JP5973710B2 - Control device for hybrid vehicle - Google Patents

Description

  The present invention relates to a control apparatus for a hybrid vehicle including a starter motor that starts an engine.

  2. Description of the Related Art Conventionally, a hybrid vehicle control device is known that allows a drive motor to function as a starter motor when starting an engine during traveling in an electric vehicle travel mode using a drive motor as a travel drive source (see, for example, Patent Document 1). . In this case, the travelable region in the electric vehicle travel mode is set to a region where the required driving force of the driver is within a range obtained by subtracting the engine starting torque from the maximum output torque of the drive motor.

JP 2003-200758 JP

  However, in the conventional hybrid vehicle control device, since the drive motor functions as a starter motor at the time of engine startup while traveling, an engine start torque for starting the engine is secured as an extra power in the output torque of the drive motor. There is a need. Therefore, there is a problem that the drive motor torque during traveling in the electric vehicle traveling mode is limited, and the region in which the vehicle can travel in the electric vehicle mode is limited.

  The present invention has been made paying attention to the above problems, and an object of the present invention is to provide a control device for a hybrid vehicle capable of expanding a travelable region in an electric vehicle travel mode using a drive motor as a travel drive source. And

In order to achieve the above object, the hybrid vehicle control device of the present invention includes an engine, a starter motor, a drive motor, a restart mode switching means, and an EV region control means.
The starter motor starts the engine.
The drive motor can transmit motor torque to the engine and drive wheels.
The restart mode switching means is a starter motor restart mode in which an engine is started using the starter motor and an engine is started using the drive motor while an electric vehicle traveling mode using the drive motor as a drive source is selected. Switch between normal motor restart mode.
In the starter motor restart mode, the EV area control means is capable of starting the engine using the starter motor, and has a vehicle speed range between a lower limit threshold set for the low vehicle speed range and an upper limit threshold set for the high vehicle speed range. Sometimes , the travelable area in the electric vehicle travel mode is expanded as compared with the normal motor restart mode. Further, the upper limit threshold value is set to an upper limit value that suppresses the cranking rotational speed to a rotational speed that can be realized by the starter motor.

In the hybrid vehicle control device of the present invention, the startable motor restart mode in which the engine is started using the starter motor during the electric vehicle travel mode, the travelable region in the electric vehicle travel mode uses the drive motor. Thus, the vehicle is expanded more than the travelable region in the electric vehicle travel mode in the normal motor restart mode in which the engine is started.
That is, when the engine is started using the starter motor during traveling, the drive motor does not need to function as a starter motor. Therefore, it is not necessary to leave a surplus torque for engine start (engine start torque), which is secured when the drive motor functions as a starter motor, in the drive motor. As a result, the maximum output torque of the drive motor can be used as the driving torque.
As a result, it is possible to expand the travelable region in the electric vehicle travel mode using the drive motor as the travel drive source.

1 is an overall system diagram illustrating an FF hybrid vehicle to which a control device according to a first embodiment is applied. It is explanatory drawing which shows the transition conditions between EV mode and HEV mode. It is a flowchart which shows the flow of the EV area control process performed with the integrated controller of FF hybrid vehicle to which the control apparatus of Example 1 was applied. FIG. 5 is a mode characteristic diagram showing an EV-HEV selection map (EV mode travel region enlargement map) when the starter motor is used for engine start. It is a mode characteristic diagram showing an EV-HEV selection map (EV mode travel region normal map) when the drive motor is used for engine start. It is a flowchart which shows the flow of the restart mode switching process performed with the integrated controller of FF hybrid vehicle to which the control apparatus of Example 1 was applied. It is explanatory drawing which shows the transition conditions between starter motor restart mode and normal motor restart mode. In the FF hybrid vehicle to which the control device of the first embodiment is applied, the engine speed, the engine fuel injection state, the starter motor standby determination, the driver requested driving force, and the EV → HEV switching line when the engine can be started by the starter motor It is a time chart which shows each characteristic of.

  EMBODIMENT OF THE INVENTION Hereinafter, the form for implementing the control apparatus of the hybrid vehicle of this invention is demonstrated based on Example 1 shown in drawing.

First, the configuration will be described.
The configuration of the control device of the FF hybrid vehicle (an example of a hybrid vehicle) according to the first embodiment will be described by dividing it into an “overall system configuration”, an “EV region control configuration”, and a “restart mode switching configuration”.

[Overall system configuration]
FIG. 1 is an overall system diagram illustrating an FF hybrid vehicle to which the control device of the first embodiment is applied. FIG. 2 is an explanatory diagram showing transition conditions between the EV mode and the HEV mode. Hereinafter, the overall system configuration of the FF hybrid vehicle will be described with reference to FIG.

  As shown in FIG. 1, the FF hybrid vehicle S includes an engine 1, a first clutch 2, a motor / generator 3 (drive motor), a second clutch 4, a belt type continuously variable transmission 5, a starter motor. 6, first low voltage battery 7, second low voltage battery 8, circuit interruption relay 9, inrush current prevention relay 10, DC / DC converter 11, high voltage battery 12, inverter 13, 1 and 2nd electric load 14,15. In addition, 16 and 16 are front wheels (drive wheels), and 17 and 17 are rear wheels.

