JP2007186069A - Running control system for hybrid vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To further improve fuel consumption of a hybrid vehicle with a function of follow up running. <P>SOLUTION: When the hybrid vehicle is determined to be running under a follow up running condition, the speed V<SB>spdf</SB>of a preceding vehicle is acquired and compared with an engine stop preset speed V<SB>spdp</SB>, and further the V<SB>spdf</SB>+α is compared with V<SB>spdp</SB>(S10 to S18). When the V<SB>spdf</SB>is smaller than V<SB>spdp</SB>, an engine start condition is raised so as to delay engine start and a period of running by motor is increased while stopping the engine so as to improve fuel consumption (S20). When it is not determined V<SB>spdf</SB>+α is larger than V<SB>spdp</SB>, the speed V<SB>spdr</SB>of the own vehicle is set to be V<SB>spdp</SB>so as to delay engine start, and the period of running by motor while stopping the engine is increased so as to improve fuel consumption (S22). When V<SB>spdf</SB>+α is larger than V<SB>spdp</SB>, usual cruising control is carried out (S24). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an operation control system for a hybrid vehicle, and more particularly, to an operation control system for a hybrid vehicle having a follow-up running function for automatically following the running of a preceding vehicle to control the running of the host vehicle.

  When there is a traveling vehicle ahead, traveling the host vehicle in accordance with the traveling of the preceding vehicle contributes to safe driving because a certain vehicle interval can be taken, and local congestion on the road The flow of the vehicle can be made smoother, or even when a plurality of vehicles go to the destination as a group, they can be prevented from leaving other vehicles. Such a function of following the traveling of the host vehicle to the traveling of the preceding vehicle is called a following traveling function or a cruise function. When the vehicle ahead is running stably, the following vehicle that runs using the cruise function is less likely to stop or start suddenly, and travels close to constant speed. It can be performed.

  Moreover, although there exists a hybrid vehicle which mounts both an engine and a motor in a vehicle, the cruise function is mounted also about the hybrid vehicle.

  For example, Patent Document 1 discloses a vehicle speed and SOC in a vehicle having an electric motor driving mode (motor cruise mode) in which the engine is stopped when the vehicle speed is equal to or lower than a preset electric motor driving permission vehicle speed. And determining the time for motor cruise. Here, when the SOC is equal to or higher than a predetermined value, the electric vehicle travel permission vehicle speed is increased, thereby consuming the battery, whereby the SOC is decreased, and the charging mode is entered when the SOC is decreased beyond a predetermined hysteresis range. Therefore, it is stated that the SOC can be surely reduced by this hysteresis, and it is not necessary to reduce the regeneration amount for protecting the battery when the SOC is high.

  In Patent Document 2, in a hybrid vehicle equipped with both an engine and a motor, when constant speed traveling control is performed by the engine, a deceleration request is issued when a preceding vehicle is detected, and the inter-vehicle distance is set to a predetermined value. A constant-speed traveling device that shifts to control to maintain the above is described. Then, when the following control is not required because the preceding vehicle is lost, the deceleration request condition is canceled, and the constant speed traveling control is resumed, a quick acceleration can be obtained by performing torque assist by the motor for a predetermined time. It is stated.

  Patent Document 3 discloses that when a plurality of vehicles run in a coordinated manner in a platoon, control different from the case of running alone with only the own vehicle that needs to maintain the SOC always high is disclosed. . That is, it is stated that electric power is interchanged between linked vehicles so that each vehicle has a uniform SOC, and charging may be performed after the SOC has sufficiently decreased.

  In Patent Document 4, in a vehicle equipped with an automatic speed control device (adaptive cruise control) that automatically keeps at least one of the vehicle traveling speed and the inter-vehicle distance constant, during motor traveling with fuel cut, In addition, it is disclosed that the throttle opening degree is controlled by the presence or absence of automatic traveling. In other words, the crankshaft rotates along with the fuel cut and causes a pump loss, but during automatic driving, it is unlikely that rapid acceleration is required. It is stated that the response can be improved by reducing the throttle opening when the vehicle is not automatically driven.

JP 2004-23959 A JP 2000-295714 A JP 2000-308208 A JP 2004-270512 A

  As described above, hybrid vehicles having a cruise function are known, but the normal cruise function, that is, the function of following the vehicle ahead, focuses on maintaining the vehicle speed of the vehicle ahead of the vehicle ahead. Yes. In a hybrid vehicle, if the vehicle travels under certain conditions, the fuel consumption can be improved by stopping the engine and traveling with a motor. However, the conventional technology does not necessarily take into consideration the viewpoint of improving the fuel consumption.

