JP5954859B2 - Control device for hybrid electric vehicle - Google Patents

Description

  The present invention relates to a control apparatus for stopping rotation of an engine at a crank angle suitable for starting when the engine is automatically stopped in a hybrid electric vehicle including an engine and a motor as drive sources.

In recent years, there has been a so-called idle stop / auto start (automatic stop / restart) control that improves fuel efficiency and exhaust gas performance by automatically stopping the engine during parking and waiting for a signal and automatically restarting at the time of departure. Has been done.
In such automatic stop / restart control, after the engine is automatically stopped, it is necessary to start the engine quickly so that the vehicle can be started quickly.

The startability of the engine changes depending on the stop position of the piston. If the piston is stopped at a position suitable for cranking, the engine can be started quickly.
Therefore, a technique has been developed in which the piston is stopped at an appropriate position suitable for cranking by a starter by adjusting the target generated current of the alternator when the engine is automatically stopped (see Patent Document 1).

  In recent years, hybrid electric vehicles equipped with an engine and a motor as drive sources have been developed to reduce fuel consumption and exhaust gas performance, and automatic stop / restart control of the engine is also applied to the hybrid electric vehicles. Has been.

JP 2004-17919 A

In the case of a hybrid electric vehicle, if the engine is automatically stopped in a state where the engine and the motor are connected, the mass load of the motor is applied in addition to the engine, and the load for stopping the rotation of the engine increases.
Therefore, when the technique of Patent Document 1 is applied to a hybrid electric vehicle, there is a problem that the load on the alternator for stopping the rotation of the engine is increased, and the durability and reliability of the alternator are reduced. Further, if the power generation amount of the alternator is increased, there arises a problem that the alternator is increased in size.

  The present invention has been made to solve such problems, and the object of the present invention is to reduce the durability and reliability of the alternator and increase the size in the automatic stop / restart control of the hybrid electric vehicle. An object of the present invention is to provide a control device for a hybrid electric vehicle that can stop the rotation of the engine at a crank angle suitable for starting and can quickly restart the engine.

  In order to achieve the above object, the hybrid electric vehicle control device according to claim 1 is a hybrid electric vehicle control device capable of selecting an engine and a motor as a drive source, and generates electric power using the driving force of the engine. And a clutch means provided between the engine and the motor for connecting and disconnecting the driving force of the engine transmitted from the engine to the drive wheels via the motor, and a predetermined engine When fuel supply stop control means for stopping fuel supply to the engine when the automatic stop condition is satisfied, and when the clutch means is in a connected state when the predetermined engine automatic stop condition is satisfied, The rotation of the engine at a predetermined stop crank angle suitable for starting the engine by the torque generated by the motor. Engine rotation stop control means for stopping rotation of the engine at a predetermined stop crank angle suitable for starting the engine from a load accompanying power generation of the alternator when the clutch means is in a disconnected state; It is characterized by having.

  According to a second aspect of the present invention, there is provided a hybrid electric vehicle control apparatus according to the first aspect, wherein the engine rotation stop control means is configured such that a charge amount of a battery supplying electric power to the motor is a predetermined upper limit charge amount. When it is above, the clutch means is disengaged, and the rotation of the engine is stopped at a predetermined stop crank angle suitable for starting the engine by a load accompanying power generation of the alternator.

  According to a third aspect of the present invention, there is provided the hybrid electric vehicle control apparatus according to the first or second aspect, further comprising a starter that is provided in the engine and performs cranking of the engine. If the charge amount of the battery that supplies power to the motor is equal to or greater than a first predetermined charge amount, the first stop crank angle suitable for cranking by the motor is set and the power is supplied to the motor. When the charge amount of the battery to be operated is less than the first predetermined charge amount, a second stop crank angle suitable for cranking by the starter is set.

