JP2005337053A - Drive torque control device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a drive torque control device for a vehicle improving a incompatible sense felt by a driver at down shift. <P>SOLUTION: The drive torque control device for the vehicle is provided with a target drive torque operation part 20 for operating target drive torque from the driving state of the vehicle; and an engine torque instruction value operation part 21 for operating an engine torque instruction value based on the target drive torque. The device is provided with an engine torque instruction value correction part 22 for presuming variation of the driving torque due to delay of response of actual engine torque variation accompanying with variation of a shift ratio and correcting the engine torque instruction value. Fluctuation of the drive torque due to delay of response is reduced. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a vehicle drive torque control device, and more particularly to drive torque control during downshifting.

Conventionally, an output command value (target drive torque x output shaft rotation angular velocity) is input to achieve the target drive torque obtained based on the driver's acceleration operation amount (accelerator opening) and the vehicle state quantity, and the iso-output line An input shaft rotational speed (speed ratio) command value is calculated using a map created based on the input shaft rotational speed obtained from the intersection of the engine operating point and the engine operating point. Patent Document 1 discloses a technique for calculating an engine torque command value by dividing a target drive torque by an actual speed ratio and a final reduction ratio.
JP 2001-047891 A

  However, in the above invention, the engine torque command value is calculated without considering the response delay of the engine. For example, when the gear ratio command is downshifted and the engine torque changes, the actual engine torque change is The reaction occurs later than the engine torque command value, and a deviation occurs between the engine torque command value and the actual engine torque (actual engine torque). As a result, the driving torque (actual driving torque) becomes larger than the target value, that is, the acceleration of the vehicle becomes larger than the acceleration corresponding to the accelerator opening by overshoot, and the driver feels uncomfortable. There is a problem.

  The present invention has been invented to solve such problems. The deviation between the engine torque command value and the actual engine torque is reduced, the vehicle is given acceleration according to the driver's operation, and the driver feels. The purpose is to improve the sense of incongruity.

  In the present invention, target drive torque calculation means for calculating the target drive torque from the driving state of the vehicle, engine torque calculation means for calculating the engine torque command value based on the target drive torque, and the actual engine torque follows the engine torque command value. In a vehicle driving force control device comprising an engine torque control means for controlling the engine to estimate the fluctuation of the driving torque due to a delay in response to a change in the actual engine torque accompanying a change in the gear ratio, the engine torque command value is corrected Engine torque command value correction means is provided.

  Also included is a target speed ratio calculating means for calculating a target speed ratio of the automatic transmission based on the driving state of the vehicle, and a speed ratio control means for controlling the speed ratio of the automatic transmission based on the target speed ratio. .

  According to the present invention, the deviation between the engine torque command value and the actual engine torque can be reduced, and the fluctuation of the drive torque due to the response delay of the actual engine torque can be reduced. The uncomfortable feeling felt by the driver can be improved by increasing the torque fluctuation.

  The configuration of the embodiment of the present invention will be described with reference to the schematic configuration diagram of FIG.

  The power train of the present invention includes an engine 1, a torque converter 2 with a lockup mechanism, and a continuously variable transmission (hereinafter referred to as CVT) 3.

  The engine 1 controls the output torque by adjusting the intake air to the engine 1 by the electronically controlled throttle actuator 1a.

  The torque converter 2 includes a lock-up mechanism (not shown). The lock-up mechanism is opened only in the extremely low speed region of the engine output, and can start from the stop of the vehicle in the open state, and further dampens vibrations. . In the middle and high speed range, the output of the engine 1 is partially or completely transmitted to the CVT 3 by fastening between the input and output shafts of the torque converter 2 by a lockup mechanism and adjusting the fastening force.

  The CVT 3 is provided between the primary pulley 4 connected to the torque converter 2, the secondary pulley 5 connected to the vehicle drive side, the primary pulley 4 and the secondary pulley 5, and a belt 6 that transmits the rotation of the primary pulley 4 and the secondary pulley 5. The effective radius of the primary pulley 4 and the secondary pulley 5 is adjusted by a hydraulic mechanism to control the gear ratio. The CVT 3 is not limited to a belt type continuously variable transmission, and a toroidal continuously variable transmission may be used.

  The controller that controls the vehicle includes a drive torque controller 10 that controls the drive torque of the vehicle, an engine torque controller 11 that controls the engine torque, and a CVT controller 12 that controls the gear ratio of the CVT 3 and the clutch. These controllers include a CPU, ROM, RAM, digital port, A / D port, one-chip microcomputer with built-in various timer functions (or a functional chip that realizes the same functions), high-speed communication circuits, and actuator drive circuits. Consists of.

  Further, as sensors for detecting the state of the vehicle to be controlled by the controller, an accelerator sensor 13 for measuring the accelerator opening operated by the driver, a wheel speed sensor 14 for detecting the rotational speed of the wheel, an engine crankshaft ( An engine rotation speed sensor (crank angle sensor) 15 that is mounted on a primary pulley shaft of the CVT 3 and that detects the rotation speed of the primary pulley; and a CVT 3 A secondary rotational speed sensor 17 that detects the rotational speed of the secondary pulley, and an engine operating point restraint line switching SW 18 that switches whether the operating point of the engine 1 is focused on fuel efficiency or acceleration. . The wheel speed sensor 14, the engine speed sensor 15, the primary speed sensor 16, and the secondary speed sensor 17 use an electromagnetic pickup or the like. The engine operating point restraint line switching SW 18 is operated by the driver and is provided, for example, near the shift lever.