  An object of the present invention is to provide a hybrid vehicle operation control system that can further improve fuel efficiency in a hybrid vehicle having a follow-up running function.

  The operation control system for a hybrid vehicle according to the present invention includes a follow-up running function for automatically following the running of a preceding vehicle to control the running of the host vehicle, and an engine at a speed equal to or lower than a predetermined engine stop set speed. A vehicle travel control system that travels with a motor while stopping the vehicle, the vehicle speed acquisition means for acquiring the vehicle speed of the front vehicle, which is the vehicle speed of the vehicle ahead, and a predetermined engine stop speed The comparison means for comparing the second set speed to which the extra speed is added and the forward vehicle speed, and when the forward vehicle speed is faster than the engine stop set speed and slower than the second set speed, And a fuel efficiency priority unit that prioritizes fuel efficiency improvement by setting the stop set speed.

  In the hybrid vehicle operation control system according to the present invention, the engine stop setting changing means for changing the setting of the engine stop setting speed according to whether or not the relationship between the host vehicle and the preceding vehicle satisfies a predetermined following traveling condition. It is preferable to provide.

  In the hybrid vehicle operation control system according to the present invention, the predetermined marginal speed is preferably several percent or more and ten or less percent of the engine stop set speed.

  The operation control system for a hybrid vehicle according to the present invention has a following traveling function for automatically following the traveling of the preceding vehicle and controlling the traveling of the own vehicle, and a speed equal to or lower than a predetermined engine stop set speed, When the power is equal to or lower than a predetermined engine start setting power, a hybrid vehicle operation control system having a motor travel mode in which the engine is stopped and the motor travels, and a front vehicle speed that is a vehicle speed of the front vehicle is acquired. A forward vehicle speed acquisition means, a comparison means for comparing the engine stop set speed and the forward vehicle speed, and a predetermined marginal power added to the engine start set power when the forward vehicle speed is slower than the engine stop set speed. And a fuel consumption priority unit that prioritizes the improvement of fuel consumption by raising the engine start start condition to two set powers.

  In the operation control system for a hybrid vehicle according to the present invention, it is preferable that the predetermined engine start setting power is a standard start setting power set under an arbitrary pattern running including a stop mode of the vehicle.

  In the hybrid vehicle operation control system according to the present invention, the engine stop set speed setting and the engine stop set power are changed according to whether or not the relationship between the host vehicle and the preceding vehicle satisfies a predetermined follow-up running condition. It is preferable to provide an engine stop setting changing means.

  In the operation control system for a hybrid vehicle according to the present invention, it is preferable that the predetermined margin power is not less than several percent and not more than ten percent of the engine movement setting power.

  According to at least one of the above configurations, a second set speed obtained by adding a predetermined margin speed to the engine stop set speed is provided. When the vehicle speed ahead of the vehicle is faster than the engine stop set speed and slower than the second set speed, the follow-up speed of the host vehicle is set to the engine stop set speed to give priority to improving fuel consumption. That is, in the follow-up traveling, the vehicle speed of the own vehicle is matched with the vehicle speed of the preceding vehicle, but in the vicinity of the engine stop set speed, the follow-up is stabilized to some extent and the speed of the own vehicle is often stabilized. Therefore, within a predetermined range, the vehicle speed of the host vehicle is reduced to match the vehicle speed of the preceding vehicle, and the vehicle travels with the engine stopped. As a result, the following traveling performance can be sacrificed within a range that can be quickly recovered, and the fuel consumption can be improved.

  Here, the predetermined marginal speed is set to several percent or more and ten or less percent of the engine stop set speed. For example, it is 3% or more and 10% or less. This range is preferably set according to the traveling state of the vehicle so that the following traveling performance can be recovered immediately.

  In addition, since the setting of the engine stop set speed is changed depending on whether the relationship between the own vehicle and the preceding vehicle satisfies a predetermined following traveling condition, the motor traveling mode is distinguished from the general traveling state and the following traveling state. The threshold value for shifting to can be changed, and the fuel efficiency can be further improved in the following traveling state.

