JP5125293B2 - Control device for hybrid vehicle - Google Patents

Description

  The present invention relates to a control apparatus for a hybrid vehicle that uses both an engine and a motor as a vehicle drive source.

As this type of technology, the technology described in Patent Document 1 is disclosed. In this publication, a hybrid vehicle control device is disclosed that includes an automatic speed control device that maintains a constant vehicle travel speed and inter-vehicle distance.
JP 2004-270512 A

  In the above prior art, the driving wheel is driven by the driving force generated by the engine from the motor driving mode in which the driving wheel is driven only by the driving force of the driving motor by returning the set vehicle speed or increasing the driving resistance by climbing during automatic driving. Transition to the driving engine running mode. However, when the driving in the engine running mode is performed for a short time, there is a problem that the engine starts frequently and the fuel consumption may be deteriorated.

  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 that can suppress engine driving for a short time and improve fuel efficiency.

  In order to achieve the above object, in the hybrid vehicle control apparatus of the present invention, when the mode transition predicting unit predicts that the motor traveling mode, the hybrid traveling mode, and the motor traveling mode are shifted in this order, the motor traveling mode by the mode switching unit is used. And a mode switching prohibiting means for prohibiting switching from the hybrid travel mode to the hybrid travel mode.

  Therefore, repeated starting and stopping of the engine can be suppressed, and fuel consumption can be improved.

  Hereinafter, the best mode for realizing a control device for a hybrid vehicle of the present invention will be described based on Embodiments 1 to 4.

[Configuration of hybrid vehicle]
FIG. 1 is a system diagram of a hybrid vehicle 1 according to the first embodiment. In FIG. 1, a thick solid line indicates driving force transmission, a thick dotted line indicates a high electric circuit, a thin solid line indicates a weak electric circuit, and a one-dot chain line indicates a hydraulic circuit.
The drive system of the hybrid vehicle 1 has an engine 2 and a drive motor 3 as power sources, a power split mechanism 4 as a transmission, and a generator 5 that generates electric power.

  The power split mechanism 4 has a planetary gear. The engine 2 is connected to the carrier, the drive motor 3 is connected to the ring gear, and the generator 5 is connected to the sun gear. The output shaft 6 connected to the sun gear of the power split mechanism 4 transmits power to the final drive 7. The final drive 7 decelerates the rotation of the output shaft 6 and transmits power to the drive shaft 9 connected to the left and right drive wheels 8.

  The high-voltage system of the hybrid vehicle 1 includes a high-power battery 11, an electric air conditioner 12 that is driven by the supply of high-power, a DC / DC converter 13 that converts high-power into low-power, a drive motor 3, and a generator 5. And an inverter 14 for controlling electric power. The inverter 14 supplies power from the high-power battery 11 to the drive motor 3 and charges the high-power battery 11 with power generated by the generator 5. The DC / DC converter 13 drops the voltage of the high voltage battery 11 and charges the auxiliary battery 15.

  The hydraulic system of the hybrid vehicle 1 has a brake actuator 31 and a mechanical brake 32. The brake fluid pressure generated by the brake actuator 31 is transmitted to the mechanical brakes 32 provided on the driving wheels 8 and the driven wheels 10 to generate a braking force.

  The control system of the hybrid vehicle 1 includes a controller 21 that controls each device and sensors that detect various types of vehicle information. The controller 21 receives various vehicle information from each sensor, charging information (State Of Charg: SOC) from the high-power battery 11 and auxiliary battery 15, output power information from the DC / DC converter 13, and the electric air conditioner 12. The driving state information is input. Calculation is performed based on the input information, and the engine 2, inverter 14, high-power battery 11, electric air conditioner 12, DC / DC converter 13, and brake actuator 31 are controlled according to the calculation result.

