JP2008001131A - Driving force controller for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To evade a feeling of strangeness in a plurality of gear shifts in the case of achieving a target acceleration following access operation by engine output control and gear shift control. <P>SOLUTION: An operation part 41 finds out a target acceleration tACC of a vehicle, an operation part 42 finds out target driving force tF for achieving the tACC and the tF is passed through a phase comparator 431 having a transmission function Ga(s) = äGre(s)/Ge(s)} which is a combination of an inverse system ä1/Ge(s)} of a controlled model Ge(s) and a norm response model Gre(s) to find out demanded driving force demFENG for operating an engine torque command value. An operation part 52 finds out a target gear shift from the force tF and an actual vehicle speed aVSP. The force tF is subjected to phase compensation to obtain the phase-compensated demanded driving force demFENG, the engine torque command value cTE is determined on the basis of the phase-compensated demanded driving force demFENG, but the target gear shift tSHIFT is determined on the basis of the target driving force tF obtained before phase compensation. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention is for controlling the driving force of a vehicle through output control of an engine and shift control of an automatic transmission so as to realize a target acceleration corresponding to a driving state of the vehicle such as a driver's accelerator operation by an accelerator pedal. It relates to the device.

As such a driving force control device for a vehicle, a device as described in Patent Document 1, for example, is conventionally known.
The driving force control device described in this document obtains the target acceleration of the vehicle from the accelerator pedal depression amount and the actual vehicle speed, then obtains the driving force feedforward control amount for achieving the target acceleration, and further calculates the target acceleration. The above driving force feedforward control amount is corrected by the driving force feedback compensation amount for eliminating the vehicle speed deviation between the target vehicle speed obtained by integration and the actual vehicle speed, so that the target driving force is not obtained, engine output control and The driving force of the vehicle is made to coincide with the target driving force by the shift control of the automatic transmission.

  Incidentally, the above-mentioned response delay unavoidable in terms of control is required for the feedforward control system for obtaining the above-mentioned driving force feedforward control amount even though the control target actually operates with a predetermined response delay with respect to the control command value. Is not taken into consideration, and there is a problem that the intended effect cannot be achieved.

Conventionally, a control technique as described in Patent Document 2 has been known as a control technique considering such a response delay.
In this technology, the target deceleration is obtained from the brake pedal depression force and the deceleration immediately before the braking operation, and then the braking force feedforward control amount for achieving the target deceleration is obtained. Further, the target deceleration and the actual deceleration are obtained. The braking force feedforward control amount is corrected by the braking force feedback compensation amount for eliminating the deceleration deviation between the speed and the target braking force, and the vehicle braking force is matched with this target braking force. Assuming
In order to match the response of the controlled object to the reference response characteristics (ideal response of the host vehicle) in the feedforward control system for determining the braking force feedforward control amount, the inverse system of the response model Ge (s) of the controlled object {1 / Ge (s)} and a phase compensator having a transfer function Ga (s) = {Gre (s) / Ge (s)} that is a combination of the reference response model Gre (s),
The braking force control is performed so that the braking force of the vehicle matches the required braking force after phase compensation of the target braking force by this phase compensator.

  When phase compensation is performed in this way, the above braking force control can be performed with the ideal response characteristics defined by the norm response model Gre (s), despite the inevitable response delay of the controlled object, and the target reduction is achieved. Speed can be achieved as intended.

Therefore, in order to solve the problem of the driving force control device described in Patent Document 1, that is, the problem that the driving force control as intended cannot be performed due to the response delay of the controlled object, Patent Document 1 Applying the phase compensation technology described in Patent Document 2 to the described driving force control device,
It can be considered that a phase compensator based on the same concept as the phase compensation technique described in Patent Document 2 is provided in the feedforward control system for obtaining the driving force feedforward control amount in Patent Document 1.