  5. The hybrid electric vehicle control apparatus according to claim 4, wherein the engine rotation stop control means is a battery for supplying electric power to the motor when the clutch means is in a connected state. Is equal to or greater than a second predetermined charge amount, the engine torque is stopped at a predetermined stop crank angle suitable for starting the engine by the driving torque of the motor, and electric power is supplied to the motor. When the charge amount of the battery to be supplied is less than the second predetermined charge amount, the rotation of the engine is stopped at a predetermined stop crank angle suitable for starting the engine by the regenerative torque of the motor. It is a feature.

  According to the control apparatus for a hybrid electric vehicle of the present invention using the above means, in the hybrid electric vehicle in which the clutch means is provided between the engine and the motor, the clutch is connected when the engine is automatically stopped. When the clutch is disengaged, the rotation of the engine is stopped at a predetermined stop crank angle suitable for starting the engine by the load generated by the alternator when the clutch is disengaged.

  Thus, when the clutch is connected, the rotation of the engine can be stopped without using the alternator by using the torque of the motor connected to the engine. On the other hand, when the clutch is disengaged, the rotation of the engine can be stopped by the alternator without applying the mass load of the motor.

  Thus, by using together the motor which is a drive source, and the alternator which produces electric power using the driving force of an engine, the burden of both apparatuses concerning engine rotation stop control can be distributed. Thereby, durability and reliability of both apparatuses can be improved, and an alternator can be prevented from being enlarged. Then, by stopping the rotation of the engine at a predetermined stop crank angle suitable for starting the engine, a quick restart can be performed after the engine is automatically stopped.

  According to the control apparatus for a hybrid electric vehicle of claim 2, even when the clutch means is connected when the engine is automatically stopped, the charge amount of the battery that supplies power to the motor (hereinafter referred to as SOC: State Of) When (Charge) is larger than a predetermined upper limit charge amount (hereinafter referred to as SOC upper limit value), the clutch means is disconnected and the engine is stopped by the alternator.

That is, when the SOC of the battery is high, it is possible to prevent the battery from being overcharged by disengaging the clutch means and stopping the rotation of the engine using the alternator without using the motor. As a result, the durability and reliability of the motor can be ensured more reliably.
According to the hybrid electric vehicle control apparatus of the third aspect, the predetermined stop crank angle is determined by the cranking by the motor when the SOC of the battery is equal to or greater than the first predetermined charge amount (hereinafter referred to as the first predetermined SOC). If the SOC of the battery is less than the first SOC, the second stop crank angle is suitable for cranking by the starter.

Thereby, when the SOC of the battery is sufficient, the startability of the engine when the engine is restarted by the motor can be improved, and when the SOC of the battery is relatively low, the starter does not use the motor. The startability of the engine when the engine is restarted can be improved.
According to the control apparatus for a hybrid electric vehicle of claim 4, when the clutch means is connected at the time of automatic engine stop, the SOC of the battery is the second predetermined charge amount (hereinafter referred to as the second predetermined SOC). In the case above, the rotation of the engine is stopped by the driving torque of the motor, and when it is less than the second predetermined SOC, the rotation of the engine is stopped by the regenerative torque of the motor.

  That is, when the SOC of the battery is relatively high, the rotation of the engine is stopped at a predetermined stop crank angle by adjusting the engine to the advance side using the motor driving torque that consumes electric power. On the other hand, when the SOC of the battery is relatively low, the rotation of the engine is stopped at a predetermined stop crank angle by adjusting the engine to the retard side using the regenerative torque of the motor that generates power. Thereby, the engine rotation can be stopped by the motor while maintaining the SOC of the battery appropriately.

