JP2022157475A - Control device of vehicle - Google Patents

Abstract

To properly suppress a chip-in shock when two drive force sources of an engine and an electric motor can be used.SOLUTION: In a prescribed torque region of output torque of a preset drive force source in which a backlash reduction direction of a power transmission device is inverted when drive torque is changed to positive torque from negative torque, an engine and an electric motor are controlled so as to set the output torque of the drive force source to gradually-changing torque at which a rise gradient is set to a small value compared with the case that the output torque is out of a prescribed torque region, and a chip-in shock can be thereby easily suppressed when a vehicle is switched to a drive state from a driven state. Also, since the output torque of the engine is controlled in a state that the output torque of the electric motor is fixed so as to obtain the gradually-changing torque within the prescribed torque region, the output torque of the drive force source can be accurately controlled to the gradually-changing torque in the prescribed torque region entirely according to a change in the output torque of the engine.SELECTED DRAWING: Figure 4

Description

The present invention relates to a control device for a vehicle having an engine and an electric motor as driving force sources.

BACKGROUND ART A control device for a vehicle is well known that includes a driving force source including an engine and an electric motor, and a power transmission device that transmits output torque of the driving force source to driving wheels. For example, a motor control device for a hybrid vehicle described in Patent Document 1 is one of them. In Patent Document 1, when the driving torque is changed from negative to positive, the backlash between rotating members in a power transmission device, such as the backlash of gears, is reversed, resulting in tooth striking caused by reversing the direction of reducing the backlash. In order to suppress the so-called tip-in shock, it is disclosed that the drive torque is changed from negative to positive by the backlash reduction torque generated by the output torque of the electric motor.

JP 2015-89735 A

By the way, the technique described in Patent Document 1 is control of looseness torque when the engine is stopped, and it is assumed that the looseness elimination torque is realized by the output torque of the engine and the output torque of the electric motor while the engine is running. In addition, highly accurate torque control is required in order to reduce backlash while suppressing tip-in-shock. However, if you try to combine the output torque of the engine and the output torque of the electric motor to achieve the target torque for suppressing the tip-in shock, the difference in the communication delay of each will lead to the deviation of the command torque and the response delay of each actuator. Due to the difference in torque accuracy due to the difference in torque, there is a risk that the torque control cannot be performed with high accuracy when reducing backlash.

The present invention has been made against the background of the above circumstances, and its object is to be able to appropriately suppress tip-in shock when two driving force sources, an engine and an electric motor, can be used. An object of the present invention is to provide a control device for a vehicle.

The gist of the first invention is (a) control of a vehicle equipped with a driving force source including an engine and an electric motor, and a power transmission device for transmitting the output torque of the driving force source to the drive wheels. (b) within a predetermined torque region of the output torque of the driving force source, in which the looseness direction in the power transmission device is reversed when the driving torque is changed from negative torque to positive torque; and a driving force source control unit for controlling the engine and the electric motor so that the output torque of the driving force source is a gradually varying torque having a smaller rising gradient than outside the predetermined torque range. and (c) the driving force source control section controls the output torque of the engine while the output torque of the electric motor is fixed so as to realize the gradual change torque.

In a second aspect of the invention, in the vehicle control device according to the first aspect, the driving force source control unit, during execution of the gradual change control for realizing the gradual change torque, reduces the gradual change torque to set the required intake torque, which is a required value of the output torque of the engine controlled by adjusting the intake air amount of the engine, which is higher by a predetermined torque, and after reducing the required intake torque by ignition retardation control By setting the post-retarding required torque, which is the required value of the output torque of the engine, to the slow change torque, the output torque of the engine is controlled, and the required electric motor torque, which is the required value of the output torque of the electric motor, is set to zero. , the output torque of the electric motor is fixed.

In a third aspect of the invention, in the vehicle control device according to the second aspect, the driving force source control unit requests charging of a power storage device for charging electric power from the electric motor generated by the power of the engine. If there is, during execution of the gradual change control, the charging request torque, which is the required value of the output torque of the engine that realizes the charging request, is added to the gradual change torque by the predetermined torque amount. By setting the high required intake torque and setting the post-retarding required torque to a torque value obtained by adding the charging required torque to the gradual change torque, the output torque of the engine is controlled, and the required electric motor torque is controlled. is set as the charging request torque, the output torque of the electric motor is fixed.

In a fourth aspect of the invention, in the control device for a vehicle according to the third aspect, the driving force source control unit, while the gradual change control is being executed, sets the charging request torque to the gradual change control. It is to hold at the value at the start.

A fifth invention is the vehicle control device according to any one of the second invention to the fourth invention, wherein in the ignition retardation control, the driving force source control unit is configured to: To control the output torque of the electric motor so as to compensate for the torque difference between the post-retardation required torque and the output torque of the engine after the ignition retardation control when the required torque cannot be realized.

According to the first aspect of the invention, within a predetermined torque region of the output torque of the driving force source, which is predetermined in which the looseness direction in the power transmission device is reversed when the driving torque is changed from negative torque to positive torque, Since the engine and the electric motor are controlled so that the output torque of the driving force source has a gradually changing torque with a smaller rising gradient than outside the predetermined torque range, the vehicle changes from the driven state to the driving state. It is made easy to suppress tip-in shock when switching. Furthermore, since the output torque of the engine is controlled while the output torque of the electric motor is fixed so as to achieve a gradually changing torque within the predetermined torque region, the engine is driven exclusively by changes in the output torque of the engine within the predetermined torque region. The output torque of the power source is accurately controlled to a gradually changing torque. Therefore, tip-in-shock can be appropriately suppressed when two driving force sources, the engine and the electric motor, can be used.

Further, according to the second aspect, during execution of the gradual change control that realizes the gradual change torque, the required intake torque is set higher than the gradual change torque by a predetermined torque, and the ignition is retarded with respect to the requested intake torque. The output torque of the engine is controlled by setting the post-retarding required torque that has been reduced by the angle control to a gradual change torque, and the output torque of the electric motor is fixed by setting the required electric motor torque to zero. Therefore, within the predetermined torque range, the output torque of the driving force source is appropriately and precisely controlled to a gradually changing torque solely by the change in the output torque of the engine.