The feedforward control system of the driving force control device based on this concept is as shown in FIG.
That is, in the target acceleration calculation unit, the target acceleration tACC of the vehicle is obtained from the accelerator pedal depression amount (accelerator opening APO) and the actual vehicle speed aVSP,
A target driving force calculation unit obtains a target driving force tF (driving force feedforward control amount) for achieving the target acceleration tACC from the target acceleration tACC and the vehicle weight.
Then, this target driving force tF is converted into a transfer function Ga (s) = {which is a combination of the inverse system {1 / Ge (s)} of the response model Ge (s) to be controlled and the reference response model Gre (s). Through a phase compensator having Gre (s) / Ge (s)}, a required driving force ffF for realizing the target driving force tF with a normative response (ideal response of the host vehicle) is obtained.
In the engine torque command value calculation unit, the engine torque command value cTE is obtained from the required driving force ffF and the actual gear ratio aRATIO,
In the target gear stage calculation unit, the target gear stage of the automatic transmission is obtained from the required driving force ffF and the actual vehicle speed aVSP,
The driving force of the vehicle is made to coincide with the above-mentioned required driving force ffF by engine output control and automatic transmission shift control performed to realize the engine torque command value cTE and the target shift stage.
JP 2003-170759 A JP 2003-170823 A

  By the way, in the case of the above-described driving force control device in which the phase compensation technique described in Patent Document 2 is applied to the driving force control device described in Patent Document 1, the phase compensator is as follows at the time of shifting to switch the shift stage of the automatic transmission: This causes problems such as

As shown in FIG. 16, when the accelerator opening APO is increased stepwise at the instant t1, the target driving force tF increases in response to this, as shown in the figure.
When the phase compensator of the transfer function Ga (s) = {Gre (s) / Ge (s)} is to compensate for the target driving force tF, the required driving force ffF on the output side of the phase compensator Is temporarily larger than the target driving force tF on the input side, as shown.

By the way, the target shift speed tSHIFT is determined according to the required driving force ffF as shown in FIG. 15, and the temporarily increased required driving force ffF reaches the second speed range from the fourth speed range through the third speed range. In order to finally settle down to the third speed range, the target gear stage tSHIFT reaches from the fourth speed to the second speed through the third speed and finally becomes the third speed.
For this reason, the overshoot of the required driving force ffF is 2 times downshift (4 → 3, 3 → 2) and 1 time upshift (2 → 3) in a short period of time. There is a concern that a certain speed change will occur and a speed change shock will occur as is apparent from changes in A1, A2 and A3 of the actual driving force aF at every speed change.

The present invention is based on the recognition that the above-mentioned problem is to determine the target shift stage that is the shift control command value of the automatic transmission based on the required driving force on the output side of the phase compensator.
The shift control command value is determined based on the target driving force before phase compensation, so that repeated downshifts and upshifts due to overshoot of the required driving force do not occur. An object of the present invention is to propose a driving force control apparatus.

For this purpose, a driving force control device for a vehicle according to the present invention as described in claim 1,
In the driving force control device that makes the driving force of the vehicle the target driving force for the target acceleration by the output control of the engine and the shift control of the automatic transmission so that the target acceleration according to the driving state of the vehicle is achieved,
A phase compensator is provided that performs phase compensation on the target driving force to obtain a required driving force,
The command value for the engine output control is determined based on the required driving force on the output side of the phase compensator, and the command value for the shift control is determined by the target driving force on the input side of the phase compensator. It is characterized by having comprised so that it may determine based on.

According to the configuration of the present invention, the target driving force is phase-compensated to obtain the required driving force, the command value for engine output control is determined based on the required driving force after phase compensation, and for the shift control Because the command value is determined based on the target driving force before phase compensation,
The engine output control takes into account the inevitable response delay of the controlled object, while avoiding problems caused by this,
The shift control of the automatic transmission is performed while eliminating the influence of the overshoot of the required driving force due to phase compensation.

Therefore, it is possible to avoid the problem that the target acceleration cannot be generated as intended due to the response delay of the engine output control,
The problem that the shift of the automatic transmission is repeatedly downshifted and upshifted due to the influence of the overshoot of the required driving force after phase compensation can be avoided.

