JP2000052818A - Driving force controller for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform aimed control without rapidly varying of engine output even if a large response delay exists in either one of engine control or speed change control when driving force is excessively controlled by the engine control and the speed change control. SOLUTION: Demand driving force Ts is found out from an accelerator pedal step-down amount APS and car speed VSP in a demand axle driving force computing unit 21, excessively target driving force TST is found out in a target engine output computing unit 26, and demand horsepower HPs is found out by multiplication of the excessively target driving force TST and axle revolution speed Ns in a demand horsepower computing unit 23. In a transmission target input revolution speed computing unit 24, transmission target input revolution speed Npri* corresponding to engine revolution speed generated the request horsepower HPs by minimum fuel consumption based on an engine characteristic diagram is found out to calculate a transmission gear ratio i*. Target engine output computing unit Te* is found out by dividing the excessively target driving force TST in a wheel driving system actual transmission gear ratio iT in a target engine output computing unit 28, a corrected target engine output TeT is found out by adjusting a correct amount involved to the target engine output computing unit Teu* for counterbalancing a large delay value of a response delay so as to prevent generation of rapidly varying of engine output in a speed change delay value correct adjustment unit 29, and a target throttle opening TVO* for generating the corrected target engine output TeT is found out in a speed change delay value correctly computing unit 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving force control apparatus for appropriately determining a required wheel driving force of a vehicle equipped with a continuously variable transmission under transient control as a combination of an engine output and a gear ratio. More particularly, the present invention relates to a driving force control device for a vehicle that is useful when there is a difference in response delay between control systems for achieving the engine output and the gear ratio.

[0002]

2. Description of the Related Art A continuously variable transmission represented by a V-belt type continuously variable transmission or a toroidal type continuously variable transmission generally determines a target gear ratio from an engine required load and a vehicle speed. Shift control is performed to achieve the target gear ratio. Therefore, during acceleration in which the driver depresses the accelerator pedal to increase the required engine load, the target gear ratio is changed to be larger (to be a lower speed gear ratio), and the continuously variable transmission is set to the increased target gear ratio. When the vehicle is downshifted to the gear ratio, and conversely, during a low-load operation in which the driver returns the accelerator pedal to reduce the required engine load, the target gear ratio is changed to be smaller (to be a higher gear ratio). The continuously variable transmission is upshifted to the reduced target gear ratio.

On the other hand, as a technique for obtaining a required driving force of a vehicle, there is a technique described in, for example, JP-A-7-172217. This technology calculates the target driving force of the vehicle from the vehicle speed and the amount of accelerator pedal depression,
The required driving force to be transmitted to the wheels is added to the running resistance that can be estimated from the vehicle speed.

[0004] By the way, in the above-mentioned conventional speed change control of a continuously variable transmission, the required driving force obtained by the technique disclosed in the above-mentioned literature cannot be accurately realized. In any case, it is impossible to realize the required driving force in such a manner that the fuel efficiency of the engine is minimized.

For example, in order to achieve the required driving force in such a manner that the fuel efficiency of the engine is minimized, the required driving force is controlled by controlling the output of the engine and the shift control of the continuously variable transmission (the engine speed). Control) that can be realized by an appropriate combination with (control). The required driving force is a stationary target value, and a transient target value is determined in order to achieve this with a predetermined change over time and obtain a suitable acceleration / deceleration feeling. It is better to achieve the force target value every moment.

[0006] As a driving force control system for that purpose,
For example, the one shown in FIGS.
The driving force control system in FIG. 10 is based on the vehicle speed VSP and the accelerator pedal depression amount APS in the requested axle driving force calculation unit 121.
For example, the required minimum axle driving force T _S according to the driving state and running conditions of the vehicle is obtained by the method described in the above-mentioned Japanese Patent Application Laid-Open No. 7-172217. The force T _S is passed through a filter corresponding to a predetermined required driving force transient characteristic, and an instantaneous transient target axle driving force T _ST for realizing the required axle driving force T _S with a predetermined change over time is calculated.

On the other hand, the axle rotation speed calculation unit 122 obtains the current axle rotation speed N _S by dividing the transmission output rotation speed N _sec by the final drive gear ratio i _F. The request horsepower calculation unit 123 calculates a required horsepower HP _S by multiplying the transitional target axle drive force T _ST and the axle rotation speed N _S. The transmission target input speed calculation unit 124 calculates the required horsepower HP based on the characteristic diagram of the engine obtained in advance through experiments or the like.
A target engine speed for generating _S (transient target axle driving force T _ST ) with minimum fuel consumption is determined, and a transmission target input speed N _pri ^* corresponding to the target engine speed is determined.
5 controls the speed of the continuously variable transmission such that the target input rotation speed _Npri ^* is achieved.

[0008] wheel drive system actual transmission ratio calculating section 127, transmission input rotational speed N _pri the axle rotation speed N _S (= N _sec
/ I _F ) to obtain the actual gear ratio i _T of the wheel drive system.
The target engine output calculating unit 128 divides the transient target axle driving force T _ST obtained as described above by the transient target axle driving force calculating unit 126 by the wheel drive system actual gear ratio i _T to obtain a transient. A target engine output (torque) T _e ^* for realizing the target axle driving force T _ST with minimum fuel consumption is obtained. The target engine output _Te ^* from the calculation unit 128 is input to the engine output control unit 130, and the calculation unit 13
0 controls the engine such that the target engine output _Te ^* is generated.

For this reason, the transient target axle driving force T _ST for achieving the required axle driving force T _S with the transient characteristics determined in the calculation unit 126 is generated in such a manner that the (required horsepower HP _S ) is generated with minimum fuel consumption. Shift control of the continuously variable transmission and output control of the engine can be performed.

The driving force control system of FIG. 11 obtains the target engine output _Te ^{* in the same} manner as described above, but obtains the transmission target input rotational speed _Npri ^* as described above. Without converting the force T _ST into the required horsepower HP _S , the transmission target input speed calculation unit 133 uses the transient target axle driving force T _ST and the vehicle speed VSP based on the data map obtained based on the engine characteristic diagram. The target engine speed for generating the transient target axle driving force _TST with minimum fuel consumption is obtained based on the vehicle speed VSP, and the transmission target input speed _Npri ^* corresponding thereto is obtained.

