JP2023024171A - Control device for hybrid vehicle - Google Patents

Abstract

To provide a control device for a hybrid vehicle, capable of suppressing a reduction in travelable distance if there occurs a predetermined abnormality in which an internal combustion engine cannot be started by using an electric motor and an engagement device.SOLUTION: A hybrid vehicle 10 includes an engine 12 and an electric motor MG as a driving force source for traveling, a clutch K0 for connecting/disconnecting power transmission between the engine 12 and the electric motor MG, and a starter motor 70 for starting the engine 12. When receiving a start request for a driving force source PG for traveling, an electronic control device 100 for the hybrid vehicle 10 uses the starter motor 70 to start the engine 12 if there is detected, before the start request, a predetermined abnormality in which the engine 12 cannot be started by using the electric motor MG and the clutch K0.SELECTED DRAWING: Figure 1

Description

The present invention provides a hybrid vehicle comprising an internal combustion engine and an electric motor that are driving force sources for running, an engagement device that connects and disconnects power transmission between the internal combustion engine and the electric motor, and a starter motor that starts the internal combustion engine. Regarding the control device.

A control device for a hybrid vehicle comprising: an internal combustion engine and an electric motor as driving force sources for running; an engagement device for connecting and disconnecting power transmission between the internal combustion engine and the electric motor; and a starter motor for starting the internal combustion engine. A method of starting an internal combustion engine by cranking the internal combustion engine using an electric motor and an engagement device is known. For example, the one described in Patent Document 1 is it. The method described in Patent Document 1 also describes starting the internal combustion engine using a starter motor.

JP 2017-159680 A

By the way, in the hybrid vehicle described in Patent Document 1, when receiving a request to start the driving force source for driving, the vehicle may be set in a driving mode in which the driving force for driving is output only from the electric motor so that the vehicle can run. In this case, if a predetermined abnormality has occurred in which the internal combustion engine cannot be started using the electric motor and the engagement device, the electric motor and the engagement device are not engaged during driving in a driving mode in which driving force for driving is output only from the electric motor. It is not possible to start the internal combustion engine with the coupling device. As a result, the vehicle can travel only for the amount of charge actually stored in the battery that supplies electric power to the electric motor, which may significantly reduce the travelable distance.

SUMMARY OF THE INVENTION The present invention has been made against the background of the above circumstances, and its object is to solve the problem when a predetermined abnormality has occurred that prevents an internal combustion engine from being started using an electric motor and an engagement device. It is an object of the present invention to provide a control device for a hybrid vehicle capable of suppressing a decrease in travelable distance.

The gist of the first invention is an internal combustion engine and an electric motor as driving force sources for running, an engagement device for connecting and disconnecting power transmission between the internal combustion engine and the electric motor, and a starter motor for starting the internal combustion engine. and a control device for a hybrid vehicle, wherein a predetermined abnormality that prevents the internal combustion engine from being started using the electric motor and the engagement device when a request to start the driving power source for running is received. is detected before the start request, the starter motor is used to start the internal combustion engine.

According to the hybrid vehicle control apparatus of the first aspect of the invention, when a request to start the driving force source for running is received, the predetermined abnormality that prevents the internal combustion engine from being started using the electric motor and the engagement device occurs. If the start request has been detected before, the starter motor is used to start the internal combustion engine. In this manner, when a predetermined abnormality that prevents the internal combustion engine from being started using the electric motor and the engagement device is detected before the start request is issued, the internal combustion engine is started using the starter motor. Since the hybrid vehicle is driven by the driving force for driving output from the started internal combustion engine, the possible driving distance is not limited to the amount of charge actually stored in the battery that supplies electric power to the electric motor. A decrease in the possible distance is suppressed.

According to the hybrid vehicle control device of the second invention, in the first invention, (a) when the predetermined abnormality is detected, the detection of the predetermined abnormality is stored; When the start request is received and it is stored that the predetermined abnormality has been detected, the internal combustion engine is started using the starter motor. For example, in some cases, the time required to detect a predetermined abnormality is longer than the time required for activation of the driving force source for running in response to a request for activation. Even in such a case, the fact that the predetermined abnormality has been detected is stored in advance. When a start request is received, start control of the internal combustion engine can be quickly executed using the starter motor. This suppresses deterioration of drivability.