  Moreover, the reference | standard of the 2nd setting power which added predetermined margin power to the engine starting setting power by at least 1 of the said structure is provided. When the vehicle speed in front of the vehicle is slower than the engine stop set speed, priority is given to improving the fuel consumption by setting the engine start setting of the own vehicle as the second set power. Here, since the engine start setting power is determined by the balance of charge / discharge of the battery, it is generally set based on a predetermined traveling mode or the like that models acceleration / deceleration of the vehicle. However, in the case of following traveling, there is not much change in acceleration / deceleration, and there is no significant change in charge / discharge of the battery. Therefore, when the set engine starting power is reached, the decision to start the engine is eased within a predetermined range, and the engine is stopped while running. Thereby, fuel consumption can be improved.

  Further, the predetermined engine start setting power is a standard start setting power set under an arbitrary pattern driving including the vehicle stop mode. Even if the second setting power is increased from the standard starting setting power, there is no significant problem in the battery balance.

  Here, the predetermined surplus power is set to several percent or more and ten or less percent of the engine movement set power. For example, it is 3% or more and 10% or less. This range is preferably set according to the running state of the vehicle so that the balance of the battery can be obtained.

  In addition, since the setting of the engine stop set speed and the engine stop set power are changed depending on whether the relationship between the own vehicle and the preceding vehicle satisfies a predetermined follow-up running condition, the normal running state and the follow-up running state are separated. Separately, the threshold value for shifting to the motor travel mode can be changed, and the fuel consumption can be further improved in the following travel state.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a configuration of an operation control system 10 for a hybrid vehicle. The hybrid vehicle operation control system 10 includes a distance sensor 14 that detects a distance between the operation control unit 12 and a preceding vehicle, a vehicle speed sensor 16 that detects the vehicle speed of the host vehicle, and an accelerator 18 that performs acceleration. Etc. are configured.

  The distance sensor 14 has a function of detecting or calculating an inter-vehicle distance between the preceding vehicle and the host vehicle. For example, the distance between vehicles can be detected by radiating radio waves or the like to the preceding vehicle and detecting the reflection. The vehicle speed of the preceding vehicle can be calculated from the time variation of the vehicle interval and the vehicle speed of the host vehicle. Alternatively, the vehicle speed of the vehicle ahead can be detected using the Doppler effect. It should be noted that the distance between vehicles can be obtained using other principles, for example, a navigation function, and the vehicle speed of the preceding vehicle can be obtained.

  The vehicle speed sensor 16 has a function of detecting or calculating the vehicle speed of the host vehicle. For example, the vehicle speed can be obtained from the rotational speed of the axle. When the vehicle is driven only by the engine, the vehicle speed can be obtained from the engine speed and the shift state.

  The accelerator 18 has a function of instructing the driver to accelerate the vehicle, and is specifically an accelerator pedal or the like. The throttle opening of the engine and the vehicle drive motor are controlled by the depression amount of the accelerator pedal, that is, the accelerator opening information. For example, when the depression amount of the accelerator pedal is large, the vehicle can be requested to accelerate rapidly, and when the accelerator pedal is released without being depressed, the vehicle can be requested not to accelerate.

  The operation control unit 12 has a function of performing overall control of the traveling of the hybrid vehicle, and is specifically a set of several vehicle element control units. For example, a vehicle controller such as a vehicle speed sensor 16, a hybrid control unit that controls an engine and a vehicle drive motor according to information such as an input unit related to vehicle driving such as an accelerator 18, and the like, and a vehicle traveling ahead according to information such as a distance sensor 14. The operation control unit 12 can be configured by a cruise control unit that follows the traveling of the host vehicle, a battery control unit that controls charging and discharging of the battery in accordance with the operation of the vehicle, and the like. Of course, these controllers may be combined into one controller or combined with a vehicle controller having other functions. The operation control unit 12 in FIG. 1 is mainly illustrated for a cruise function and a fuel efficiency improvement function.

  The operation control unit 12 includes a front vehicle distance sensor I / F 22 that is an interface between the CPU 20 and the distance sensor 14, a host vehicle speed sensor I / F 24 that is an interface with the vehicle speed sensor 16, and an accelerator opening that is an interface with the accelerator 18. Degree I / F 26, storage device 28 and the like. Each element is connected to each other by an internal bus. The operation control unit 12 can be configured by a vehicle computer or the like.

