Pk0 is set to the hydraulic pressure value Pk0a.

[0067] At time t1, the accelerator opening θacc starts to increase due to an accelerator operation by the driver (for example, further depression of an accelerator pedal (not shown)).

[0068] As the accelerator opening θacc increases, the required drive torque Trdem increases, and it is determined that the required drive torque Trdem cannot be satisfied by the electric motor MG alone among the driving force sources (engine 12, electric motor MG), and engine start control is started at time t2 (>t1). At time t2, in order to pack the K0 clutch 20 quickly, the K0 clutch command pressure Pk0 is set to a hydraulic pressure value Pk0f for rapid filling. The hydraulic pressure value Pk0f is, for example, the line pressure PL. During the period from time t2 to time t3 (>t2) (rapid filling period), the K0 clutch command pressure Pk0 is set to the hydraulic pressure value Pk0f, so that the K0 clutch 20 is quickly packed. At time t3 (>t2), the K0 clutch command pressure Pk0 is reduced from the hydraulic pressure value Pk0f to the hydraulic pressure value Pk0e. This hydraulic pressure value Pk0e is the K0 clutch command pressure Pk0 at which the K0 torque Tk0 becomes the cranking torque Tcr.

[0069] At time t4 (>t2), power-on downshift control is started. Power-on downshift control is a downshift control that is executed by increasing the accelerator opening θacc by the accelerator operation by the driver. At time t4, re-engagement of the gear shift engagement device CB is started. Before time t4, the release side command pressure Pdis is set to a hydraulic pressure value Patb [Pa] that brings the release side engagement device CBdis into a fully engaged state, and the engagement side command pressure Pcon is set to a hydraulic pressure value Pata [Pa] that brings the engagement side engagement device CBcon into a released state. The engagement side command pressure Pcon and the release side command pressure Pdis during the period after time t4 (from time t4 to time t9 described later) are set to hydraulic pressure values ​​that are experimentally or design-predetermined so as to advance the torque phase in the downshift control but not to start the inertia phase. For example, during most of the period from time t4 to time t9, the release side command pressure Pdis is set to be higher than the engagement side command pressure Pcon.

[0070] At time t5 (>t4), the engine speed Ne starts to increase due to cranking.

[0071] At time t6 (>t5), fuel is injected into the engine 12, and the fuel is ignited, so that the combustion can continue. In other words, the engine 12 is in a state where it can operate independently after a complete explosion. Therefore, at time t6, the K0 clutch command pressure Pk0 is reduced from the hydraulic pressure value Pk0e to the hydraulic pressure value Pk0b, and the K0 clutch 20 is temporarily released. During the period from time t6 to time t7 (>t6), the K0 clutch command pressure Pk0 is set to the hydraulic pressure value Pk0b. The hydraulic pressure value Pk0b is a hydraulic pressure value that is experimentally or design-wise determined in advance in order to quickly release the K0 clutch 20.

[0072] At time t7 (>t6), the K0 clutch command pressure Pk0 is increased from the hydraulic pressure value Pk0b to the hydraulic pressure value Pk0c to start re-engagement of the K0 clutch 20. The hydraulic pressure value Pk0c is a hydraulic pressure value at which the K0 torque Tk0 becomes the synchronizing torque Tsyn.

[0073] During the period from time t8 (>t7) to time t9 (>t8), the K0 clutch command pressure Pk0 is gradually increased from the hydraulic pressure value Pk0c at a constant rate of increase, and at time t9, it is increased to the hydraulic pressure value Pk0f. Due to this increase in the K0 clutch command pressure Pk0, before time t9, the state in which the differential rotation ΔNk0 of the K0 clutch 20 is within a range equal to or less than a predetermined judged differential rotation ΔNk0_jdg continues for a predetermined period TM_jdg. As described above, the hydraulic pressure value Pk0f is, for example, the line pressure PL. By making the K0 clutch command pressure Pk0 the hydraulic pressure value Pk0f at time t9, the K0 torque Tk0 is set to a value capable of transmitting the engine torque Te. This completes the synchronization of the K0 clutch 20, and the engine start control is completed.