1 is a schematic configuration diagram of a hybrid vehicle equipped with an electronic control device according to an embodiment of the present invention, and a functional block diagram showing main parts of control functions for various controls in the hybrid vehicle; FIG. FIG. 2 is an example of a flow chart for explaining the control operation of the electronic control unit shown in FIG. 1; FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following examples, the drawings are appropriately simplified or modified, and the dimensional ratios, shapes, etc. of each part are not necessarily drawn accurately.

FIG. 1 is a schematic configuration diagram of a hybrid vehicle 10 (hereinafter simply referred to as "vehicle 10") including an electronic control unit 100 according to an embodiment of the present invention, and control functions for various controls in the vehicle 10. It is a functional block diagram showing the main part of.

The vehicle 10 includes an engine 12 and an electric motor MG as a driving force source PG for running, and a power transmission device 16 provided in a power transmission path PT between the engine 12 and the driving wheels 14 . Vehicle 10 is a hybrid vehicle. The vehicle 10 also includes an inverter 52, a hydraulic control circuit 54, an EOP 56 that is an electric oil pump, a main battery 60, a system main relay 62, an auxiliary battery 66, a DC/DC converter 68, a starter motor 70, and an electronic control unit 100. Prepare.

Engine 12 is a well-known internal combustion engine. An engine control device 50 including a throttle actuator, a fuel injection device, an ignition device, etc. provided in the vehicle 10 is controlled by an electronic control device 100, which will be described later. [Nm] is controlled. In this specification, torque, driving force, power, and power are synonymous unless they are specifically distinguished. The engine 12 corresponds to the "internal combustion engine" in the present invention.

The power transmission device 16 is arranged in a case 18, which is a non-rotating member attached to the vehicle body, to input rotation of an engine connection shaft 20, a clutch K0, an electric motor connection shaft 22, a torque converter 24, and an automatic transmission 28 in this order from the engine 12 side. An AT input shaft 26, an automatic transmission 28, etc., which are members, are provided. The power transmission device 16 includes a differential gear 32 connected to an AT output shaft 30 that is an output rotating member of the automatic transmission 28, a pair of drive shafts 34 connected to the differential gear 32, and the like.

The engine connecting shaft 20 is a member that connects the engine 12 and the clutch K0, and is, for example, a crankshaft. A flywheel 12a is attached to the engine connecting shaft 20 so as not to be relatively rotatable.

The electric motor MG is a so-called motor generator having, for example, a function as a motor that generates mechanical power from electrical energy (motor function) and a function as a generator that generates electrical energy from mechanical power (generator function). is. Note that the electric motor MG corresponds to the "electric motor" in the present invention.

A clutch K0 is provided between an engine connection shaft 20 connected to the engine 12 and an electric motor connection shaft 22 connected to the rotor of the electric motor MG. The clutch K0 is an engagement device capable of connecting and disconnecting power transmission between the engine 12 and the electric motor connecting shaft 22, and is, for example, a wet multi-plate hydraulic friction engagement device. When clutch K0 is engaged, clutch K0 enables power transmission between engine 12 and electric motor MG. When the clutch K0 is released, the clutch K0 disconnects power transmission between the engine 12 and the electric motor MG. When the clutch K0 is brought into a semi-engaged state, i.e., a slip-engaged state, the clutch K0 allows the transmission torque capacity (engagement force of the clutch K0) based on the slip-engaged state to increase the torque between the engine 12 and the electric motor MG. Enables power transmission. Note that the clutch K0 corresponds to the "engagement device" in the present invention.

Electric motor MG is rotationally driven by electric power stored in main battery 60 and outputs driving force for running hybrid vehicle 10 . Further, the electric motor MG generates electric power using driving force for traveling input from the engine 12 via the clutch K0, or converts the driven force input from the driving wheel 14 side into electric power through regeneration. The generated electric power charges the main battery 60 via the inverter 52 and the system main relay 62 .

Inverter 52 is a power supply circuit provided between electric motor MG and main battery 60 and controlled by electronic control unit 100 to convert direct current into alternating current or convert alternating current into direct current. For example, the inverter 52 converts the direct current supplied from the main battery 60 into alternating current and outputs it to the electric motor MG to drive it, or converts the alternating current generated by the electric motor MG into direct current and outputs it to the main battery 60. do.

The starter motor 70 is a motor that starts the engine 12, and is a well-known motor that can crank the engine 12 by meshing with, for example, a ring gear engraved on the outer peripheral portion of the flywheel 12a.