Hereinafter, embodiments of the present invention will be described in detail based on the embodiments shown in 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 its control system. The power train is composed of an engine 1 and a stepped automatic transmission 2.
The engine 1 is a gasoline engine, but the throttle valve 3 is not mechanically connected to the accelerator pedal 4 that is operated by the driver, but is separated from these to be electronically controlled by the throttle actuator 5. To make.

  The throttle actuator 5 operates according to a target throttle opening tTVO output in response to an engine torque command value cTE described later by the engine controller 6 so that the opening of the throttle valve 3 matches the target throttle opening tTVO. The output of the engine 1 is basically controlled to be a value corresponding to the operation of the accelerator pedal 4, but depending on how the engine torque command value cTE is given, it can be controlled by factors other than the accelerator pedal operation. To do.

The automatic transmission 2 is a well-known planetary gear set type automatic transmission, and the engine 1 is connected to the input shaft via a torque converter (not shown) and the wheel drive system is connected to the output shaft via a differential gear device (not shown). To do.
The automatic transmission 2 includes a control valve body 7 for shift control, and this control valve body 7 responds to a shift solenoid signal output by the transmission controller 8 in response to a target shift stage tSHIFT described later, It is assumed that the automatic transmission 2 is shifted from the currently selected shift speed toward the target shift speed tSHIFT.

The engine torque command value cTE to the engine controller 6 and the target shift stage tSHIFT to the transmission controller 8 are respectively determined by the driving force control controller 11 through calculations described later.
Therefore, the driving force control controller 11 includes a signal from the accelerator opening sensor 12 that detects the depression amount (accelerator opening) APO of the accelerator pedal 4, and
A signal from the driving wheel speed sensor 13 for detecting the rotational peripheral speeds Vw1 and Vw2 of the left and right driving wheels, and
A signal from the brake switch 14 that is turned on during braking when a brake pedal (not shown) is depressed,
A signal related to the selected shift stage aSHIFT from the transmission controller 8;
When the driver desires the driving force control according to the present invention, the driver inputs a signal from the driving force control switch 15 to be turned on.

The controller 11 for driving force control reads these input information at regular control intervals by a scheduled interrupt, executes the process shown in the functional block diagram in FIG. 2 based on these input information, as follows: An engine torque command value cTE to the engine controller 6 and a target gear stage tSHIFT to the transmission controller 8 are obtained.
The engine controller 6 and the transmission controller 8 perform the throttle opening (output) control of the engine 1 and the shift control of the automatic transmission 2 based on the engine torque command value cTE and the target shift stage tSHIFT, respectively. Carry out driving force control of the target vehicle.

  As shown in FIG. 2, the driving force control controller 11 includes a driving force control availability determination unit 20, an actual vehicle speed calculation unit 30, a required driving force calculation unit 40, and a driving force distribution unit 50. Details will be described sequentially.

The driving force control availability determination unit 20 executes the control program shown in FIG. 3 to determine whether or not driving force control should be performed, and sets the result by 1 or 0 of the driving force control execution flag fSTART.
In step S1 in FIG. 3, it is checked whether the driving force control switch 15 is ON or OFF, and then in step S2, it is checked whether the brake switch 14 is ON or OFF.

While it is determined in step S1 that the driving force control switch 15 is ON (the driver desires driving force control) and in step S2, it is determined that the brake switch 14 is OFF (not braking), the driver The driver desires driving force control and is in a non-braking state where this control can be performed, so in step S3 it is determined that driving force control should be performed and the driving force control execution flag fSTART is set to 1. Set to.
However, while it is determined in step S1 that the driving force control switch 15 is OFF (the driver does not desire driving force control) or in step S2, it is determined that the brake switch 14 is ON (braking). Even if the driver does not want to control the driving force, or even if he / she desires, the driving force control does not function effectively because the brake is being applied. Therefore, in step S4, it is determined that the driving force control should not be performed. Reset the control execution flag fSTART to 0.