It is a schematic block diagram of the control apparatus of the hybrid electric vehicle which concerns on one Embodiment of this invention. It is a flowchart which shows the engine automatic stop control routine which integrated ECU of the control apparatus of the hybrid electric vehicle which concerns on one Embodiment of this invention performs. It is a flowchart which shows the engine rotation stop control routine which integrated ECU of the control apparatus of the hybrid electric vehicle which concerns on one Embodiment of this invention performs. It is a flowchart which shows the modification of the engine rotation stop control routine which integrated ECU performs. It is a flowchart which shows the modification of the engine automatic stop control routine which integrated ECU performs.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing a schematic configuration of a control apparatus for a hybrid electric vehicle according to an embodiment of the present invention, which will be described with reference to FIG.
A vehicle 1 shown in FIG. 1 is a hybrid electric vehicle including an engine 2 and a motor 4 as drive sources.

The engine 2 is an internal combustion engine that is generally used for automobiles, such as a diesel engine or a gasoline engine, and is not particularly limited here.
A clutch 6 is provided between the engine 2 and the motor 4. The output shaft of the engine 2 is connected to the input shaft of the clutch 6, and the rotary shaft of the motor 4 is connected to the output shaft of the clutch 6. ing.

The motor 4 is, for example, a permanent magnet type synchronous motor that can generate power, and the rotating shaft of the motor 4 is connected to the input shaft of the transmission 8. The drive force is transmitted from the output shaft of the transmission 8 to the left and right drive wheels 16 via the propeller shaft 10, the differential device 12, and the drive shaft 14.
The motor 4 is connected to a high voltage battery 18 mounted on the vehicle 1 via an inverter 20 and receives a power supply from the high voltage battery 18 to generate drive torque. The high voltage battery 18 is, for example, a secondary battery such as lithium ion or nickel metal hydride, and the inverter 20 converts the DC power from the high voltage battery 18 into AC power and supplies the motor 4 with power. On the other hand, when the vehicle is decelerated, the motor 4 functions as a generator and is regeneratively driven. That is, the motor 4 generates AC power by the driving force transmitted in reverse from the driving wheel 16, and a deceleration resistance is given to the driving wheel 16 by the regenerative torque generated by the motor 4 at this time. Then, the AC power is converted into DC power by the inverter 20 and then charged to the high voltage battery 18 so that the kinetic energy due to the rotation of the drive wheels 16 is recovered as electric energy.

In the vehicle 1 having such a configuration, only the rotating shaft of the motor 4 is mechanically connected to the drive wheels 16 via the transmission 8 when the clutch 6 is in a disconnected state. That is, only the drive torque generated by the motor 4 is transmitted to the drive wheels 16 as the drive torque of the vehicle 1.
On the other hand, when the clutch 6 is in the connected state, the output shaft of the engine 2 is mechanically connected to the transmission 8, the drive wheels 16 and the like via the rotating shaft of the motor 4. That is, when the torque generated by the motor 4 at this time is 0 and only the engine 2 is operated, only the driving torque generated by the engine 2 becomes the driving torque of the vehicle 1. If the motor 4 is also operated, the sum of the driving torque of the motor 4 and the driving torque of the engine 2 becomes the driving torque of the vehicle 1.

In the vehicle 1, an integrated ECU (electronic control unit) 30 that integrally controls the engine 2, the motor 4, the clutch 6, and the transmission 8 to perform various controls such as adjustment of torque distribution of the engine 2 and the motor 4. Is installed.
The integrated ECU 30 is communicably connected to each engine 2, the motor 4, the clutch 6, and the control unit (not shown) of the transmission 8 using a CAN (Controller Area Network).

  Further, the engine 2 is transmitted with a driving force of the engine 2 via a belt (not shown) and rotated to generate an alternator 32 that generates electric power, a starter 34 that performs cranking for starting the engine via a gear, and the engine 2. A crank angle sensor 36 for detecting the crank angle, an alternator 32, a low voltage battery 40 connected to the starter 34, and the like are provided. The alternator 32 can charge the generated power to the low voltage battery 40, and the starter 34 cranks the engine 2 by supplying power from the low voltage battery 40.