The main battery 60 is a chargeable/dischargeable secondary battery such as a lithium ion battery or a nickel metal hydride battery. Main battery 60 is a first battery that is mainly used to supply electric power for driving electric motor MG and to charge electric power generated by electric motor MG through regeneration. The auxiliary battery 66 is, for example, a chargeable/dischargeable secondary battery such as a lead-acid battery or a lithium-ion battery. Auxiliary battery 66 is a second battery that is mainly used to supply electric power to auxiliary equipment (starter motor 70, engine control device 50, etc.). The main battery 60 has a higher battery voltage Vbat than the auxiliary battery 66 because of the difference in usage. For example, the auxiliary battery 66 has a voltage of 12 [V], while the main battery 60 has a higher voltage.

Main battery 60 is connected to inverter 52 via system main relay 62 . The system main relay 62 is, for example, a mechanical relay that can be switched between an open state (disconnected state) and a closed state (connected state) by the electronic control unit 100 . When system main relay 62 is closed, power can be transferred between main battery 60 and inverter 52 . When system main relay 62 is opened, power can not be transferred between main battery 60 and inverter 52 .

The DC/DC converter 68 is a power supply circuit that is provided between the power line 64 that connects the inverter 52 and the system main relay 62 and the auxiliary battery 66 and steps up or down DC. For example, the DC/DC converter 68 steps down the voltage supplied from the main battery 60 to the power line 64 to charge the auxiliary battery 66 with direct current having a voltage lower than that of the main battery 60, or supplies it from the auxiliary battery 66. The supplied direct current is stepped up to output a higher voltage direct current than the auxiliary battery 66 to the power line 64 .

Torque converter 24 is a known torque converter. The torque converter 24 includes a pump impeller connected to the electric motor connecting shaft 22, a turbine impeller connected to the AT input shaft 26, and a lockup clutch 40 that directly connects the pump impeller and the turbine impeller. . The torque converter 24 is a hydrodynamic transmission device capable of transmitting the driving force for driving output from the driving force source PG (engine 12, electric motor MG) from the electric motor connecting shaft 22 to the AT input shaft 26 via fluid. Vehicle 10 includes MOP 42, which is a mechanical oil pump. The MOP 42 is connected to the pump impeller and is rotationally driven by the drive power source PG (the engine 12 and the electric motor MG) to discharge hydraulic oil OIL used in the power transmission device 16 .

The EOP 56 is a well-known oil pump that can be driven by the rotation of the EOP drive motor 58 independently of the rotation of the engine 12 and the electric motor MG, which are the drive power source PG. The EOP drive motor 58 is a well-known electric motor, and the rotational speed of the EOP drive motor 58 is controlled by controlling an inverter (not shown) by the electronic control unit 100 . The EOP 56 is rotated by an EOP drive motor 58 and discharges hydraulic oil OIL used in the power transmission device 16 .

The automatic transmission 28 is a well-known automatic transmission that changes the speed of the driving force input to the AT input shaft 26 from the driving force source PG (the engine 12 and the electric motor MG) and outputs it to the AT output shaft 30. , for example, a planetary gear type or constant mesh type parallel shaft type stepped transmission, or a belt type or power roller type continuously variable transmission. The automatic transmission 28 is controlled by a hydraulic control circuit 54 controlled by the electronic control unit 100 so that a desired gear ratio γat is formed from among different gear ratios γat. In this embodiment, the automatic transmission 28 is a known planetary gear type automatic transmission including a plurality of sets of planetary gear devices and a plurality of transmission engagement devices CB. Each gear shift engagement device CB is fully engaged and partially engaged by regulating the hydraulic pressure supplied from the hydraulic control circuit 54 to the hydraulic actuators that control the connection/disengagement state of the gear shift engagement device CB. Connection/disconnection states such as a connected state and a released state are switched. In the automatic transmission 28, the gear ratio (also referred to as gear ratio) γat (=AT input rotation speed Ni [rpm]/AT output rotation speed) is changed by engagement of any one of the gearshift engagement devices CB. No [rpm]) of a plurality of gear stages (also referred to as gear stages) are formed.

The differential gear 32 receives driving force for running transmitted from the AT output shaft 30 of the automatic transmission 28, and transmits equal driving torque to the pair of drive shafts 34 while allowing an appropriate rotational speed difference. It is a well-known differential gear.