Here, the reason why the driving force control is not performed while the brake switch 14 is ON (during braking) is that even if the engine output control and the shift control according to the present invention are performed during braking, This is because the driving force control cannot be achieved and the control itself is wasted.
When the driving force control according to the present invention is always performed regardless of the driver's will, the driving force control switch 15 is not necessarily required, and the brake switch 14 is turned on (during braking) and off (non-braking). The driving force control execution flag fSTART may be set or reset only according to braking.
The driving force control execution flag fSTART set as described above is supplied not only to the required driving force calculation unit 40 but also to the engine controller 6 and the transmission controller 8 as shown in FIG.

While the driving force control execution flag fSTART is 1, the engine controller 6 and the transmission controller 8 are based on the engine torque command value cTE and the target shift stage tSHIFT from the driving force control controller 11 so that these are achieved. The target throttle opening tTVO to the throttle actuator 5 and the shift solenoid command to the control valve body 7 are determined, and the driving force control according to the present invention is performed.
However, while the driving force control execution flag fSTART is 0, the throttle opening control of the engine 1 and the accelerator opening APO according to only the accelerator opening APO, as usual, instead of the driving force control according to the present invention described above. It is assumed that the shift control of the automatic transmission 2 is performed according to the vehicle speed.

  The actual vehicle speed calculation unit 30 in FIG. 2 calculates an average value of the left and right drive wheel speeds Vw1 and Vw2, and inputs this to the required drive force calculation unit 40 and the drive force distribution unit 50 as the actual vehicle speed aVSP.

As shown in FIG. 4, the required driving force calculation unit 40 includes a target acceleration calculation unit 41, a target driving force calculation unit 42, a feedforward compensation unit 43, a feedback compensation unit 44, and adders 45 and 46. And
The required driving force demFENG for calculating the engine torque command value and the required driving force demFAT for calculating the target gear stage are calculated from the accelerator opening APO and the actual vehicle speed aVSP.

The target acceleration calculation unit 41 obtains the target acceleration tACC of the vehicle from the accelerator opening APO and the actual vehicle speed aVSP based on the map illustrated in FIG.
As is clear from FIG. 5, the target acceleration tACC increases as the accelerator opening APO increases, and decreases as the actual vehicle speed aVSP increases.
The target driving force calculation unit 42 obtains the target driving force tF necessary to realize the target acceleration tACC by multiplying the target acceleration tACC by the vehicle weight.

  The feedforward compensation unit 43 is as shown in FIG. 6, and from the target driving force tF and the actual vehicle speed aVSP, the required driving force feedforward compensation value ffFENG for calculating the engine torque command value and the required driving force feedforward compensation for calculating the target gear stage. In order to obtain the value ffFAT, a phase compensator 431, a reference response model time constant calculation unit 432, and a target shift speed calculation required driving force feedforward compensation value selection switch 433 are provided.

The phase compensator 431 performs phase compensation on the target driving force tF so that the acceleration response (engine torque response characteristics) to be controlled matches the reference response model Gre (s) of ideal response characteristics, and after phase compensation The required driving force feedforward compensation value ffF of
Therefore, the transfer function Ga (s) = {Gre (s) / which is a combination of the inverse {1 / Ge (s)} of the response model Ge (s) to be controlled and the reference response model Gre (s) Ge (s)}.
The feedforward compensation unit 43 outputs the requested driving force feedforward compensation value ffF from the phase compensator 431 as it is as the requested driving force feedforward compensation value ffFENG for calculating the engine torque command value.

Here, the norm response model Gre (s) and the engine torque response characteristic Ge (s) are both expressed by a first-order transfer function using the time constant Tre of the norm response model and the time constant Te of the engine torque characteristic. Therefore, the transfer function Ga (s) of the phase compensator 431 is as shown by the following equation.
Ga (s) = {Gre (s) / Ge (s)}
= {(Te · s + 1) / (Tre · s + 1)}
Actually, the transfer function Ga (s) of the phase compensator 431 is calculated using a recurrence formula obtained by discretization by Tustin approximation or the like.

