WO2012101792A1

WO2012101792A1 - Hybrid vehicle control device

Info

Publication number: WO2012101792A1
Application number: PCT/JP2011/051528
Authority: WO
Inventors: 寛英小林; 大坪　秀顕
Original assignee: トヨタ自動車株式会社
Priority date: 2011-01-26
Filing date: 2011-01-26
Publication date: 2012-08-02

Abstract

A hybrid vehicle (10) comprises: an engine (12); an electric motor (MG) functioning as a driving source; and a multistage automatic transmission (18) for selectively establishing a plurality of gear stages from predetermined speed change lines on the basis of vehicle traveling states. In a control device for the hybrid vehicle (10), at least part of a switching line and at least part of the speed change lines are shared with each other, the switching line being used for determining the switching between an EHV travel mode in which both the engine (12) and the electric motor (MG) are used as driving sources and an EV travel mode in which the electric motor (MG) is exclusively used as a driving source. The stop control and speed change control of the engine (12) are thereby synchronously executed, so that the occurrence of shock can be suppressed and the controls can be preferably prevented from becoming complicated.

Description

Control device for hybrid vehicle

The present invention relates to a control apparatus for a hybrid vehicle including a stepped automatic transmission, and more particularly to an improvement for reducing a shock when switching a traveling mode.

Hybrid vehicles that use an engine and an electric motor selectively as driving sources for traveling are known. In addition, as one aspect of such a hybrid vehicle, a plurality of shift speeds may be selectively established in a power transmission path between the engine and the drive wheels based on a traveling state of the vehicle from a predetermined shift line. One having a staged automatic transmission is known. In such a hybrid vehicle, an EHV traveling mode using the engine and the electric motor as a driving source and an EV traveling mode exclusively using the electric motor as a driving source are selectively established. The occurrence of a shock due to the engine stop at is a problem. Therefore, a technique for suppressing the occurrence of a shock at the time of switching from the EHV traveling mode to the EV traveling mode has been proposed. For example, the hybrid vehicle mode switching control device described in Patent Document 1 is the same. According to this technique, when releasing the first clutch when the engine is stopped when switching from the EHV travel mode to the EV travel mode, the engagement torque capacity of the second clutch provided on the automatic transmission side is reduced, It is said that the engine stop shock can be reduced.

JP 2007-253780 A

However, in the conventional technique, when the engine is stopped regardless of whether or not the automatic transmission is shifted, the engagement torque capacity of the second clutch is uniformly reduced. Along with the control of the second clutch, it is necessary to determine a control pattern according to whether or not the shift of the automatic transmission is performed, and there is an adverse effect that the control becomes complicated. Further, by reducing the engagement torque capacity of the second clutch that functions as an input clutch of the automatic transmission, the control for judging a new shift while the engine is stopped is complicated, or the shift control is delayed. It was a new problem. For this reason, in a hybrid vehicle equipped with a stepped automatic transmission, there has been a demand for development of a control device for the hybrid vehicle that reduces shocks when the travel mode is switched.

The present invention has been made in the background of the above circumstances, and an object of the present invention is to reduce the shock at the time of switching the driving mode in a hybrid vehicle including a stepped automatic transmission. It is to provide a control device.

In order to achieve such an object, the gist of the invention according to claim 1 is that an engine, an electric motor functioning as a drive source, and a plurality of shifts based on a running state of the vehicle from a predetermined shift line. A control device for a hybrid vehicle including a stepped automatic transmission that selectively establishes a stage, and an EV mode that uses the engine and an electric motor as driving sources and an EV that exclusively uses the electric motor as a driving source At least a part of the switching line for determining switching to the traveling mode and at least a part of the shift line are shared.

In this case, the engine, the electric motor functioning as a drive source, and the stepped automatic transmission that selectively establishes a plurality of shift stages based on the traveling state of the vehicle from a predetermined shift line. In the hybrid vehicle control apparatus, at least a part of a switching line for determining switching between an EHV traveling mode using the engine and the electric motor as a driving source and an EV traveling mode exclusively using the electric motor as a driving source; Since at least a part of the shift line is shared, it is preferable that the engine stop control and the shift control are executed synchronously to suppress the occurrence of shock and make the control complicated. Can be prevented. That is, it is possible to provide a control device for a hybrid vehicle that reduces a shock when the travel mode is switched in a hybrid vehicle including a stepped automatic transmission.

In the invention according to claim 1, preferably, at least a part of a switching line for determining switching from the EHV traveling mode to the EV traveling mode, and at least one of upshift lines among the shift lines. The part is shared. By so doing, the engine stop control and the upshift control are executed synchronously, so that the occurrence of a shock can be more suitably suppressed.

In the invention according to

claim

1 or 2, preferably, the shift line is determined so as to determine the shift stage based on a vehicle speed and a required amount of driving force, and the automatic transmission The switching line for determining the switching from the EV traveling mode to the HEV traveling mode while the vehicle is maintained at the first speed is such that the automatic transmission is moved from the first speed while the vehicle is maintained in the EV traveling mode. Also, it is determined on the higher driving force request amount side than the shift line for determining the shift to the high speed stage. In this way, for example, when the vehicle is in the EV travel mode and the automatic transmission is at the first speed, the engine stop control and the shift control are synchronized when the vehicle speed increases and the accelerator is turned off. This is executed effectively to suppress the occurrence of shock.

In the invention according to

claim

1 or 2, the invention according to claim 3 dependent on claim 1, or the invention according to claim 3 dependent on claim 2, it is preferable that the shift line includes a vehicle speed and The shift speed is determined based on the required driving force, and the portion of the shift line that is shared with the switching line gradually decreases the corresponding required driving force as the vehicle speed increases. It is determined to be. In this way, the engine stop control and the shift control are executed synchronously based on a practical relationship shared by the shift line and the switching line.