  The engine 1 is a gasoline engine or a diesel engine, and engine start control, engine stop control, throttle valve opening control, fuel cut control, and the like are performed based on an engine control command from the engine controller 20.

  The first clutch 2 is a clutch interposed between the engine 1 and the motor / generator 3. Engagement to release is controlled by a first clutch hydraulic pressure (CL1 hydraulic pressure) generated by a hydraulic unit (not shown) based on a control command from the CVT controller 21.

  The motor / generator 3 is a synchronous motor / generator in which a permanent magnet is embedded in a rotor and a stator coil is wound around a stator. Based on a control command from the motor controller 22, it is driven by applying a three-phase alternating current generated by the inverter 13. The motor / generator 3 operates as an electric motor that rotates by receiving power supplied from the high-voltage battery 12 via the inverter 13 (power running). Further, when the rotor of the motor / generator 3 receives rotational energy from the engine 1 or the left and right front wheels 16, 16, it functions as a generator that generates electromotive force at both ends of the stator coil, and a high voltage battery via the inverter 13. Charge 12 (regeneration).

  The second clutch 4 is a clutch interposed between the motor / generator 3 and the left and right front wheels 16, 16 between the motor shaft and the transmission input shaft. As with the first clutch 2, the second clutch 4 is controlled for engagement / slip engagement / release by a second clutch hydraulic pressure (CL2 hydraulic pressure) generated by a hydraulic unit (not shown) based on a control command from the CVT controller 21. Is done.

  The belt-type continuously variable transmission 5 is disposed at a downstream position of the second clutch 4, determines a target input rotational speed according to the vehicle speed VSP and the accelerator opening APO, and automatically changes the stepless speed ratio. The belt-type continuously variable transmission 5 is controlled by a primary hydraulic pressure and a secondary hydraulic pressure generated by a hydraulic unit (not shown) based on a control command from the CVT controller 21 to control a gear ratio that is a belt winding diameter ratio between two pulleys. Is done. A differential output (not shown) is connected to the transmission output shaft of the belt-type continuously variable transmission 5, and left and right front wheels 16, 16 are provided from the differential via left and right drive shafts, respectively.

  The starter motor 6 is a dedicated motor that starts the engine 1 and is driven by receiving power supply from the first low-voltage battery 7 when the inrush current prevention relay 10 is turned on based on a control command from the motor controller 22. This is a direct current motor. Here, the starter motor 6 is a jump-in starter motor that cranks by causing a pinion gear provided in the starter motor 6 to jump into a ring gear provided in the crankshaft of the engine 1.

  The first low-voltage battery 7 is charged by turning on the circuit breaker relay 9 and converting the DC high voltage from the high-voltage battery 12 into a DC low voltage by the DC / DC converter 11. The second low voltage battery 8 is always charged by converting the DC high voltage from the high voltage battery 12 into a DC low voltage by the DC / DC converter 11. Furthermore, by turning on the circuit interruption relay 9, it is possible to supply power from the second low voltage battery 8 to the starter motor 6. The first low voltage battery 8 is connected to the first and second electrical loads 14 and 15, but the first low voltage battery 7 is also connected to the first and second electric loads by turning on the circuit breaking relay 9. Electric power can be supplied to the electrical loads 14 and 15. Here, the first and second electrical loads 14 and 15 are, for example, PCT heaters, air conditioner systems, room lights, and other electrical components mounted on the vehicle.

  The inverter 13 converts the direct current from the high-voltage battery 12 into a three-phase alternating current and drives the motor / generator 3 during power running based on a control command from the motor controller 22. Further, during regeneration, the three-phase alternating current from the motor / generator 3 is converted into direct current, and the high voltage battery 12 is charged.

  As shown in FIG. 2, the FF hybrid vehicle S has an electric vehicle travel mode (hereinafter referred to as “EV mode”) and a hybrid vehicle travel mode (hereinafter referred to as “HEV mode”) as travel modes depending on driving modes. And).

  The “EV mode” is a mode in which the first clutch 2 is disengaged, the engine 1 is stopped and the motor / generator 3 is used as the driving source, and the motor driving mode and the regenerative driving mode are provided. Drive in the mode. This “EV mode” is selected when the required driving force of the driver is low and there is no system requirement.

  The “HEV mode” is a mode in which the first clutch 2 is engaged and the engine 1 and the motor / generator 3 are used as drive sources, and includes a motor assist travel mode, a power generation travel mode, and an engine travel mode. Drive in any mode. This “HEV mode” is selected when the required driving force of the driver is high or when there is a system request such as a shortage of the battery SOC of the high voltage battery 12.

That is, in order to transition from EV mode to HEV mode, when the required driving force of the driver exceeds the preset EV⇒HEV switching line (engine start line), or an engine start request is generated due to a system request Is the case.
Here, the system required starting conditions are listed: road surface gradient, air conditioner condition, engine hood, engine water temperature, atmospheric pressure, brake negative pressure, transmission hydraulic oil temperature, first clutch facing estimated temperature, high voltage battery SOC, high voltage There are battery output possible voltage, motor possible torque, power consumption other than driving force, front defogger switch, rear defogger switch, oxygen concentration of three-way catalyst, etc.