The hydraulic control circuit 54 uses the hydraulic pressure of the hydraulic oil OIL discharged from the MOP 42 and the EOP 56 as a source pressure, and supplies necessary hydraulic oil OIL to each part in the case 18 . For example, the hydraulic control circuit 54 generates hydraulic pressure for controlling connection/disengagement of the clutch K0, hydraulic pressure for shift control of the automatic transmission 28, and hydraulic pressure for connection/disconnection control of the lockup clutch 40 of the torque converter 24. 18 to each hydraulic actuator.

In the power transmission device 16, when the clutch K0 is engaged, the driving force for running output from the engine 12 is transmitted from the engine connecting shaft 20 to the clutch K0, the electric motor connecting shaft 22, the torque converter 24, the automatic transmission. 28, a differential gear 32, a drive shaft 34, and the like in order to the drive wheels 14. As shown in FIG. The driving force for running that is output from the electric motor MG is sequentially transmitted from the electric motor connecting shaft 22 through the torque converter 24, the automatic transmission 28, the differential gear 32, the drive shaft 34, and the like, regardless of whether the clutch K0 is engaged or disengaged. It is transmitted to the drive wheels 14 .

The vehicle power switch 94 is, for example, an automatic return push button switch that is disposed near the driver's seat and operated to switch the power supply state of the vehicle 10 .

For example, the power supply state of the vehicle 10 is switched to an activation state in which the vehicle can run by pressing the vehicle power switch 94 in conjunction with stepping on a brake pedal (not shown). When the vehicle power switch 94 is switched to the activated state, the power switch signal SWon is output and the electric motor MG or the engine 12 is brought into a state capable of outputting a driving force for running, that is, the power switch signal SWon is turned on and It is in a drivable state. In this embodiment, the activation request for the traveling driving force source PG is the pressing operation of the vehicle power switch 94 to bring it into the activated state. The activation request is a request to make the vehicle 10 ready for running.

For example, by pressing the vehicle power switch 94 without stepping on a brake pedal (not shown), the power is turned on (IG-ON state) to enable the vehicle to travel, and the power for vehicle travel is turned off. In addition, the power is partially turned on (ACC-ON state, IG-OFF state) to enable operation of some functions of the vehicle 10, such as an audio device and a car navigation device (not shown), by turning on the power that is not related to vehicle running. state) and a vehicle power supply off state (ALL-OFF state) in which all power supplies are off (ALL-OFF state). When the vehicle 10 is stopped, the vehicle power source switch 94 is pressed to turn off the vehicle power source, thereby stopping the driving force source PG, that is, the vehicle is no longer capable of running.

In the vehicle 10, one of the BEV driving mode, the engine driving mode, and the HEV driving mode can be selected. The BEV driving mode is a driving mode in which BEV (Battery Electric Vehicle) driving is performed using only the electric motor MG as a driving force source among the driving force sources PG for driving by controlling the power running of the electric motor MG with the engine 12 stopped. is. The engine driving mode is a driving mode in which the clutch K0 is engaged and only the engine 12 of the driving force source PG is used as the driving force source. The HEV travel mode is a travel mode in which the clutch K0 is engaged and HEV (Hybrid Electric Vehicle) travel is performed using both the engine 12 and the electric motor MG of the travel drive power source PG as the drive power sources.

Which one of the BEV driving mode, the engine driving mode, and the HEV driving mode is used for driving the vehicle 10 is switched by, for example, a driving force source switching map. The driving force source switching map is a relation in which the driving modes are predetermined in two-dimensional coordinates with variables such as the vehicle speed V [km/h] and the required driving torque Trdem [Nm]. In the low vehicle speed region where the vehicle speed V is relatively low and the required drive torque Trdem is relatively low (=region where the accelerator opening θacc is relatively low) where the engine efficiency generally declines, the BEV driving mode is selected. It is said that On the other hand, in the high vehicle speed region where the vehicle speed V is relatively high, or in the region where the required driving torque Trdem is relatively high (=the region where the accelerator opening degree θacc is relatively high), the engine running mode or the HEV running mode is selected. be done. The BEV running mode is applied when the SOC [%] of the state of charge of the main battery 60 (the ratio of the amount of charge actually stored to the predetermined full charge capacity) is equal to or greater than a predetermined engine start threshold. be. In other words, when the state-of-charge value SOC of the main battery 60 is less than the engine start threshold, there is no area in the driving force source switching map in which the BEV running mode is selected, and the engine running mode or the HEV running mode is selected for all. It is the same as being defined as an area that The engine start threshold is a predetermined threshold for determining the state of charge value SOC at which it is necessary to forcibly start engine 12 and charge main battery 60 .