  As various sensors, a vehicle speed sensor 22 for detecting the speed of the own vehicle, an accelerator pedal sensor 23 for detecting the amount of depression of the accelerator pedal, a brake pedal sensor 24 for detecting the amount of depression of the brake pedal, the own vehicle and a preceding vehicle ( Or an inter-vehicle distance sensor 25 that detects the distance to the obstacle), a steering angle sensor 26 that detects the steering angle by steering the steering wheel, a GPS 27 that detects the position of the host vehicle, and the vehicle control state with other vehicles. It has a vehicle-to-vehicle communication device 28 for transmitting and receiving.

[Automatic running control function]
The controller 21 of the hybrid vehicle 1 has an automatic travel control function. This automatic travel control function is a function for controlling the vehicle so that the desired vehicle speed or the desired inter-vehicle distance is input by the driver and the desired vehicle speed or the desired inter-vehicle distance is maintained. The desired vehicle speed is selected from a range of 40 km / h to 100 km / h, for example, and the desired inter-vehicle distance is selected from, for example, three stages of “long”, “medium”, and “short”. When there is no preceding vehicle, automatic travel control is performed with the selected desired vehicle speed as the target vehicle speed. When there is a preceding vehicle, the target vehicle speed is set so that the selected desired inter-vehicle distance can be realized, and automatic traveling control is performed.

  The controller 21 sets a transition time from the current vehicle speed to the target vehicle speed according to the difference between the current vehicle speed and the target vehicle speed. A transition locus of the required torque is determined according to the transition time. FIG. 2 is a diagram showing a transition locus of the required torque with respect to the vehicle speed. 3A is a time chart of vehicle speed, and FIG. 3B is a time chart of required torque. Here, a combination of vehicle speed and torque is expressed as a driving point.

  For example, consider the transition of required torque from driving point A, which is the current vehicle speed Va, to driving points B, C, which are target vehicle speeds Vb, Vc. The torques at vehicle speeds Va, Vb, and Vc are Ta, Tb, and Tc, respectively. The automatic travel control function determines the target vehicle speed Vb according to the desired vehicle speed or the desired inter-vehicle distance selected by the driver. Transition times Δtab, Δtac from the current vehicle speed Va to the target vehicle speeds Vb, Vc are set according to the difference between the current vehicle speed Va and the target vehicle speeds Vb, Vc. In accordance with the transition times Δtab and Δtac, control is performed by determining the required torque transition locus as shown in FIGS. 2 and 3C.

[Driving mode switching]
The control unit 21 of the hybrid vehicle 1 switches between a motor travel mode that travels by the driving force of only the drive motor 3 as a travel mode and a hybrid travel mode that travels by the drive force of the drive motor 3 and the engine 2. The controller 21 switches between the motor travel mode and the hybrid travel mode according to the vehicle speed and the required torque.

  As shown in FIG. 2, a mode transition line that is a threshold value for switching between the motor travel mode and the hybrid travel mode is set. This mode transition line is a threshold value of the required torque set according to the vehicle speed. When the required torque is less than the mode transition line, the vehicle travels in the motor travel mode, and when it exceeds the mode transition line, the vehicle travels in the hybrid travel mode. This mode transition line is set in consideration of the rated output of the drive motor 3, the fuel consumption of the engine 2, the SOC of the high-power battery 11, and the like.

As described above, the automatic travel control function determines the required torque transition locus according to the current vehicle speed and the target vehicle speed. Therefore, the required torque trajectory can be predicted during automatic traveling. The time transition of the required torque when shifting from the operating point A to the operating points B and C by the automatic travel control function will be described with reference to FIG.
When shifting from the operating point A to the operating point B, as shown by the solid line in FIG. 3B, the required torque is less than the mode transition line before the time tb1, so the vehicle travels in the motor travel mode. At time tb1, since the required torque is equal to or higher than the mode transition line, the engine 2 is started and the vehicle travels in the hybrid travel mode. At time tb2, since the required torque becomes less than the mode transition again, the fuel supply to the engine 2 is stopped and the vehicle travels in the motor travel mode. That is, when shifting from the driving point A to the driving point B, the driving mode transitions in the order of motor driving mode → hybrid driving mode → motor driving mode.