It is a figure which shows notionally the structure of the drive system which concerns on the hybrid vehicle which is one Example of this invention. FIG. 2 is a cross-sectional view showing a part of the hybrid vehicle of FIG. It is a functional block diagram explaining the principal part of the control function with which the electronic control apparatus in the hybrid vehicle of FIG. 1 was equipped. FIG. 2 is a diagram illustrating a shift map used for shift determination by an electronic control unit in the hybrid vehicle of FIG. 1 and a switching map used for travel mode switching determination. FIG. 5 is a diagram illustrating specific shift control and travel mode switching control using the shift map and switching map shown in FIG. 4. 2 is a time chart illustrating an example of a change with time of a turbine rotation speed and an engagement pressure of each hydraulic friction engagement element at the time of shifting of an automatic transmission in the hybrid vehicle of FIG. 1. It is a figure which shows collectively the other shift map used for the shift determination by the electronic controller in the hybrid vehicle of FIG. 1, and the switch map used for driving mode switch determination. 2 is a flowchart for explaining a main part of synchronous execution control of shift control and travel mode switching control by an electronic control unit in the hybrid vehicle of FIG. 1. It is a figure which shows notionally the structure of the drive system which concerns on the other hybrid vehicle to which this invention is applied suitably. It is a figure which shows notionally the structure of the drive system which concerns on another hybrid vehicle to which this invention is applied suitably. It is a figure which shows notionally the structure of the drive system which concerns on another hybrid vehicle to which this invention is applied suitably.

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

FIG. 1 is a diagram conceptually showing the structure of a drive system related to a hybrid vehicle 10 according to an embodiment of the present invention. The hybrid vehicle 10 shown in FIG. 1 includes an engine 12 and an electric motor MG that function as a driving source, and the driving force generated by the engine 12 and the electric motor MG includes a torque converter 16, an automatic transmission 18, and a difference. It is configured to be transmitted to a pair of left and right drive wheels 24 via a moving gear device 20 and a pair of left and right axles 22, respectively. With this configuration, the hybrid vehicle 10 is driven using at least one of the engine 12 and the electric motor MG as a driving source for traveling. That is, in the hybrid vehicle 10, the engine traveling exclusively using the engine 12 as a driving source for traveling, the EV traveling (motor traveling) exclusively using the electric motor MG as a driving source for traveling, and the engine 12 and the electric motor MG. Any one of EHV traveling (hybrid traveling) using as a driving source for traveling is selectively established.

The engine 12 is, for example, an internal combustion engine such as a direct injection gasoline engine or a diesel engine in which fuel is directly injected into a combustion chamber. Further, in order to control the drive (output torque) of the engine 12, output control including a throttle actuator that controls opening and closing of an electronic throttle valve, a fuel injection device that performs fuel injection control, an ignition device that performs ignition timing control, and the like. A device 14 is provided. The output control device 14 controls the opening and closing of the electronic throttle valve by the throttle actuator for throttle control in accordance with a command supplied from an electronic control device 58 to be described later, as well as the fuel from the fuel injection device for fuel injection control. The engine 12 is controlled for output by controlling injection and controlling the ignition timing by the ignition device for ignition timing control.

The electric motor MG is, for example, a motor generator having a function as a motor (motor) that generates driving force and a generator (generator) that generates reaction force, and has at least a function as a motor that generates driving force. is doing. The power transmission path between the engine 12 and the electric motor MG is provided with a clutch K0 that controls power transmission in the power transmission path according to the engaged state. That is, the crankshaft 26 that is an output member of the engine 12 is selectively connected to the rotor 30 of the electric motor MG through the clutch K0. The rotor 30 of the electric motor MG is connected to a front cover 32 that is an input member of the torque converter 16.

The clutch K0 is, for example, a multi-plate hydraulic friction engagement device whose engagement is controlled by a hydraulic actuator, and its engagement state is engaged (completely engaged) according to the hydraulic pressure supplied from the hydraulic control circuit 34. ), Slip engagement, or release (fully open). When the clutch K0 is engaged, power transmission in the power transmission path between the crankshaft 26 and the front cover 32 is performed (connected), while the clutch K0 is released, thereby The power transmission in the power transmission path between the crankshaft 26 and the front cover 32 is interrupted. Further, when the clutch K0 is slip-engaged, power transmission according to the transmission torque of the clutch K0 is performed in the power transmission path between the crankshaft 26 and the front cover 32.

The automatic transmission 18 is a stepped automatic transmission mechanism in which any one of a plurality of predetermined shift speeds (speed ratios) is selectively established, and a plurality of engagements are performed to perform such a shift. Constructed with elements. For example, a plurality of hydraulic friction engagement devices that are engaged and controlled by hydraulic actuators such as a multi-plate clutch and a brake are provided, and the plurality of hydraulic friction engagement devices according to the hydraulic pressure supplied from the hydraulic control circuit 34 are provided. By selectively engaging or disengaging the engagement device, a plurality of (for example, first to fourth speed) forward shift stages (forward gears) according to the combination state of the hydraulic friction engagement devices. Stage, forward travel gear stage) or reverse shift stage (reverse gear stage, reverse travel gear stage) is selectively established.

FIG. 2 is a cross-sectional view showing a part of the hybrid vehicle 10 of FIG. 1 with a part thereof cut away in order to explain the configuration in the vicinity of the electric motor MG and the torque converter 16. The electric motor MG, the torque converter 16, the automatic transmission 18, and the crankshaft 26 are configured substantially symmetrically with respect to the common shaft center C. In FIG. It is omitted. As shown in FIG. 2, the electric motor MG, the torque converter 16, and the automatic transmission 18 are all housed in a transmission case 36. The transmission case 36 is a split case made of aluminum die cast, for example, and is fixed to a non-rotating member such as a vehicle body.

The clutch K0 includes a cylindrical clutch drum 38, a cylindrical clutch hub 40 which is smaller in diameter than the clutch drum 38 and is concentrically provided with the clutch drum 38 so as to be rotatable relative to the clutch drum 38, and the clutch drum 38 and the clutch. A frictional engagement member 42 provided in an annular gap between the hub 40 and a clutch piston 44 that presses the frictional engagement member 42 in the direction of the axis C is provided. The clutch drum 38 is integrally fixed to the boss portion 30a of the rotor 30 of the electric motor MG, for example, by welding or the like, and can be rotated integrally with the rotor 30. The friction engagement member 42 is provided between a plurality of annular plate-like separators engaged with the clutch drum 38 so as not to rotate relative to the clutch drum 38, and is rotated between the plurality of separators and rotated relative to the clutch hub 40. And a plurality of annular plate-like friction plates engaged with each other.