The electronic control unit 100 includes, for example, a so-called microcomputer having a CPU, a RAM, a ROM, and an input/output interface. Various controls of the vehicle 10 are executed by performing signal processing. The electronic control unit 100 includes computers for engine control, electric motor control, hydraulic control, etc., as required. The electronic control device 100 corresponds to the "control device" in the present invention.

The electronic control unit 100 includes various sensors provided in the vehicle 10 (for example, an engine rotation speed sensor 80, a turbine rotation speed sensor 82, an output rotation speed sensor 84, an electric motor rotation speed sensor 86, an accelerator opening sensor 88, a throttle valve Equivalent to various signals (for example, engine rotation speed Ne [rpm] which is the rotation speed of engine 12, AT input rotation speed Ni [rpm]) based on detection values by opening sensor 90, battery sensor 92, vehicle power switch 94 AT output rotation speed No [rpm] corresponding to the vehicle speed V, electric motor rotation speed Nmg [rpm] that is the rotation speed of the electric motor MG, driving that represents the magnitude of the driver's acceleration operation Accelerator opening θacc [%], which is the accelerator operation amount of the user, throttle valve opening θth [%], which is the opening of the electronic throttle valve, battery temperature THbat [°C] of the main battery 60, and battery charge/discharge current Ibat [A ], the battery voltage Vbat [V], and the power switch signal SWon that is output when the vehicle power switch 94 is switched to the activated state by the driver, etc.) are input.

From the electronic control unit 100, each device provided in the vehicle 10 (for example, the engine control unit 50, the inverter 52, the hydraulic control circuit 54, the EOP drive motor 58, the system main relay 62, the DC/DC converter 68, etc.). Command signals (for example, an engine control signal Se for controlling the engine 12, an electric motor control signal Smg for controlling the electric motor MG, a shift control signal Sat for controlling the shift engagement device CB, and for controlling the clutch K0 K0 control signal Sk0, LU control signal Slu for controlling lockup clutch 40, EOP control signal Seop for controlling EOP 56, relay control signal Ssmr for controlling opening/closing of system main relay 62, DC/DC A converter control signal Scon for controlling the voltage conversion of the converter 68, etc.) are respectively output.

The electronic control unit 100 functionally includes a hybrid control unit 102 , a start control unit 104 , a clutch control unit 106 , a shift control unit 108 and an abnormality detection unit 110 .

The hybrid control unit 102 functionally includes an engine control unit 102a that controls the operation of the engine 12, and an electric motor control unit 102b that controls the operation of the electric motor MG via the inverter 52. and hybrid drive control by the electric motor MG.

The hybrid control unit 102 calculates the amount of driving demand for the vehicle 10 by the driver, for example, by applying the actual accelerator opening θacc and the vehicle speed V to the driving demand amount map. The required drive amount map is a map in which the relationship between the accelerator opening θacc and the vehicle speed V and the required drive amount is predetermined and stored experimentally or by design. The required drive amount is, for example, the required drive torque Trdem at the drive wheels 14 . In other words, the required drive torque Trdem is the required drive power Prdem [W] at the vehicle speed V at that time. As the required driving amount, the required driving force Frdem [N] at the driving wheels 14, the required output torque at the AT output shaft 30, and the like can be used. In calculating the drive demand amount, the AT output rotation speed No or the like may be used instead of the vehicle speed V. FIG.

The hybrid control unit 102 considers the transmission loss, auxiliary load, gear ratio γat of the automatic transmission 28, chargeable power Win [W] and dischargeable power Wout [W] of the main battery 60, etc., and determines the required driving power. An engine control signal Se for controlling the engine 12 and an electric motor control signal Smg for controlling the electric motor MG are output so as to realize Prdem. The engine control signal Se is, for example, a command value of the engine power Pe [W], which is the power of the engine 12 that outputs the engine torque Te at the engine rotation speed Ne at that time. The motor control signal Smg is, for example, a command value for the power consumption Wm [W] of the motor MG that outputs the motor torque Tmg [Nm] at the motor rotation speed Nmg at that time.

The chargeable power Win of the main battery 60 is the maximum power that can be input that defines the limit of the input power of the main battery 60 and indicates the input limit of the main battery 60 . The dischargeable power Wout of the main battery 60 is the maximum power that can be output that defines the limit of the output power of the main battery 60 and indicates the output limit of the main battery 60 . The chargeable power Win and dischargeable power Wout of the main battery 60 are calculated by the electronic control unit 100 based on the battery temperature THbat and the state of charge value SOC of the main battery 60, for example.