[0074] At time t9 when synchronization of the K0 clutch 20 is completed, control of the engagement command pressure Pcon and the release command pressure Pdis is started so that the inertia phase in the downshift control is started. Specifically, from time t9 onwards (the period from time t9 to time t12 described later), the release command pressure Pdis and the engagement command pressure Pcon are controlled according to the inertia phase progression time chart described above. At time t9, the release command pressure Pdis starts to decrease, and at time t10 (>t9), the release command pressure Pdis is made lower than the engagement command pressure Pcon.

[0075] At time t10, the turbine rotation speed Nt starts to change from the pre-shift turbine rotation speed Nt_pre to the post-shift turbine rotation speed Nt_post, that is, the inertia phase of the downshift control begins. Since the lock-up clutch 40 of the torque converter 22 is in a disengaged state and the turbine wheel 22b and the pump wheel 22a are fluidly connected to each other, the engine rotation speed Ne and the electric motor rotation speed Nmg also increase with the increase in the turbine rotation speed Nt.

[0076] At time t11 (>t10), the turbine rotation speed Nt becomes the post-shift turbine rotation speed Nt_post, and the inertia phase ends.

[0077] During the period from time t11 when the inertia phase ends to time t12, the disengagement command pressure Pdis is lowered to a hydraulic pressure value Pata that brings the disengagement engagement device CBdis into a disengaged state, and the engagement command pressure Pcon is raised to a hydraulic pressure value Patb that brings the engagement engagement device CBcon into a fully engaged state. The hydraulic pressure value Patb is, for example, the line pressure PL. This completes the downshift control.

[0078] FIG. 4 is a time chart in which the flowchart of FIG. 2 is executed, and is an example of a case where it is detected that the inertia phase in the downshift control has started before the synchronization of the K0 clutch 20 is completed. This time chart is an example of a case where the detection of S60 in the flowchart of FIG. 2 is affirmative. The horizontal axis of FIG. 4 is time t [ms]. The period before time t7 in this time chart is the same as the period before time t7 in the time chart of FIG. 3 described above. Therefore, the following description will focus on the parts that are different from FIG. 3, and the parts that are common to FIG. 3 will be given the same reference numerals and their description will be omitted as appropriate.

[0079] At time t20 (>t7), the turbine rotation speed Nt begins to rise from the pre-shift turbine rotation speed Nt_pre; in other words, the inertia phase of the downshift control is unintentionally started before synchronization of the K0 clutch 20 is completed.

[0080] At time t21 (>t20), it is detected that the turbine rotation speed Nt is higher than the pre-shift turbine rotation speed Nt_pre by a predetermined judgment rotation speed ΔNt_jdg, and thus it is detected that the inertia phase has started before the synchronization of the K0 clutch 20 is completed. In response to the detection of the start of the inertia phase, at time t21, the K0 clutch command pressure Pk0 is increased from the hydraulic pressure value Pk0c to the hydraulic pressure value Pk0d. This increase in the K0 clutch command pressure Pk0 increases the synchronization torque Tsyn, and the engine rotation speed Ne is easily raised toward the electric motor rotation speed Nmg, thereby increasing the rate of increase of the engine rotation speed Ne. In addition, after time t21 (the period from time t21 to time t26 described later), the release side command pressure Pdis and the engagement side command pressure Pcon are controlled according to the inertia phase progression time chart described above. At time t21, the release side command pressure Pdis starts to decrease, and at time t22 (>t21), the release side command pressure Pdis is made lower than the engagement side command pressure Pcon.

[0081] During the period from time t23 (>t22) to time t25 (>t23), the K0 clutch command pressure Pk0 is gradually increased from the hydraulic pressure value Pk0d at a constant rate of increase, and at time t25, it is increased to the hydraulic pressure value Pk0f. Due to this increase in the K0 clutch command pressure Pk0, before time t25, the state in which the differential rotation speed ΔNk0 of the K0 clutch 20 is within a range equal to or smaller than a predetermined judgment differential rotation speed ΔNk0_jdg continues for a predetermined period TM_jdg. This completes the synchronization of the K0 clutch 20, and the engine start control is completed.

[0082] At time t24 (t25>t24>t23), the turbine rotation speed Nt becomes the post-shift turbine rotation speed Nt_post, and the inertia phase ends.