  On the other hand, to change from HEV mode to EV mode, when the driver's required driving force falls below the preset HEV⇒EV switching line (engine stop line) and there is no engine start request due to system request It is.

  As shown in FIG. 1, the control system of the FF hybrid vehicle S includes an engine controller 20, a CVT controller 21, a motor controller 22, and an integrated controller 23. The controllers 20, 21, 22 and the integrated controller 23 are connected via a CAN communication line 24 that can exchange information with each other.

  The engine controller 20 includes engine speed information from the engine speed sensor 27, crank angle information from the crank angle sensor 28, engine state information from the reverse rotation detection sensor 29, and target engine torque from the integrated controller 23. Enter the command and other necessary information. Then, a command for controlling the engine operating point (Ne, Te) is output to the throttle valve actuator or the like of the engine 1.

  The CVT controller 21 inputs information from an accelerator opening sensor 25, a vehicle speed sensor 26, and other sensors 30 and the like. When traveling with the D range selected, a search command for a target input speed determined by the accelerator opening APO and the vehicle speed VSP is retrieved from the shift map, and a control command for obtaining the searched target input speed (speed ratio) is sent to the belt. Is output to a hydraulic unit (not shown) provided in the continuously variable transmission 5. In addition to this gear ratio control, clutch hydraulic pressure control of the first clutch 2 and the second clutch 4 is performed.

  The motor controller 22 inputs the rotor rotational position information, the target MG torque command and the target MG rotational speed command from the integrated controller 23, and other necessary information. Then, a command for controlling the motor operating point (Nm, Tm) of the motor / generator 3 is output to the inverter 13. The motor controller 22 also performs drive control of the starter motor 6 that issues a starter activation signal (ON) to the circuit interruption relay 9 and the inrush current prevention relay 10 when the engine is started.

  The integrated controller 23 manages the energy consumption of the entire vehicle and has a function for running the vehicle with the highest efficiency. In the integrated controller 23, necessary information from the accelerator opening sensor 25, the vehicle speed sensor 26, the engine speed sensor 27, the crank angle sensor 28, the reverse rotation detection sensor 29, and other sensors 30 is directly received, or CAN communication is performed. Input via line 24.

[EV area control configuration]
FIG. 3 is a flowchart showing a flow of EV region control processing executed by the integrated controller of the FF hybrid vehicle to which the control device of the first embodiment is applied (EV region control means). FIG. 4 is a mode characteristic diagram showing an EV-HEV selection map (EV mode travel region enlarged map) when the starter motor is used for engine start. FIG. 5 is a mode characteristic diagram showing an EV-HEV selection map (EV mode travel region normal map) when the drive motor is used for engine start.
Hereinafter, each step of FIG. 3 representing the EV area control configuration will be described.

  In step S1, it is determined whether or not traveling by selecting “EV mode” is permitted. If YES (EV travel permission), the process proceeds to step S2, and if NO (EV travel is not permitted), step S1 is repeated.

In step S2, following the determination that EV travel permission is permitted in step S1, it is determined whether or not the engine can be started by the starter motor 6 during traveling, that is, the engine starting during traveling is started using the starter motor 6. It is determined whether it is a starter motor restart mode to be performed or a normal motor restart mode in which the engine during running is started using the motor / generator 3. If YES (starter motor can be used = starter motor restart mode), the process proceeds to step S3. If NO (starter motor cannot be used = normal motor restart mode), the process proceeds to step S4.
Here, whether or not the starter motor 6 can start the engine is determined based on a restart mode switching process described later.

  In Step S3, following the determination that the starter motor can be used in Step S2, that is, the starter motor restart mode, EV-HEV selection used when calculating the target travel mode (EV mode, HEV mode) The map is set to use the EV mode travel area enlarged map shown in FIG. 4, and the process proceeds to the end.

  In step S4, following the determination that the starter motor cannot be used in step S2, that is, the normal motor restart mode, the EV mode travel region normal map shown in FIG. 5 is used as the EV-HEV selection map. Set to, and go to the end.

  Here, the “EV-HEV selection map” is an area in which the vehicle can travel in the EV mode according to the driver's required driving force (accelerator opening APO) and the vehicle speed VSP (an area indicated as “EV” in FIGS. 4 and 5). , Hereinafter referred to as an EV region) and a map in which a travelable region in HEV mode (a region indicated as “HEV” in FIGS. 4 and 5, hereinafter referred to as a HEV region) is set. The EV area and the HEV area are divided by an EV → HEV switching line (engine start line) and an HEV → EV switching line (engine stop line). In the EV-HEV selection map, if the operating point (APO, VSP) existing in the EV region exceeds the EV⇒HEV switching line, an engine start request is generated and the target travel mode is switched to the “HEV mode”. . Further, when the operating point (APO, VSP) existing in the HEV region falls below the HEV → EV switching line, an engine stop request is generated and the target travel mode is switched to “EV mode”.