  In the present embodiment, the alternator 32 and the starter 34 are connected to the low voltage battery 40, but may be connected to the high voltage battery 18. In that case, a DC / DC converter capable of stepping up and stepping down the voltage is provided between the alternator 32 and the starter 34 and the high voltage battery 18 to convert the voltage supplied from each.

Further, the vehicle 1 is provided with a shift position sensor 38 that detects a shift position selected by the driver. As the shift position, there are a P range selected when parking, an N range where the gear of the transmission 8 is neutral, a D range selected when traveling, and the like.
The integrated ECU 30 is connected to the alternator 32, starter 34, crank angle sensor 36, and shift position sensor 38 via various control units or directly using CAN or the like. The integrated ECU 30 controls power generation by the alternator 32 so as to generate a predetermined power generation current in the alternator 32, and controls the cranking by the starter 34 by supplying power from the low voltage battery 40 to the starter 34.

Further, the integrated ECU 30 acquires crank angle information detected by the crank angle sensor 36, and calculates the engine speed based on the crank angle information.
Further, the integrated ECU 30 acquires the shift position information detected by the shift position sensor 38, the connection / disconnection information of the clutch 6 from the clutch 6, the SOC (charge amount) information of the high-voltage battery 18, and the like. The clutch 6 is connected / disconnected, the torque distribution of the engine 2 and the motor 4 is selected, and the gear position of the transmission 8 is selected according to the driving state.

  Then, the integrated ECU 30 in this embodiment performs so-called engine automatic stop control (idle stop) that stops fuel supply to the engine 2 when a predetermined engine automatic stop condition is satisfied (engine fuel supply stop control). means). Furthermore, the integrated ECU 30 restarts the engine 2 by restarting the engine 2 by cranking the engine 2 when a predetermined engine automatic start condition is satisfied after the engine 2 is automatically stopped. Start control (auto start) is performed. Thus, the integrated ECU 30 performs so-called engine automatic stop / restart (idle stop / auto start) control.

  Here, the predetermined engine automatic stop condition is, for example, a state in which the vehicle speed is substantially 0, the brake pedal is depressed, and the accelerator pedal is not depressed. The predetermined engine automatic start condition is a state where the engine automatic stop condition is not satisfied, that is, when the brake pedal is released or the accelerator pedal is depressed.

In the vehicle 1, it is possible to use the starter 34 for cranking the engine 2 when the clutch 6 is in the disconnected state, and use the starter 34 or the motor 4 when the clutch 6 is in the connected state. .
Further, in the engine automatic stop control, the integrated ECU 30 performs engine rotation stop control for stopping the rotation of the engine 2 at a predetermined stop crank angle suitable for starting the engine 2 (engine rotation stop control means).

Specifically, the engine automatic stop control performed by the integrated ECU 30 will be described below.
Referring to FIG. 2, there is shown a flowchart showing an engine automatic stop control routine executed by the integrated ECU 30, which will be described below with reference to the flowchart.

First, as step S1, the integrated ECU 30 determines whether or not the above-described engine automatic stop condition is satisfied. If the determination result is false (No), the routine is returned. On the other hand, if the determination result is true (Yes), the process proceeds to the next step S2 in order to perform engine automatic stop control.
As step S2, the integrated ECU 30 determines whether or not the shift position detected by the shift position sensor 38 is a P range or an N range that is a non-traveling range. If the determination result is false (No), that is, if the shift position is a travel range such as the D range, the process proceeds to step S3.

In step S <b> 3, the integrated ECU 30 controls to disengage the clutch 6 in order to prevent the driving force of the engine 2 from being transmitted to the drive wheels 16 when the vehicle stops in the travel range. At this time, if the clutch 6 has already been disengaged, the disengaged state is maintained.
In subsequent step S4, the ECU 30 determines whether or not a predetermined time has elapsed since the engine automatic stop condition was satisfied. If the determination result is false (No), the determination in step S4 is repeated. Although not shown, when the engine automatic stop condition is not satisfied during this time, the routine is returned. On the other hand, if the determination result is true (Yes), the process proceeds to step S5.