The CPU 12 _compares the following travel condition establishment determination module 30 that determines whether or not the following travel condition is satisfied, the front vehicle speed acquisition module 32 that acquires the front vehicle speed V _spdf, and V _spdf and the engine stop set vehicle speed V _spdp. The engine stop setting vehicle speed comparison module 34, the cruise control classification module 36 that classifies the cruise control method according to the comparison result, the normal cruise control module 38 that performs the normal cruise control, and the two types that give priority to fuel efficiency improvement The first fuel consumption priority cruise control module 40 and the second fuel consumption priority cruise control module 42 that perform control are included. These functions can be realized by software, specifically, by executing a corresponding cruise control program.

  The operation of the hybrid vehicle operation control system 10 having such a configuration will be described in detail with reference to the flowchart of FIG. 2 and related drawings. FIG. 2 is a flowchart showing cruise control procedures in consideration of fuel consumption in a hybrid vehicle, and these procedures correspond to the respective processing procedures of the corresponding cruise control program.

  When the hybrid vehicle is traveling, it is determined whether or not the following traveling condition is established between the vehicle, that is, the own vehicle and the preceding vehicle (S10). The following traveling condition is a condition for appropriately following the traveling of the host vehicle to the traveling of the preceding vehicle. The following traveling condition can be determined based on a criterion such as whether or not the distance between the own vehicle and the preceding vehicle, that is, whether the vehicle is closer enough to fall within a predetermined distance. The following traveling condition may consider the vehicle speeds of the host vehicle and the preceding vehicle, or may take into account the time variation of the vehicle interval. In any case, the situation relating to the traveling between the preceding vehicle and the host vehicle is acquired from various sensors of the vehicle, and compared with the setting conditions stored in advance in the storage device 28, it is determined whether the following traveling condition is satisfied. Is done. This function is executed by the follow-up running condition establishment determination module 30 of the CPU 20.

FIG. 3 is a diagram for explaining the concept of following travel. Here, the forward vehicle 52 is traveling at an inter-vehicle distance x _{n in} front of the host vehicle 50 traveling. Here, when the current inter-vehicle distance x _n is different from a predetermined inter-vehicle distance x _r determined in advance when following the forward vehicle 52 within an appropriate range, follow-up traveling is performed. For example, when x _n is longer than x _{r, the host} vehicle 50 is accelerated, the vehicle speed V _spdr of the _host vehicle 50 is increased from the vehicle speed V _{spdf of the preceding} vehicle 52, and the vehicle interval is closer to x _r . Conversely, when x _n is shorter than x _{r, the host} vehicle 50 is decelerated and the vehicle speed V _spdr of the _host vehicle 50 is lowered from the vehicle speed V _{spdf of the preceding} vehicle 52 to widen the vehicle interval and approach x _r . If x _n becomes x _r , the vehicle speed V _spdr of the _host vehicle 50 is made the same as the vehicle speed V _{spdf of the preceding} vehicle 52 and the vehicle interval is maintained at x _r . Thus, in order to maintain the vehicle spacing x _r, follow-up running to automatically follow the vehicle speed V _SPDR of the vehicle 50 to the vehicle speed V _spdf of the forward vehicle 52 are carried out.

Returning to FIG. 2, whether or not the following traveling condition is satisfied is repeatedly monitored at an appropriate sampling timing, and if it is determined that the following traveling condition is satisfied, the process proceeds to S12 and the vehicle speed V of the forward vehicle which is the vehicle speed of the preceding vehicle 52 is reached. _{Get spdf} . This function is executed by the function of the front vehicle speed acquisition module 32. In other words, the distance sensor 14 detects the inter-vehicle distance x _n between the forward vehicle 52 and the host vehicle 50 at a predetermined sampling timing via the forward person distance sensor I / F 22 and captures the data, before and after one sampling interval. obtaining a change in inter-vehicle distance x _n, and calculates the vehicle speed V _spdf of the forward vehicle 52 based on the vehicle speed V _SPDR of the vehicle 50 so as data for the next steps in. Alternatively, as described above, when there is a device for obtaining the forward vehicle speed using the Doppler effect, or when a navigation device can be used, the forward vehicle speed may be acquired from these devices.

Next, the obtained V _spdf, compared with an engine stop set vehicle speed _V spdp (S14). This function is executed by the function of the engine stop setting vehicle speed comparison module 34. Specifically, a comparison operation of V _spdf ≧ V _spdp is performed (S16), and a comparison operation of V _spdf + α> V _spdp is further performed when V _spdf ≧ V _spdp (S18). Then, according to the comparison result, the cruise control method is divided into three, and detailed fuel saving is achieved. The functions related to the classification of the cruise control method are executed by the cruise control classification module 36.