In the clutch K0 thus configured, the friction engagement member 42 is pressed in the direction of the axis C by the clutch piston 44, and the separator and the friction plate are frictionally engaged with each other. The relative rotation between the clutch drum 38 and the clutch hub 40 is suppressed. That is, the friction engagement between the separator of the friction engagement member 42 and the friction plate allows the power transmission between the clutch drum 38 and the clutch hub 40. The clutch K0 is preferably a normally-closed (normally closed) clutch that is engaged when no command is output from the electronic control unit 58 described later.

The crankshaft 26 has an output end, that is, one end on the side of the electric motor MG, connected to a rotating shaft 48 that is rotated integrally with the clutch hub 40 of the clutch K0 via a drive plate 46 or the like. That is, the crankshaft 26 and the clutch hub 40 are connected via the drive plate 46 and the rotary shaft 48 so as to be rotated integrally around a common axis C. Further, a hydraulic pump 28 is connected to the pump impeller 16p of the torque converter 16, and the hydraulic pressure generated by the hydraulic pump 28 with the rotation of the pump impeller 16 is supplied to the hydraulic control circuit 34 as an original pressure. It has come to be supplied as.

Further, between the pump impeller 16p and the turbine impeller 16t of the torque converter 16, there is provided a lockup clutch LU that is directly connected so that the pump impeller 16p and the turbine impeller 16t are rotated together. ing. The lock-up clutch LU is controlled so that its engagement state is engaged (completely engaged), slip-engaged, or released (completely released) according to the hydraulic pressure supplied from the hydraulic control circuit 34. It has become. That is, the lockup clutch LU is provided in a power transmission path between the electric motor MG and the drive wheel 24, and corresponds to a second clutch that controls power transmission in the power transmission path in accordance with the engaged state.

The electric motor MG is integrally fixed to the transmission case 36 on the outer peripheral side of the rotary shaft 48 and the rotor 30 rotatably supported around the axis C by the transmission case 36. The stator 50 is provided. The rotor 30 has a slight gap between a cylindrical boss portion 30a rotatably supported by the transmission case 36 via a pair of bearings 52 and the stator 50 on the inner peripheral side of the stator 50. The rotor part 30b which has the some annular steel plate laminated | stacked on the axial center C direction in the state which spaced apart, and the connection part 30c which connects these boss | hub parts 30a and the rotor part 30b integrally are provided. The rotor 30 is connected to the inner periphery of the rotor portion 30b and is connected to the front cover 32 via a transmission member 54 that is integrally fixed to the front cover 32 by, for example, welding. The stator 50 is annularly wound around a core 50a in which a plurality of annular steel plates are respectively laminated in the direction of the axis C, and a part of the inner peripheral portion of the core 50a in the circumferential direction. A plurality of coils 50b provided continuously. The core 50a is integrally fixed to the transmission case 36 with bolts or the like at a plurality of locations in the circumferential direction.

The electric motor MG configured as described above is connected to a power storage device (not shown) such as a battery or a capacitor via an inverter 56 shown in FIG. 1, and the inverter 56 is controlled by an electronic control device 58 described later. Thus, the drive of the electric motor MG is controlled by adjusting the drive current supplied to the coil 50b. In other words, the output torque of the electric motor MG can be increased or decreased by controlling the inverter 56 by the electronic control unit 58. The output torque from the electric motor MG is output only to the torque converter 16 when the clutch K0 is disengaged (not engaged), but when the clutch K0 is engaged, the output torque A part is output to the torque converter 16 and the other part is output to the engine 12.

In the hybrid vehicle 10, for example, when shifting from EV traveling using the electric motor MG as a driving source for traveling to engine traveling or hybrid traveling using the engine 12 as a driving source, the engine is engaged by the clutch K0. 12 starts. That is, when the clutch K0 is slip-engaged or completely engaged, the engine 12 is rotationally driven by the torque for starting the engine transmitted through the clutch K0, whereby the engine rotational speed _NE is increased. The engine 12 is started by controlling engine ignition, fuel supply, and the like while being pulled up. At this time, compensation torque is generated by the electric motor MG, and generation of acceleration (deceleration G) in the longitudinal direction of the vehicle is suppressed. That is, the engine 12 is started by the torque obtained from the explosion energy by ignition and the torque obtained from the engagement energy by the clutch K0, that is, the engine starting torque transmitted through the clutch K0. This is done by being driven.

The hybrid vehicle 10 includes a control system as illustrated in FIG. The electronic control device 58 shown in FIG. 1 includes a so-called microcomputer having a CPU, a RAM, a ROM, an input / output interface, and the like. The CPU uses a temporary storage function of the RAM and stores it in the ROM in advance. By performing signal processing according to the stored program, the drive control of the engine 12, the drive control of the electric motor MG, the shift control of the automatic transmission 18, the engagement force control of the clutch K0, and the lock-up clutch LU Various controls such as engagement control are executed.

As shown in FIG. 1, the electronic control device 58 is supplied with various input signals detected by the sensors provided in the hybrid vehicle 10. For example, a signal representing the accelerator opening A _CC detected by the accelerator opening sensor 60, a signal indicative of the rotational speed (motor rotation speed) N _MG of the motor MG detected by motor rotation speed sensor 62, an engine rotational speed sensor A signal representing the rotational speed (engine rotational speed) N _E of the engine 12 detected by 64, a rotational speed (turbine rotational speed) N _T of the turbine impeller 16t of the torque converter 16 detected by a turbine rotational speed sensor 66. signal representative of the signal representing the vehicle speed V detected by the vehicle speed sensor 68, and a signal or the like representing the cooling water temperature T _W of the engine 12 detected by the water temperature sensor 70 is inputted to the electronic control unit 58. Here, the rotational speed N _MG of the motor MG detected by motor rotation speed sensor 62 is an input rotational speed of the torque converter 16, which corresponds to the rotational speed of the pump impeller 16p in the torque converter 16. The rotational speed _NT of the turbine impeller 16 t detected by the turbine rotational speed sensor 66 is an output rotational speed of the torque converter 16 and corresponds to an input rotational speed of the automatic transmission 18.