In step S <b> 5, the integrated ECU 30 stops the fuel supply to the engine 2.
In step S6, the integrated ECU 30 executes engine rotation stop control using an alternator 32, which will be described later, and ends the routine.
On the other hand, if the determination result in step S2 is true (Yes), that is, if the shift position is in the non-traveling range, the process proceeds to step S7.

In step S7, the integrated ECU 30 controls the clutch 6 to be connected because the shift position is in the non-traveling range and the driving force of the engine 2 is not transmitted from the transmission 8 to the driving wheels. At this time, when the clutch 6 is already connected, the connected state is maintained.
In the following step S8, the integrated ECU 30 determines whether or not a predetermined time has elapsed since the engine automatic stop condition was established, as in step S4. If the determination result is false (No), the determination in step S8 is repeated, and if the determination result is true (Yes), the process proceeds to step S9.

In step S9, the integrated ECU 30 acquires the SOC information from the high voltage battery 18, and determines whether or not the acquired SOC information is less than a predetermined SOC upper limit value (predetermined upper limit charge amount). The predetermined SOC upper limit value is set as a threshold value for preventing overcharging of the high voltage battery 18.
If the determination result is false (No), that is, if the SOC is greater than or equal to a predetermined SOC upper limit value, the process proceeds to step S10. In step S10, the integrated ECU 30 disconnects the clutch 6, proceeds to step S5, stops the fuel supply to the engine 2, executes engine rotation stop control using the alternator 32 in step S6, and ends the routine. .

On the other hand, if the determination result in step S9 is true (Yes), that is, if the SOC is less than the predetermined SOC upper limit value, the process proceeds to step S11.
In step S11, the integrated ECU 30 stops the fuel supply to the engine 2 as in step S5.
In step S12, the integrated ECU 30 executes engine rotation stop control using a motor 4 to be described later, and the routine ends.

Here, the engine rotation stop control in step S6 and step S12 will be described in detail.
Referring to FIG. 3, there is shown a flowchart showing an engine rotation stop control routine performed by the integrated ECU 30, which will be described below based on the flowchart. The engine rotation stop control using the alternator 32 in step S6 and the engine rotation stop control using the motor 4 in step S12 have the same control flow, and both will be described based on the flowchart of FIG. .

First, as step S <b> 20, the integrated ECU 30 acquires crank angle information detected by the crank angle sensor 36.
In step S21, the integrated ECU 30 calculates the engine speed based on the crank angle information, and determines whether or not the engine speed is less than a predetermined speed. The predetermined rotation speed is set to a rotation speed (for example, 10 to 20 rpm) at which the engine rotation can be quickly stopped by the power generation load of the alternator 32 or the regenerative torque of the motor 4, for example. If the determination result is false (No), the process returns to step S20, crank angle information is acquired again, and the determination in step S21 is repeated. On the other hand, if the determination result is true (Yes), the process proceeds to the next step S22.

In step S22, the integrated ECU 30 stops the engine rotation at a predetermined stop crank angle suitable for starting.
Here, as means for stopping the engine rotation, in the case of the engine rotation stop control in the step S6, due to the load accompanying the power generation of the alternator 32, in the case of the engine rotation stop control in the step S12, due to the regenerative torque of the motor 4, respectively. The rotation of the engine 2 is stopped at a predetermined stop crank angle by applying a force in a direction in which the rotation of the engine 2 is stopped (retarded side).

  More specifically, in the case where the alternator 32 is used, the integrated ECU 30 instructs the alternator 32 to generate power, and the alternator 32 generates power in accordance with the instruction so as to apply a load to the engine 2 and set a predetermined stop crank. The rotation of the engine 2 is stopped at an angle. On the other hand, when using the motor 4, the integrated ECU 30 instructs the motor 4 to generate regenerative torque, and the motor 4 generates regenerative torque in accordance with the instruction so that the engine 2 is loaded and predetermined. The rotation of the engine 2 is stopped at the stopped crank angle.