That is, in normal follow-up running, the vehicle follows the vehicle speed V _spdr = V _spdf . In the conventional hybrid vehicle, when the vehicle speed V _{spdr of the host} vehicle becomes equal to or lower than the engine stop set speed V _spdp , the engine is stopped and the vehicle is driven by the motor to save fuel consumption. The concept of following running and the concept of saving engine stop fuel consumption have been independent in the past. Here, in follow-up driving, the engine is stopped with a focus on the fact that there is less sudden stop or sudden start, stable running near the constant speed, and recovery is easy even if the followability is slightly relaxed. Increase the driving period with the motor and save fuel consumption.

First, in S16, when it is not determined that V _spdf ≧ V _spdp , that is, when V _spdf <V _spdp , the engine start start condition is raised to delay the start of the engine, and the engine runs with the motor stopped. The period to perform is increased to improve fuel consumption (S20). This function is executed by the first fuel consumption priority cruise control module 40. Here, the engine start start condition is set by power in the case of a hybrid vehicle. In the motor, the power is represented by kW, and is represented by torque × rotational speed. The engine is started when the power required by the driving condition of the vehicle is equal to or greater than a predetermined threshold value, and when the power is less than the threshold value, the motor is driven while the engine is stopped. The threshold corresponds to the engine start condition.

Conventionally, when V _spdf <V _spdp , the vehicle follows the vehicle speed V _spdr = V _spdf , but the engine is started when the power required at that time is _{equal to} or greater than a predetermined threshold. Here, the engine start setting power, which is the threshold power for starting the engine, is determined by the balance of charge and discharge of the battery, and is therefore generally set based on a predetermined traveling mode or the like that models acceleration / deceleration of the vehicle. The However, in the case of following traveling, there is not much change in acceleration / deceleration, and there is no significant change in charge / discharge of the battery. Therefore, when the set engine starting power is reached, the decision to start the engine is eased within a predetermined range, and the engine is stopped while running. Thereby, fuel consumption can be improved.

This is shown in FIG. FIG. 4 shows the vehicle speed-power relationship when the vehicle speed is plotted on the horizontal axis and the power is plotted on the vertical axis, and the accelerator opening is changed by a broken line. Here, since the vehicle speed is the vehicle speed of the _host vehicle, it is indicated by V _spdr . The engine start threshold line in the normal case is shown by a thick solid line. In FIG. 4, the engine is stopped at less than the threshold power P ₁ is at a low vehicle speed, the engine is started by P ₁ or more. When the vehicle speed is high, the engine stop set vehicle speed V _spdp is almost the boundary between engine stop and start, and the engine stops at a speed _lower than the engine stop set vehicle speed V _spdp and starts at V _spdp or higher. This engine start threshold line is an example for explanation, and various engine start threshold lines are set according to the concept of the fuel consumption design of the vehicle. In a hybrid vehicle, the engine power threshold is used to set the engine start threshold line. Start and stop boundaries can be set. The region where the engine is stopped and the vehicle is driven by the motor is a region surrounded by the engine start power threshold line, and is a region indicated by a diagonal line from the upper left to the lower right in FIG.

As described above, in the case of following traveling, there is not much change in acceleration / deceleration, and there is no significant change in charge / discharge of the battery. Therefore, the decision to start the engine can be relaxed within a predetermined range when the engine starting set power is reached. In FIG. 4, a relaxed engine start power threshold line is shown by a thin solid line. Here, it is shown as a _second power P ₂ having a margin more than the power P ₁ at a low speed, and is shown almost overlapping with a conventional threshold line at a high speed. Therefore, the area surrounded by the engine start power threshold line, that is, the area where the engine is stopped and the motor is driven is expanded. In FIG. 4, the area shown by crossing the diagonal line from the upper left to the lower right and the diagonal line from the upper right to the lower left is an enlarged area. Increases fuel efficiency.

That is, a reference of the second set power obtained by adding a predetermined margin power to the engine start set power is provided, and when the vehicle speed of the front vehicle is slower than the engine stop set speed, the engine start setting of the own vehicle is set as the second set power. Priority can be given to improving fuel economy. The marginal power, for example, the difference between P ₂ and P ₁ in FIG. 4 is set to be several percent or more and tens of percent or less of the engine start setting power P ₁ . For example, it can be 3% or more and 10% or less. More preferably, the surplus power is preferably about 5% of the engine start setting power. If it is about this level, it is possible to improve the fuel efficiency without greatly affecting the balance of the battery and reducing the deterioration of the followability. In addition, these depend on the output performance of the battery.