Further, various output signals are supplied from the electronic control device 58 to each device provided in the hybrid vehicle 10. For example, a signal supplied to the output control device 14 of the engine 12 for drive control of the engine 12, a signal supplied to the inverter 56 for drive control of the electric motor MG, a shift of the automatic transmission 18 A signal supplied to a plurality of electromagnetic control valves in the hydraulic control circuit 34 for control, a signal supplied to the electromagnetic control valves in the hydraulic control circuit 34 for controlling the engagement of the clutch K0, and the lock-up A signal or the like supplied to the electromagnetic control valve in the hydraulic control circuit 34 for engagement control of the clutch LU is supplied from the electronic control unit 58 to each part.

FIG. 3 is a functional block diagram for explaining a main part of the control function provided in the electronic control unit 58. The shift control means 80 shown in FIG. 3 executes shift control of the automatic transmission 18 based on the driving state (running state) of the hybrid vehicle 10 based on a predetermined relationship. For example, the vehicle speed V detected by the vehicle speed sensor 68 and the accelerator opening detected by the accelerator opening sensor 60 from a shift map 74 as shown in FIG. Based on the required driving force amount such as A _CC , the shift speed to be established in the automatic transmission 18 is determined, and the hydraulic pressure supplied to the automatic transmission 18 is controlled so that the shift speed is established. . Specifically, by controlling the operation (output hydraulic pressure) of each electronic control valve provided in the hydraulic control circuit 34, each hydraulic friction engagement device in the automatic transmission 18 is controlled from the hydraulic control circuit 34. Controls the hydraulic pressure supplied to the hydraulic actuator. Here, the driving force requirement amount is a value indicating the driving force for traveling required for the hybrid vehicle 10 determined according to the driver's operation, and values other than the accelerator opening degree A _CC include: A depression amount of an accelerator pedal (not shown), an opening of an electronic throttle valve (throttle opening θ _TH ), or the like may be used.

Hybrid drive control means 82 executes hybrid drive control in the hybrid vehicle 10. That is, by controlling the drive of the engine 12 via the output control device 14 and controlling the operation of the electric motor MG via the inverter 56, at least one of the engine 12 and the electric motor MG is driven for traveling. Drive control of the hybrid vehicle 10 as a source is performed. For example, the engine 12 is stopped and the EV traveling (motor traveling) mode exclusively using the electric motor MG as a driving source for traveling, the engine traveling mode exclusively using the engine 12 as a driving source for traveling, the engine 12 and the electric motor An EHV driving (hybrid driving) mode in which both MGs are used as driving sources for driving and regeneration (power generation) is performed by the electric motor MG according to the driving state is selectively established according to the driving state of the hybrid vehicle 10. Let

In the EV travel mode, the hybrid drive control means 82 performs travel control of the hybrid vehicle 10 exclusively using the electric motor MG as a drive source for travel. That is, the required output shaft torque is determined based on the accelerator opening degree A _cc and the vehicle speed V as the required driving force amount from the driving force map stored in advance, and the required charging shaft value is considered from the required output shaft torque. Calculate the required driving force. Then, the driving (output torque) of the electric motor MG is controlled so that the required driving force can be obtained. In this EV travel mode, the driving of the engine 12 is basically stopped and the clutch K0 is released (completely released). As a result, the power transmission path between the engine 12 and the electric motor MG is cut off, and no power is transmitted from the engine 12 to the lockup clutch 16 side. Conversely, from the lockup clutch 16 side to the engine 12. Torque transmission is not performed.

In the engine travel mode, the hybrid drive control means 82 performs travel control of the hybrid vehicle 10 exclusively using the engine 12 as a drive source for travel. That is, the target engine output is calculated so as to obtain the required driving force obtained as described above, and the optimum engine 12 that has been experimentally obtained and stored in advance so as to achieve both drivability and fuel efficiency. While driving the engine 12 along the fuel consumption rate curve (fuel consumption map, relationship), the drive of the engine 12 is controlled so that the engine rotational speed _NE and the engine torque at which the target engine output is obtained are obtained. In this engine running mode, the clutch K0 is engaged (completely engaged). Further, although the electric motor MG is idled, the electric motor MG may be operated so as to perform regeneration according to the traveling state.

In the EHV travel mode, the hybrid drive control means 82 performs travel control of the hybrid vehicle 10 using both the engine 12 and the electric motor MG as drive sources for travel. That is, the target engine output is calculated in consideration of transmission loss, auxiliary machine load, assist torque of the electric motor MG, etc. so that the required driving force required as described above can be obtained, thereby achieving both drivability and fuel efficiency. The engine rotational speed _NE and the engine output speed NE can be obtained while operating the engine 12 along the optimum fuel consumption rate curve (fuel consumption map, relationship) of the engine 12 that has been experimentally obtained and stored in advance. The drive of the engine 12 and the electric motor MG is controlled so that the engine torque is obtained. In this EHV traveling mode, the electric motor MG does not always have to be used as a driving source for traveling, and control such as idling or regenerative operation according to the traveling state of the hybrid vehicle 10 is performed. May be used.

The hybrid drive control means 82 controls regeneration (power generation) by the electric motor MG. That is, when it is determined that regeneration is to be performed based on the accelerator opening degree A _CC as the driving force requirement amount from a predetermined relationship, the operation is controlled so that regeneration is performed by the electric motor MG. The electric energy generated by the regeneration of the electric motor MG in this way is stored in a power storage device (not shown) via the inverter 56. When the electric motor MG is used as a drive source, electric energy is supplied from the power storage device to the electric motor MG via the inverter 56 to generate a driving force.

FIG. 4 is a diagram showing a shift map 74 used for shift determination of the automatic transmission 18 by the shift control means 74 and a switching map 76 used for travel mode switching determination by the hybrid control means 76. . The shift map 74 shown in FIG. 4 is an upshift line, that is, a low speed stage (a gear stage having a relatively large gear ratio) to a high speed stage (a gear stage having a relatively small gear ratio) among the shift lines used for the shift determination. Only the shift line for determining the shift is shown, and the downshift line, that is, the shift line for determining the shift from the high speed to the low speed is omitted. A shift line (1 → 2 upshift line) for determining a shift from the first speed to the second speed is a solid line, and a shift line (1 for determining a shift from the first speed to the second speed to the third speed). EV driving mode (→ 3 upshift line to 2 → 3 upshift line) is indicated by a one-dot chain line, and a shift line (3 → 4 upshift line) for determining a shift from the third speed to the fourth speed is indicated by a two-dot chain line. Switching lines for determining switching between the (EV region) and the EHV travel mode (EHV region) are indicated by broken lines.