  When shifting from the operating point A to the operating point C, as shown by the dotted line in FIG. 3B, the required torque is less than the mode transition line before the time tc1, and thus the vehicle travels in the motor travel mode. At time tc1, since the required torque is equal to or higher than the mode transition line, the engine 2 is started and the vehicle travels in the hybrid travel mode. Thereafter, the vehicle travels in the hybrid travel mode. That is, when shifting from the operating point A to the operating point C, the traveling mode changes in the order of motor traveling mode → hybrid traveling motor.

[Control processing of hybrid vehicle]
FIG. 4 is a flowchart showing the control process of the hybrid vehicle of the first embodiment in the controller 21.
In step S1, it is determined whether or not there is a preceding vehicle. If there is a preceding vehicle, the process proceeds to step S2, and if there is no preceding vehicle, the process ends.

In step S2, it is determined whether or not automatic traveling control is being performed. If automatic traveling control is being performed, the process proceeds to step S3. If automatic traveling control is not being performed, the processing is terminated.
In step S3, it is determined whether or not the required torque is increased in the motor travel mode (EV mode). If these two conditions are satisfied, the process proceeds to step S4, and either of these two conditions is satisfied. If not, the process ends.

  In step S4, it is determined whether or not the output limit value of the high-power battery 11 is equal to or greater than the threshold value. If the output limit value is equal to or greater than the threshold value, the process proceeds to step S5. The output limit value of the high-power battery 11 is set according to the temperature and SOC of the high-power battery 11.

  FIG. 5 is a graph showing the output limit value of the high-power battery 11, FIG. 5A shows the output limit value with respect to the temperature of the high-power battery 11, and FIG. 5B shows the output limit value with respect to the SOC of the high-power battery 11. . The output limit value with respect to the temperature of the high-power battery 11 is normally a value indicated by a solid line in FIG. 5A, but if it is instantaneous (for example, about 2 seconds), it is increased by several [kw] over the entire temperature range. Control with the value (dotted line in FIG. 5A) does not affect the durability of the high-power battery 11. In addition, the output limit value for the SOC of the high-power battery 11 is normally a value indicated by a solid line in FIG. 5B, but if it is instantaneous (for example, about 2 seconds), it is several [kw] in the area A, and the area B Then, even if the value is about 1.2 times the value indicated by the solid line (dotted line in FIG. 5B), the durability of the high-power battery 11 is not affected. In step 4, the values indicated by the dotted lines in FIGS. 5A and 5B are set as output limit values.

In step S5, it is determined whether or not the output of the auxiliary equipment such as the electric air conditioner 12 and the DC / DC converter 13 can be reduced. If the output can be reduced, the process proceeds to step S6 and cannot be reduced. If so, the process ends.
In step S6, it is determined from the required torque transition calculated by the controller 21 whether or not the mode transition is the motor travel mode (EV mode) → the hybrid travel mode (HEV mode) → the motor travel mode (EV mode). If it is the mode transition, the process proceeds to step S7, and if it is not the mode transition, the process is terminated.

  In step S7, it is determined whether or not the travel time in the hybrid travel mode is 2 seconds or less. If it is 2 seconds or less, the process proceeds to step S8, and if it is greater than 2 seconds, the process is terminated. The set value of 2 seconds is a value set so that the durability of the drive motor 3 and the high-power battery 11 is not affected even if the drive motor 3 is driven at the rated output or more, and is not limited to 2 seconds. What is necessary is just to set according to the performance of the drive motor 3 or the high-power battery 11.

  In step S8, the mode transition line is raised and the process proceeds to step S9. By raising the mode transition line, the motor travel mode is not switched to the hybrid mode even if the required torque becomes higher than the mode transition line before raising. The output of the drive motor 3 is set to be equal to or higher than the rating while the required torque is higher than the mode transition line before being increased. That is, in the hybrid travel mode, the torque output by the engine 2 and the drive motor 3 is output only by the drive motor 3.