Returning to FIG. 2 again, as a second improvement in fuel consumption, if it is not determined in S18 that V _spdf + α> V _spdp , the vehicle speed V _spdr of the _host vehicle is set to V _spdp , the engine start start is delayed, and the engine is started. The period during which the vehicle runs with the motor stopped is increased to improve fuel efficiency (S22). This function is executed by the second fuel consumption priority cruise control module 42. Conventionally, when V _spdf ≧ V _spdp , the vehicle follows the vehicle speed V _spdr = V _spdf , and the speed is _higher than the engine stop set vehicle speed V _spdp , so the engine is started. However, the follow-up traveling is to match the vehicle speed of the own vehicle with the vehicle speed of the preceding vehicle, but in the vicinity of the engine stop set speed, the follow-up is stabilized to some extent and the speed of the own vehicle is often stabilized. Therefore, within a predetermined range, the vehicle speed of the own vehicle is adjusted to the vehicle speed of the preceding vehicle, and the vehicle travels with the engine stopped. Thereby, fuel consumption can be improved.

This is shown in FIG. In FIG. 5, the horizontal axis represents the vehicle speed V _{spdf of the preceding} vehicle, the vertical axis represents the vehicle speed V _spdr of the own vehicle, and the change in the vehicle speed V _spdr of the own vehicle in the case of following traveling is shown by a thick solid line. In FIG. 5, when the vehicle speed V _{spdf of the preceding} vehicle is _lower than the normal engine stop set speed V _spdp , the vehicle follows V _spdr = V _{spdf and} the vehicle speed V _{spdf of the preceding} vehicle is V ₂ = V _spdp. It is shown that V _spdr = V _spdf follows even at a speed higher than + α. In other words, the _host vehicle follows the vehicle at the same vehicle speed as that of the _preceding vehicle, except for a region where V _spdf is V _spdp or more and less than V _spdp + α. Then, in the region of less than V _spdf is V _SPDP or V _SPDP + alpha, vehicle speed V _SPDR of the vehicle is fixed to the left engine stop set vehicle speed V _SPDP, it does not follow the vehicle speed V _spdf of the forward vehicle.

That is, in a _region where V _{spdf is} greater than or _equal to V _{spdp and} less than V _spdp + α, the engine is stopped and the vehicle is driven by the motor without following the vehicle speed V _spdf of the _preceding vehicle, and priority is given to fuel efficiency improvement. In FIG. 5, the engine stop region is indicated by two types of hatched regions. One is a _region where the vehicle speed V _{spdf of the preceding} vehicle is lower than the normal engine stop set speed V _spdp , and this region is indicated by a diagonal line from the upper left to the lower right. The other is a _region where V _spdf is V _spdp or more and less than V _spdp + α, and is indicated by a region where the diagonal line extending from the upper left to the lower right and the diagonal line extending from the upper right to the lower left are intersected. The latter area is an enlarged portion of the area where the engine is stopped and the vehicle is driven by the motor, and the period during which the engine is stopped and the vehicle is driven is increased by this increased amount, thereby improving fuel efficiency.

That is, a second set speed obtained by adding a predetermined margin speed to the engine stop set speed is provided. When the vehicle speed ahead of the vehicle is faster than the engine stop set speed and slower than the second set speed, the follow-up speed of the host vehicle can be set to the engine stop set speed to give priority to fuel efficiency improvement. The difference between the second set speed and the engine stop set speed is a surplus speed, for example, the difference between V ₂ and V _spdp in FIG. 5. This surplus speed is several percent or more than a dozen of the engine stop set speed V _spdp. % Or less. For example, it can be 3% or more and 10% or less. More preferably, the engine stop set speed V _spdp is about 5%. This range is preferably set according to the traveling state of the vehicle so that the following traveling performance can be recovered immediately.

When it is determined in S18 that V _spdf + α> V _spdp , the normal cruise control described with reference to FIG. 3 is performed (S24), and generally the vehicle speed V _{spdr of the host} vehicle _. = _Tracking is performed as the vehicle speed V _spdf of the vehicle ahead. This function is usually performed by the cruise control module 38. Here, the fuel efficiency improvement is performed according to the engine stop set vehicle speed V _{spdp, the} engine start set power P _{1, and the} like.