As shown in FIG. 4, in the shift map 74 and the switching map 76, the shift line (2 → 3 upshift line) for determining the shift from the second speed to the third speed of the automatic transmission 18 is determined. A part of the switching line overlaps with a part of a switching line for determining switching from the EHV traveling mode to the EV traveling mode. In addition, a part of a shift line (3 → 4 upshift line) for determining a shift from the third speed to the fourth speed of the automatic transmission 18 and switching from the EHV travel mode to the EV travel mode are performed. A part of the determination switching line overlaps. That is, in the shift determination and the traveling mode switching determination, a part of each of the 2 → 3 upshift line and the 3 → 4 upshift line, and a switching line for determining switching from the EHV traveling mode to the EV traveling mode. It is stipulated to be shared with some. Here, in FIG. 4, in order to show the line types of the respective lines in an easy-to-understand manner, such shared portions are shown slightly shifted, but preferably the shift line and the switching line have the same relationship (coincidence). The Further, there may be a difference that can be regarded as substantially the same relationship in practical use. That is, the common use of the shift line and the switching line means a relationship in which the shift determination and the traveling mode switching determination are performed substantially in synchronization, for example, within a predetermined error range with reference to the shift line (FIG. 4). Then, if a switching line is defined for the vehicle speed and the accelerator opening error, it can be said that the shift line and the switching line are shared. This is the same in the following description.

In other words, in the shift map 74 and the switching map 76, the vehicle speed V and the accelerator opening detected by the vehicle speed sensor 68 are used because they are shared as the 2 → 3 upshift line and the EHV → EV switching line. Based on the accelerator opening degree A _CC detected by the sensor 60, the EV travel mode and the automatic transmission 18 are set to the third mode from the state in which the EHV travel mode and the automatic transmission 18 are in the second speed. It is determined that the transition to the state of speed is determined. Also, based on the relationship shared as the 3 → 4 upshift line and the EHV → EV switching line, based on the vehicle speed V detected by the vehicle speed sensor 68 and the accelerator opening degree A _CC detected by the accelerator opening degree sensor 60. The transition from the state in which the vehicle is in the EHV traveling mode and the automatic transmission 18 is in the third speed to the state in which the vehicle is in the EV traveling mode and the automatic transmission 18 is in the fourth speed is determined. It has been established.

In the shift map 74 and the switching map 76, a switching line for determining switching from the EV traveling mode to the HEV traveling mode while the automatic transmission 18 is maintained at the first speed is the EV. A higher driving force demand amount side (high accelerator opening) than the shift line (1 → 3 upshift line) for determining the shift from the first speed to the third speed of the automatic transmission 18 while maintaining the traveling mode. (Degree side). In addition, a switching line for determining switching from the EV traveling mode to the HEV traveling mode while the automatic transmission 18 is maintained at the fourth speed is maintained in the HEV traveling mode. It is determined on the lower driving force requirement side (low accelerator opening side) than the shift line (3 → 4 upshift line) for determining the shift from 18 third speed to fourth speed. Further, a part of the shift line of the shift map 74 shared with the switch line of the switch map 76, that is, a part of each of the 2 → 3 upshift line and the 3 → 4 upshift line, corresponds as the vehicle speed V increases. It is determined that the accelerator opening degree A _CC that is the driving force requirement amount is gradually decreased (monotonically decreased). In other words, in the plane coordinates having the vehicle speed V shown in FIG. 4 as the horizontal axis and the accelerator opening degree A _CC as the vertical axis, a portion of the shift line of the shift map 74 shared with the switching line of the switching map 76 is on the right. It is set so that it falls.

FIG. 5 is a diagram for explaining specific shift control and travel mode switching control using the shift map 74 and the switching map 76 shown in FIG. When the operation (1) shown in FIG. 5 is performed by the driver, that is, from the state where the vehicle is in the EHV traveling mode and the automatic transmission 18 is at the second speed, the accelerator pedal is stepped back with the vehicle speed being substantially constant ( When the operation of (accelerator on → accelerator off) is performed, the switching control from the EHV traveling mode to the EV traveling mode and the shifting control from the second speed to the third speed of the automatic transmission 18 are simultaneously determined or executed. .

FIG. 6 is a time chart showing an example of a change with time of the turbine rotation speed _NT and the engagement pressure of each hydraulic friction engagement element during the shift of the automatic transmission 18. In FIG. 6, the gripping of the hydraulic friction engagement element, that is, the so-called clutch-to-clutch shift is illustrated as an example. Respectively. As shown in FIG. 6, when the hydraulic frictional engagement element is changed during the shift of the automatic transmission 18, for example, the engagement pressure is actually increased from the time t1 when the first fill of the release side clutch is started. The automatic transmission 18 is in a substantially neutral state until time t2 when the ascent starts. That is, the power transmission path between the crankshaft 26 of the engine 12 and the differential gear device 20 is substantially cut off. In the control of the present embodiment, the transition from the EHV traveling mode to the EV traveling mode is executed while the automatic transmission 18 is in the substantially neutral state. That is, when the automatic transmission 18 is controlled to be shifted from the second speed to the third speed by the operation (1) shown in FIG. 5, the neutral state is established by changing the engagement element in the automatic transmission 18. By stopping the engine 12 in the meantime, it is possible to suitably suppress the transmission of shock due to the stop to the output side, that is, the output shaft of the automatic transmission 18 or the differential gear device 20 side, and robustness against shock. Can be improved. In particular, in the upshift from the low speed stage to the high speed stage, the high speed stage is changed after the turbine rotational speed _NT is lowered due to the engine stop while the automatic transmission 18 is in the substantially neutral state. Therefore, the robustness can be further improved by canceling the engine stop shock and the shift shock.