In step S9, it is determined whether or not there is no preceding vehicle. If there is no preceding vehicle, the process is terminated. If there is a preceding vehicle, the process proceeds to step S10.
In step S10, it is determined whether or not the target vehicle speed has been reached. If the target vehicle speed has been reached, the process ends. If not, the process returns to step S9.

[Control action of hybrid vehicle]
FIG. 6 is a diagram illustrating a transition state of the required torque when the driving point A (vehicle speed Va, torque Ta) is shifted to the driving point B (vehicle speed Vb, torque Tb).

  When the mode transition line is at the position indicated by the solid line, when the driving point A shifts from the driving point A to the driving point B, the driving mode transitions in the order of motor driving mode → hybrid driving mode → motor driving mode. The engine 2 will be stopped again. Therefore, the engine 2 is repeatedly started and stopped, which may lead to deterioration in fuel consumption.

  The required torque transition can be predicted during automatic driving. For this reason, when the travel mode transitions in the order of motor travel mode → hybrid travel mode → motor travel mode due to the required torque transition predicted during automatic travel, switching to the hybrid travel mode is prohibited.

  FIG. 7A is a time chart of vehicle speed, and FIG. 7B is a time chart of required torque. As shown in FIG. 7B, when the mode transition line is at the position indicated by the solid line, the traveling mode is the hybrid traveling mode between time tb1 and time tb2. On the other hand, when the mode transition line is raised to the position indicated by the dotted line, switching to the hybrid travel mode is prohibited, and the travel mode is always the motor travel mode. Therefore, repeated starting and stopping of the engine 2 can be suppressed, and fuel consumption can be improved.

  Further, as a method of prohibiting switching from the motor travel mode to the hybrid travel mode, it is conceivable to reduce the required torque and lengthen the transition time from the current vehicle speed to the target vehicle speed. However, if the transition time from the current vehicle speed to the target vehicle speed is lengthened, sufficient acceleration performance cannot be obtained. Moreover, it will drive only with the drive motor 3 for a long time, and the durability of the drive motor 3 will deteriorate. In addition, the SOC of the high-power battery 11 decreases quickly, and it is necessary to start the engine 2 for charging.

Therefore, in the first embodiment, the automatic travel function of the controller 21 is determined based on the difference between the current vehicle speed and the target vehicle speed to determine the transition time until the transition from the current vehicle speed to the target vehicle speed.
Therefore, sufficient acceleration performance can be obtained. Further, it is possible to avoid traveling in the motor travel mode for a long time, and the durability of the drive motor 3 can be improved.

  As shown in FIG. 7B, when the mode transition line is raised to the position indicated by the dotted line, the torque normally secured by the engine 2 and the drive motor 3 needs to be secured only by the drive motor 3. If the torque is secured only by the drive motor 3 for a long time, the durability of the drive motor 3 is deteriorated. Further, since the energy efficiency is deteriorated, the SOC of the high-power battery 11 is rapidly reduced, so that it is necessary to start the engine 2 for charging, and the fuel consumption may be deteriorated.

  Therefore, in the first embodiment, when the time for traveling in the hybrid travel mode (from time tb1 to time tb2 in FIG. 7B) exceeds the set time (for example, 2 seconds), switching to the hybrid travel mode is permitted. I tried to do it.

  Therefore, it is possible to suppress the securing of torque only by the drive motor 3 in a short time, and the durability of the drive motor 3 can be improved. Further, energy efficiency can be improved, and fuel consumption can be improved.

  In the first embodiment, when the time for traveling in the hybrid travel mode (from time tb1 to time tb2 in FIG. 7B) is less than the set time (for example, 2 seconds), switching to the hybrid travel mode is prohibited. I did it.

  Even if the output of the drive motor 3 is set to the rated value or more for a short time, the durability of the drive motor 3 or the high-power battery 11 is not affected. Therefore, while ensuring the durability of the drive motor 3 and the high-power battery 11, it is possible to suppress repeated starting and stopping of the engine 2 and improve fuel efficiency.