The driving force control system shown in FIG. 12 is provided with a transmission target input speed / target engine output calculator 147 instead of the transmission target input speed calculator 24 in FIG. When calculating the minimum fuel consumption engine speed (transmission target input speed _Npri ^* ) based on the map corresponding to the performance diagram, the target engine output _Te ^* is also obtained from the same map at the same time. This is supplied to the shift control unit 125 and the engine output control unit 130.

The driving force control system shown in FIG.
Transmission target input rotation speed N to section 125_pri ^*In FIG.
, But the target engine output T_e ^*Less than
It is made to ask as follows. That is,
The above-described transmission target is calculated by the wheel drive system target gear ratio calculation unit 145.
Input speed N _pri ^*Is the axle rotation speed N_SDivide by
As a result, the wheel drive system target speed ratio i_T ^*And calculate the goal
In the engine output calculation unit 128, from the calculation unit 126
Target axle driving force T_STIs the target gear ratio i of the wheel drive system._T
^*, The transient target axle driving force T_STThe most
Target engine output T to achieve low fuel consumption_e ^*Calculate
Then, this is supplied to the engine output control unit 130.

[0013]

However, in the case where the target axle driving force is to be transiently controlled, the output control of the engine and the continuously variable transmission are required in any of the driving force control devices shown in FIGS. It has been confirmed that if there is a large difference in response delay from the speed change control, the following problem will occur. The problem will be described below in the case where the shift control of the continuously variable transmission has a larger response delay than the output control of the engine, as is usually the case.

Driving force control device shown in FIGS. 10 and 11
, The target engine output T_e ^*When asking for
Wheel drive system actual gear ratio i, which is the actual gear ratio_TUsing
Therefore, the target engine output T_e ^*Shift response to the calculation of
The delay has already been taken into account. In other words, the goal
Engine power T_e ^*Is the transient target axle due to shift response delay
Driving force T _STHas been increased or decreased to compensate for the delay in
Transient target axle driving force T despite shift response delay_STIs
It can be realized one by one.

However, if the response delay of the shift control is significantly greater than that of the engine output control, the required axle driving force T _S , and thus the transient target axle driving force T _ST , suddenly increases due to a sudden increase in accelerator pedal depression. In addition, a large delay of the shift response is added to this, and the transient target axle driving force T _ST is faithfully realized. I can't completely eliminate the concerns of worsening sex.

In order to solve this problem, in a general method of adjusting the transient characteristics of the transient target axle driving force calculating unit 126 so as not to cause a sudden increase in the engine output, which is a problem, the adjustment is performed by a shift control. The system also delays the change in the transmission target input speed N _pri ^* , and if it is attempted to prevent the deterioration of drivability, it becomes impossible to correct the response delay of the speed change control. It cannot be a solution.

Further, as in the driving force control device shown in FIG.
Target transient axle driving force T_STAnd axle speed N_STo multiply with
Required horsepower HP_SDirectly from the target engine
Force T _e ^*Or the driving force control device shown in FIG.
, The transmission target input rotation speed N_pri ^*The axle speed
N_STarget gear ratio i obtained by dividing by_T ^*By
Transient target axle driving force T_STIs divided by
Engine output T_e ^*1 and FIG. 1 and FIG.
Unlike the case of 1, the target engine output T_e ^*To ask
At this time, the actual gear ratio i of the wheel drive system, which is the actual gear ratio,_TFor
The target engine output T_e ^*Shift to the calculation of
The response delay is not taken into account.

For this reason, the realization of the transient target axle driving force T _ST is delayed by the shift response delay, and it is difficult even to realize the transient target axle driving force T _ST . Techniques for compensating for this shift response delay have been conventionally considered,
Even if the transient target axle driving force T _ST is faithfully realized by the countermeasure, even if the response delay of the shift control is significantly larger than that of the engine output control, the above-mentioned concern, that is, a sudden increase in the accelerator pedal depression amount, etc. When the transient target axle driving force T _{ST suddenly} increases, it is not possible to eliminate the concern that the driving performance is deteriorated due to the torsional resonance of the vehicle body and the drive system due to the sudden increase in the engine output.

In view of the above situation, a first aspect of the present invention provides a method for transiently controlling a target driving force.
Even when there is a difference in response delay between the engine output control and the shift control, the driving force deviation caused by the response delay of the control system having a large response delay is reduced so that the above transient control is faithfully realized. Reducing the sudden change of the engine output at the time of sudden change of the target driving force, which is a problem when offsetting by the control amount of the control system, alleviates the torsional resonance of the vehicle body and the drive system due to the sudden change of the engine output and deteriorates drivability It is an object of the present invention to eliminate the above-mentioned concerns and to propose a driving force control device for a vehicle which has solved the above-mentioned problems.

According to a second aspect of the present invention, the object of the first aspect is achieved when the engine is assisted by an auxiliary power source and when the response delay of the shift control system is larger. It is an object of the present invention to propose a driving force control device for a vehicle.

According to a third aspect of the present invention, when the response delay of the shift control system is large and the control amount of the engine output control system and / or the auxiliary power control system is corrected, it is caused by the response delay of the shift control system. It is an object of the present invention to propose a driving force control device for a vehicle capable of suitably canceling the axle driving force deviation.

According to a fourth aspect of the present invention, when the response delay of the shift control system is large and the control amount of the engine output control system and / or the auxiliary power control system is corrected, the response delay of the shift control system is caused. It is an object of the present invention to propose a different type of driving force control device capable of suitably offsetting the axle driving force deviation.

[0023]

For these purposes, a vehicle driving force control apparatus according to a first aspect of the present invention comprises an engine capable of arbitrarily changing the output by factors other than the operation of an accelerator pedal, and a continuously variable transmission. A vehicle equipped with a power train that is a combination of the target engine speed and the target engine output for realizing the transient target axle driving force determined from the required axle driving force determined by the driving state and running conditions of the vehicle. A combination is determined, the speed of the continuously variable transmission is controlled so as to be a transmission target input speed corresponding to the target engine speed, and the output of the engine is controlled to be the target engine output. Of the output control, the control target value of the smaller response delay is determined by the axle driving force deviation caused by the response delay of the larger response delay. In the driving force control apparatus for a vehicle, the correction amount for offsetting the deviation of the axle driving force deviation with respect to the control target value of the smaller response delay is determined by the required axle driving force and the transient target axle. Independently of the driving force, the adjustment is made such that the sudden change of the control target value with the smaller response delay is suppressed.