Further, when the driver performs the operation (2) shown in FIG. 5, that is, the EV travel mode and the automatic transmission 18 is in the first speed, the accelerator pedal is depressed, and the EHV travel mode. And after the shift to the state where the automatic transmission 18 is in the first speed is determined, the accelerator pedal is stepped back to be in the EV traveling mode and the automatic transmission 18 is in the third speed. Considering the case where the shift to the vehicle is judged, in the EV travel mode, after shifting from the relatively small accelerator opening degree A _CC to the EHV travel mode, the transition to the EV travel mode and the 1 → 3 upshift are executed again. Therefore, drivability can be improved by reducing the number of shifts. That is, since the number of shifts can be reduced compared to the mode in which the transition from the EHV travel mode to the EV travel mode is performed and the 1 → 2 upshift or the 2 → 3 upshift is continuously performed, the gear ratio (speed ratio) ) Is large and the sensitivity of the shock is high, that is, the shock can be reduced when the engine is stopped from the state where the automatic transmission 18 is in the first speed and is in the EHV traveling mode. Further, when the torque converter 16 is provided with a lock-up clutch LU as in the hybrid vehicle 10 of the present embodiment, a shock is generated by engaging the lock-up clutch LU during the shift of the automatic transmission 18. However, by reducing the number of shifts as described above, there is an advantage that such a restriction is reduced and the engagement area of the lockup clutch LU can be substantially enlarged.

FIG. 7 is a diagram showing another shift map 78 used for the shift determination of the automatic transmission 18 by the shift control means 74 and a switch map 76 used for the travel mode switching determination by the hybrid control means 76. It is. The shift map 78 shown in FIG. 7 shows only the downshift line, that is, the shift line for determining the shift from the high speed stage to the low speed stage among the shift lines used for the shift determination, and the upshift line, that is, the low speed stage. The shift line for determining the shift from the high speed to the high speed is omitted. Further, a shift line (2 → 1 downshift line) for determining a shift from the second speed to the first speed is a solid line, and a shift line (3 for determining a shift from the third speed to the second speed to the first speed). EV drive mode (→ 1 downshift line to 3 → 2 downshift line) is indicated by a one-dot chain line, and a shift line (4 → 3 downshift line) for determining a shift from the fourth speed to the third speed is indicated by a two-dot chain line. Switching lines for determining switching between the (EV region) and the EHV travel mode (EHV region) are indicated by broken lines.

As shown in FIG. 7, in the shift map 78 and the switching map 76, the shift line (3 → 2 downshift line) for determining the shift from the third speed to the second speed of the automatic transmission 18 is determined. A part of the switching line overlaps with a part of the switching line for determining switching from the EV traveling mode to the EHV traveling mode. Further, a part of a shift line (4 → 3 downshift line) for determining the shift from the fourth speed to the third speed of the automatic transmission 18 and switching from the EV travel mode to the EHV travel mode are performed. A part of the determination switching line overlaps. That is, in the shift determination and the traveling mode switching determination, a part of each of the 3 → 2 downshift line and the 4 → 3 downshift line, and a switching line for determining switching from the EV traveling mode to the EHV traveling mode. It is stipulated to be shared with some.

In other words, in the shift map 78 and the switching map 76, the vehicle speed V and the accelerator opening detected by the vehicle speed sensor 68 are used because they are shared as the 3 → 2 downshift line and the EV → EHV switching line. Based on the accelerator opening degree A _CC detected by the sensor 60, the EV driving mode and the automatic transmission 18 are in the EHV driving mode and the automatic transmission 18 is in the second state from the state where the automatic transmission 18 is in the third speed. It is determined that the transition to the state of speed is determined. Further, based on the relationship shared as the 4 → 3 downshift line and the EV → EHV switching line, the vehicle speed V detected by the vehicle speed sensor 68 and the accelerator opening degree A _CC detected by the accelerator opening degree sensor 60 are used. The transition from the state in which the vehicle is in the EV traveling mode and the automatic transmission 18 is in the fourth speed to the state in which the automatic transmission 18 is in the EHV traveling mode and the automatic transmission 18 is in the third speed is determined. It has been established.

In the shift control and the travel mode switching control using the shift map 78 and the switching map 76, as in the control using the shift map 74 and the switching map 76, the automatic transmission 18 is in a substantially neutral state. Then, the transition from the EV traveling mode to the EHV traveling mode is executed. That is, for example, when the shift from the EV travel mode to the EHV travel mode is performed in synchronization with the shift control from the third speed to the second speed of the automatic transmission 18, the engagement element in the automatic transmission 18 is grasped. By starting the engine 12 while the neutral state is established by replacement, the shock caused by the start is transmitted to the output side, that is, the output shaft of the automatic transmission 18 to the differential gear device 20 side. It can suppress suitably and can improve the robustness with respect to a shock. In particular, in the downshift from the high speed stage to the low speed stage, the low speed stage is changed after the turbine rotational speed _NT is increased due to the engine starting while the automatic transmission 18 is in the substantially neutral state. Therefore, the robustness can be further improved by canceling the engine start shock and the shift shock.

FIG. 8 is a flowchart for explaining a main part of the synchronous execution control of the shift control and the traveling mode switching control by the electronic control unit 58, and is repeatedly executed at a predetermined cycle.

First, in step (hereinafter step is omitted) S1, it is determined whether or not the vehicle travel mode is an EHV travel mode using the engine 12 and the electric motor MG as drive sources. If the determination at S1 is negative, the routine is terminated accordingly. If the determination at S1 is affirmative, whether or not the shift determination and the traveling mode switching determination are performed simultaneously at S2. That is, it is determined whether or not the shift of the automatic transmission 18 and the switching to the EV travel mode are determined based on the relationship shared as the shift line and the switching line. If the determination in S2 is negative, the routine is terminated accordingly. If the determination in S2 is affirmative, in S3, the transition from the EHV traveling mode to the EV traveling mode, that is, the engine. 12 stop control and shift control of the automatic transmission 18 are executed. Next, in S4, the switching of the driving mode and the shift control are completed, and this routine is ended accordingly. In the above control, S2 to S4 correspond to the operations of the shift control means 80 and the hybrid drive control means 82.