When traveling in the hybrid travel mode is prohibited, sufficient acceleration performance cannot be ensured unless the output of the drive motor 3 satisfies the required torque.
Therefore, the output of the drive motor 3 is prohibited from exceeding the mode transition line while ensuring the required torque.
Therefore, the output of the drive motor 3 satisfies the required torque, and it is possible to prohibit the hybrid travel mode while ensuring sufficient acceleration performance.

Also, the mode transition line is raised in order to prohibit the required torque from exceeding the mode transition line.
Therefore, the hybrid travel mode can be prohibited without changing the required torque, and the output of the drive motor 3 can satisfy the required torque and ensure sufficient acceleration performance.

  In the first embodiment, whether or not the mode transition is the motor travel mode → the hybrid travel mode → the motor travel mode is determined based on the required torque transition calculated by the controller 21. Furthermore, when the travel time in the hybrid travel mode is 2 seconds or less from the calculated required torque transition, switching to the hybrid travel mode is prohibited.

  In the second embodiment, from the required torque transition calculated in the controller 21, when the time integral value of the required torque in the hybrid travel mode is equal to or greater than the set value, the switch to the hybrid travel mode is prohibited. Different from Example 1.

  The hybrid vehicle control device of the second embodiment has the same configuration as that of the first embodiment, but differs in the processing performed in the controller 21. The same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted.

[Control processing of hybrid vehicle]
FIG. 8 is a flowchart showing a control process of the hybrid vehicle of the second embodiment in the controller 21.
In step S11, it is determined whether or not there is a preceding vehicle. If there is a preceding vehicle, the process proceeds to step S12. If there is no preceding vehicle, the process ends.

In step S12, it is determined whether or not automatic traveling control is being performed. If automatic traveling control is being performed, the process proceeds to step S13. If automatic traveling control is not being performed, the processing is terminated.
In step S13, it is determined whether or not the required torque is increased in the motor travel mode (EV mode). If these two conditions are satisfied, the process proceeds to step S14, and either of these two conditions is satisfied. If not, the process ends.

  In step S14, it is determined whether or not the output limit value of the high-power battery 11 is equal to or greater than the threshold value. If the output limit value is equal to or greater than the threshold value, the process proceeds to step S15. The output limit value of the high-power battery 11 is set according to the temperature and SOC of the high-power battery 11.

In step S15, it is determined whether or not the output of the auxiliary equipment such as the electric air conditioner 12 and the DC / DC converter 13 can be reduced. If the output can be reduced, the process proceeds to step S16 and cannot be reduced. If so, the process ends.
In step S16, the time integral value of the required torque during travel in the hybrid travel mode is calculated from the required torque transition calculated in the controller 21, and the process proceeds to step S17.

  In step S17, it is determined whether or not the time integral value of the required torque is equal to or less than the set value. If it is equal to or less than the set value, the process proceeds to step S18, and if greater than the set value, the process ends. This set value is a value set so as not to affect the durability of the drive motor 3 or the high-power battery 11 even if the drive motor 3 is driven at a rated output or more.

  In step S18, the mode transition line is raised and the process proceeds to step S19. By raising the mode transition line, the motor travel mode is not switched to the hybrid mode even if the required torque becomes higher than the mode transition line before raising. The output of the drive motor 3 is set to be equal to or higher than the rating while the required torque is higher than the mode transition line before being increased. That is, in the hybrid travel mode, the drive motor 3 outputs the amount that the engine 2 should output.

In step S19, it is determined whether or not there is no preceding vehicle. If there is no preceding vehicle, the process is terminated. If there is a preceding vehicle, the process proceeds to step S20.
In step S20, it is determined whether or not the target vehicle speed has been reached. If the target vehicle speed has been reached, the process ends. If not, the process returns to step S19.

[Control action of hybrid vehicle]
FIG. 9A is a time chart of vehicle speed, and FIG. 9B is a time chart of required torque.
The work amount of the drive motor 3 is a time integral value of the output torque. If the amount of work of the drive motor 3 increases, the durability of the drive motor 3 may deteriorate.