  The predetermined stop crank angle is set to a crank angle corresponding to a piston position at which the load required for cranking by the starter 34 is minimized in any cylinder of the engine 2, for example. Specifically, as the stop crank angle suitable for cranking by the starter 34, it is preferable that the crank angle at which the piston position is near the bottom dead center in the cylinder in the late intake stroke or the early compression stroke is set as the stop crank angle.

In step S22, the integrated ECU 30 stops the rotation of the engine 2 and then ends the control routine.
As described above, the integrated ECU 30 stops the rotation of the engine 2 without using the alternator 32 by using the torque of the motor 4 connected to the engine 2 when the clutch 6 is connected. Can do. On the other hand, when the clutch 6 is disconnected, the rotation of the engine can be stopped by the alternator 32 without applying the mass load of the motor 4.

  Thus, by using together the motor 4 which is a drive source, and the alternator 32 which produces electric power using the drive force of the engine 2, the burden of both apparatuses concerning engine rotation stop control can be disperse | distributed. Thereby, durability and reliability of both apparatuses can be improved, and the enlargement of the alternator 32 can also be prevented. Then, by stopping the rotation of the engine 2 at a predetermined stop crank angle suitable for starting the engine 2, a quick restart can be performed after the engine is automatically stopped.

Further, when the SOC of the high voltage battery 18 is higher than the predetermined SOC upper limit value, the motor 2 is stopped using the alternator 32 without using the motor 4, so that the excessive voltage of the high voltage battery 18 is exceeded. Charging can be prevented. Thereby, durability and reliability of the motor 4 can be ensured more reliably.
Although the description of the embodiment of the control apparatus for a hybrid electric vehicle according to the present invention is finished above, the embodiment is not limited to the above embodiment.

  In the above embodiment, the predetermined stop crank angle is a crank angle suitable for cranking by the starter 34, but the predetermined stop crank angle is not limited to this. For example, when the vehicle 1 can start the engine 2 by the motor 4, the predetermined stop crank angle may be a stop crank angle suitable for cranking using the motor 4. Specifically, in the cylinder in the compression stroke, it is preferable to set the crank angle at which the piston position is an intermediate position from the bottom dead center to the top dead center.

Further, in the case of the configuration of the vehicle 1 in which the engine 2 can be started by either the motor 4 or the starter 34, the predetermined stop crank angle is switched according to the SOC of the high voltage battery 18. It doesn't matter.
Specifically, referring to FIG. 4, there is shown a flowchart showing a modified example of the engine rotation stop control routine executed by the integrated ECU 30. A modified example of the engine rotation stop control will be described with reference to FIG. In this modification, the engine automatic stop control routine shown in FIG. 2 is the same as that in the above embodiment, and the description thereof is omitted.

  Steps S30 and S31 in FIG. 4 are the same as steps S20 and S21 in FIG. 3 in the above-described embodiment, and the integrated ECU 30 acquires crank angle information and performs step S30 until the engine speed becomes smaller than a predetermined speed. , S31 is repeated. If the determination result is true (Yes), the process proceeds to step S32.

  In step S32, the integrated ECU 30 determines whether or not the SOC of the high voltage battery 18 is equal to or higher than a predetermined first predetermined SOC. The first predetermined SOC is set as a threshold value at which the engine 2 can be stably started by cranking by the motor 4. If the determination result is true (Yes), the process proceeds to step S33.

  In step S33, the integrated ECU 30 stops the rotation of the engine 2 at the first stop crank angle suitable for cranking by the motor 4, and ends the routine. The first stop crank angle is preferably a crank angle at which the piston position is an intermediate position from the bottom dead center to the top dead center in the cylinder in the compression stroke described above, for example.