A driving force control device for a vehicle according to a second aspect of the present invention
In the first invention, the engine is assisted by an auxiliary power source, and the output of each of the engine and the auxiliary power source is individually controlled so that the total output becomes the target engine output. The output control of the auxiliary power source and the output control of the engine and the auxiliary power source output control system so that the axle driving force deviation caused by the response delay of the shift control having the largest response delay among the shift control is offset. In the case where the control target value is corrected, the correction amount for offsetting the axle driving force deviation with respect to the control target values of the engine output control system and the auxiliary power source output control system is individually determined. The present invention is characterized in that an adjustment is made so as to suppress a sudden change in the total.

A driving force control device for a vehicle according to a third aspect of the present invention
In the first invention or the second invention, among the output control of the engine and / or the output control of the auxiliary power source, and the shift control, the axle driving force deviation caused by the response delay of the shift control having the largest response delay is determined. When correcting the control target values of the engine output control system and / or the auxiliary power source output control system so as to cancel each other, the target engine output is obtained by dividing the transient target axle driving force by the actual gear ratio. The target engine output is configured to be the one that has been corrected by itself.

A vehicle driving force control apparatus according to a fourth aspect of the present invention
In the first invention or the second invention, among the output control of the engine and / or the output control of the auxiliary power source, and the shift control, the axle driving force deviation caused by the response delay of the shift control having the largest response delay is determined. When correcting the control target values of the engine output control system and / or the auxiliary power source output control system so as to cancel each other, the target engine output is determined based on the required horsepower corresponding to the transient target axle driving force, Alternatively, the target engine output is calculated by dividing the transient target axle driving force by a target gear ratio calculated from the transient target axle driving force, and the target engine output is calculated by calculating an axle driving force deviation caused by a response delay of the shift control. The correction is made so that the minutes are canceled.

[0027]

According to the first aspect of the present invention, a combination of a target engine speed and a target engine output for realizing a transient target axle driving force obtained from a required axle driving force determined by a driving state and running conditions of a vehicle is obtained. Driving force control is performed to control the speed of the continuously variable transmission so as to attain the transmission target input speed corresponding to the target engine speed and to control the output of the engine so as to attain the target engine output. The output from the engine controlled as described above is shifted by the continuously variable transmission controlled to shift as described above and becomes the output of the power train.

[0028] Of the above-mentioned shift control and engine output control, the control target value of the smaller response delay is corrected so that the axle driving force deviation caused by the response delay of the larger response delay is canceled. From this, the axle driving force deviation caused by a large response delay can be offset by correcting the control target value of the smaller response delay, and the transient target axle driving force can be faithfully reproduced without being affected by the large response delay. Can be realized.

In the first invention, in particular, the correction amount for offsetting the deviation of the axle driving force deviation with respect to the control target value having the smaller response delay is separately set from the required axle driving force and the transient target axle driving force. However, since the adjustment is made such that the sudden change of the control target value of the smaller response delay is suppressed, when the larger response delay becomes significantly larger than the smaller response delay, the request is made due to a sudden increase in the accelerator pedal depression amount or the like. Even when the axle driving force, and thus the transient target axle driving force, suddenly increases, the engine output does not increase so much as to cause a problem, and the transient target axle driving force is faithfully realized by correcting the control target value. However, there is a concern that driving performance will deteriorate due to a sudden increase in engine output under driving conditions where the transient target axle driving force suddenly increases, causing torsional resonance of the vehicle body and drive system. It is possible to wipe.

In the second invention, the above-mentioned engine is assisted by an auxiliary power source, and the output of each of the engine and the auxiliary power source is individually controlled so that the total output becomes the target engine output. An engine output control system and an auxiliary power source such that an axle driving force deviation caused by a response delay of a shift control having the largest response delay among the output control of the engine, the output control of the auxiliary power source, and the shift control is cancelled. When the control target value of the output control system is corrected, the correction amount for offsetting the axle driving force deviation from the control target value of the engine output control system and the control target value of the auxiliary power source output control system is individually determined. Adjustments are made so that sudden changes in the total of the control target values are suppressed, so in vehicles that are also driven by power from an auxiliary power source such as an electric motor, and In the case towards the response delay of the control system is large, it is possible to achieve the first invention and similar purposes.

In the third invention, the output control of the engine and / or the output of the auxiliary power source according to the first invention or the second invention and the response control of the shift control having the largest response delay among the shift controls are performed. When correcting the control target value of the engine output control system and / or the output control system of the auxiliary power source so as to cancel the deviation of the axle driving force caused by the axle driving force deviation, the transient target axle driving force is divided by the actual gear ratio to obtain the target value. By obtaining the engine output, the target engine output itself is the one that has been subjected to the above-described correction, so that no special means for the correction is required, and the axle drive is reliably performed. The offset of the force deviation can be realized, and both low cost and accuracy can be achieved, which is very advantageous.

In the fourth invention, the output control of the engine and / or the output of the auxiliary power source according to the first invention or the second invention, and the response control of the shift control having the largest response delay among the shift controls are performed. When correcting the control target value of the engine output control system and / or the auxiliary power source output control system so that the resulting axle driving force deviation is offset, the aforementioned required horsepower corresponding to the transient target axle driving force is corrected. The target engine output is calculated, or the target engine output is calculated by dividing the transient target axle driving force by the target gear ratio obtained from the transient target axle driving force, and the target engine output is calculated as a response delay of the shift control. Since the axle driving force deviation caused by the correction is corrected so as to be offset, a means for the correction is required, but the above-described method is surely performed by a model different from the third invention. Advantageously able to realize the axial driving force deviations of offset.

[0033]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a power train of a vehicle provided with a driving force control device according to an embodiment of the present invention and a control system thereof, and the power train includes an engine 1 and a continuously variable transmission 2. The engine 1 is composed of an internal combustion engine, but is not linked to an accelerator pedal 3 operated by a driver, but is separated from the accelerator pedal 3 and has a throttle valve 5 whose opening is electronically controlled by a step motor 4. Set the motor 4 to the target throttle opening (T
By setting the rotational position in accordance with the VO ^* ) command, the throttle valve 5 is set to the target throttle opening TVO ^* , so that the output of the engine 1 can be controlled by factors other than the operation of the accelerator pedal.