[0083] In this time chart, in the period from time t24 when the inertia phase ends to time t26 (>t24), the disengagement command pressure Pdis is lowered to the hydraulic pressure value Pata that puts the disengagement engagement device CBdis in the disengaged state, and the engagement command pressure Pcon is raised to the hydraulic pressure value Patb that puts the engagement engagement device CBcon in the fully engaged state, thereby completing the downshift control.

[0084] According to this embodiment, (A) in the case where the engine start control and the downshift control of the automatic transmission 24 are executed at the same time, (a-1) if the start of the inertia phase in the downshift control is not detected before the synchronization of the K0 clutch 20 is completed, the start of the inertia phase in the engine start control is delayed until the synchronization of the K0 clutch 20 is completed, and (a-2) if the start of the inertia phase is detected before the synchronization of the K0 clutch 20 is completed, the inertia phase is advanced, and the K0 clutch command pressure Pk0 for engaging the K0 clutch 20 in the engine start control is increased compared to the case where the start of the inertia phase is not detected. In this way, if the start of the inertia phase in the downshift control of the automatic transmission 24 is detected before the synchronization of the K0 clutch 20 is completed, the engine start control is advanced and the inertia phase is advanced. Furthermore, the K0 clutch command pressure Pk0 for engaging the K0 clutch 20 in the engine start control is increased compared to when the start of the inertia phase is not detected. By advancing the inertia phase in the downshift control, delays in the completion of the downshift control are suppressed, and by increasing the K0 clutch command pressure Pk0 for engaging the K0 clutch 20 in the engine start control, delays in the completion of synchronization of the K0 clutch 20 (i.e., delays in the completion of the engine start control) are suppressed. This makes it easier to achieve drivability that meets the driver's needs.

[0085] Although the embodiment of the present invention has been described in detail above with reference to the drawings, the present invention can be applied to other embodiments.

[0086] In the above embodiment, the automatic transmission 24 is of the planetary gear type, but the automatic transmission in the present invention may be a stepped transmission of other configurations, such as a constant meshing parallel shaft type.

[0087] 3 and 4 show an embodiment in which engine start control is started and power-on downshift control of the automatic transmission 24 is started in response to an accelerator operation that increases the accelerator opening θacc, but the present invention is not limited to this embodiment. For example, the embodiment may be such that engine start control is started when the state of charge value SOC of the battery 54 falls below the engine start threshold and downshift control is started when the vehicle speed V decreases.

[0088] In the above embodiment, the torque converter 22 is used as the fluid transmission device, but the present invention is not limited to this embodiment. For example, other fluid transmission devices, such as a fluid coupling that does not amplify torque, may be used as the fluid transmission device instead of the torque converter 22. Also, the fluid transmission device does not necessarily have to be provided, and may be replaced with, for example, a starting clutch.

[0089] In the above embodiment, the engine start control is the early ignition start method, but the present invention is not limited to this. For example, the engine start control may be a push start method. The push start method is a start method in which the K0 clutch 20 is engaged to increase the engine rotation speed Ne by the electric motor MG, and after the synchronization of the K0 clutch 20 is completed, fuel is injected into the engine 12, ignited, and started.

[0090] It should be noted that the above is merely an embodiment of the present invention, and the present invention can be embodied in various forms with various modifications and improvements based on the knowledge of those skilled in the art without departing from the spirit of the present invention. [Explanation of symbols]

[0091] 10: Hybrid vehicles 12: Engine (internal combustion engine) 20: K0 clutch (friction engagement device) 24: Automatic transmission 90: Electronic control device (control device) MG: Electric motor Pk0: K0 clutch command pressure (control pressure)

Claims

[Claim 1] A control device for a hybrid vehicle including an internal combustion engine and an electric motor as a driving force source for driving the vehicle, a hydraulic friction engagement device that connects and disconnects power transmission between the internal combustion engine and the electric motor, and an automatic transmission that changes the speed of a driving force output from the driving force source for driving the vehicle, When the start control of the internal combustion engine and the downshift control of the automatic transmission are executed simultaneously, if it is not detected that an inertia phase in the downshift control has started before synchronization of the friction engagement devices is completed, delaying the start of the inertia phase until synchronization of the friction engagement devices in the start control is completed; When it is detected that the inertia phase has started before the synchronization of the friction engagement device is completed, the inertia phase is advanced, and the control pressure for engaging the friction engagement device in the start control is increased compared to when the inertia phase has not been detected. A control device for a hybrid vehicle.

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