On the other hand, if the determination result in step S32 is false (No), that is, if the SOC is less than the first predetermined SOC, the process proceeds to step S34.
In step S34, the integrated ECU 30 stops the rotation of the engine 2 at a second stop crank angle suitable for cranking by the starter 34, and ends the routine. The second stop crank angle is preferably a crank angle at which the piston position is in the vicinity of the bottom dead center in the cylinder in the late stage of the intake stroke or the early stage of the compression stroke, for example, similarly to the predetermined stop crank angle in the above embodiment.

  Note that, in the case of the engine rotation stop control in step S6 of FIG. 2, the means for stopping the engine rotation in steps S33 and S34 is the engine rotation stop in step S12 due to the load accompanying the power generation of the alternator 32. In the case of control, the rotation of the engine 2 is stopped at a predetermined stop crank angle by applying a force in a direction to stop the rotation of the engine 2 by the regenerative torque of the motor 4.

As described above, in the engine rotation stop control in the modification, the predetermined stop crank angle is set to the first stop crank angle suitable for motor start according to the SOC of the high voltage battery 18 and the second stop crank angle suitable for starter start. The stop crank angle is properly used.
Thereby, when the SOC of the high voltage battery 18 is sufficient, the startability of the engine 2 when starting by the motor 4 can be improved, and when the SOC of the high voltage battery 18 is relatively low, the motor The startability of the engine 2 by the starter 34 that does not use 4 can be improved.

  In the above embodiment, a predetermined SOC upper limit value is set, and when the SOC is equal to or higher than the SOC upper limit value, the clutch 6 is disengaged and the engine rotation stop control using the alternator 32 is switched. The proper use of the means for stopping the engine rotation is not limited to this. For example, when the rotation of the engine 2 is stopped using the motor 4, the driving torque and the regenerative torque of the motor 4 may be switched according to the SOC.

Specifically, referring to FIG. 5, there is shown a flowchart showing a modified example of the engine automatic stop control routine executed by the integrated ECU 30. A modified example of the engine automatic stop control will be described with reference to FIG.
Steps S40 and S41 in FIG. 5 are the same as steps S1 and S2 in FIG. 2 in the above embodiment. If the engine automatic stop condition is satisfied and the travel range is the travel range, the process proceeds to step S42. In step S42, control similar to that in steps S3 to S6 in FIG. 2 in the above embodiment is performed, and detailed description thereof is omitted.

On the other hand, if the determination result in step S41 is true (Yes), the process proceeds to step S43.
Steps S43 to S45 are the same as steps S7, S8, and S11 of FIG. 2 in the above embodiment, and the integrated ECU 30 connects the clutch 6 (S43), and after a predetermined time has passed (S44), The fuel supply is stopped (S44).

In step S46, the integrated ECU 30 determines whether the SOC of the high voltage battery 18 is less than a predetermined second predetermined SOC. The second predetermined SOC is a threshold value for preventing overcharging of the high voltage battery 18, and may be set to the predetermined SOC upper limit value in the above-described embodiment, for example.
If the determination result is true (Yes), that is, if the SOC is less than the second predetermined SOC and the SOC is relatively low, the process proceeds to step S47.

In step S47, the engine rotation stop control using the regenerative torque of the motor 4 is executed, and the routine ends. That is, in step S47, the rotation of the engine 2 is stopped at a predetermined stop crank angle by applying a force in a direction (retard side) to stop the rotation of the engine 2 by the regenerative torque of the motor 4.
On the other hand, if the determination result in step S46 is false (No), that is, if the SOC is equal to or higher than the second predetermined SOC and the SOC is relatively high, the process proceeds to step S48.