Hybrid control unit 102 controls vehicle 10 in a driving mode (BEV driving mode, engine driving mode, HEV driving mode) according to the state of vehicle 10 . For example, the driving mode according to the state of the vehicle 10 is selected by the driving force source switching map described above.

The engine control unit 102a controls the engine torque Te so as to achieve the amount of drive required for the vehicle 10. FIG. The electric motor control unit 102b controls the electric motor torque Tmg so as to achieve the amount of drive required for the vehicle 10. FIG. Specifically, in the BEV traveling mode, the electric motor control unit 102b controls the electric motor torque Tmg so as to achieve the required driving torque Trdem. In the engine running mode, the engine control unit 102a controls the engine torque Te so as to achieve the entire required drive torque Trdem, and the electric motor control unit 102b controls the excess of the engine torque Te with respect to the required drive torque Trdem. In some cases, the motor torque Tmg is controlled so that the excess power is used to generate power. In the HEV running mode, the engine control unit 102a controls the engine torque Te so as to achieve a part of the required driving torque Trdem, and the electric motor control unit 102b controls the engine torque Te to be insufficient for the required driving torque Trdem. The motor torque Tmg is controlled so as to compensate for the torque.

The shift control unit 108 determines the shift of the automatic transmission 28 using, for example, a shift map, and outputs a shift control signal Sat for executing shift control to the hydraulic control circuit 54 as necessary. The shift map is a predetermined relation having a shift line for judging the shift of the automatic transmission 28 on two-dimensional coordinates having, for example, the vehicle speed V and the required drive 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. Also good.

From now on, the case where the vehicle power switch 94 is operated by the driver to issue a request to activate the driving force source PG while the driving force source PG is stopped will be described.

The activation control unit 104 functionally includes an activation request determination unit 104a, an abnormality determination unit 104b, and an activation method determination unit 104c.

Activation request determination unit 104a determines whether or not a request to activate driving force source PG for traveling has been received. For example, the activation request determination unit 104a determines whether or not a request for activation of the traveling driving force source PG has been received based on whether or not the power switch signal SWon is in the ON state. Specifically, when the vehicle power switch 94 is switched to the activated state by being pressed by the driver, it is determined that there is a request to activate the driving force source PG.

When the activation request determination unit 104a determines that the activation request for the traveling driving force source PG has been received, the abnormality determining unit 104b uses the electric motor MG and the clutch K0 before the activation request for the traveling driving force source PG. It is determined whether or not a predetermined abnormality that prevents the engine 12 from being started has been detected. For example, whether or not a predetermined abnormality has been detected is determined based on whether or not it is stored that a predetermined abnormality has been detected by the abnormality detection unit 110, which will be described later. The predetermined abnormality is an abnormality in which the engine 12 cannot be cranked and started using the electric motor MG and the clutch K0. When the rotation speed sensor 86 is a resolver and the rotation angle learning of the resolver is not completed, (c) when communication abnormality (communication interruption) occurs between the engine control unit 102a and the clutch control unit 106 and so on. Rotational angle learning of the resolver is learning for correcting the difference between the rotational position of the electric motor MG detected by the resolver and the actual rotational position of the electric motor MG to be within a predetermined allowable range.

(a) If the system main relay 62 is faulty (for example, if the electrical resistance is high when the system main relay 62 is closed), the connection between the main battery 60 and the inverter 52 is not normal. Therefore, it is not preferable to crank the engine 12 using the electric motor MG and the clutch K0. (b) When the rotation angle learning of the resolver is not completed, for example, when the electric motor MG is driven and controlled by rectangular wave driving, an unintended driving force is output from the electric motor MG due to a phase shift. There is a risk that it will be Therefore, drive control of the electric motor MG by rectangular wave driving is prohibited, and there is a possibility that the cranking torque Tcr cannot be output from the electric motor MG when the rectangular wave driving is prohibited. (c) When a communication abnormality (communication disruption) occurs between the engine control unit 102a and the clutch control unit 106, the engine control unit 102a and the clutch control unit 106 are interlocked with the cranking of the engine 12 by the clutch K0 and the electric motor MG. Fuel supply and ignition to the engine 12 by the control unit 102a cannot be performed.