Further, according to the third aspect, when there is a request to charge the power storage device, during execution of the slow change control, an intake request that is higher than the torque value obtained by adding the charge request torque to the slow change torque by a predetermined torque. The torque is set, and the post-retarding required torque is set to a torque value obtained by adding the charging required torque to the gradual change torque, thereby controlling the output torque of the engine and setting the required electric motor torque to the charging required torque. As a result, the output torque of the electric motor is fixed, so that the charging request of the power storage device is realized, and the output torque of the driving force source is gradually changed within the predetermined torque range mainly due to the change in the output torque of the engine. is controlled with high precision.

Further, according to the fourth aspect, while the gradual change control is being executed, the required charging torque is held at the value at the start of the gradual change control. Even if V fluctuates, the output torque of the driving force source is accurately controlled to gradually change torque.

Further, according to the fifth aspect, when the post-retardation required torque cannot be realized in the ignition retardation control, the torque difference between the post-retardation required torque and the output torque of the engine after the ignition retardation control Since the output torque of the electric motor is controlled so as to compensate for , the output torque of the driving force source can be controlled to gradually change torque within the predetermined torque region with higher accuracy.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram for explaining a schematic configuration of a vehicle to which the present invention is applied, and is a diagram for explaining main parts of a control system and control functions for various controls in the vehicle; FIG. 5 is a diagram for explaining the execution of slow change control with high accuracy; FIG. 10 is a diagram for explaining the execution of slow change control with high accuracy when there is a request to charge the battery; 4 is a flow chart for explaining the main part of the control operation of the electronic control unit, and is a flow chart for explaining the control operation for appropriately suppressing tip-in-shock when two driving force sources, an engine and an electric motor, are available.

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

FIG. 1 is a diagram for explaining a schematic configuration of a vehicle 10 to which the present invention is applied, and is a diagram for explaining control functions and main parts of a control system for various controls in the vehicle 10. As shown in FIG. In FIG. 1, a vehicle 10 is a hybrid vehicle including an engine 12 and an electric motor MG, which are driving force sources SP for running. The vehicle 10 also includes drive wheels 14 and a power transmission device 16 provided in a power transmission path between the engine 12 and the drive wheels 14 .

The engine 12 is a known internal combustion engine such as a gasoline engine or a diesel engine. An engine control device 50 including a throttle actuator, a fuel injection device, an ignition device, and the like provided in the vehicle 10 is controlled by an electronic control device 90, which will be described later, to control the engine 12. The engine torque Te, which is the output torque of the engine 12, is controlled by the engine 12. is controlled.

The electric motor MG is a rotating electric machine having a function as a motor that generates mechanical power from electric power and a function as a generator that generates power from mechanical power, and is a so-called motor generator. Electric motor MG is connected to a battery 54 provided in vehicle 10 via an inverter 52 provided in vehicle 10 . The battery 54 is a power storage device that transfers electric power to and from the electric motor MG. In the electric motor MG, the MG torque Tm, which is the output torque of the electric motor MG, is controlled by controlling the inverter 52 by the electronic control unit 90, which will be described later. For example, when the rotation direction of the electric motor MG is the same rotation direction as the engine 12 is running, the MG torque Tm is a power running torque when the positive torque is on the acceleration side, and is a regenerative torque when the negative torque is on the deceleration side. be. The electric motor MG, for example, generates power from the power of the engine 12, and the battery 54 charges the electric power from the electric motor MG. Electric power is also synonymous with electrical energy when not specifically distinguished. The power is also synonymous with torque and force unless otherwise specified.

The power transmission device 16 includes a K0 clutch 20, a torque converter 22, an automatic transmission 24, etc. in a case 18, which is a non-rotating member attached to the vehicle body. K0 clutch 20 is a clutch provided between engine 12 and electric motor MG in a power transmission path between engine 12 and driving wheels 14 . Torque converter 22 is connected to engine 12 via K0 clutch 20 . Automatic transmission 24 is connected to torque converter 22 and is interposed in a power transmission path between torque converter 22 and drive wheels 14 . The power transmission device 16 includes a propeller shaft 28 connected to a transmission output shaft 26 which is an output rotating member of an automatic transmission 24, a differential gear 30 connected to the propeller shaft 28, and a gear 1 connected to the differential gear 30. A pair of drive shafts 32 and the like are provided. The power transmission device 16 also includes an engine connection shaft 34 that connects the engine 12 and the K0 clutch 20, an electric motor connection shaft 36 that connects the K0 clutch 20 and the torque converter 22, and the like.

The electric motor MG is connected to the electric motor connecting shaft 36 within the case 18 so as to be able to transmit power. In other words, the electric motor MG is connected to the power transmission path between the K0 clutch 20 and the torque converter 22 so that power can be transmitted. In other words, the electric motor MG is connected to the torque converter 22 and the automatic transmission 24 without the K0 clutch 20 so that power can be transmitted.

The torque converter 22 includes a pump impeller 22 a connected to an electric motor connecting shaft 36 and a turbine impeller 22 b connected to a transmission input shaft 38 which is an input rotating member of the automatic transmission 24 . The torque converter 22 is a hydrodynamic transmission device that transmits the driving force from the driving force source SP from the electric motor connecting shaft 36 to the transmission input shaft 38 via fluid. The torque converter 22 includes an LU clutch 40 as a direct clutch that connects the pump impeller 22a and the turbine impeller 22b, that is, connects the electric motor connecting shaft 36 and the transmission input shaft 38. The LU clutch 40 is a known lockup clutch.

The automatic transmission 24 is a known planetary gear type automatic transmission including, for example, one or a plurality of sets of planetary gears (not shown) and a plurality of engagement devices CB. The engagement device CB is, for example, a known hydraulic friction engagement device. Each engagement device CB changes its torque capacity CB torque Tcb by CB hydraulic pressure PRcb which is regulated hydraulic pressure supplied from the hydraulic control circuit 56, so that the engagement device CB is in an engaged state or a disengaged state. is switched between operating states or control states.