  The “EV mode travel area enlarged map” is a map obtained by enlarging the EV area as compared with the EV area in the “EV mode travel area normal map”.

  In other words, in the “EV mode travel region normal map”, the EV → HEV switching line that divides the EV region and the HEV region is the maximum output torque of the motor / generator 3 that is determined according to the vehicle speed VSP (indicated by a one-dot chain line in FIG. 5). From this, a value obtained by subtracting the torque required for starting the engine 1 (engine starting torque) is used.

On the other hand, in the “EV mode travel area expansion map”, in the vehicle speed range where the engine can be started using the starter motor 6, the EV / HEV switching line that divides the EV region and the HEV region is determined according to the vehicle speed VSP. A value obtained by subtracting torque (starting assist torque) corresponding to the rotation increase assist at the start of the engine 1 from the maximum output torque of the generator 3 (indicated by a one-dot chain line in FIG. 4).
Here, the “rotation increase assist torque” is a margin that is left in the motor / generator 3 assuming that the engine speed cannot be sufficiently increased by the cranking torque and the initial explosion torque by the starter motor 6. Torque.
The “vehicle speed range in which the engine can be started using the starter motor 6” is a vehicle speed range between the lower threshold value VSP1 and the upper threshold value VSP2 shown in FIG. The lower limit threshold value VSP1 is a vehicle speed threshold value that prevents the occupant from feeling the jumping sound and driving sound of the starter motor 6 due to background noise (= environmental noise), and does not make the occupant feel uncomfortable. When the vehicle speed VSP is lowered, background noise is reduced and the starter motor 6 cannot start the engine. The upper threshold value VSP2 is a vehicle speed threshold value at which the engine speed necessary for cranking the engine 1 can be output by the starter motor 6. When the vehicle speed VSP increases, the engine speed required for cranking increases, and the starter motor 6 cannot start the engine.
In this “EV mode travel area expansion map”, in the vehicle speed range other than the vehicle speed range where the starter motor 6 can be used to start the engine, the EV⇒HEV switching line is changed from the maximum output torque of the motor / generator 3 to the engine. The value obtained by subtracting the starting torque.

[Restart mode switching configuration]
FIG. 6 is a flowchart showing a flow of restart mode switching processing executed by the integrated controller of the FF hybrid vehicle to which the control device of the first embodiment is applied (restart mode switching means). FIG. 7 is an explanatory diagram showing transition conditions between the starter motor restart mode and the normal motor restart mode.
Hereinafter, each step of FIG. 6 representing the restart mode switching configuration will be described.

In step S10, it is determined whether the engine 1 has stopped. If YES (engine stop), the process proceeds to step S11. If NO (engine drive), the process proceeds to step S18.
Here, the determination of the engine stop is made based on the engine speed information from the engine speed sensor 27 or the engine state information from the reverse rotation detection sensor 29. When the engine speed is equal to or lower than the predetermined speed or when the engine speed is in a preset stop state, it is determined that the engine is stopped.

In step S11, following the determination that the engine is stopped in step S10, it is determined whether or not the first and second low-voltage batteries 7 and 8 have deteriorated. If YES (no deterioration), the process proceeds to step S12. If NO (deterioration), the process proceeds to step S18.
If the first and second low-voltage batteries 7 and 8 are deteriorated, the voltage drop of the low-voltage system circuit becomes less than a predetermined threshold value, and the system may stop instantaneously. Restrict.

In step S12, following the determination in step S11 that there is no battery deterioration, whether or not the first and second low voltage batteries 7 and 8 both have sufficient battery SOC, that is, the battery charge state is sufficient. Judge whether there is. If YES (SOC present), the process proceeds to step S13. If NO (SOC shortage), the process proceeds to step S18.
Here, the battery SOC state (battery charge state) is determined based on the output voltage of the first and second low voltage batteries 7 and 8 and the charge state of the DC / DC converter 11.
When the first and second low-voltage batteries 7 and 8 are discharged due to being left for a long period of time or the like, the starter motor 6 cannot be sufficiently supplied with power, and it takes time to start the engine. The starter motor 6 is restricted from being used because there is a risk that the system will stop or the system may stop instantaneously.

In step S13, following the determination that the battery SOC is present in step S12, the power consumption in the first and second electrical loads 14 and 15 connected to the first and second low voltage batteries 7 and 8 is less than a predetermined threshold. Determine if it is small. If YES (low power consumption), the process proceeds to step S14. If NO (high power consumption), the process proceeds to step S18.
When the power consumption at the first and second electrical loads 14 and 15 is high, such as when the PCT heater is being driven, the margin for the threshold at which the system stops instantaneously becomes small, and the voltage drop of the low voltage circuit is below this threshold. Therefore, the use of the starter motor 6 is restricted.

In step S14, following the determination that power consumption is low in step S13, it is determined whether or not the temperature of the starter motor 6 is lower than a predetermined threshold, that is, whether or not the starter motor 6 is overheated. If YES (starter non-overheating), the process proceeds to step S15. If NO (starter overheating), the process proceeds to step S18.
Since the motor temperature rises immediately after the start of the engine by the starter motor 6, the use of the starter motor 6 is restricted in consideration of the inability to start next time and the influence on durability.