Therefore, in the second embodiment, when the time integral value of the required torque in the motor travel mode (the hatched portion in FIG. 9B) is equal to or greater than the set value, switching to the hybrid travel mode is permitted.
Therefore, an increase in the work amount by the drive motor 3 can be suppressed, and the durability of the drive motor 3 can be improved.

In the first embodiment, it is prohibited to raise the mode transition line and switch from the motor travel mode to the hybrid travel mode.
The third embodiment is different from the first embodiment in that the required torque is suppressed and switching from the motor travel mode to the hybrid travel mode is prohibited.

  The hybrid vehicle control device of the third embodiment has the same configuration as that of the first embodiment, but differs in the processing performed in the controller 21. The same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted.

[Control processing of hybrid vehicle]
FIG. 10 is a flowchart showing the control process of the hybrid vehicle of the third embodiment in the controller 21.
In step S21, it is determined whether or not there is a preceding vehicle. If there is a preceding vehicle, the process proceeds to step S22, and if there is no preceding vehicle, the process ends.

In step S22, it is determined whether or not automatic traveling control is being performed. If automatic traveling control is being performed, the process proceeds to step S23, and if automatic traveling control is not being performed, the processing is terminated.
In step S23, it is determined whether or not the required torque is increased in the motor travel mode (EV mode). If these two conditions are satisfied, the process proceeds to step S24, and either of these two conditions is satisfied. If not, the process ends.

  In step S24, it is determined whether or not the output limit value of the high-power battery 11 is equal to or greater than the threshold value. If the output limit value is equal to or greater than the threshold value, the process proceeds to step S25. The output limit value of the high-power battery 11 is set according to the temperature and SOC of the high-power battery 11.

In step S25, it is determined whether or not the output of the auxiliary equipment such as the electric air conditioner 12 and the DC / DC converter 13 can be reduced. If the output can be reduced, the process proceeds to step S26 and cannot be reduced. If so, the process ends.
In step S26, the time integral value of the required torque during travel in the hybrid travel mode is calculated from the required torque transition calculated in the controller 21, and the process proceeds to step S27.

  In step S27, it is determined whether or not the time integral value of the required torque is equal to or less than the set value. If it is equal to or less than the set value, the process proceeds to step S28, and if greater than the set value, the process ends. This set value is a value set so as not to affect the durability of the drive motor 3 or the high-power battery 11 even if the drive motor 3 is driven at a rated output or more.

  In step S28, the suppressed request torque is output as the suppressed request torque, and the process proceeds to step S29. The output of the suppression request torque prohibits the suppression request torque from exceeding the mode transition line. This suppression request torque is used only for switching determination of the travel mode, and the drive motor 3 is controlled according to the request torque. Therefore, normally, in the range in which the vehicle travels in the hybrid travel mode, the output of the drive motor 3 is set to be higher than the rating. That is, in the hybrid travel mode, the drive motor 3 outputs the amount that the engine 2 should output.

In step S29, it is determined whether or not there is no preceding vehicle. If there is no preceding vehicle, the process is terminated. If there is a preceding vehicle, the process proceeds to step S30.
In step S30, it is determined whether or not the target vehicle speed has been reached. If the target vehicle speed has been reached, the process ends. If not, the process returns to step S29.

[Control action of hybrid vehicle]
FIG. 11 is a diagram showing a transition state of the required torque with respect to the vehicle speed. FIG. 12A is a time chart of vehicle speed, and FIG. 12B is a time chart of required torque.
Sufficient acceleration performance cannot be ensured if the output of the drive motor 3 does not satisfy the required torque when traveling in the hybrid travel mode is prohibited in order to suppress repeated starting and stopping of the engine 2.

  Therefore, in the third embodiment, the required suppression torque that suppresses the required torque is output. As shown in FIGS. 11 and 12 (b), the suppression request torque does not exceed the mode transition line, and therefore it is possible to prohibit switching from the motor travel mode to the hybrid travel mode. Further, since the drive motor 3 is controlled based on the required torque, the output of the drive torque satisfies the required torque, and sufficient acceleration performance can be ensured.