In the automatic transmission 24, the gear ratio (also referred to as gear ratio) γat (=AT input rotation speed Ni/AT output rotation speed No) is established by engaging any one of the engagement devices CB. is a stepped transmission in which one of a plurality of gear stages (also referred to as gear stages) is formed. The automatic transmission 24 switches between gear stages according to the driver's accelerator operation, the vehicle speed V, and the like, by an electronic control unit 90, which will be described later. The AT input rotation speed Ni is the rotation speed of the transmission input shaft 38 and the input rotation speed of the automatic transmission 24 . The AT input rotation speed Ni has the same value as the turbine rotation speed Nt, which is the output rotation speed of the torque converter 22 . The AT input rotation speed Ni can be represented by the turbine rotation speed Nt. The AT output rotation speed No is the rotation speed of the transmission output shaft 26 and the output rotation speed of the automatic transmission 24 .

The K0 clutch 20 is a hydraulic friction engagement device composed of, for example, a multi-plate or single-plate clutch. The K0 clutch 20 changes the K0 torque Tk0, which is the torque capacity of the K0 clutch 20, by the K0 hydraulic pressure PRk0, which is the regulated hydraulic pressure supplied from the hydraulic control circuit 56, so that the engaged state and the disengaged state are changed. Control state is switched.

In the vehicle 10, when the K0 clutch 20 is engaged, the engine 12 and the torque converter 22 are connected so as to be able to transmit power. On the other hand, when the K0 clutch 20 is released, power transmission between the engine 12 and the torque converter 22 is cut off. Since the electric motor MG is connected to the torque converter 22, the K0 clutch 20 functions as a clutch that connects and disconnects the engine 12 with the electric motor MG.

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 connection shaft 34 to the K0 clutch 20, the electric motor connection shaft 36, the torque converter 22, the automatic transmission 24, The power is transmitted to the drive wheels 14 through the propeller shaft 28, the differential gear 30, the drive shaft 32, and the like. The power output from the electric motor MG is transmitted from the electric motor connecting shaft 36 to the torque converter 22, the automatic transmission 24, the propeller shaft 28, the differential gear 30, the drive shaft 32, etc. regardless of the control state of the K0 clutch 20. The power is transmitted to the driving wheels 14 through successively. Thus, the power transmission device 16 transmits the driving force source torque Tsp, which is the output torque of the driving force source SP, to the driving wheels 14 . The driving force source torque Tsp is the total torque of the engine torque Te and the MG torque Tm.

The vehicle 10 includes a mechanical oil pump MOP 58, an electric oil pump EOP 60, a pump motor 62, and the like. The MOP 58 is connected to the pump impeller 22a, and is driven to rotate by the driving force source SP to discharge hydraulic oil OIL used in the power transmission device 16. As shown in FIG. The pump motor 62 is a motor dedicated to the EOP 60 for rotating the EOP 60 . The EOP 60 is rotationally driven by the pump motor 62 to discharge hydraulic oil OIL. Hydraulic oil OIL discharged from the MOP 58 and the EOP 60 is supplied to the hydraulic control circuit 56 . The hydraulic control circuit 56 supplies the CB hydraulic pressure PRcb, the K0 hydraulic pressure PRk0, etc., each of which is adjusted based on the hydraulic oil OIL discharged from the MOP 58 and/or the EOP 60 .

The vehicle 10 further includes an electronic control unit 90 that includes a control unit for the vehicle 10 . The electronic control unit 90 includes, for example, a so-called microcomputer having a CPU, a RAM, a ROM, and an input/output interface. Various controls of the vehicle 10 are executed by performing signal processing. The electronic control unit 90 includes computers for engine control, electric motor control, hydraulic control, etc., as required.

The electronic control unit 90 includes various sensors provided in the vehicle 10 (for example, the engine rotation speed sensor 70, the turbine rotation speed sensor 72, the output rotation speed sensor 74, the MG rotation speed sensor 76, the accelerator opening sensor 78, the throttle valve Various signals based on values detected by an opening sensor 80, an air flow meter 82, a brake switch 84, a battery sensor 86, an oil temperature sensor 88, etc. (for example, the engine rotation speed Ne, which is the rotation speed of the engine 12, the AT input rotation speed Ni , the AT output rotation speed No corresponding to the vehicle speed V, the MG rotation speed Nm which is the rotation speed of the electric motor MG, and the driver's accelerator operation amount representing the magnitude of the driver's acceleration operation. Accelerator opening .theta.acc, throttle valve opening .theta.th that is the opening of the electronic throttle valve, intake air amount Qair of the engine 12, and a signal indicating a state in which the brake pedal for operating the wheel brake is being operated by the driver. A brake-on signal Bon, a battery temperature THbat of the battery 54, a battery charge/discharge current Ibat, a battery voltage Vbat, a working oil temperature THoil which is the temperature of the working oil OIL in the hydraulic control circuit 56, etc.) are supplied.

From the electronic control device 90, various command signals (for example, engine Control command signal Se, MG control command signal Sm for controlling the electric motor MG, CB hydraulic control command signal Scb for controlling the engagement device CB, K0 hydraulic control command signals Sk0 and LU for controlling the K0 clutch 20 LU oil pressure control command signal Slu for controlling the clutch 40, EOP control command signal Seop for controlling the EOP 60, etc.) are respectively output.

The electronic control unit 90 includes driving force source control means, ie, a driving force source control section 92 , and shift control means, ie, a shift control section 94 , in order to implement various controls in the vehicle 10 .

The driving force source control unit 92 functions as engine control means, ie, an engine control unit 92a, for controlling the operation of the engine 12, and functions as an electric motor control unit, ie, an electric motor control unit 92b, for controlling the operation of the electric motor MG via the inverter 52. function, and hybrid control means, ie, a hybrid control section, for executing hybrid drive control by the engine 12 and the electric motor MG by means of these control functions.