The reference response model time constant calculation unit 432 determines the time constant Tre of the reference response model Gre (s) from the actual vehicle speed aVSP based on the map illustrated in FIG. 7, and uses the time constant Tre determined here to determine the phase. The transfer function Ga (s) of the compensator 431 is calculated by the above equation.
In the map illustrated in FIG. 7, while the actual vehicle speed aVSP is less than VSP1, the transfer function Ga (s) of the phase compensator 431 performs phase compensation in the forward direction with respect to the target driving force tF, and the actual vehicle speed aVSP is equal to or higher than VSP1. In the meantime, it is assumed that the transfer function Ga (s) of the phase compensator 431 performs phase compensation in the delay direction with respect to the target driving force tF.
In the above description, the case where the time constant Tre is changed according to the actual vehicle speed aVSP and the transfer function Ga (s) of the phase compensator 431 is operated is described. Without being limited thereto, it can also be determined according to the driving environment of the vehicle, the driver's habit, and the like.

The requested driving force feedforward compensation value selection switch 433 for target shift speed calculation is supplied with the required driving force feedforward compensation value ffF after phase compensation on the output side of the phase compensator 431 to the “slow” input, and the “advance” input The target driving force tF before phase compensation is supplied to
While the transfer function Ga (s) of the phase compensator 431 applies phase compensation in the delay direction to the target driving force tF (while the actual vehicle speed aVSP is VSP1 or higher), the required driving force feedforward compensation value ffF after phase compensation is Output as required driving force feedforward compensation value ffFAT for target gear position calculation,
While the transfer function Ga (s) of the phase compensator 431 applies phase compensation in the forward direction to the target driving force tF (while the actual vehicle speed aVSP is less than VSP1), the target driving force tF before phase compensation is calculated as the target gear stage. The required driving force feedforward compensation value ffFAT is output.

  In FIG. 6, the target driving force tF before phase compensation is supplied as it is to the “advance” input of the target driving speed calculation required driving force feedforward compensation value selection switch 433. The force tF may be supplied to the “advance” input of the switch 433 after passing through the reference response model Gre (s) or other compensator having delay characteristics.

  The feedback compensation unit 44 in FIG. 2 is as shown in FIG. 8, and in order to obtain the required driving force feedback compensation value fbF from the target acceleration tACC and the actual vehicle speed aVSP, the engine model 441 and the reference response model time constant calculation unit 442 And an acceleration calculation unit 443, a subtractor 444, and a feedback compensator 445.

The engine model 441 has a transfer function Gb (s) = Gre (s) · e- ^Ls set with the reference response model Gre (s) and the same ^dead time Td as the controlled object, and wastes the target acceleration tACC. Time processed and output.
The transfer function Gb (s) of the engine model 441 is similar to the reference response model Gre (s) in the feedforward compensation unit 43, and the reference response model time constant calculation unit 442 (the same as the calculation unit 432 in FIG. 6). It depends on the norm response model time constant Tre obtained in step 1.
The acceleration calculation unit 443 performs an approximate differentiation process on the actual vehicle speed aVSP to calculate the actual acceleration aACC. Actually, the acceleration calculation unit 443 is applied to a first-order high-pass filter having a transfer function Ghpf (s) expressed by the following equation. The actual acceleration aACC is obtained by passing through the speed aVSP.
Ghpf (s) ＝ s / (Ta ・ s + 1)
Where Ta: Time constant of the high-pass filter