In the first embodiment, it is prohibited to raise the mode transition line and switch from the motor travel mode to the hybrid travel mode.
The fourth embodiment is different from the first embodiment in that it is prohibited or permitted to switch from the motor travel mode to the hybrid travel mode from the current vehicle speed and the target vehicle speed using a map.

  The hybrid vehicle control device of the fourth embodiment has the same configuration as that of the first embodiment, but differs in the processing performed in the controller 21. The same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted.

[Control processing of hybrid vehicle]
FIG. 13 is a flowchart showing the control process of the hybrid vehicle of the fourth embodiment in the controller 21.
In step S31, it is determined whether or not there is a preceding vehicle. If there is a preceding vehicle, the process proceeds to step S32. If the preceding vehicle does not exist, the process ends.

In step S32, it is determined whether or not automatic traveling control is being performed. If automatic traveling control is being performed, the process proceeds to step S33, and if automatic traveling control is not being performed, the processing is terminated.
In step S33, it is determined whether or not the required torque is increased in the motor travel mode (EV mode). If these two conditions are satisfied, the process proceeds to step S34, and either of these two conditions is satisfied. If not, the process ends.

  In step S34, it is determined whether or not the output limit value of the high-power battery 11 is equal to or greater than the threshold value. If the output limit value is equal to or greater than the threshold value, the process proceeds to step S35. The output limit value of the high-power battery 11 is set according to the temperature and SOC of the high-power battery 11.

In step S35, it is determined whether or not the output of the auxiliary equipment such as the electric air conditioner 12 and the DC / DC converter 13 can be reduced. If the output can be reduced, the process proceeds to step S36 and cannot be reduced. If so, the process ends.
In step S36, the current vehicle speed and the target vehicle speed are read, and the process proceeds to step S37.

  In step S37, permission to switch from the map to the hybrid travel mode is determined, and the process proceeds to step S38. FIG. 14 is a map used for determining permission to switch to the hybrid travel mode. For example, when the current vehicle speed is 40 [km / h] and the target vehicle speed is 50 [km / h], the travel time in the hybrid travel mode is calculated as 2 seconds. In this case, switching from the motor travel mode to the hybrid travel mode is permitted. On the other hand, when the current vehicle speed is 40 [km / h] and the target vehicle speed is 55 [km / h], the travel time in the hybrid travel mode is calculated as 5 seconds. In this case, switching from the motor travel mode to the hybrid travel mode is prohibited.

In step S38, if the switching to the hybrid travel mode is permitted in step S37, the process proceeds to step S39, and if the switching is prohibited, the process ends.
In step S39, it is determined whether or not there is no preceding vehicle. If there is no preceding vehicle, the process is terminated. If there is a preceding vehicle, the process proceeds to step S40.
In step S40, it is determined whether or not the target vehicle speed has been reached. If the target vehicle speed has been reached, the process ends. If not, the process returns to step S39.

  [Control action of hybrid vehicle]

In the fourth embodiment, permission or prohibition of switching from the motor travel mode to the hybrid travel mode is determined using the map according to the current vehicle speed and the target vehicle speed.
Since the map is used, the processing of the controller 21 can be reduced, and the processing capacity of the controller 21 can be improved.

(Other examples)
The best mode for carrying out the present invention has been described based on the first to fourth embodiments. However, the specific configuration of the present invention is not limited to the first to fourth embodiments. The present invention includes any design changes that do not depart from the spirit of the invention.