The continuously variable transmission 2 is a well-known V-belt type continuously variable transmission, and includes a primary pulley 7 which is drivingly connected to an output shaft of the engine 1 via a torque converter 6 and a secondary pulley 8 which is aligned with the primary pulley 7. And a V-belt 9 stretched between these pulleys. Then, a differential gear device 11 is drive-coupled to the secondary pulley 8 via a final drive gear set 10, and the wheels (not shown) are rotationally driven by these.

In order to shift the continuously variable transmission 2, one of the flanges forming the V-grooves of the primary pulley 7 and the secondary pulley 8 is relatively moved closer to the other fixed flange. or narrow the V groove width Te, so as to be spread V groove width was separated, the two movable flanges, the target gear ratio (i ^*) primary pulley pressure from the hydraulic actuator 12 which operates in response to the command P _pri and secondary pulley pressure by displacing to a position corresponding to P _sec, and as it can be continuously variable to the continuously variable transmission 2 we are the actual gear ratio matches the target gear ratio i ^*.

The target throttle opening TVO ^* and the target gear ratio i ^* are calculated and obtained by the controller 13. Because of this, the controller 13
Depressed position of accelerator pedal 3 (accelerator depression amount) AP
And a throttle opening sensor 1 for detecting the throttle opening TVO.
6, a signal from a primary pulley rotation sensor 17 for detecting the rotation speed (primary rotation speed) _Npri of the primary pulley 7, and a secondary pulley for detecting the rotation speed (secondary rotation speed) _Nsec of the secondary pulley 8. A signal from the rotation sensor 18 and a signal from a vehicle speed sensor 19 for detecting a vehicle speed VSP are input.

Based on the input information, the controller 13 performs the shift control of the continuously variable transmission 2 and the throttle opening degree control of the engine 1 as shown in the functional block diagram of FIG. The driving force control of the vehicle targeted by the invention is executed. The driving force control device shown in FIG.
No. 0 is obtained by adding an improvement according to the present invention. In the required axle driving force calculation unit 21, for example, based on the accelerator pedal depression amount APS detected by the sensor 14 and the vehicle speed VSP detected by the sensor 19, for example, the aforementioned Japanese Patent Laid-Open No. 7-172
No. 217, the required minimum axle driving force T according to the driving state and running conditions of the vehicle.
_Ask for _S.

[0038] In transitional target axle drive force computing section 26, through the required axle driving force T _S to filter corresponding to a predetermined transient characteristic, sometimes for realizing the request transaxle force T _S at a predetermined temporal change An instantaneous transient target axle driving force T _ST is calculated.

On the other hand, the axle rotation speed calculating section 22 is provided with the sensor 1
8, the secondary rotation speed N detected_secThat is, shifting
Machine output rotation speed, the gear of final drive gear set 10
Ratio (final drive gear ratio) i_FTo divide by
Therefore, the current axle rotation speed N _SAsk for. And request horse
The force calculation unit 23 calculates the transient target obtained as described above.
Axle driving force T_STAnd axle speed N_SRequest horse by multiplication with
Power HP_SIs calculated.

The transmission target input speed calculating section 24 calculates the required horsepower HP _S (transient target axle driving force T _ST ) based on the engine characteristic diagram shown in FIG. the seek ^* target value N _e of the engine speed N _e for generating a minimum fuel consumption, then the target engine speed N _e transmission target input rotation speed corresponding to the ^* (target primary rotation speed) N _pri ^* Ask.

[0041] Here FIG. 7, the engine speed N _e, the relationship between the engine output (torque) T _e, as iso-fuel consumption lines α fuel consumption rate becomes the same, also, like the output horsepower becomes the same The minimum fuel consumption line connecting points at which the fuel consumption rate is the best on each isohorsepower line β is indicated by δ. In the FIG. 7, the intersection of one and the equal horsepower line β and minimum fuel consumption line δ of corresponding to the request horsepower HP _S is assumed to be Z point in FIG. 7, for example, to generate the request horsepower HP _S Lowest mileage Target engine speed N for
_e ^* can be obtained as a scale value lowered from the point Z to the horizontal axis as shown in FIG.

In the vehicle equipped with a continuously variable transmission, the torque converter 6 is in a lock-up state in which the input and output elements are directly connected for most of the time during power transmission. and the handling of input rotational speed N _pri ^* for convenience equal to the target engine speed N _e ^*.

The transmission target input rotation speed N _pri ^* is input to a target transmission ratio calculation unit 25, and the calculation unit 25 divides the transmission target input rotation speed N _pri ^* by the transmission output rotation speed N _sec . As a result, the target speed ratio i ^* corresponding to the transmission target input speed N _pri ^* is obtained and output to the hydraulic actuator 12 as shown in FIG.
^* , That is, the speed change control is performed so that the target input rotation speed _Npri ^* is achieved.

[0044] In the wheel drive system actual transmission ratio calculator 27, a wheel drive system the actual speed by dividing the primary pulley rotational speed detected by the sensor 17 (transmission input rotational speed) N _pri in the axle rotation speed N _S The ratio i _T is calculated, and the target engine output calculation unit 28 divides the transient target axle driving force T _ST obtained as described above in the transient target axle driving force calculation unit 26 by the actual wheel drive system gear ratio i _T. As a result, a target engine output (torque) _Te ^* for realizing the transient target axle driving force _TST with minimum fuel consumption is obtained. Here, the target engine output (torque) T _e ^* is a value corresponding to the torque scale value indicated by the line drawn downward from the point Z to the vertical axis in FIG.

By the way, the target engine output T_e ^*Ask for
In this case, the actual change of the wheel drive system
Speed ratio i_T, The target engine output T_e
^*The shift response delay is already taken into account in the calculation of
Become. That is, the target engine output T_e ^*Is a shift response delay
Target axle driving force T due to _STTo compensate for the delay
The transient
Mark axle driving force T_STCan be realized faithfully. Note that
The response delay of the gin output control is
Much smaller, response target of engine output control is a transient target
Axle driving force T_STRarely hinders the faithful realization of
No.