It is determined by the activation request determination unit 104a that a request for activation of the driving force source PG for traveling has been received, and it is determined by the abnormality determination unit 104b that a predetermined abnormality has been detected prior to the activation request for the driving force source PG for traveling. In this case, the activation method determination unit 104c determines to select an activation method that makes it possible to run in the engine running mode regardless of the state of the vehicle 10 . For example, immediately after receiving a request to activate the driving force source PG, both the vehicle speed V and the accelerator opening θacc are zero values, and the driving force source switching map is in the region of the BEV driving mode. However, the vehicle is in a state in which it is possible to run in the engine running mode. Then, the starting method determination unit 104c determines to perform start control of the engine 12 by cranking the engine 12 using the starter motor 70 (hereinafter referred to as "engine start control").

When the starting method determination unit 104c determines to execute engine start control using the starter motor 70, the engine control unit 102a and the clutch control unit 106 of the hybrid control unit 102 execute engine start control. Specifically, the engine control unit 102a causes the starter motor 70 to crank the engine 12 via the flywheel 12a, and starts fuel supply to the engine 12, ignition, and the like. The clutch control unit 106 switches the clutch K0 from the disengaged state to the engaged state via the half-engaged state after the engine 12 is completely fired (starts to operate) and becomes capable of self-sustaining operation. As a result, the driving force for running output from the engine 12 can be transmitted to the drive wheels 14 via the clutch K0. Hybrid control unit 102 causes vehicle 10 to run in the engine running mode after the engine start control is completed.

The activation request determining unit 104a determines that the activation request for the running driving force source PG has been received, and the abnormality determining unit 104b determines that the predetermined abnormality has not been detected before the activation request for the running driving force source PG. In this case, the activation method determination unit 104 c determines the activation method according to the state of the vehicle 10 . For example, if the vehicle speed V and the accelerator opening θacc are both zero values immediately after receiving a request to activate the driving force source PG, and the driving force source switching map is in the region of the BEV driving mode. , the engine start control is not executed, and the vehicle can be driven in the BEV driving mode. Hybrid control unit 102 causes vehicle 10 to run in any of the BEV running mode, the engine running mode, or the HEV running mode according to the state of vehicle 10 after the start of running. The hybrid control unit 102 and the clutch control unit 106 use the electric motor MG and the clutch K0 as necessary to crank the engine 12 and execute engine start control. Specifically, in accordance with the switching of the clutch K0 from the released state to the engaged state by the clutch control unit 106, the electric motor control unit 102b causes the electric motor MG to output the cranking torque Tcr until the cranking is completed. Control. In addition, the engine control unit 102a controls fuel supply to the engine 12, ignition, and the like in conjunction with cranking of the engine 12 by the clutch K0 and the electric motor MG.

Abnormality detection unit 110 detects whether vehicle 10 has a predetermined abnormality that prevents engine 12 from being started using electric motor MG and clutch K0. Further, when detecting a predetermined abnormality, the abnormality detection unit 110 stores that the predetermined abnormality has been detected. For example, the abnormality detection unit 110 turns off the abnormality detection flag when a predetermined abnormality is not detected, and turns on the abnormality detection flag when a predetermined abnormality is detected.

FIG. 2 is an example of a flow chart for explaining the control operation of the electronic control unit 100 shown in FIG. The flowchart of FIG. 2 is repeatedly executed in a state in which the traveling driving force source PG is stopped.

First, in step S10 corresponding to the function of the activation request determination unit 104a (hereinafter, the step is omitted), is there a request for activation of the driving force source PG for traveling by the driver pressing the vehicle power switch 94? No is determined. If the determination in S10 is affirmative, in S20 corresponding to the function of the abnormality determination section 104b, the engine 12 is started using the electric motor MG and the clutch K0 before the activation request for the driving force source PG for traveling in S10. It is determined whether or not a predetermined abnormality that cannot be performed has been detected. For example, it is determined whether or not the abnormality detection flag is on. If the determination in S10 is negative, the process ends.

If the determination in S20 is affirmative, engine start control using the starter motor 70 is executed in S30 corresponding to the functions of the start control unit 104 and the clutch control unit 106, and S40 corresponding to the function of the hybrid control unit 102 is executed. , the vehicle 10 is driven in the engine driving mode.

If the determination in S20 is negative, in S50 corresponding to the function of the hybrid control unit 102, the vehicle 10 is caused to run in the BEV running mode, the engine running mode, or the HEV running mode depending on the state of the vehicle 10. After execution of S50, in S60 corresponding to the function of the abnormality detection unit 110, it is detected whether or not a predetermined abnormality that prevents the engine 12 from being started has occurred in the vehicle 10 using the electric motor MG and the clutch K0. .