1 is a system diagram of a hybrid vehicle of Example 1. FIG. It is a figure which shows the transition locus | trajectory of the request torque with respect to the vehicle speed of Example 1. FIG. 4 is a time chart of vehicle speed and required torque in the first embodiment. 3 is a flowchart illustrating a hybrid vehicle control process in the controller according to the first embodiment. It is a graph which shows the output limit value of the high electric battery of Example 1. It is a figure which shows the transition locus | trajectory of the request torque with respect to the vehicle speed of Example 1. FIG. 4 is a time chart of vehicle speed and required torque in the first embodiment. 7 is a flowchart illustrating a hybrid vehicle control process in a controller according to a second embodiment. 4 is a time chart of vehicle speed and required torque of Example 2. 10 is a flowchart illustrating a hybrid vehicle control process in a controller according to a third embodiment. It is a figure which shows the transition locus of the request torque with respect to the vehicle speed of Example 3. FIG. 4 is a time chart of vehicle speed and required torque of Example 3. 10 is a flowchart illustrating control processing of a hybrid vehicle in a controller according to a fourth embodiment. It is a map used for judgment of permission of switching to hybrid driving mode of Example 4.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Hybrid vehicle 2 Engine 3 Drive motor 11 High power battery 12 Electric air conditioner 21 Controller 22 Vehicle speed sensor

Claims (9)

In a control device for a hybrid vehicle having an engine and a motor as a drive source of the vehicle,
Automatic traveling control means for performing automatic traveling by controlling output torque of the engine and the motor;
Mode switching means for switching between a motor travel mode driven by only the motor and a hybrid travel mode driven by the engine and the motor;
Mode transition prediction means for predicting a mode transition between the motor travel mode and the hybrid travel mode based on a current vehicle speed and a target vehicle speed;
When the mode transition predicting unit predicts that the motor traveling mode, the hybrid traveling mode, and the motor traveling mode transition in this order, the mode switching unit prohibits switching from the motor traveling mode to the hybrid traveling mode. Mode switching prohibition means,
A control apparatus for a hybrid vehicle, comprising: In the hybrid vehicle control device according to claim 1,
The automatic vehicle control means is means for determining a transition time for transition from the current vehicle speed to the target vehicle speed based on a difference between the current vehicle speed and the target vehicle speed. apparatus. In the hybrid vehicle control device according to claim 1 or 2,
The mode switching prohibiting unit permits the mode switching unit to switch from the motor traveling mode to the hybrid traveling mode when the time of the hybrid traveling mode predicted by the mode transition predicting unit is longer than a set time. A hybrid vehicle control device. The hybrid vehicle control device according to any one of claims 1 to 3,
The mode switching prohibiting means, when the time of the hybrid travel mode predicted by the mode transition predicting means is less than the set time, outputs the output of the motor above the rating during the less than the set time. A hybrid vehicle control device. In the hybrid vehicle control device according to claim 1,
The mode transition prediction means is a means for predicting a mode transition between the motor travel mode and the hybrid travel mode based on a transition of a required torque determined according to the current vehicle speed and the target vehicle speed,
When the time integral value of the required torque in the hybrid traveling mode predicted by the mode transition predicting unit is equal to or greater than a set value, the mode switching prohibiting unit determines whether the mode switching unit A hybrid vehicle control device that permits switching to a hybrid travel mode. In the hybrid vehicle control device according to any one of claims 1 to 5,
The mode switching means is means for switching from the motor travel mode to the hybrid travel mode when the output torque of the motor is equal to or greater than a set value set according to a vehicle speed,
The mode switching prohibiting means, a control apparatus for a hybrid vehicle, wherein the output torque of said motor is a means for inhibiting that the said set value or more.

In the hybrid vehicle control device according to claim 6,
The control device for a hybrid vehicle, wherein the mode switching prohibiting means increases the set value. In the hybrid vehicle control device according to claim 6 or 7,
The control device for a hybrid vehicle, wherein the mode switching prohibiting unit outputs a suppression output torque calculated by suppressing the output torque of the motor to the mode switching unit as an output torque of the motor. In the hybrid vehicle control device according to any one of claims 1 to 5,
The mode switching prohibiting means is a means having a map for determining whether switching from the motor travel mode to the hybrid travel mode is prohibited or permitted based on the current vehicle speed and the target vehicle speed. Control device.

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