Here, the faithful realization of the transient target axle driving force T _ST is such that when the response delay of the shift control is significantly larger than the response delay of the engine output control, the required axle driving force T _S is increased due to a sudden increase in accelerator pedal depression. Therefore, when the transient target axle driving force T _{ST suddenly} increases, a large shift response delay is added to the transient target axle driving force T _ST , causing a sudden increase in the engine output,
Drivability may be deteriorated due to torsional resonance of the vehicle body or the drive system.

[0047] directly without using the engine output control, the target engine output T _e ^* a transmission delay of the correction amount before it the target engine output T _e ^* from particular, computing unit 28 in the present embodiment for solving this problem The correction amount is input to the adjustment unit 29, and as described above, the shift control response delay (for canceling) correction amount included in the target engine output _Te ^* is converted into an engine output that causes a problem with the target engine output _Te ^* . The corrected target engine output _TeT is adjusted so as not to cause a sudden increase.

The corrected target engine output _TeT obtained as described above is input to the target throttle opening calculating section 30, which calculates the corrected target engine output TT.
A target throttle opening TVO ^{* at} which _eT occurs is obtained and output to the step motor 4 as shown in FIG. 1, and the opening of the throttle valve 5 is controlled to the target throttle opening TVO ^* .

According to the present embodiment as described above, the transient target axle driving force T _ST for achieving the required axle driving force T _S with the transient characteristics determined by the calculation unit 26 is generated with minimum fuel consumption. In this manner, the shift control (i ^* ) of the continuously variable transmission and the throttle opening control (TVO ^* ) of the engine can be performed. And this time, in order to determine the actual gear ratio at which wheel driveline actual gear ratio i _T with a target engine output T _e ^*, this target engine output T _e ^* itself, response than the engine output control already become those considering the response delay of the larger shift control delay, i.e. the target engine output T _e ^* if, is increased or decreased corrected to compensate for changes in delay of the transient target axle drive force T _ST by the shift response delay become things, by the throttle opening control (engine output control) and shift control based on the target speed ratio i ^* based on this, it is minutely faithfully realize the transient target axle drive force T _ST despite shift response delay of the Can be.

For this reason, when the response delay of the shift control is significantly larger than the response delay of the engine output control, the required axle driving force T _S , and thus the transient target axle driving force T _ST , increases rapidly due to a sudden increase in accelerator pedal depression. At this time, the delay of the shift response was added to this, which caused a sudden increase in the engine output, and the drivability deteriorated due to torsional resonance of the vehicle body and drive system. In the embodiment, in particular, the target engine output _Te ^* from the arithmetic unit 28 is not used as it is for the engine output control. In block 29, as described above, the shift control response delay included in the target engine output _Te ^* (for canceling). a correction amount, output adjusted (target engine so that the target engine output T _e ^* not to induce proliferation of the engine output such that the above-mentioned problems To adjust the rate of change of T _e ^*)
The corrected target engine output _TeT is obtained, and this is used for throttle opening control (engine output control). Therefore, it is possible to prevent a sudden increase that may cause a problem of the engine output. Deterioration of drivability due to resonance or the like can be avoided.

In the above embodiment, the case where the response delay of the shift control is larger than the response delay of the engine output control has been described. Conversely, the response delay of the engine output control is larger than the response delay of the shift control. It is needless to say that the same object can be achieved by the same concept even when the value is large.

FIG. 3 shows another embodiment of the present invention. The driving force control device shown in FIG. 3 is obtained by adding an improvement according to the present invention to the driving force control device shown in FIG. The In this embodiment the transmission target input rotational speed N _pri ^* and the target engine output T _e ^*, determined as follows Unlike the previous embodiment. The required minimum axle driving force T _S calculated by the required axle driving force calculation unit 21 based on the accelerator pedal depression amount APS and the vehicle speed VSP is generated with a predetermined transient characteristic set in the transient target axle driving force calculation unit 26. the transitional target axle drive force T _ST is input to the transmission target input rotational speed calculation unit 33 for further inputs the vehicle speed detection value VSP from the sensor 19 to the arithmetic unit 33.

The transmission target input speed calculating section 33 calculates a map corresponding to, for example, the data shown in FIG. 9 obtained as follows from the transient target axle driving force T _ST and the vehicle speed VSP based on the characteristic diagram of the engine. Based on the current vehicle speed VSP
Obtains a target value N _e ^* of the engine speed N _e for generating under the transitional target axle drive force T _ST at minimum fuel consumption,
Then seeking the target engine speed N _e transmission target input rotation speed corresponding to the ^* (target primary rotation speed) N _pri ^*, it contributes to the calculation of the target speed ratio i ^* in the arithmetic unit 25.

Here, the data of FIG. 9 will be described. The data is obtained from the characteristic diagram of the engine shown in FIG. 7 as follows: the vehicle speed VSP, the axle driving force T _S, and the engine speed N _e. And the relationship. Figure 7 is already mentioned above, the engine speed N _e, the relationship between the engine output (torque) T _e, as iso-fuel consumption lines α fuel consumption rate becomes the same, also, equal horsepower output horsepower becomes the same The minimum fuel consumption line connecting points at which the fuel consumption rate is the best on each isohorsepower line β is indicated by δ. As in Figure 8 the individual points on a minimum fuel consumption line δ shown in FIG. 7, the gear ratio of the vehicle speed VSP to the engine speed N _e by (about including coefficients which), also the engine output (torque) to T _e transaxle marked shift to the two-dimensional coordinate system by replacing the force T _S, when determining the combination of vehicle speed VSP and the engine output (torque) T _e of the lowest fuel consumption per speed ratio, becomes a as shown in FIG.

[0055] When the plots points engine speed N _e to the diagram characteristic line for each gear ratio is equal, in the case of certain engine speed N _e, it is assumed such indicated by A in FIG. 8, these points signed a, indicating the relationship between the vehicle speed VSP and the axle drive force T _S for each engine speed N _e, 7
Can be represented by a line as shown in FIG. In FIG 9, for convenience, it denoted the engine speed N _e as the target engine speed N _e ^*, also showed to also shown the transient target axle drive force T _ST to the axle drive force T _S.
According to the data indicating the relationship between the vehicle speed VSP, the transient target axle driving force T _ST, and the target engine speed N _e ^* ,
The case where the combination of the current vehicle speed VSP and the transient target axle driving force T _ST corresponds to, for example, the point Z will be described. The transient target axle driving force T _ST is generated at the minimum fuel efficiency under the vehicle speed VSP. Target engine speed N _e ^* can be obtained as a parameter value (engine speed) related to a line passing through the point Z in FIG. In a vehicle with a continuously variable transmission, the torque converter 6 is in a lock-up state in which input and output elements are directly connected for most of the time during power transmission. was, but with the handling of the transmission target input revolution speed (target primary rotation speed) N _pri ^* as the same value for the target engine speed N _e ^*.