In step S15, following the determination that the starter is not overheated in step S14, it is determined whether or not the number of uses of the starter motor 6 has exceeded a predetermined number. If YES (less than a predetermined number), the process proceeds to step S16, and if NO (more than a predetermined number), the process proceeds to step S18.
The use of the starter motor 6 is limited because there are components that affect the durability depending on the number of times the engine is started by the starter motor 6.

In step S16, following the determination that the number of times of use in step S15 is less than a predetermined number, it is determined whether there is no drive request from the driver and engine start by the motor / generator 3 is impossible. If YES (no drive request and motor / generator start disabled), the process proceeds to step S17. If NO (no drive request required and motor / generator start enabled), the process proceeds to step S18.
Here, the driving request by the driver is determined based on the accelerator opening APO. If the accelerator is depressed (accelerator opening increases), it is determined that there is a drive request (acceleration request). Further, when the engine is started by the motor / generator 3, if the current driving force can be maintained, it is determined that the engine can be started by the motor / generator 3.
Note that starting the engine using the motor / generator 3 prevents the starter motor 6 from deteriorating and gives priority to the drivability and noise vibration performance, so that the use of the starter motor 6 is limited.

  In step S17, following the determination that there is no drive request in step S16 and that the motor / generator cannot be started, it is determined that the starter motor 6 can start the engine while traveling. That is, the engine restart mode is set to a starter motor restart mode in which the starter motor 6 is started using the starter motor 6. Then go to the end.

  In step S18, it is determined that the engine is driven in step S10, it is determined that there is battery deterioration in step S11, it is determined that battery SOC is insufficient in step S12, it is determined that power consumption is large in step S13, and in step S14. Following the determination that the starter is overheated, the determination that the number of times of use is greater than or equal to the predetermined number in step S15, and the determination that there is no drive request and that the motor / generator can be started in step S16. It is determined that the engine can be started. That is, the engine restart mode is set to the normal motor restart mode in which the engine during running is started using the motor / generator 3. Then go to the end.

  As shown in FIG. 7, in order to transition from the normal motor restart mode to the starter motor restart mode, the engine can be started by the starter motor 6 in which the target travel mode is the EV mode (engine rotation is stopped). Therefore, it is necessary to satisfy the conditions that all the restart conditions (steps S11 to S16) by the starter motor 6 are satisfied, that is, the restart prohibition condition is not satisfied.

  On the other hand, the transition from the starter motor restart mode to the normal motor restart mode is when the target travel mode is changed to the HEV mode after the starter motor restart mode. In other words, in the starter motor restart mode, if the running mode transitions from the EV mode to the HEV mode by starting the engine using the starter motor 6, the engine restart mode temporarily becomes the normal motor restart mode.

  Next, the EV mode expansion action of the hybrid vehicle control device of the first embodiment will be described.

[EV mode expansion effect]
FIG. 8 shows an FF hybrid vehicle to which the control device of the first embodiment is applied. When the engine can be started by the starter motor, the engine speed, the engine fuel injection state, the starter motor standby determination, the driver requested driving force, the EV => It is a time chart showing each characteristic of the HEV switching line.

  In the FF hybrid vehicle S to which the hybrid vehicle control device according to the first embodiment is applied, the travelable area in the EV mode in the starter motor restart mode is more than the travelable area in the EV mode in the normal motor restart mode. Is also expanding.

That is, when the FF hybrid vehicle S of the first embodiment is traveling in the vehicle speed range (VSP1 <vehicle speed <VSP2) where the engine can be started using the starter motor 6 during the HEV mode, at time t1 shown in FIG. When the opening APO decreases and the driver's required driving force decreases, the fuel supply to the engine 1 is turned off.
At this time, even if the fuel supply is stopped, the engine 1 rotates due to inertia and the engine speed does not fluctuate. Therefore, in the flowchart shown in FIG. 6, the process proceeds from step S10 to step S18, and the normal motor restart mode is set. That is, even if the fuel supply to the engine 1 is turned OFF due to a decrease in the driving force required by the driver, the engine cannot be started using the starter motor 6 and the standby determination of the starter motor 6 remains OFF.
Thus, the “EV mode travel region normal map” is used as the EV-HEV selection map, and the EV → HEV switching line is set to a value obtained by subtracting the engine starting torque from the motor / generator maximum output torque. As a result, the output possible torque of the motor / generator 3 is limited by the engine starting torque, and the EV⇒HEV switching line becomes a low value with respect to the required driving force.

At time t2, if the driver's required driving force falls below the EV → HEV switching line and falls below the HEV → EV switching line (not shown here), the target driving mode is switched to the EV mode.
At this time, since the engine 1 continues to rotate due to inertia, the engine speed does not decrease. In the flowchart shown in FIG. 6, the process proceeds from step S10 to step S18, and the normal motor restart mode is continuously set.