The driving force source control unit 92 calculates the amount of driving demand for the vehicle 10 by the driver, for example, by applying the accelerator opening θacc and the vehicle speed V to the driving demand amount map. The required drive amount map is a relationship that is experimentally or design-experimentally obtained and stored, that is, a predetermined relationship. The required drive amount is, for example, the required drive torque Trdem at the drive wheels 14 . The required driving torque Trdem [Nm] is, in other words, the required driving power Prdem [W] at the vehicle speed V at that time. As the required driving amount, the required driving force Frdem [N] at the driving wheels 14, the required AT output torque at the transmission output shaft 26, and the like can be used. In the calculation of the drive demand amount, the AT output rotation speed No or the like may be used instead of the vehicle speed V. FIG.

The driving force source control unit 92 considers the transmission loss, the auxiliary load, the gear ratio γat of the automatic transmission 24, the chargeable power Win and the dischargeable power Wout of the battery 54, etc., so as to realize the required drive power Prdem. , an engine control command signal Se for controlling the engine 12 and an MG control command signal Sm for controlling the electric motor MG are output. The engine control command signal Se is, for example, a command value of the engine power Pe, which is the power of the engine 12 that outputs the engine torque Te at the engine rotation speed Ne at that time. The MG control command signal Sm is, for example, a command value for the power consumption Wm of the electric motor MG that outputs the MG torque Tm at the MG rotational speed Nm at that time.

The chargeable power Win of the battery 54 is the maximum power that can be input that defines the limit of 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 that defines the limit of 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 unit 90 based on, for example, the battery temperature THbat and the battery charge amount SOC. The battery charge amount SOC is a charge state value [%] of the battery 54 that indicates the state of charge corresponding to the charge amount of the battery 54, and is calculated by the electronic control unit 90 based on, for example, the battery charge/discharge current Ibat and the battery voltage Vbat. be done.

The driving force source control unit 92 sets the driving mode to the motor driving (=EV driving) mode when the required driving torque Trdem can be covered only by the output of the electric motor MG. In the EV traveling mode, the driving force source control unit 92 performs EV traveling in which the driving force is output only from the electric motor MG of the driving force source SP in the disengaged state of the K0 clutch 20 . On the other hand, when the required drive torque Trdem cannot be met without using at least the output of the engine 12, the driving force source control unit 92 sets the driving mode to the engine driving mode, that is, the hybrid driving (=HV driving) mode. In the HV running mode, the driving force source control unit 92 performs engine running, ie, HV running, in which driving force is output from at least the engine 12 of the driving force source SP while the K0 clutch 20 is engaged. On the other hand, even when the required driving torque Trdem can be covered only by the output of the electric motor MG, the drive force source control unit 92 controls the battery charge amount SOC to be less than the engine start threshold value SOCest or the warm-up of the engine 12 or the like. If necessary, the HV running mode is established. The engine start threshold SOCest is a predetermined threshold for determining that the battery charge amount SOC is such that it is necessary to forcibly start the engine 12 and charge the battery 54 .

The shift control unit 94 determines the shift of the automatic transmission 24 using, for example, a shift map having a predetermined relationship, and outputs a CB hydraulic control command signal for executing shift control of the automatic transmission 24 as necessary. Scb is output to the hydraulic control circuit 56 . The shift map is a predetermined relationship having a shift line for judging the shift of the automatic transmission 24 on two-dimensional coordinates having, for example, the vehicle speed V and the required driving torque Trdem as variables. In the shift map, the AT output rotational speed No may be used instead of the vehicle speed V, and the required driving force Frdem, the accelerator opening θacc, the throttle valve opening θth, etc. may be used instead of the required driving torque Trdem. can be

Here, when the required driving torque Trdem is increased, the driving torque Tr may be switched from the negative torque at which the vehicle 10 is in the driven state to the positive torque at which the vehicle 10 is in the driving state. In this case, since the direction in which the looseness between the parts constituting the power transmission device 16 is reduced is reversed, if the looseness is suddenly reduced, a tip-in shock may occur due to the looseness. The driving state of the vehicle 10 is a state in which the driving wheels 14 are rotated by the torque output from the driving force source SP. The driven state of the vehicle 10 is a state in which the torque input from the drive wheels 14 rotates the rotating members of the power transmission device 16 and the like. The driving force source control section 92 has a control function of suppressing abrupt elimination of backlash and suppressing tip-in-shock when the direction of backlash is reversed.

Specifically, when the required driving torque Trdem is increased from negative torque to positive torque, the driving force source control unit 92 changes the driving force source torque Tsp to The engine 12 and the electric motor MG are controlled so that the slowly changing torque Tspsl has a small value of the rising gradient compared to the outside of SPsl. The backlash elimination torque region SPsl is a predetermined torque region of the driving force source torque Tsp determined in advance in which the backlash elimination direction in the power transmission device 16 is reversed when the drive torque Tr is changed from negative torque to positive torque. That is, the backlash elimination torque region SPsl is a predetermined torque region of the driving force source torque Tsp that realizes a backlash striking point where the actual driving torque Tr is zero and a region of the driving torque Tr near the backlash striking point. . In this embodiment, the torque region in which the backlash elimination direction in the power transmission device 16 is reversed is set by the driving force source torque Tsp instead of the driving torque Tr. The driving force source torque Tsp is the torque on the electric motor connecting shaft 36 or the transmission input shaft 38 for realizing the driving torque Tr. The gradual change torque Tspsl is a predetermined rising gradient of the driving force source torque Tsp for suppressing rapid backlash reduction when the backlash reduction direction is reversed. The rising gradient of the driving force source torque Tsp outside the backlash reduction torque region SPsl is, for example, when the driving force source torque Tsp rises to achieve the final attainment torque of the required driving torque Trdem or when the final attainment torque is reached. is set by a predetermined upper limit when approaching the driving force source torque Tsp for realizing

By the way, in order to reduce backlash while suppressing tip-in-shock, it is necessary to control the gradual change torque Tspsl with high accuracy within the backlash reduction torque region SPsl. However, if an attempt is made to achieve the target slowly changing torque Tspsl by combining the engine torque Te as the driving force source torque Tsp and the MG torque Tm, the difference in communication delay between the engine control command signal Se and the MG control command signal Sm and the Due to the difference in response delay between the engine control device 50 and the inverter 52, there is a possibility that the slow change torque Tspsl cannot be controlled accurately. For example, when the engine torque Te rises, the estimation accuracy of the engine torque Te is poor due to the response delay, and the estimated value of the engine torque Te is set higher than the actual value of the engine torque Te. Since the requested value has a relatively high realization accuracy, if the requested value of the MG torque Tm is set based on the target value of the driving force source torque Tsp and the estimated value of the engine torque Te, the requested value of the MG torque Tm becomes a negative torque. , the actual driving force source torque Tsp may swing toward the negative torque side.