On the other hand, in the present embodiment, unlike the case of FIG. 2, the shift delay correction amount adjusting section is arranged in front of the target engine output calculating section 28 as indicated by 31. Therefore, in the present embodiment, the transient target axle driving force T _ST , which is the data for obtaining the target engine output T _e ^* itself, instead of the target engine output T _e ^* itself as in the embodiment of FIG. According to the same effect as the adjustment unit 29, the corrected transient target axle driving force T _SC is corrected by adjusting the correction amount for eliminating the transient excess or deficiency of the axle driving force due to the shift response delay.

Next, in the target engine output calculation section 28,
The corrected transient target axle driving force T _SCThe wheel drive system
Speed ratio i_TDivided by the corrected transient target vehicle
Shaft driving force T_SCEngine to achieve the lowest fuel consumption
Output (torque) T_e ^*Find this target engine output
(Torque) T_e ^*Target throttle opening calculator 3 based on
0, the target engine output (torque) T_e ^*Occurs
Target throttle opening TVO^*Figure 1
Output to the step motor 4 as shown
To the target throttle opening TVO^*Opening control so that
I do.

[0058] The above-described in the present embodiment, the request transaxle force T _S a manner such as to generate the transient target axle drive force T _ST to achieve the transient characteristics defined in the calculating unit 26 at a minimum fuel consumption Speed control of continuously variable transmission (i ^* )
And engine throttle opening control (TVO ^* ). And this time, with the actual speed ratio wheel drive system real speed ratio i _T target engine output T _e ^*
To determine the in the target engine output T _e ^* itself, than the engine output control already become those considering the response delay of the larger shift control response delay, therefore the target engine output T _e ^*, shift be those increased or decreased corrected to compensate for changes in delay of the transient target axle drive force T _ST due to the response delay, the throttle opening control (engine output control) and shift control based on the target speed ratio i ^* based on this, the Despite the shift response delay, the transient target axle driving force T _ST can be realized faithfully one by one.

Further, the transient target axle driving force _{TST is applied} to the shift delay correction amount adjustment unit 31 in the same manner as the shift delay correction amount adjustment unit 29 in FIG. 2, that is, the target engine output _Te ^* is a problem. In order to prevent such a sudden increase in engine output from occurring, the corrected transient is corrected by adjusting the correction amount to eliminate the transient excess or deficiency of the axle driving force due to the shift response delay. The target axle driving force T _SC is obtained, and this is used for calculating the target engine output _Te ^*. Therefore, when the response delay of the shift control is significantly larger than the response delay of the engine output control, a sudden increase in the accelerator pedal depression amount may be used. request transaxle force T _S, thus even when the transitional target transaxle force T _ST increases rapidly, it is possible to prevent the surge as a problem of the engine output, which is the vehicle body and drive due It is possible to avoid the deterioration of the drivability due to torsional resonance of the system occurs.

FIG. 4 shows still another embodiment of the present invention. The driving force control device shown in FIG. 4 is based on the driving force control device shown in FIG. 11, and the engine is assisted by an auxiliary power source 40 such as an electric motor. In such a case, the shift response delay is compensated for, and the correction amount therefor is adjusted so as not to cause a sudden increase in the engine output, which may cause a problem. Therefore, in the present embodiment, the transient target axle driving force T _ST is distributed at a predetermined ratio between the engine side and the auxiliary power source side, and the engine side target driving force T _ST1 and the auxiliary power source side target driving force T _ST are distributed. A driving force distribution amount calculation unit 41 for _{obtaining ST2} is provided.

[0061] By the target engine output computing section 28 for dividing the engine-side target driving force T _ST1 in wheel drive system actual gear ratio i _T, the target engine for generating an engine-side target driving force T _ST1 output T _e ^* The shift delay main correction amount adjustment unit 42 is the same as the shift delay correction amount adjustment unit 29 in FIG. 2, and the shift response delay amount automatically included in the target engine output _Te ^* as described above. The correction amount (for offset) is adjusted so as not to cause a sudden increase in the engine output such that the target engine output _Te ^* becomes a problem, and the corrected target engine output _TeT is obtained.

This corrected target engine output T_eTBased on
The target throttle opening calculating section 30 calculates the corrected target
Engine output T_eTTarget throttle opening T at which
VO ^*To the step motor 4 as shown in FIG.
The throttle valve 5 to the target throttle opening TVO
^*The opening is controlled so that

On the other hand, the auxiliary power source side target driving force T _ST2 from the driving force distribution amount calculating section 41 is input to the shift delay correction amount sub-adjustment section 43. Here, the shift delay correction amount sub-adjustment unit 43
Is the same as the shift delay correction amount adjustment unit 31 in FIG. 3. The auxiliary power source-side target drive force T _ST2 is calculated by the calculation unit 41 based on the transient excess / deficiency of the axle drive force due to the shift response delay. The target auxiliary driving force T _A ^* is obtained by correcting by adjusting the correction amount for compensating at the same ratio as the distribution ratio to be obtained,
This is input to the auxiliary power source 40.

The adjustment amount by the shift delay main correction amount adjustment unit 42 and the adjustment amount by the shift delay correction amount sub-adjustment unit 43 correspond to the distribution ratio in the arithmetic unit 41, and the sum of both adjustment amounts However, it is a matter of course that the engine output should not be increased so as to cause a problem such as a sudden increase in engine output.

In the present embodiment, the output of the engine and the auxiliary power source 40 are individually controlled to make the total output correspond to the transient target axle driving force T _ST , and the response delay of the shift control having the largest response delay Thus, the control target values of the engine and the auxiliary power source 40 are corrected so that the axle driving force deviation caused by the vehicle is canceled. The same operation and effect as those in the embodiment shown in FIGS. 2 and 3 can be obtained.