  At time t3, the engine speed starts to decrease. Even in this case, the engine speed is high and it is not determined that the engine is stopped. For this reason, in the flowchart shown in FIG. 6, the process proceeds from step S10 to step S18, and the normal motor restart mode is continuously set.

  When the engine speed reaches the number of times that it can be determined that the engine is stopped at time t4, that is, becomes zero, the process proceeds from step S10 to step S11 in the flowchart shown in FIG. The state of the first and second low-voltage batteries 7 and 8, SOC, power consumption by the first and second electrical loads 14 and 15, the temperature and the number of times of use of the starter motor 6, the presence or absence of a drive request, the motor / generator 3 Detects whether or not starting is possible. As a result, if the restart prohibition condition by the starter motor 6 is not satisfied, in the flowchart shown in FIG. 6, the process proceeds from step S11 → step S12 → step S13 → step S14 → step S15 → step S16 → step S17. It is determined that the engine can be started while the motor 6 is traveling. That is, the starter motor restart mode is set, and the starter motor standby determination is turned ON.

  Thereby, in the flowchart shown in FIG. 3, the process proceeds from step S1 to step S2 to step S3, and the EV-HEV selection map uses the “EV mode travel area expansion map”. At this time, since the FF hybrid vehicle S is running in the vehicle speed range (VSP1 <vehicle speed <VSP2) where the engine can be started using the starter motor 6, the EV⇒HEV switching line starts from the motor / generator maximum output torque. It is set to a value obtained by subtracting the assist torque. In other words, the output possible torque of the motor / generator 3 is no longer limited by the engine starting torque, and the EV⇒HEV switching line is higher than the required driving force than when the normal motor restart mode is set. It becomes.

  For this reason, even if the driver's required driving force increases at time t5, this required driving force does not exceed the EV⇒HEV switching line, and the vehicle can travel in the EV mode. As a result, the traveling state in the EV mode can be maintained, and the travelable area in the EV mode can be expanded.

  On the other hand, the extension of the travelable area in the EV mode is set in the vehicle speed range (VSP1 to VSP2) where the engine can be started using the starter motor 6 in the “EV mode travel area expansion map”. That is, expansion of the travelable region in the EV mode can be performed after appropriately determining that the engine can be started during travel using the starter motor 6. Therefore, even if the engine start torque is not left and the output torque of the motor / generator 3 is used for traveling, the starter motor 6 can appropriately start the engine if there is an engine start request. For this reason, it can prevent that engine startability deteriorates.

In particular, in the case of the first embodiment, the lower limit threshold value VSP1 is set to a vehicle speed threshold value that prevents the occupant from feeling the jumping sound and driving sound of the starter motor 6 due to background noise (= environmental noise). . For this reason, the engine can be started by the starter motor 6 without giving the passenger a sense of incongruity, and deterioration of the engine startability can be prevented.
Further, the upper threshold value VSP2 is set to a vehicle speed threshold value at which the engine speed necessary for cranking the engine 1 can be output by the starter motor 6. For this reason, the vehicle speed VSP when the engine is started by the starter motor 6 is limited, the engine start by the starter motor 6 can be secured, and deterioration of the engine startability can be prevented.

  In the first embodiment, the EV → HEV switching line when the starter motor restart mode is set is set to a value obtained by subtracting the start assist torque from the motor / generator maximum output torque. For this reason, even if the cranking by the starter motor 6 and the initial explosion torque of the engine 1 are not sufficient to increase the engine, the motor / generator 3 increases the engine speed so that the engine starts smoothly. Deterioration of engine startability can be prevented.

  In the FF hybrid vehicle S of the first embodiment, the starter motor 6 can start the engine when the engine 1 is stopped. Therefore, the engine cannot be started by the starter motor 6 while the engine 1 cannot rotate due to inertia and the starter motor 6 can jump. Thereby, a smooth engine start by the starter motor 6 can be ensured, and an engine start delay can be prevented.

  Furthermore, in the FF hybrid vehicle S of the first embodiment, when the first and second low voltage batteries 7 and 8 are deteriorated, when the charge state of the first and second low voltage batteries 7 and 8 is low, the first , When the power consumption of the first and second electrical loads 14 and 15 connected to the second low-voltage batteries 7 and 8 is high, the engine start during running using the starter motor 6 is started. not allowed. As a result, when the engine is started by the starter motor 6, it is possible to prevent the output voltage from the first and second batteries 7 and 8 from being lowered and affecting the operation of the first and second electrical loads 14 and 15.

  Furthermore, in the FF hybrid vehicle S of the first embodiment, when the starter motor 6 is overheated, engine start during traveling using the starter motor 6 is not permitted. Thereby, it is possible to prevent the starter motor 6 from being overheated and affecting the engine starting performance and the durability of the starter motor 6 when the starter motor 6 is used.

  In the FF hybrid vehicle S of the first embodiment, even when the starter motor 6 is used more than a predetermined number of times, the engine start during running using the starter motor 6 is not permitted. Thereby, deterioration of the engine starting system when using the starter motor 6 can be prevented, and the engine starting performance when using the starter motor 6 can be prevented from being affected.