The subtractor 444 obtains an acceleration deviation ΔACC = tACC−aACC between the target acceleration tACC subjected to dead time processing by the engine model 441 and the actual acceleration aACC,
The feedback compensator 445 obtains a required driving force feedback compensation value fbF for eliminating the acceleration deviation ΔACC and making the actual acceleration aACC coincide with the target acceleration tACC after the dead time processing.
This required driving force feedback compensation value fbF is for suppressing the influence of disturbance and modeling error.
As the feedback compensator 445, a PID compensator comprising a proportional gain Kp, an integral gain Ki, and a differential gain Kd is used here.
The transfer function Gfb (s) of the feedback compensator 445 is given by the following equation.
Gfb (s) = Kp + (Ki / s) + s · Kd

  Of the adders 45 and 46 in FIG. 2, the adder 45 adds the requested driving force feedforward compensation value ffFENG for calculating the engine torque command value and the requested driving force feedback compensation value fbF, and adds the sum of the two to the engine. Torque command value calculation required driving force demFENG is output, and the adder 46 adds the target gear speed calculation required driving force feedforward compensation value ffFAT and the required driving force feedback compensation value fbF, and adds the sum of both. Output as required driving force demFAT for target gear position calculation.

  The driving force distribution unit 50 in FIG. 2 is as shown in FIG. 9, and from the actual vehicle speed aVSP, the actual gear ratio aRATIO, the required driving force demFENG for calculating the engine torque command value, and the required driving force demFAT for calculating the target gear stage, In order to calculate the torque command value cTE and the target gear stage tSHIFT, an engine torque command value calculator 51 and a target gear stage calculator 52 are provided.

The engine torque command value calculation unit 51 calculates the engine torque command value by calculating the following equation using the required driving force demFENG for engine torque command value calculation and the actual gear ratio aRATIO, the tire effective radius rTIRE, and the final reduction ratio Gf. Calculate cTE.
cTE = (demFENG × rTIRE) / (Gf × aRATIO)
The target shift speed calculation unit 52 uses the shift map illustrated in FIG. 10 to calculate the target for achieving the required drive force demFAT based on the actual vehicle speed aVSP from the actual vehicle speed aVSP and the target drive speed calculation required drive force demFAT. Determine the gear stage tSHIFT (1st to 5th).

  The engine torque command value cTE and the target gear stage tSHIFT obtained as described above are respectively commanded to the engine controller 6 and the transmission controller 8 as shown in FIG. 2, and the controllers 6 and 8 have the driving force control execution flag fSTART set. 1, the throttle opening (output) control of the engine 1 and the shift control of the automatic transmission 2 are performed based on the engine torque command value cTE and the target shift stage tSHIFT, and the vehicle driving force targeted by the present invention Carry out control.

This driving force control will be summarized below.
The actual vehicle speed aVSP is less than VSP1 in FIG. 7, and the transfer function Ga (s) of the phase compensator 431 in FIG. 6 performs phase compensation in the forward direction with respect to the target driving force tF. The switch 433 in the figure outputs the target driving force tF before phase compensation based on the position of the broken line as the required driving force calculation forward driving force feedforward compensation value ffFAT, and the driving force control for obtaining the target shifting step tSHIFT based on this is output. As shown in FIG.

That is, first, the target acceleration calculation unit 41 (see FIG. 4) obtains the target acceleration tACC of the vehicle from the accelerator opening APO and the actual vehicle speed aVSP.
In the next target driving force calculation unit 42 (see FIG. 4), a target driving force tF for achieving the target acceleration tACC is obtained by multiplying the target acceleration tACC and the vehicle weight,
This target driving force tF is determined by a transfer function Ga (s) = {Gre which is a combination of the inverse system {1 / Ge (s)} of the response model Ge (s) to be controlled and the reference response model Gre (s). The engine torque command value for realizing the target driving force tF with the reference response (ideal response of the vehicle) through the phase compensator 431 (see Fig. 6) with (s) / Ge (s)} Calculate the required driving force demFENG for computation.
In the engine torque command value calculation unit 51 (see FIG. 9), the engine torque command value cTE is obtained from the required driving force demFENG and the actual gear ratio aRATIO, and the throttle opening is electronically controlled so that this is achieved.