Therefore, the driving force source control section 92 controls the engine torque Te while the MG torque Tm is fixed so as to realize the slowly changing torque Tspsl.

FIG. 2 is a diagram for explaining accurate execution of the gradual change control CTspsl that realizes the gradual change torque Tspsl. In FIG. 2, at time t1a, when the vehicle 10 is in the driven state, the static target driving force source torque Tspts indicated by the two-dot chain line Aa changes from negative torque to positive torque due to the accelerator operation by the driver. indicates the point in time when the The static target driving force source torque Tspts is set as a target value of the driving force source torque Tsp for realizing the final attainment torque of the driving torque Trdem requested by the driver. A dynamic target driving force source torque Tsptd indicated by a thick solid line Ba is set for the static target driving force source torque Tspts. The dynamic target driving force source torque Tsptd is, for example, a target value of the driving force source torque Tsp set as a first-order lag function in step response with respect to the static target driving force source torque Tspts. However, the dynamic target driving force source torque Tsptd is set to a gradual change torque Tspsl within the backlash elimination torque region SPsl indicated by the region between the lower limit torque Tllim and the upper limit torque Tulim (see time t2a-t3a). ). The period during which the gradual change torque Tspsl is set is a net looseness elimination period during which the direction of looseness elimination in the power transmission device 16 is reversed. This net backlash elimination period is the time during which the dynamic target driving force source torque Tsptd stays in the backlash elimination torque region SPsl. Since torque transmission in the power transmission device 16 requires torque to overcome each gear loss and friction, the backlash elimination torque region SPsl is set on the positive side of the zero point.

In FIG. 2, the required intake torque Tebs indicated by the solid line Ca is set in order to achieve the dynamic target driving force source torque Tsptd, for example, with the engine torque Te by controlling the throttle valve opening θth. The required intake torque Tebs is, for example, a required value of the engine torque Te that is controlled by adjusting the intake air amount Qair of the engine 12, and a rough torque for forming the slowly changing torque Tspsl may be set. Specifically, if the required intake torque Tebs is too large, there will be more cases where the gradual change torque Tspsl cannot be formed by the ignition retardation control CTsd of the engine 12, while if it is too small, there is a risk that the gradual change torque Tspsl cannot be formed. , the target torque is set to be higher than the slowly changing torque Tspsl by a predetermined torque Tspf. It is set to a value that does not greatly deviate from the dynamic target driving force source torque Tsptd in the backlash reduction torque region SPsl. The predetermined torque Tspf is a predetermined torque value that enables the gradual change torque Tspsl to be formed by, for example, the ignition retardation control CTsd. The ignition retardation control CTsd of the engine 12 is one of torque reduction controls for reducing the engine torque Te by retarding the ignition timing of the engine 12 . Regarding the initial response variation of the engine torque Te controlled by adjusting the intake air amount Qair of the engine 12 due to the required intake torque Tebs, the influence is suppressed by, for example, ensuring a sufficient net looseness reduction period.

In FIG. 2, a post-retarding required torque Tesd indicated by a thick dashed line Ea is set, which is a required value of the engine torque Te after being reduced by the ignition retarding control CTsd with respect to the intake required torque Tebs. The ignition retardation control CTsd is executed when, for example, when the vehicle 10 is in the driven state with the accelerator off, the static target driving force source torque Tspts reaches the backlash reduction torque region SPsl from the negative side due to the driver turning on the accelerator. is started (see time t1a). At this time, if the dynamic target driving force source torque Tsptd is used to determine the start of the ignition retardation control CTsd, the timing with the accelerator is shifted, or the actual engine torque Teact is faster than the dynamic target driving force source torque Tsptd. Since a sudden change in the engine torque Te cannot be suppressed when the engine starts up, the static target driving force source torque Tspts is used to determine whether to start the ignition retardation control CTsd. The post-retarding demand torque Tesd is such that the lower limit torque Tllim of the backlash elimination torque region SPsl is reached during the period from the start of the ignition retardation control CTsd until the dynamic target driving force source torque Tsptd reaches the backlash elimination torque region SPsl. is set (see time t1a-t2a). This is because even if the actual engine torque Teact rises rapidly, it is guarded by the ignition retardation control CTsd so that it does not exceed the lower limit torque Tllim of the backlash reduction torque region SPsl. Further, the post-retarding demand torque Tesd is the dynamic target driving force source torque Tsptd during the period from when the dynamic target driving force source torque Tsptd exceeds the lower limit torque Tllim of the backlash elimination torque area SPsl to when it exceeds the upper limit torque Tulim of the backlash elimination torque area SPsl. target driving force source torque Tsptd, that is, the gradual change torque Tspsl (see time t2a-t3a). The ignition retardation control CTsd is executed so that the actual engine torque Teact after execution of the ignition retardation control CTsd becomes the gradual change torque Tspsl. Thus, during execution of the gradual change control CTspsl, the driving force source torque Tsp is precisely controlled to the gradual change torque Tspsl solely by the change in the engine torque Te. Therefore, the MG torque Tm is not required during execution of the slow change control CTspsl, so the required electric motor torque, ie, the required MG torque Tmdem, which is the required value of the MG torque Tm, is basically set to zero. Further, when the dynamic target driving force source torque Tsptd exceeds the upper limit torque Tulim of the backlash reduction torque region SPsl, the post-retardation demand torque Tesd is gradually reduced by the amount of torque reduction by the ignition retardation control CTsd, and the ignition retardation Preparations for terminating the control CTsd are executed (see time t3a-t4a). As a result, deterioration of drivability due to a sudden change in torque is suppressed during the preparation for termination of the ignition retardation control CTsd. Further, the ignition retardation control CTsd is completely terminated when the post-retardation required torque Tesd exceeds the actual engine torque Teact in consideration of the continuity of the actual engine torque Teact (see time t4a). Note that the post-retardation request torque Tesd may be guarded by the engine lower limit torque at which the engine torque Te can be realized so that the retardation request is not made to a region where the engine torque Te cannot be realized. Further, in order to prevent the ignition retardation control CTsd from being terminated because the dynamic target driving force source torque Tsptd does not exceed the upper limit torque Tulim of the backlash reduction torque region SPsl, the ignition retardation control CTsd is set to a predetermined retardation time. If this continues, the ignition retardation control CTsd may be terminated. This predetermined retardation time is, for example, a predetermined backup timer for forcibly ending the ignition retardation control CTsd.