FIG. 5 shows yet another embodiment of the present invention.
The drive force control device shown in FIG. 5 compensates for the shift response delay in the device shown in FIG. 12, and adjusts the correction amount therefor so as not to cause a sudden increase in the engine output, which is a problem. The configuration is as follows. In the present embodiment, a transmission target input rotation speed / target engine output calculation unit 47 is provided instead of the transmission target input rotation speed calculation unit 24 in FIG.
When the transmission target input rotation speed _Npri ^* is determined based on the map corresponding to FIG. 7, the target engine output _Te ^* is also determined from the same map.

When the target engine output _Te ^* is obtained in this way, since the actual gear ratio is not involved in the calculation, the target engine output _Te ^* is determined by the transient of the driving force due to the shift response delay. It does not include the excess or deficiency, and it is difficult to faithfully achieve the transient target axle driving force T _ST ,
Its realization is delayed with a shift response delay. Therefore, in the present embodiment, the target engine output _Te ^* is first input to the shift delay correction unit 32. When the speed change of the continuously variable transmission is an upshift, the correction unit 32 determines that the engine output control amount is increased by a transient excessive amount of the axle driving force because the response delay of the speed change results in the delay of the reduction of the axle driving force. (Target throttle opening TVO ^* ) is reduced so that the target engine output T _e ^* is reduced, and the compensated target engine output T
and _eH, when the gear of the continuously variable transmission in reverse is downshifting, since the response delay of the speed change results in increased delay of the axle driving force, only transient deficiency of the axle drive force engine output control amount ( target throttle opening TVO ^*) in which is a target engine output T _e ^* was raised to compensated target engine output T _eH to be increased.

[0068] Such compensated target engine output T _eH is a result of the correction, but makes it possible to faithfully realize the transient target axle drive force T _ST despite shift response delay, on the other hand, the shift control response The above concern when the delay is significantly greater than that of engine power control,
Transient target axle driving force T _ST due to sudden increase in accelerator pedal depression
When the engine power suddenly increases, torsional resonance of the vehicle body and the drive system occurs due to the rapid increase of the engine output, and there is a concern that the drivability is deteriorated.

Therefore, the compensated target engine output T
The corrected target engine output _TeT after _eH is further corrected by the shift delay correction amount adjustment unit 29 as in FIG. 2 is used as calculation data of the target throttle opening TVO ^* in the calculation unit 30. Therefore, also in the present embodiment, when the response delay of the shift control is significantly larger than that of the engine output control, the above-mentioned concern, that is, when the transient target axle driving force T _ST suddenly increases due to a sudden increase in the accelerator pedal depression amount or the like, the engine is stopped. It is possible to eliminate a concern that the torsional resonance of the vehicle body or the driving system is caused by the sudden increase of the output and the drivability is deteriorated.

FIG. 6 shows still another embodiment of the present invention. The driving force control apparatus shown in FIG. 6 compensates for the shift response delay in the apparatus shown in FIG. 13 and corrects it. The amount is adjusted so as not to cause an abrupt increase in engine output, which is a problem. In the present embodiment, the transmission target input rotational speed _Npri ^* is obtained in the same manner as in FIG. 3, but the target throttle opening TVO ^* is obtained as follows.

That is, the wheel drive system target gear ratio calculator 45
By dividing the transmission target input speed N _{pr i} ^* by the axle speed N _S , the wheel drive system target speed ratio i
_T ^* is calculated, and the target engine output calculation unit 28 calculates
The target engine output (torque) T for realizing the transient target axle driving force T _ST with the minimum fuel consumption by dividing the transient target axle driving force T _ST from the calculating unit 26 by the wheel drive system target gear ratio i _T ^*. Calculate _e ^* .

[0072] Incidentally, if in the song obtaining the target engine output T _e ^*, since the actual speed ratio is used target speed ratio i _T ^* during the operation is not involved, the target engine output T _e ^* is shifting It does not include the transient excess or deficiency of the driving force due to the response delay, and it is difficult to faithfully achieve the transient target axle driving force T _ST , and the realization is delayed with the shift response delay. Therefore, in the present embodiment, the target engine output _Te ^* is first input to the shift delay correction unit 46. When the speed change of the continuously variable transmission is an upshift, the correction unit 46 determines that the engine output control amount is increased by a transient excessive amount of the axle driving force because the response delay of the speed change results in a decrease delay of the axle driving force. (Target throttle opening TV
O ^* ) is reduced to reduce the target engine output _Te ^* to the compensated target engine output _TeH . Conversely, if the shift of the continuously variable transmission is a downshift, the response delay of the shift is axle drive. since the result in increased delay of the force, the compensated target engine by raising the target engine output T _e ^* to transient shortfall by the engine output control amount of axle drive force (target throttle opening TVO ^*) is increased The output is _TeH .

[0073] Such compensated target engine output T _eH is a result of the correction, but makes it possible to faithfully realize the transient target axle drive force T _ST despite shift response delay, on the other hand, the shift control response The above concern when the delay is significantly greater than that of engine power control,
Transient target axle driving force T _ST due to sudden increase in accelerator pedal depression
When the engine power suddenly increases, torsional resonance of the vehicle body and the drive system occurs due to the rapid increase of the engine output, and there is a concern that the drivability is deteriorated.

Therefore, the compensated target engine output T
The corrected target engine output _TeT after _eH is further corrected by the shift delay correction amount adjustment unit 29 as in FIG. 2 is used as calculation data of the target throttle opening TVO ^* in the calculation unit 30. Therefore, also in the present embodiment, when the response delay of the shift control is significantly larger than that of the engine output control, the above-mentioned concern, that is, when the transient target axle driving force T _ST suddenly increases due to a sudden increase in the accelerator pedal depression amount or the like, the engine is stopped. It is possible to eliminate a concern that the torsional resonance of the vehicle body or the driving system is caused by the sudden increase of the output and the drivability is deteriorated.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory diagram showing a power train of a vehicle equipped with a continuously variable transmission equipped with a driving force control device according to an embodiment of the present invention, together with a control system thereof.

FIG. 2 is a functional block diagram of a shift control and a throttle opening control for driving force control executed by a controller in the embodiment.

FIG. 3 is a functional block diagram of a shift control and a throttle opening control for driving force control according to another embodiment of the present invention.

FIG. 4 is a functional block diagram of a shift control and a throttle opening control for driving force control according to still another embodiment of the present invention.