As described above, according to this embodiment, the engine 12, the electric motor MG functioning as a drive source, and the stepped gear that selectively establishes a plurality of shift speeds based on the traveling state of the vehicle from a predetermined shift line. In the control device of the hybrid vehicle 10 equipped with the automatic transmission 18 of the type, switching between the EHV traveling mode using the engine 12 and the electric motor MG as a driving source and the EV traveling mode exclusively using the electric motor MG as a driving source is performed. Since at least a part of the switching line for determination and at least a part of the shift line are shared, the stop control and the shift control of the engine 12 are executed synchronously, thereby generating a shock. It is possible to suitably prevent the control from becoming complicated. That is, in the hybrid vehicle 10 including the stepped automatic transmission 18, it is possible to provide the electronic control device 58 that reduces the shock when the traveling mode is switched.

Further, since at least part of the switching line for determining switching from the EHV traveling mode to the EV traveling mode and at least part of the upshift line among the shift lines are shared, Since the stop control of the engine 12 and the upshift control are executed synchronously, the occurrence of a shock can be more suitably suppressed.

Further, the shift line is determined so as to determine the shift stage based on the vehicle speed V and the accelerator opening degree A _CC as the required driving force, and the automatic transmission 18 is set to the first speed. A switching line for determining switching from the EV traveling mode to the HEV traveling mode while maintaining the automatic transmission 18 from the first speed to a higher speed is maintained while maintaining the EV traveling mode. For example, when the vehicle is in the EV travel mode and the automatic transmission 18 is at the first speed, the vehicle speed V is set to be higher than the shift line for determining the shift of the vehicle. When the accelerator is turned off and the accelerator is turned off, the stop control and the shift control of the engine 12 are executed synchronously, so that the occurrence of a shock can be suitably suppressed.

In addition, since the portion shared with the switching line in the shift line is determined so that the corresponding accelerator opening degree A _CC is gradually decreased as the vehicle speed V becomes higher, it is shared with the shift line and the switching line. Based on the practical relationship, the stop control and the shift control of the engine 12 are executed synchronously.

Subsequently, another preferred embodiment of the present invention will be described in detail with reference to the drawings. In the following description, parts common to the embodiments are denoted by the same reference numerals and description thereof is omitted.

FIG. 9 is a diagram conceptually showing the structure of a drive system according to another hybrid vehicle 90 to which the present invention is preferably applied. The hybrid vehicle 90 shown in FIG. 9 has a power transmission path between the crankshaft 26 of the engine 12 and the input shaft 92 of the automatic transmission 18 according to the engagement state. Is provided with a first clutch CL1. Further, in the automatic transmission 18, a power transmission path between the input shaft 92 and a drive shaft 94 which is an input shaft of the differential gear device 20 (an output shaft of the automatic transmission 18) is connected to the power transmission path. A second clutch CL2 is provided for controlling power transmission in the power transmission path according to the combined state. The rotor 30 of the electric motor MG is connected to the input shaft 92 of the automatic transmission 18.

The hybrid vehicle 90 configured as described above selectively establishes a plurality of shift stages based on the running state of the vehicle from the engine 12, the electric motor MG functioning as a drive source, and a predetermined shift line. A stepped automatic transmission 18 is provided, and an EHV traveling mode using the engine 12 and the electric motor MG as a driving source and an EV traveling mode exclusively using the electric motor MG as a driving source are selectively established. . That is, similarly to the hybrid vehicle 10 described above, there are problems such as complication of control at the time of switching the traveling mode, generation of shock due to stop control of the engine 12, and the like. Therefore, at least a part of the switching line for determining switching between the EHV traveling mode using the engine 12 and the electric motor MG as a driving source and the EV traveling mode exclusively using the electric motor MG, and at least the shift line. By configuring so that a part is shared, the stop control and the like of the engine 12 and the shift control are executed synchronously, it is possible to suppress the occurrence of shock and suitably prevent the control from becoming complicated. Can do.

FIG. 10 is a diagram conceptually showing the configuration of a drive system according to still another hybrid vehicle 100 to which the present invention is preferably applied. The hybrid vehicle 100 shown in FIG. 10 does not include the clutch K0 provided between the crankshaft 26 of the engine 12 and the electric motor MG in the hybrid vehicle 10 described above with reference to FIG. A shaft 26 is connected to the input shaft of the torque converter 16. Further, the rotor 30 of the electric motor MG is coupled to the crankshaft 26 of the engine 12.

The hybrid vehicle 100 configured as described above selectively establishes a plurality of shift stages based on the running state of the vehicle from the engine 12, the electric motor MG functioning as a drive source, and a predetermined shift line. A stepped automatic transmission 18 is provided, and an EHV traveling mode using the engine 12 and the electric motor MG as a driving source and an EV traveling mode exclusively using the electric motor MG as a driving source are selectively established. . That is, similarly to the hybrid vehicle 10 and the like described above, there are problems such as complicated control at the time of switching the traveling mode, occurrence of shock due to stop control of the engine 12, and the like. Therefore, at least a part of the switching line for determining switching between the EHV traveling mode using the engine 12 and the electric motor MG as a driving source and the EV traveling mode exclusively using the electric motor MG, and at least the shift line. By configuring so that a part is shared, the stop control and the like of the engine 12 and the shift control are executed synchronously, it is possible to suppress the occurrence of shock and suitably prevent the control from becoming complicated. Can do. In particular, as shown in FIG. 10, in the configuration in which the rotor 30 of the electric motor MG is connected to the crankshaft 26 of the engine 12, when the engine 12 is stopped at the time of transition from the EHV traveling mode to the EV traveling mode or the like. Although vibration may occur, by executing the stop control and the shift control of the engine 12 synchronously, it is possible to suppress the generation of vibration and realize a suitable engine stop.