In this manner, the driving force source control unit 92 sets the intake demand torque Tebs higher than the gradual change torque Tspsl by the predetermined torque Tspf during execution of the gradual change control CTspsl, and the post-retarding demand torque Tesd is set to the gradual change torque. The engine torque Te is controlled by setting Tspsl, and the MG torque Tm is fixed by setting the required MG torque Tmdem to zero.

If the amount of torque reduction by the ignition retardation control CTsd deviates from the target due to some defect in the engine 12 or the like, the post-retardation required torque Tesd cannot be realized. In this case, the torque difference between the post-retarding required torque Tesd and the engine torque Te after execution of the ignition retarding control CTsd may be compensated for by power running or power generation of the electric motor MG. For example, when the amount of torque reduction by the ignition retardation control CTsd is smaller than the target, the amount of torque reduction that could not be realized is recovered by charging the battery 54 by the power generation of the electric motor MG. In this manner, when the post-retardation required torque Tesd cannot be realized in the ignition retardation control CTsd, the driving force source control unit 92 determines the difference between the post-retardation required torque Tesd and the engine torque Te after the ignition retardation control CTsd. MG torque Tm is controlled to compensate for the torque difference. For example, the driving force source control section 92 controls the MG torque Tm based on the actual retardation amount in the ignition retardation control CTsd. The amount of compensation by the electric motor MG that becomes the required MG torque Tmdem is only the torque reduction amount that could not be realized by the ignition retardation control CTsd. Even if the MG torque Tm is restricted by Nm or the like, the gradual change torque Tspsl is easily achieved by exclusively controlling the engine torque Te.

FIG. 3 is a diagram for explaining how the gradual change control CTspsl is accurately executed when there is a request to charge the battery 54. In FIG. The gradual change control CTspsl of FIG. 3 is mainly different from the gradual change control CTspsl of FIG. 2 in that there is a request to charge the battery 54. Differences will be mainly described. In FIG. 3, at time t1b, when the vehicle 10 is in the driven state, the static target driving force source torque Tspts indicated by the two-dot chain line Ab changes from negative torque to positive torque due to the accelerator operation by the driver. indicates the point in time when the A dynamic target driving force source torque Tsptd indicated by a thick solid line Bb is set for the static target driving force source torque Tspts.

In FIG. 3, a request to charge the battery 54 that charges the electric power from the electric motor MG is made before time t1b. Therefore, the requested intake torque Tebs indicated by the solid line Cb is added with the requested charge torque Techg, which is the requested value of the engine torque Te that realizes the charge request for the battery 54 (see arrow Fa). That is, the required intake torque Tebs indicated by the solid line Cb is set on the positive side by the required charging torque Techg relative to the required intake torque Tebs indicated by the solid line Ca in FIG. Specifically, in the net backlash elimination period, the required intake torque Tebs in FIG. For example, when the actual engine torque Teact when the ignition retardation control CTsd indicated by the solid line Db is not performed, and the charge request torque Techg is added, is reduced by the charge request torque Techg, the backlash reduction torque It is set to a value that does not greatly deviate from the dynamic target driving force source torque Tsptd in the region SPsl. The charge request for the battery 54 is made, for example, when the battery charge amount SOC becomes less than the engine start threshold value SOCest, and is set as the charge request torque Techg for the engine 12 . Therefore, the input power of the battery 54 at the time of charging request, that is, the charging power [W] is based on the engine rotation speed Ne and the charging request torque Techg at that time.