  Further, in the FF hybrid vehicle S of the first embodiment, when there is no drive request from the driver and the engine can be started by the motor / generator 3, the engine during running is started using the motor / generator 3. As a result, deterioration of the engine starting system when using the starter motor 6 can be prevented, and priority can be given to drivability and noise vibration performance.

Next, the effect will be described.
In the hybrid vehicle control apparatus of the first embodiment, the following effects can be obtained.

(1) Engine 1 and
A starter motor 6 for starting the engine 1;
A motor / generator 3 capable of transmitting motor torque to the engine 1 and the front wheels 16, 16;
A starter motor restart mode in which an engine is started using the starter motor 6 while the electric vehicle running mode using the motor / generator 3 as a drive source is selected; Restart mode switching means (FIG. 6) for switching between normal motor restart mode for starting the engine;
EV region control means (FIG. 3) that expands the travelable region in the electric vehicle travel mode in the starter motor restart mode than in the normal motor restart mode;
It was set as the structure provided with.
Thereby, it is possible to expand the travelable region in the electric vehicle travel mode using the motor / generator 3 as the travel drive source.

(2) When the EV area control means (FIG. 3) is in a vehicle speed area (VSP1 to VSP2) in which the engine can be started using the starter motor 6, the electric motor travel mode is determined as the normal motor. The configuration is larger than that in the restart mode.
Accordingly, it is possible to expand the EV mode travelable region after appropriately determining that the engine can be started during traveling using the starter motor, and it is possible to prevent deterioration of engine startability.

(3) The starter motor 6 is a dive starter motor,
The restart mode switching means (FIG. 6) is configured to set the starter motor restart mode when the engine is stopped.
Thereby, engine start using starter motor 6 can be performed smoothly, and generation of engine start delay can be prevented.

(4) a first low-voltage battery 7 for supplying power to the starter motor 6;
The restart mode switching means (FIG. 6) is connected to the first low voltage battery 7 when the first low voltage battery 7 is deteriorated or when the charge state of the first low voltage battery 7 is low. In the case where the power consumption by the first electrical load 14 is high, the normal motor restart mode is set.
As a result, it is possible to prevent the output voltage from the first low-voltage battery 7 from being lowered when starting the engine using the starter motor 6 and affecting the operation of the first electrical load 14.

(5) The restart mode switching means (FIG. 6) is configured to set the normal motor restart mode when the temperature of the starter motor 6 is equal to or higher than a predetermined threshold.
Thereby, it is possible to prevent the starter motor 6 from being overheated and affecting the engine start system using the starter motor 6 and the durability of the starter motor 6.

(6) The restart mode switching unit is configured to set the normal motor restart mode when the number of times the starter motor is used is equal to or greater than a predetermined threshold.
Thereby, it is possible to prevent the engine start performance by the starter motor 6 from being affected by the deterioration of the engine start system using the starter motor 6.

(7) The restart mode switching means is configured to set the normal motor restart mode when there is no driver acceleration request and the driving force can be maintained even when the engine is started by the drive motor. did.
As a result, deterioration of the engine starting system using the starter motor 6 can be prevented and priority can be given to drivability and noise vibration performance.

  Although the hybrid vehicle control device of the present invention has been described based on the first embodiment, the specific configuration is not limited to this embodiment, and the invention according to each claim of the claims is not limited thereto. Design changes and additions are allowed without departing from the gist.

In the first embodiment, the starter motor 6 is a jump-in starter motor, and the starter motor restart mode is set when it is determined that the engine 1 has stopped. However, the present invention is not limited thereto. For example, when the starter motor 6 is a rotation-synchronized starter motor, the engine 1 and the starter motor 6 are coupled, and the rotation speed of the engine 1 can be cranked by the starter motor 6. When the number reaches, the starter motor restart mode may be set.
Even in this case, the engine start using the starter motor 6 can be performed smoothly, and the engine start delay can be prevented.
The “rotation-synchronized starter motor” is a starter motor that couples the engine 1 and the starter motor 6 when the rotation of the engine 1 and the rotation of the starter motor 6 are synchronized. In this case, for example, the engine rotation state is determined based on crank angle information from the crank angle sensor 28.
The “number of revolutions that can be cranked” is the number of revolutions at which cranking torque can be output by the starter motor 6. When the engine speed is larger than the “cranking speed”, the starter motor 6 cannot output the cranking torque.

Further, for example, when the starter motor 6 is a constant mesh type starter motor, the starter motor restart mode is set when the rotational speed of the engine 1 becomes a crankable rotational speed by the starter motor 6. You may do it.
Even in this case, the engine start using the starter motor 6 can be performed smoothly, and the engine start delay can be prevented.
The “always meshing starter motor” is a starter motor in which the engine 1 and the starter motor 6 are always coupled.

Furthermore, in the first embodiment, as the EV area control means, when the EV mode travel area enlargement map is expanded in the EV mode travel area enlargement map, the EV⇒HEV switching line changes from the motor / generator maximum output torque to the start assist torque. An example is shown in which the value is set by subtracting. However, the EV → HEV switching line that divides the travelable region in the EV mode may be set to a value that provides the maximum motor / generator output torque.
Thereby, all the torque that can be output by the motor / generator 3 can be used as a travel drive source, and the travelable area in the EV mode can be further expanded.