FIG. 11 is a diagram conceptually showing the configuration of a drive system according to still another hybrid vehicle 110 to which the present invention is preferably applied. A hybrid vehicle 110 shown in FIG. 11 includes a planetary gear device 112 that functions as a differential unit between the crankshaft 26 of the engine 12 and the input shaft 92 of the automatic transmission 18, and the planetary gear device. The first electric motor MG1 and the second electric motor MG2 are connected to 112. That is, the rotor 30 of the first electric motor MG1 is connected to the sun gear S that is the first rotating element of the planetary gear unit 112, the crankshaft 26 of the engine 12 is connected to the carrier CA that is the second rotating element, The rotor 30 of the second electric motor MG2 is connected to a ring gear R that is a three-rotation element. In such a configuration, the operation state of the first electric motor MG1 is controlled by the inverter 56, whereby the differential state between the rotation speed of the carrier CA and the rotation speed of the ring gear R is controlled, and the planetary gear unit 112 is controlled. Functions as an electric differential section. In the hybrid vehicle 110, for example, the second electric motor MG2 functions as a driving source that generates driving force for traveling in the EV traveling mode.

The hybrid vehicle 110 configured as described above selectively selects a plurality of shift speeds based on the running state of the vehicle from the engine 12, the second electric motor MG2 functioning as a drive source, and a predetermined shift line. A stepped automatic transmission 18 to be established, and an EHV traveling mode using the engine 12 and the second electric motor MG2 as a driving source and an EV traveling mode exclusively using the second electric motor MG2 as a driving source. Selectively established. That is, similarly to the hybrid vehicle 10 and the like described above, there are problems such as complicated control at the time of switching the traveling mode, occurrence of shock due to stop control of the engine 12, and the like. Therefore, at least a part of a switching line for determining switching between the EHV traveling mode using the engine 12 and the second electric motor MG2 as a driving source and the EV traveling mode exclusively using the second electric motor MG2; By configuring so that at least a part of the shift line is shared, the stop control and the like of the engine 12 and the shift control are executed synchronously, so that the occurrence of shock can be suppressed and the control becomes complicated. It can prevent suitably.

The preferred embodiments of the present invention have been described above in detail with reference to the drawings. However, the present invention is not limited to these embodiments, and may be implemented in other modes.

For example, in the above-described embodiment, the hybrid vehicle 10 provided with the electric motor MG functioning as a drive source in the power transmission path between the engine 12 and the automatic transmission 18 has been described. For example, the present invention is applicable to a hybrid vehicle in which the automatic transmission 18 is provided in a power transmission path between the engine 12 and the front wheels, and the electric motor MG is connected to the rear wheels. It is preferably applied. That is, the present invention is widely applied to hybrid vehicles including an engine, an electric motor that functions as a drive source, and a stepped automatic transmission.

Further, the above-described embodiment includes the automatic transmission 18 that includes a plurality of hydraulic friction engagement devices and selectively establishes a plurality of shift stages according to engagement or release of the hydraulic friction engagement devices. The hybrid vehicle 10 and the like have been described. For example, a dual clutch transmission (Dual Clutch) having a synchronous mesh transmission (manual transmission) having a synchromesh mechanism and automatically shifting the synchronous mesh transmission. The present invention is also suitably applied to a hybrid vehicle having Transmission (DCT). In other words, the hybrid vehicle including the stepped automatic transmission that selectively establishes a plurality of shift speeds based on the running state of the vehicle from a predetermined shift line has the advantage of the present invention. .

Further, the shift map 74 and the switching map 76 shown in FIG. 4 and the like described in the above-described embodiment are prepared for the purpose of easily explaining the features of the present invention, and in practical terms, the vehicle characteristics, etc. It goes without saying that more detailed relationships are used accordingly. That is, the shift map and switching map used in the hybrid vehicle control device of the present invention are appropriately determined according to various designs and the like as long as they have a portion shared by a part of each of the shift line and the switching line. is there.

In addition, although not illustrated one by one, the present invention is implemented with various modifications within a range not departing from the gist thereof.

10, 90, 100, 110: Hybrid vehicle, 12: Engine, 14: Output control device, 1616: Torque converter, 16p: Pump impeller, 16t: Turbine impeller, 18: Automatic transmission, 20: Differential gear device , 22: axle, 24: drive wheel, 26: crankshaft, 28: hydraulic pump, 30: rotor, 30a: boss part, 30b: rotor part, 30c: coupling part, 32: front cover, 34: hydraulic control circuit, 36: Transmission case, 38: Clutch drum, 40: Clutch hub, 42: Friction engagement member, 44: Clutch piston, 46: Drive plate, 48: Rotating shaft, 50: Stator, 50a: Core part, 50b: Coil part , 52: bearing, 54: transmission member, 56: inverter, 58: electronic control unit, 60: accelerator opening sensor, 62: electric Rotational speed sensor, 64: Engine rotational speed sensor, 66: Turbine rotational speed sensor, 68: Vehicle speed sensor, 70: Water temperature sensor, 72: Storage device, 74, 78: Shift map, 76: Switching map, 80: Shift control means 82: Hybrid drive control means, 92: Input shaft, 94: Drive shaft, 112: Planetary gear device, CA: Carrier, CL1: First clutch, CL2: Second clutch, K0: Clutch, LU: Lock-up clutch, MG: electric motor, MG1: first electric motor, MG2: second electric motor, R: ring gear, S: sun gear

Claims

An hybrid vehicle comprising: an engine; an electric motor that functions as a drive source; and a stepped automatic transmission that selectively establishes a plurality of shift speeds based on a running state of the vehicle from a predetermined shift line. A control device,
At least a part of a switching line for determining switching between an EHV traveling mode using the engine and the electric motor as a driving source and an EV traveling mode exclusively using the electric motor as a driving source and at least a part of the shift line are shared. A hybrid vehicle control device.
The at least part of the switching line for determining switching from the EHV traveling mode to the EV traveling mode and at least a part of the upshift line among the shift lines are shared. Hybrid vehicle control device.
The shift line is determined so as to determine the shift stage based on a vehicle speed and a driving force request amount.
A switching line for determining the switching from the EV traveling mode to the HEV traveling mode while the automatic transmission is maintained at the first speed is the first transmission line that is maintained in the EV traveling mode. The control apparatus for a hybrid vehicle according to claim 1 or 2, wherein the control apparatus is defined on a higher driving force request amount side than a shift line for determining a shift from a speed to a higher speed.
The shift line is determined so as to determine the shift stage based on a vehicle speed and a driving force request amount.
4. The hybrid according to claim 1, wherein a portion of the shift line that is shared with the switching line is determined such that the corresponding driving force request amount is gradually decreased as the vehicle speed increases. 5. Vehicle control device.