In the above description, the engine stop set vehicle speed V _spdp and the engine start threshold power P _{1, which} are threshold _values for stopping the engine and shifting to the motor travel mode, are those set during normal travel. The threshold value for shifting to the motor traveling mode may be changed depending on whether the traveling state satisfies the following traveling condition. That is, under the following traveling condition, the threshold value for shifting to the motor traveling condition can be increased to further improve the fuel consumption.

It is a figure which shows the structure of the operation control system of the hybrid vehicle in embodiment which concerns on this invention. 5 is a flowchart illustrating a cruise control procedure in consideration of fuel consumption in the embodiment according to the present invention. It is a figure explaining the concept of follow running. In embodiment which concerns on this invention, it is a figure explaining a mode that engine start setting power is eased. In embodiment which concerns on this invention, it is a figure explaining a mode that an engine stop set speed is eased.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Hybrid vehicle operation control system, 12 Operation control part, 14 Distance sensor, 16 Vehicle speed sensor, 18 Accelerator, 20 CPU, 22 Front vehicle distance sensor I / F, 24 Own vehicle vehicle speed sensor I / F, 26 Accelerator opening I / F, 28 storage device, 30 following travel condition establishment determination module, 32 forward vehicle speed acquisition module, 34 engine stop setting vehicle speed comparison module, 36 cruise control classification module, 38 normal cruise control module, 40 first fuel consumption priority cruise control module , 42 Second fuel consumption priority cruise control module, 50 own vehicle, 52 forward vehicle.

Claims (7)

A follow-up running function that automatically follows the running of the vehicle ahead and controls the running of the vehicle,
When the speed is equal to or lower than a predetermined engine stop set speed, a motor travel mode in which the engine is stopped and the motor travels,
An operation control system for a hybrid vehicle having
Forward vehicle speed acquisition means for acquiring a forward vehicle speed that is the vehicle speed of the forward vehicle;
A comparison means for comparing the second set speed obtained by adding a predetermined margin speed to the engine stop set speed and the vehicle speed in front of the vehicle;
A fuel efficiency priority unit that prioritizes fuel efficiency improvement by setting the following speed of the vehicle to the engine stop setting speed when the vehicle speed ahead of the vehicle is faster than the engine stop setting speed and slower than the second setting speed;
An operation control system for a hybrid vehicle, comprising: In the operation control system of the hybrid vehicle according to claim 1,
An operation control system for a hybrid vehicle, comprising engine stop setting change means for changing a setting of an engine stop set speed according to whether or not a relationship between the own vehicle and a preceding vehicle satisfies a predetermined following traveling condition. In the operation control system of the hybrid vehicle according to claim 1,
The hybrid vehicle operation control system is characterized in that the predetermined marginal speed is not less than several percent and not more than ten percent of the engine stop set speed. A follow-up running function that automatically follows the running of the vehicle ahead and controls the running of the vehicle,
A motor travel mode in which the engine is stopped and travels with a motor when the speed is equal to or lower than a predetermined engine stop set speed and equal to or lower than a predetermined engine start set power;
An operation control system for a hybrid vehicle having
Forward vehicle speed acquisition means for acquiring a forward vehicle speed that is the vehicle speed of the forward vehicle;
A comparison means for comparing the engine stop set speed and the vehicle speed ahead,
A fuel efficiency priority unit that prioritizes fuel efficiency improvement by raising the engine start start condition to a second set power obtained by adding a predetermined marginal power to the engine start setting power when the vehicle speed ahead is slower than the engine stop set speed;
An operation control system for a hybrid vehicle, comprising: In the hybrid vehicle operation control system according to claim 4,
The predetermined engine start setting power is a standard start setting power set under an arbitrary pattern running including a stop mode of the vehicle. In the hybrid vehicle operation control system according to claim 4,
A hybrid vehicle comprising engine stop setting change means for changing the setting of the engine stop set speed and the engine stop set power according to whether or not the relationship between the host vehicle and the preceding vehicle satisfies a predetermined follow-up running condition Navigation control system. In the hybrid vehicle operation control system according to claim 4,
The hybrid vehicle operation control system is characterized in that the predetermined margin power is not less than several percent and not more than ten percent of the engine start setting power.

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