  Further, in the first embodiment, as the restart mode switching means, the starter motor restart mode is set when all restart conditions by the starter motor 6 shown in the steps of FIG. 6 are satisfied. However, the restart condition by the starter motor 6 shown in each step of the flowchart shown in FIG. 6 can be arbitrarily selected. That is, the starter motor restart mode may be set even if all the steps in FIG. 6 are not necessarily established.

Furthermore, in the first embodiment, as an example of restart mode switching means, it is shown in step S11 in FIG. 6 whether or not the first and second low-voltage batteries 7 and 8 are all deteriorated. In S12, an example is shown in which it is determined whether or not the first and second low-voltage batteries 7 and 8 both have sufficient battery SOC. In step S13, the first and second electrical loads 14 and 15 An example is shown in which it is determined whether or not the power consumption is smaller than a predetermined threshold.
However, the degradation state of the first low-voltage battery 7 that mainly supplies power to the starter motor 6, the battery SOC, and the power consumption of the first electrical load 14 that is mainly supplied with power from the first low-voltage battery 7. Only for the above, a restart condition by the starter motor 6 may be used.

  In the first embodiment, an example in which the hybrid vehicle control device of the present invention is applied to the FF hybrid vehicle S with one motor and two clutches is shown. However, the hybrid vehicle control device of the present invention is also applicable to an FF or FR hybrid vehicle that does not include the first clutch 2, the second clutch 4, the belt type continuously variable transmission 5, or the like in the drive system. Can do. In short, the present invention can be applied to any control device for a hybrid vehicle including an engine starter motor and a drive motor that also serves as an engine starter motor.

1 Engine 2 First clutch 3 Motor / generator (drive motor)
4 Second clutch 5 Belt type continuously variable transmission 6 Starter motor 7 First low voltage battery 8 Second low voltage battery 9 Circuit breaker relay 10 Inrush current prevention relay 11 DC / DC converter 12 High voltage battery 13 Inverter 14 First electrical load 15 Second electrical load 16 Front wheel (drive wheel)
17 Rear wheel 20 Engine controller 21 CVT controller 22 Motor controller 23 Integrated controller 24 CAN communication line

Claims (9)

Engine,
A starter motor for starting the engine;
A drive motor capable of transmitting motor torque to the engine and drive wheels;
A starter motor restart mode for starting an engine during traveling using the starter motor while an electric vehicle traveling mode using the drive motor as a drive source is selected, and a normal engine starting during traveling using the drive motor Restart mode switching means for switching between the motor restart mode,
In the starter motor restart mode, when the starter motor can be started, the electric vehicle travels when the vehicle speed range is between a lower threshold value set at a low vehicle speed range and an upper threshold value set at a high vehicle speed range. EV area control means that expands the travelable area in the mode than in the normal motor restart mode,
Equipped with a,
The EV region control means sets the upper limit threshold value to an upper limit value that suppresses the cranking rotational speed to a rotational speed that can be realized by the starter motor . In the hybrid vehicle control device according to claim 1,
The control device for a hybrid vehicle, wherein the EV area control means sets the lower limit threshold value to a lower limit value that does not give a sense of incongruity when starting the engine using the starter motor due to background noise. In the hybrid vehicle control device according to claim 1 or 2,
The starter motor is a dive starter motor,
The restart mode switching means sets the starter motor restart mode when the engine is stopped. In the hybrid vehicle control device according to claim 1 or 2,
The starter motor is a rotation synchronous starter motor,
The restart mode switching means sets the starter motor restart mode when the engine and the starter motor are coupled and when the engine speed reaches a crankable speed. Control device for hybrid vehicle. In the hybrid vehicle control device according to claim 1 or 2,
The starter motor is a constant mesh starter motor,
The hybrid vehicle control device, wherein the restart mode switching means sets the starter motor restart mode when the engine speed reaches a crankable speed. In the control apparatus of the hybrid vehicle as described in any one of Claims 1-5,
A battery for supplying power to the starter motor;
When the battery is deteriorated, when the battery is in a low charge state, or when the power consumption by the electrical load connected to the battery is high, the restart mode switching means is the normal motor. A control apparatus for a hybrid vehicle, characterized in that a restart mode is set. In the control apparatus of the hybrid vehicle as described in any one of Claims 1-6,
The said restart mode switching means sets the said normal motor restart mode, when the temperature of the said starter motor is more than a predetermined threshold value. The hybrid vehicle control apparatus characterized by the above-mentioned. In the control apparatus of the hybrid vehicle as described in any one of Claims 1-7,
The said restart mode switching means sets the said normal motor restart mode, when the frequency | count of use of the said starter motor is more than a predetermined threshold value. The hybrid vehicle control apparatus characterized by the above-mentioned. In the control apparatus of the hybrid vehicle as described in any one of Claims 1-8,
The restart mode switching means sets the normal motor restart mode when there is no driver acceleration request and the driving force can be maintained even when the engine is started while the drive motor is running. Control device for hybrid vehicle.