In the target shift speed calculation unit 52 (see FIG. 9), the target shift speed of the automatic transmission is obtained from the target driving force tF and the actual vehicle speed aVSP input as described above via the switch 433 in FIG.
By performing the shift control of the automatic transmission so as to realize the target shift stage tSHIFT, the driving force of the vehicle is matched with the target driving force tF in combination with the engine torque control.

By the way, according to the present embodiment, as is apparent from FIG. 11, phase compensation is performed on the target driving force tF to obtain the required driving force demFENG, and the engine torque command value cTE is determined based on the required driving force demFENG after phase compensation. Since the command value for shifting control (target shift stage tSHIFT) is determined based on the target driving force tF before phase compensation,
The engine output control can be controlled while avoiding problems due to the inevitable response delay of the control target by installing the phase compensator 431.
The shift control of the automatic transmission can be controlled while eliminating the influence of the overshoot of the required driving force due to phase compensation.

Therefore, the problem that the target acceleration cannot be generated as intended due to the response delay of the engine torque control can be avoided, and
The problem that the shift of the automatic transmission is repeatedly downshifted and upshifted due to the influence of the overshoot of the required driving force after phase compensation can be avoided.

The latter operation and effect will be supplemented by FIG. 12, which is an operation time chart under the same conditions as in FIG.
When the accelerator opening APO is increased stepwise at the instant t1, and the target driving force tF increases rapidly as shown in the figure, the transfer function Ga (s) = {Gre (s) / Ge ( s)} phase compensator 431 performs advance compensation on the target driving force tF as described above, so that the required driving force demFENG on the output side of the phase compensator 431 is the target driving force on the input side as shown in the figure. There is a concern that it temporarily becomes larger than tF (overshoots), causing a shift with a sense of incongruity many times as described above with reference to FIG. 16, and also causing a number of shift shocks.

In the present embodiment, as is apparent from FIG. 11, the target shift stage tSHIFT is determined based on the target driving force tF before phase compensation, and the target driving force tF is determined by the accelerator opening APO as shown in FIG. The level corresponding to this change is not exceeded and there is no overshoot to the 2nd speed range after shifting from the 4th speed range to the 3rd speed range.
Therefore, the downshift from the fourth speed to the third speed is performed only once, and the shift shock is not conspicuous.

  As described above with reference to FIG. 6, the transfer function Ga (s) of the phase compensator 431 is switched between the lead compensation characteristic and the delay compensation characteristic by the time constant Tre of the reference response model obtained by the calculation unit 432, With the switch 433 that responds to this switching, the target driving force tF on the input side of the phase compensator 431 is used in the calculation of the target shift stage tSHIFT in the case of lead compensation, and the phase compensation in the calculation of the target shift stage tSHIFT in the case of delay compensation. FIG. 13 shows an outline of driving force control using the required driving force demFENG on the output side of the unit 431.

When the transfer function Ga (s) of the phase compensator 431 performs lead compensation, the target driving force tF on the input side of the phase compensator 431 contributes to the calculation of the target shift stage tSHIFT. The same effects as those obtained can be obtained.
When the transfer function Ga (s) of the phase compensator 431 performs delay compensation, the required driving force demFENG on the output side of the phase compensator 431 contributes to the calculation of the target shift stage tSHIFT. It is done.

When the transfer function Ga (s) of the phase compensator 431 performs delay compensation, the required driving force demFENG on the output side of the phase compensator 431 is apparent from FIG. 14 showing a time chart under the same conditions as FIG. Therefore, even if the target shift stage tSHIFT is calculated based on this required driving force demFENG, there are many problems related to shifting with a sense of incongruity many times as described above with reference to FIG. There is no problem with multiple shift shocks.
Therefore, when the transfer function Ga (s) of the phase compensator 431 performs delay compensation, the required driving force demFENG on the output side of the phase compensator 431 as described above contributes to the calculation of the target shift stage tSHIFT.
According to this, the downshift accompanying the increase in the accelerator opening APO can be delayed from the accelerator depression instant t1 in FIG. 14 to the instant t2, and the selection time of the high gear can be lengthened. The fuel consumption can be improved by reducing the friction loss.