In FIG. 3, the ignition retardation control CTsd is such that when the vehicle 10 is in the driven state with the accelerator off, the static target driving force source torque Tspts shifts from the negative side to the backlash reduction torque region SPsl by turning on the accelerator by the driver. It is started when it reaches (see time t1b), and in the ignition retardation control CTsd, the post-retardation required torque Tesd indicated by the thick broken line Eb is set. The post-retardation demand torque Tesd reaches the lower limit torque Tllim of the backlash elimination torque area SPsl during the period until the dynamic target driving force source torque Tsptd reaches the backlash elimination torque area SPsl after the start of the ignition retardation control CTsd. A torque value obtained by adding the required charging torque Techg (see arrow Fb) is set (see time t1b-t2b). Further, the post-retarding demand torque Tesd is slowed during the period from when the dynamic target driving force source torque Tsptd exceeds the lower limit torque Tllim of the backlash elimination torque area SPsl to when it exceeds the upper limit torque Tulim of the backlash elimination torque area SPsl. It is set to a torque value obtained by adding the required charging torque Techg (see arrows Fb, Fc, and Fd) to the changing torque Tspsl (see time t2b-time t3b). The ignition retardation control CTsd is executed so that the actual engine torque Teact after execution of the ignition retardation control CTsd becomes a torque obtained by adding the required charge torque Techg to the slow change torque Tspsl. The charging request torque Techg is maintained at the charging request torque Techg at the start of the ignition retardation control CTsd during the period from the start of the ignition retardation control CTsd until the dynamic target driving force source torque Tsptd exceeds the upper limit torque Tulim. (see arrows Fa, Fb, Fc, Fd). Therefore, the required charging torque Techg is maintained at the required charging torque Techg at the start of the gradual change control CTspsl during execution of the gradual change control CTspsl. During execution of the gradual change control CTspsl, the MG torque Tm may be a torque value that the electric motor MG recovers the required charge torque Techg by generating power. Specifically, it is set to the charging request torque Techg, that is, the differential torque between the dynamic target driving force source torque Tsptd (=gradual change torque Tspsl) and the post-retarding request torque Tesd. Thus, during execution of the gradual change control CTspsl, the driving force source torque Tsp is precisely controlled to the gradual change torque Tspsl solely by the change in the engine torque Te. Further, when the dynamic target driving force source torque Tsptd exceeds the upper limit torque Tulim of the backlash reduction torque region SPsl, the post-retardation demand torque Tesd is gradually reduced by the amount of torque reduction by the ignition retardation control CTsd (time t3b- See t4b time). Further, the ignition retardation control CTsd takes into consideration the continuity of the MG torque Tm and the continuity of the actual engine torque Teact, and when the post-retardation required torque Tesd exceeds the dynamic engine torque Tebsd and the actual engine torque Teact, complete (see time t4b). The dynamic engine torque Tebsd is, for example, a torque value set as a function of a first-order lag system in step response with respect to the required intake torque Tebs (see dashed line H). In FIG. 3, the torque reduction amount by the ignition retardation control CTsd is, for example, the differential torque between the post-retardation required torque Tesd and the dynamic engine torque Tebsd (see shaded portion I). In this case, the post-retarding required torque Tesd is set to the required value of the engine torque Te after the dynamic engine torque Tebsd is reduced by the ignition retarding control CTsd. The required MG torque Tmdem indicated by the shaded portion G is the differential torque between the dynamic target driving force source torque Tsptd and the post-retarding required torque Tesd during the period in which the torque reduction amount by the ignition retardation control CTsd is gradually reduced. (see t3b-t4b). Further, the required MG torque Tmdem indicated by the hatched portion G is set to the differential torque between the dynamic target driving force source torque Tsptd and the dynamic engine torque Tebsd after the ignition retardation control CTsd is completed (at time t4b). see below). Considering continuity with the required MG torque Tmdem before execution of the ignition retardation control CTsd, the required MG torque Tmdem during the execution of the ignition retardation control CTsd is calculated as follows. It is set by the difference torque (=Tsptd-MIN(Tesd, Tebsd)) between the smaller one of the post-request torque Tesd and the dynamic engine torque Tebsd. This ensures the continuity of the required MG torque Tmdem both when the ignition retardation control CTsd is started and when it ends.

In this way, when there is a charge request for the battery 54, the driving force source control unit 92 controls, during execution of the gradual change control CTspsl, that the charge request torque Techg is higher than the predetermined torque value obtained by adding the gradual change torque Tspsl. By setting the required intake torque Tebs higher by Tspf and setting the post-retarding required torque Tesd to a torque value obtained by adding the charging required torque Techg to the gradual change torque Tspsl, the engine torque Te is controlled and the required MG torque Tmdem is set as the charging request torque Techg, the MG torque Tm is fixed. Further, the driving force source control section 92 holds the required charging torque Techg at the value at the start of the gradual change control CTspsl during execution of the gradual change control CTspsl.

More specifically, driving force source control unit 92 determines whether the running mode is the HV running mode. When the driving force source control unit 92 determines that the driving mode is the HV driving mode, the driving force source control unit 92 sets the static target driving force source torque Tspts, the dynamic target driving force source torque Tsptd, the required intake torque Tebs, and the dynamic engine torque. Tebsd, required MG torque Tmdem, etc. are set, and the engine 12 and the electric motor MG are controlled. At this time, when there is a request to charge the battery 54, the driving force source control unit 92 takes into consideration the charging request torque Techg.

The driving force source control unit 92 determines whether or not the static target driving force source torque Tspts has reached the backlash reduction torque region SPsl from the negative side due to the accelerator being turned on by the driver. When the driving force source control unit 92 determines that the static target driving force source torque Tspts has reached the backlash reduction torque region SPsl from the negative side, the driving force source control unit 92 sets the post-retarding required torque Tesd, and performs the ignition retarding control CTsd. to execute the slow change control CTspsl.

FIG. 4 is a flowchart for explaining the main part of the control operation of the electronic control unit 90, and is a control for appropriately suppressing tip-in shock when two driving force sources SP, the engine 12 and the electric motor MG, can be used. 4 is a flow chart explaining the operation, for example, iteratively executed.

In FIG. 4, each step in the flow chart corresponds to the function of the driving force source control section 92 . In step (hereinafter, step is omitted) S10, it is determined whether or not the driving mode is the HV driving mode. If the determination in S10 is negative, this routine is terminated. If the determination in S10 is affirmative, in S20 static target driving force source torque Tspts, dynamic target driving force source torque Tsptd, required intake torque Tebs, dynamic engine torque Tebsd, required MG torque Tmdem, etc. are set. , the engine 12 and the electric motor MG are controlled. At this time, if there is a request to charge the battery 54, the required charging torque Techg is added. Next, in S30, it is determined whether or not the static target driving force source torque Tspts has reached the backlash reduction torque region SPsl from the negative side by turning on the accelerator by the driver. If the determination in S30 is negative, this routine is terminated. When the determination in S30 is affirmative, in S40, the post-retarding required torque Tesd is set, the ignition retarding control CTsd is executed, and the gradual change control CTspsl is executed.