FIG. 5 is a functional block diagram of a shift control and a throttle opening control for driving force control according to still another embodiment of the present invention.

FIG. 6 is a functional block diagram of a shift control and a throttle opening control for driving force control according to still another embodiment of the present invention.

FIG. 7 shows an equal fuel consumption line, an equal horsepower line, and a two-dimensional coordinate line defined by an engine speed axis and an engine output torque axis.
FIG. 4 is a characteristic diagram of an engine showing a minimum fuel consumption line.

FIG. 8 is a diagram when the minimum fuel consumption line is rewritten as a relationship diagram between the vehicle speed and the axle driving force for each gear ratio.

9 is a relationship diagram between the vehicle speed and the axle driving force, which is a diagram connecting the points at which the input rotation speeds become equal for each speed ratio on the diagram of FIG. 9;

FIG. 10 is a functional block diagram illustrating an example of conventional general shift control and throttle opening control for driving force control.

FIG. 11 is a functional block diagram showing another example of conventional general shift control and throttle opening control for driving force control.

FIG. 12 is a functional block diagram showing another example of conventional shift control and throttle opening control for conventional driving force control.

FIG. 13 is a functional block diagram showing still another example of conventional general shift control and throttle opening control for driving force control.

[Explanation of symbols]

 Reference Signs List 1 engine 2 continuously variable transmission 3 accelerator pedal 4 step motor 5 electronically controlled throttle valve 6 torque converter 7 primary pulley 8 secondary pulley 9 V belt 10 final drive gear set 11 differential gear device 12 hydraulic actuator 13 controller 14 accelerator pedal travel sensor 16 Throttle opening sensor 17 Primary pulley rotation sensor 18 Secondary pulley rotation sensor 19 Vehicle speed sensor 21 Required axle driving force calculation unit 22 Axle rotation speed calculation unit 23 Required horsepower calculation unit 24 Transmission target input speed calculation unit 25 Target gear ratio calculation unit 26 Transient target axle drive force calculation unit 27 Wheel drive system actual gear ratio calculation unit 28 Target engine output calculation unit 29 Shift delay correction amount adjustment unit 30 Target throttle opening calculation unit 31 Shift delay correction amount adjustment unit 32 Shift delay Correction unit 33 Transmission target input speed calculation unit 40 Auxiliary power source 41 Driving force distribution amount calculation unit 42 Shift delay correction amount main adjustment unit 43 Shift delay correction amount sub-adjustment unit 45 Wheel drive system target gear ratio calculation unit 46 Shift delay correction unit 47 Transmission target input rotation Number and target engine output calculator

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F02D 45/00376 F02D 45/00 376C (72) Inventor Minori Iwasaki 2 Takaracho, Kanagawa-ku, Yokohama-shi, Kanagawa Nissan Inside the Automobile Co., Ltd. (72) Inventor Keiichi Kawashima 2 Takara-cho, Kanagawa-ku, Yokohama-shi, Kanagawa Nissan Motor Co., Ltd. (72) Inventor Hideaki Watanabe 2 Takara-cho, Kanagawa-ku, Yokohama-shi, Kanagawa F-term (reference) ) 3D041 AA31 AA66 AB01 AC01 AC09 AC15 AC20 AD10 AD30 AD51 AE02 AE04 AE36 AF01 AF09 3G065 DA06 EA04 EA13 FA02 FA12 GA11 GA31 GA46 KA02 KA36 3G084 BA00 BA05 BA32 CA04 CA08 DA05 DA15 EB08 BA05 A03 FA05 FA05 DA06 DB05 EA09 EB03 EC02 EC04 FA07 FA10 FB01 FB03

Claims (4)

[Claims] 1. A vehicle equipped with a power train which is a combination of an engine whose output can be arbitrarily changed by a factor other than the operation of an accelerator pedal and a continuously variable transmission, wherein the vehicle has a driving state and running conditions which are different from each other. A combination of a target engine speed and a target engine output for realizing the transient target axle driving force obtained from the determined required axle driving force is determined, and the transmission target input speed corresponding to the target engine speed is obtained. While controlling the speed change of the step transmission,
An output control of the engine is performed so that the target engine output is obtained. The control target value of the shift response and the engine output control having the smaller response delay is an axle driving force deviation caused by the response delay of the larger response delay. In the driving force control apparatus for a vehicle which is corrected so as to cancel, the correction amount for canceling the axle driving force deviation with respect to the control target value of the smaller response delay, the required axle driving force and the transient target axle. A driving force control device for a vehicle, wherein the control is performed separately from the driving force so as to suppress a sudden change in the control target value having the smaller response delay. 2. The engine according to claim 1, wherein the engine is assisted by an auxiliary power source, and the output of the engine and the auxiliary power source is individually controlled so that the total output becomes the target engine output. An engine output control system and an auxiliary power source such that an axle driving force deviation caused by a response delay of a shift control having the largest response delay among the output control of the engine, the output control of the auxiliary power source, and the shift control is cancelled. When the control target value of the output control system is corrected, the correction amount for offsetting the axle driving force deviation with respect to the control target values of the engine output control system and the auxiliary power source output control system is individually set to both values. A driving force control device for a vehicle, wherein the driving force control device is configured to adjust so as to suppress a sudden change in a total of control target values. 3. The axle driving force deviation according to claim 1, wherein the output control of the engine and / or the output control of the auxiliary power source and the shift control of the shift control having the largest response delay among the shift controls. When correcting the control target value of the engine output control system and / or the auxiliary power source output control system so that the components are canceled, the target engine output is obtained by dividing the transient target axle driving force by the actual gear ratio. A driving force control device for a vehicle, wherein the target engine output is the one that has been subjected to the above-described correction by itself. 4. The axle driving force deviation according to claim 1, wherein the output control of the engine and / or the output of the auxiliary power source and the shift control having the largest response delay among the shift controls are caused by a response delay. When correcting the control target value of the engine output control system and / or the auxiliary power source output control system so as to cancel the component, the target engine output is obtained based on the required horsepower corresponding to the transient target axle driving force. Alternatively, the target engine output is calculated by dividing the transient target axle driving force by a target gear ratio obtained from the transient target axle driving force, and the target engine output is calculated by axle driving caused by a response delay of the shift control. A driving force control device for a vehicle, wherein a correction is made so that a force deviation is canceled.