When the detection in S60 is affirmative, in S70 corresponding to the function of the abnormality detection unit 110, the abnormality detection flag is turned on. After execution of S40, if the detection of S60 is negative, or after execution of S70, in S80 corresponding to the function of hybrid control unit 102, driving force source PG for traveling is stopped. And it ends.

According to this embodiment, when a request to start the driving force source PG for traveling is received, a predetermined abnormality that prevents the engine 12 from being started using the electric motor MG and the clutch K0 is detected before the request for starting. In this case, the engine 12 is started using the starter motor 70 . In this way, when a predetermined abnormality that prevents the engine 12 from being started using the electric motor MG and the clutch K0 is detected before the start request is issued, the engine 12 is started using the starter motor 70. . The vehicle 10 is caused to travel by the driving force for traveling output from the started engine 12, that is, the vehicle 10 is caused to travel in the engine traveling mode, so that the main battery 60 that supplies power to the electric motor MG has a travelable distance. Since it is not limited to the amount of charge that is actually stored, it is possible to suppress a reduction in the travelable distance.

According to this embodiment, (a) when a predetermined abnormality is detected, the detection of the predetermined abnormality is stored by turning on the abnormality detection flag, and (b) the driving force for running is stored. When a request to start the engine PG is received and the abnormality detection flag stores that a predetermined abnormality has been detected, the starter motor 70 is used to start the engine 12 . For example, in some cases, the time required to detect a predetermined abnormality is longer than the time required for start-up control that is executed in response to a request to start the running driving force source PG. Even in such a case, since the detection of the predetermined abnormality is stored in advance in the abnormality detection flag, the detection of the predetermined abnormality is not stored in advance in the abnormality detection flag. Therefore, when a request to start the traveling driving force source PG is received, the starter motor 70 can be used to quickly execute the start control of the engine 12 . This suppresses deterioration of drivability.

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.

In the above-described embodiment, the engine 12 is started using the starter motor 70 when the abnormality detection flag stores that a predetermined abnormality has been detected when a request to start the traveling driving force source PG is received. However, the present invention is not limited to this aspect. For example, the electronic control unit 100 repeatedly detects whether or not a predetermined abnormality has occurred for each predetermined period of time, and after detecting that the predetermined abnormality has occurred, the electronic control unit 100 detects the occurrence of the driving force source for running. In this mode, the engine 12 is started using the starter motor 70 when a request to start the PG is received (that is, when a predetermined abnormality is detected prior to the request to start the drive power source PG). can be

In the above-described embodiment, when a predetermined abnormality is detected, the detection of the predetermined abnormality is stored by turning on the abnormality detection flag, but the present invention is not limited to this embodiment. Any mode may be used as long as it stores that a predetermined abnormality has been detected.

Although the torque converter 24 is used as the hydrodynamic transmission device in the above embodiment, the present invention is not limited to this aspect. For example, instead of the torque converter 24, another hydrodynamic transmission such as a fluid coupling that does not amplify torque may be used as the hydrodynamic transmission. Also, the hydrodynamic transmission device does not necessarily have to be provided, and may be replaced with, for example, a starting clutch.

Although the main battery 60 and the system main relay 62 are directly connected in the above embodiment, the present invention is not limited to this aspect. For example, a mode in which a boost converter is provided between main battery 60 and system main relay 62 may be employed. In this mode, the voltage of main battery 60 is boosted by the boost converter, and this boosted voltage is output to inverter 52 via system main relay 62 and power line 64 .

It should be noted that what has been described above is merely an embodiment of the present invention, and the present invention can be implemented in a mode with various modifications and improvements based on the knowledge of those skilled in the art without departing from the scope of the invention.

10: Hybrid vehicle 12: Engine (internal combustion engine)
70: Starter motor 100: Electronic control device (control device)
K0: Clutch (engagement device)
MG: electric motor PG: driving force source for traveling

Claims (1)

A control device for a hybrid vehicle, comprising: an internal combustion engine and an electric motor as driving force sources for running; an engagement device for connecting and disconnecting power transmission between the internal combustion engine and the electric motor; and a starter motor for starting the internal combustion engine and
When a request to start the driving force source for running is received, and a predetermined abnormality that prevents the internal combustion engine from being started using the electric motor and the engagement device is detected before the start request is received. A control device for a hybrid vehicle, wherein the starter motor is used to start the internal combustion engine.

Images