In step S48, engine rotation stop control using the drive torque of the motor 4 is executed, and the routine is terminated. That is, in step S47, the rotation of the engine 2 is stopped at a predetermined stop crank angle by applying a force in a direction (advance side) that promotes the rotation of the engine 2 by the driving torque of the motor 4.
As for the specific engine rotation stop control, either the control shown in FIG. 3 in the above embodiment or the control shown in FIG. 4 as a modified example is performed.

  Thus, in the engine automatic stop control in the modification, when the SOC of the high voltage battery 18 is relatively high, the engine 2 is adjusted to the advance side using the driving torque of the motor 4 that consumes power. The rotation of the engine 2 is stopped at a predetermined stop crank angle. On the other hand, when the SOC of the battery is relatively low, the rotation of the engine 2 is stopped at a predetermined stop crank angle by adjusting the engine 2 to the retard side using the regenerative torque of the motor 4 that generates power. Thereby, the engine rotation can be stopped by the motor 4 while maintaining the SOC of the battery appropriately.

  Further, in the above embodiment, the rotation of the engine 2 is stopped at a predetermined stop crank angle using the motor 4 or the alternator 32, but means for stopping the engine 2 at the predetermined stop crank angle is limited to this. Instead, anything that can adjust the engine rotation is acceptable. For example, a starter 34 may be used in place of the alternator 32, and the engine 2 may be loaded by the starter 34 or may be advanced to a predetermined stop crank angle by supplying power to the starter 34 and cranking. Absent.

1 vehicle 2 engine 4 motor 6 clutch (clutch means)
30 integrated ECU (engine fuel supply stop control means, engine rotation stop control means)
32 Alternator 34 Starter 36 Crank angle sensor 38 Shift position sensor

Claims (4)

A control device for a hybrid electric vehicle capable of selecting an engine and a motor as a drive source,
An alternator that generates electric power using the driving force of the engine;
Clutch means provided between the engine and the motor, for connecting and disconnecting the driving force of the engine transmitted from the engine to the driving wheels via the motor;
Engine fuel supply stop control means for stopping fuel supply to the engine when a predetermined engine automatic stop condition is satisfied;
When the predetermined engine automatic stop condition is satisfied,
When the clutch means is in the connected state, the rotation of the engine is stopped at a predetermined stop crank angle suitable for starting the engine by the torque generated by the motor,
When the clutch means is in a disengaged state, engine rotation stop control means for stopping the rotation of the engine at a predetermined stop crank angle suitable for starting the engine from a load accompanying power generation of the alternator;
A control apparatus for a hybrid electric vehicle, comprising: The engine rotation stop control means includes
When the clutch is in the connected state and the charge amount of the battery that supplies power to the motor is equal to or greater than a predetermined upper limit charge amount, the clutch means is disengaged, and the load of the engine due to the power generation of the alternator is set. 2. The control apparatus for a hybrid electric vehicle according to claim 1, wherein the rotation of the engine is stopped at a predetermined stop crank angle suitable for starting. A starter provided in the engine for cranking the engine;
The engine rotation stop control means determines the predetermined stop crank angle as follows:
When the charge amount of the battery that supplies power to the motor is equal to or greater than a first predetermined charge amount, the first stop crank angle suitable for cranking by the motor is set,
2. The second stop crank angle suitable for cranking by the starter is set when a charge amount of a battery for supplying electric power to the motor is less than the first predetermined charge amount. 3. A control apparatus for a hybrid electric vehicle according to 1 or 2. The engine rotation stop control means, when the clutch means is in a connected state,
When the charge amount of the battery that supplies power to the motor is equal to or greater than a second predetermined charge amount, the engine is rotated at a predetermined stop crank angle suitable for starting the engine by the driving torque of the motor. Stop,
When the charge amount of the battery that supplies power to the motor is less than the second predetermined charge amount, the rotation of the engine is performed at a predetermined stop crank angle suitable for starting the engine by the regenerative torque of the motor. The hybrid electric vehicle control device according to claim 1, wherein the control device is stopped.

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