1 is a schematic system diagram showing a vehicle power train including a driving force control device according to an embodiment of the present invention, together with a control system thereof. FIG. 2 is a block diagram according to function of driving force control through shift control of an automatic transmission and engine throttle opening control, which is executed by a driving force control controller in the control system of FIG. FIG. 3 is a flowchart showing a control program executed by a driving force control availability determination unit in FIG. 2 to determine whether or not to perform driving force control according to the present invention. FIG. 3 is a block diagram showing details of a required driving force calculation unit in FIG. FIG. 5 is a map diagram to be used when a target acceleration calculation unit in FIG. 4 calculates a target acceleration. FIG. 5 is a detailed block diagram of a feedforward compensation unit in FIG. It is a change characteristic figure of a standard response model response time constant. FIG. 5 is a detailed block diagram of a feedback compensation unit shown in FIG. FIG. 2 is a detailed block diagram of a driving force distribution unit in FIG. FIG. 10 is a shift map diagram used when a target shift speed calculation unit in FIG. 9 obtains a target shift speed. FIG. 11 is a conceptual diagram when the phase compensator of the driving force control apparatus according to the embodiment shown in FIGS. 1 to 10 performs lead compensation. It is an operation | movement time chart in case the phase compensator of the driving force control apparatus by the Example performs advance compensation. FIG. 11 is a conceptual diagram of the driving force control apparatus according to the embodiment shown in FIGS. It is an operation | movement time chart in case the phase compensator of the driving force control apparatus by the Example performs delay compensation. It is a block diagram which shows the conventional driving force control apparatus. It is an operation | movement time chart of the same driving force control apparatus.

Explanation of symbols

1 engine
2 Continuously variable transmission
3 Accelerator pedal
4 Throttle actuator
5 Throttle valve
6 Torque converter
7 Primary pulley
8 Secondary pulley
9 V belt
10 Final drive gear set
11 Differential gear unit
12 Shift control hydraulic circuit
13 Step motor
14 Engine controller
15 Transmission controller
16 Driving force control controller
17 Accelerator position sensor
18 Engine rotation sensor
19 Vehicle speed sensor
20 Brake switch
21 Driving force control switch
30 Driving force control availability determination unit
40 Target vehicle speed calculator
41 Target acceleration determination unit
42 Integration processing section
50 Target driving force calculator
51 Phase compensator
52 Reference model
53 Feedback compensator
54 Drive torque converter
55 Vehicle model
60 Actual gear ratio calculator
70 Driving force distributor
71 Gear ratio command value setting section
72 Engine torque command value calculator
80 Target vehicle speed offset judgment section
81 Accelerator pedal operation speed calculator
82 Accelerator pedal operation acceleration calculator
83 Vehicle speed offset calculator

Claims (2)

In the driving force control device that makes the driving force of the vehicle the target driving force for the target acceleration by the output control of the engine and the shift control of the automatic transmission so that the target acceleration according to the driving state of the vehicle is achieved,
A phase compensator is provided that performs phase compensation on the target driving force to obtain a required driving force,
The command value for the engine output control is determined based on the required driving force on the output side of the phase compensator, and the command value for the shift control is determined by the target driving force on the input side of the phase compensator. A driving force control device for a vehicle, characterized in that it is determined based on the above. The driving force control apparatus according to claim 1, wherein the phase compensator is capable of changing a compensation characteristic.
When the phase compensator performs advance compensation on the target driving force to obtain a required driving force, a command value for the shift control is determined based on the target driving force on the input side of the phase compensator. When the phase compensator performs delay compensation on the target driving force to obtain the required driving force, the command value for the shift control is determined based on the required driving force on the output side of the phase compensator A driving force control apparatus for a vehicle, characterized in that

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