As described above, according to the present embodiment, within the backlash-removing torque region SPsl, the driving force source torque Tsp is the slowly changing torque Tspsl having a smaller rising gradient than outside the backlash-removing torque region SPsl. Since the engine 12 and the electric motor MG are controlled in this manner, tip-in shock can be easily suppressed when the vehicle 10 is switched from the driven state to the driving state. Further, the engine torque Te is controlled while the MG torque Tm is fixed so as to realize the gradual change torque Tspsl within the backlash reduction torque region SPsl. The driving force source torque Tsp is accurately controlled to the gradual change torque Tspsl. Therefore, tip-in-shock can be appropriately suppressed when two driving force sources SP, the engine 12 and the electric motor MG, can be used.

Further, according to the present embodiment, while the gradual change control CTspsl is being executed, the required intake torque Tebs is set higher than the gradual change torque Tspsl by the predetermined torque Tspf, and the post-retarding required torque Tesd is set to the gradual change torque Tspsl. The engine torque Te is controlled by setting the required MG torque Tmdem to zero, and the MG torque Tm is fixed. Due to the change, the driving force source torque Tsp is appropriately and precisely controlled to the slowly changing torque Tspsl.

Further, according to the present embodiment, when there is a charge request for the battery 54, during execution of the slow change control CTspsl, the charge request torque Techg is higher than the torque value obtained by adding the slow change torque Tspsl by the predetermined torque Tspf. The required intake torque Tebs is set, and the post-retarding required torque Tesd is set to a torque value obtained by adding the charging required torque Techg to the gradual change torque Tspsl, thereby controlling the engine torque Te and increasing the required MG torque Tmdem. Since the MG torque Tm is fixed by setting it to the charging request torque Techg, the charging request for the battery 54 is realized, and the driving force source is controlled exclusively by the change in the engine torque Te within the backlash reduction torque region SPsl. Torque Tsp is accurately controlled to gradual change torque Tspsl.

Further, according to the present embodiment, while the gradual change control CTspsl is being executed, the required charging torque Techg is held at the value at the start of the gradual change control CTspsl. Even if the charging request fluctuates, the driving force source torque Tsp is accurately controlled to the gradual change torque Tspsl.

Further, according to the present embodiment, when the post-retardation required torque Tesd cannot be realized in the ignition retardation control CTsd, the torque between the post-retardation required torque Tesd and the engine torque Te after the ignition retardation control CTsd Since the MG torque Tm is controlled so as to compensate for the difference, the driving force source torque Tsp is more accurately controlled to the gradual change torque Tspsl within the backlash reduction torque region SPsl.

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

For example, in the above-described embodiment, when the LU clutch 40 is in the fully engaged state of lockup, if the tip-in shock is greater than when it is not locked up, the gradual change control CTspsl is accurately executed. This is useful control when the LU clutch 40 is locked up.

Further, in the above-described embodiment, the automatic transmission 24 is a planetary gear type automatic transmission, but it is not limited to this aspect. The automatic transmission 24 may be a synchronous mesh parallel twin-shaft automatic transmission including a known DCT (Dual Clutch Transmission), a known belt-type continuously variable transmission, or the like. Alternatively, the automatic transmission 24 does not necessarily have to be provided. Also, the engine 12 may be an engine having a supercharger. In short, the present invention can be applied to any vehicle provided with a driving force source that includes an engine and an electric motor, and a power transmission device that transmits the output torque of the driving force source to drive wheels.

Further, in the above-described embodiment, the torque converter 22 is used as the hydrodynamic transmission device, but the present invention is not limited to this aspect. For example, instead of the torque converter 22, another hydrodynamic transmission such as a fluid coupling that does not amplify torque may be used as the hydrodynamic transmission. Alternatively, the hydrodynamic transmission device does not necessarily have to be provided, and may be replaced with, for example, a starting clutch.

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

10: Vehicle 12: Engine 14: Drive Wheel 16: Power Transmission Device 54: Battery (Power Storage Device)
90: Electronic control device (control device)
92: Driving force source control unit MG: Electric motor SP: Driving force source

Claims (5)

A control device for a vehicle comprising a driving force source including an engine and an electric motor, and a power transmission device for transmitting output torque of the driving force source to drive wheels,
Within a predetermined torque range of the output torque of the driving force source, which is predetermined in which the looseness direction in the power transmission device is reversed when the driving torque is changed from negative torque to positive torque, the output torque of the driving force source is is a gradual change torque with a smaller rising gradient than outside the predetermined torque range, and
A control device for a vehicle, wherein the driving force source control unit controls the output torque of the engine while the output torque of the electric motor is fixed so as to realize the slowly changing torque. The driving force source control unit controls the output torque of the engine by adjusting the intake air amount of the engine, which is higher than the gradual change torque by a predetermined torque during the gradual change control for realizing the gradual change torque. set the required intake torque, which is the required value of the required intake torque, and set the post-retarding required torque, which is the required value of the output torque of the engine after the required intake torque is reduced by the ignition retardation control, to the gradual change torque. By doing so, the output torque of the engine is controlled, and the output torque of the electric motor is fixed by setting the required electric motor torque, which is the required value of the output torque of the electric motor, to zero. Item 1. The vehicle control device according to item 1. The driving force source control unit realizes the charging request during execution of the gradual change control when there is a charging request for a power storage device for charging electric power from the electric motor generated by the power of the engine. The required intake torque is set to be higher than the torque value obtained by adding the charging required torque, which is the required value of the output torque of the engine, to the gradual change torque by the predetermined torque, and the post-retarding required torque is set to the gradual change torque. The output torque of the engine is controlled by setting the torque value obtained by adding the charging request torque, and the output torque of the electric motor is fixed by setting the request electric motor torque to the charging request torque. The vehicle control device according to claim 2, characterized by: 4. The control device for a vehicle according to claim 3, wherein the driving force source control unit holds the required charging torque at a value at the start of the gradual change control while the gradual change control is being executed. . When the post-retardation required torque cannot be realized in the ignition retardation control, the driving force source control unit controls the torque difference between the post-retardation required torque and the output torque of the engine after the ignition retardation control. 5. The control device for a vehicle according to claim 2, wherein the output torque of said electric motor is controlled so as to compensate for .

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