  The engine torque control system of the drive torque controller 10 will be described with reference to the block diagram of FIG.

  The engine torque control system of the drive torque control controller 10 calculates an engine torque command value from the target drive torque calculation unit (target drive torque calculation means) 20 for calculating the target drive torque of the vehicle, and the actual transmission ratio of the target drive torque and CVT3. An engine torque command value calculation unit (engine torque calculation means) 21 for calculating, and an engine torque command value correction for calculating a final engine torque command value obtained by correcting the engine torque command value from the target drive torque, the engine torque command value, and the actual gear ratio. And an engine torque control section (engine torque control means) 23 for controlling the torque of the engine 1.

  Next, processing contents of the drive torque controller 10 will be described with reference to the flowchart of FIG. The flowchart of FIG. 3 is performed every predetermined time, for example, every 10 msec.

In step S1, an accelerator signal is read by an A / D port provided in the accelerator sensor 13 from the amount of depression of the driver, and the accelerator opening _Apo is measured.

  In step S2, the wheel speed Vw of the drive wheel is calculated from the reciprocal of the wheel speed pulse width (n cycles) measured using the input capture function which is one of the timer functions of the microcomputer provided in the wheel speed sensor 14. To do.

  In step S3, the ON / OFF state of the engine operating point constraint line switching SW18 is determined using the digital I / O port of the microcomputer.

In step S 4, the primary rotational speed ω _p is measured from the primary speed sensor 16, the secondary rotational speed ω _s is measured from the secondary speed sensor 17, and the speed ratio I _p calculated by the CVT controller 12 is measured from the crank angle sensor 15. The rotational speed ω _e is read from the high-speed communication reception buffer.

In step S5, the target drive torque calculator 20 calculates the target drive torque T _d ^* based on the accelerator opening A _po and the wheel speed V _w . The target drive torque T _d ^* is read from the map shown in FIG. FIG. 4 is a map showing the target driving torque T _d ^* with respect to the accelerator opening A _po and the wheel speed V _w . As the accelerator opening A _po increases, the target driving torque T _d ^* increases and the wheel speed V _w increases. The target drive torque T _d ^* decreases as the speed decreases.

Further, here, the filter processing of the expression (1) constituted by the engine transfer characteristic G _e ′ (s) and a predetermined transfer characteristic G _t (s) set in advance with respect to the target drive torque T _d ^*. Thus, phase compensation (first phase compensation) may be performed. This can further reduce the driver's uncomfortable feeling. In the actual calculation, calculation is performed using a recurrence formula obtained by discretization by Tustin approximation or the like (step 5 constitutes a target drive torque phase compensation means).

式（１）の位相補償を施すことにより、実駆動トルクＴ_dを設計時に予め設定した伝達特性とすることができる。なお、ここでの位相補償は、式（１）に限られず、或る所定の伝達特性Ｇ_t（ｓ）を異なる伝達特性とすることも可能である。

By applying the phase compensation of equation (1), the actual drive torque T _d can be made to have a transfer characteristic preset at the time of design. Here, the phase compensation is not limited to the expression (1), and a certain predetermined transfer characteristic G _t (s) can be set to a different transfer characteristic.

  Further, feedback control may be performed on the target driving torque (or acceleration) so that the target actual driving torque can be obtained even when a disturbance such as a road surface gradient occurs. (Step S5 constitutes a target engine drive torque calculation means).

In step S6, a map shown in target driving torque T _d ^*, the drive wheel angular velocity ω _w (ω _w = wheel speed V _w / tire radius) and 5 in advance stored in memory from the state of engine operation point constraint line switching SW18 Thus, the target primary rotational speed ω _p ^* is read out. FIG. 5 is a diagram showing the relationship between the equal output line (drive torque × driving wheel angular velocity), the engine operating point constraint line, the primary rotational speed ω _p ^*, and the engine torque, and the intersection of the equal output line and the engine operating point constraint line. To read the target primary rotational speed ω _p ^* . In addition, when the engine torque is positive, that is, when driving at constant speed or acceleration, the engine operating point constraint line is the optimum fuel efficiency driving line that emphasizes fuel efficiency, and the acceleration performance is emphasized with a margin in engine torque. The acceleration priority line is selected, and the driver selects one of the engine operating point constraint lines by operating the engine operating point constraint line switching SW18. When the engine torque is a negative value, an engine brake characteristic line is shown. In FIG. 5, among the engine operating point constraint lines, the optimum fuel efficiency operation line is indicated by a solid line, the acceleration emphasis line is indicated by a broken line, the equal output line is indicated by a two-dot chain line, and the equal fuel consumption consumption line is indicated by a one-dot chain line. Each area surrounded by a one-dot chain line is an equal fuel consumption area.

In step S7, from the target primary rotational speed ω _p ^* ,
I _p ^* = ω _p ^* / ω _s formula (2)
Based on the above, a gear ratio command value I _p ^* which is a target gear ratio is calculated (step S7 constitutes a target gear ratio calculating means).

In step S8, the engine torque command value calculator 21 calculates the target drive torque T _d ^* and the actual transmission ratio I _p of the continuously variable transmission,
T _e ^* = T _d ^* / (I _p × I _f ) Equation (3)
Is calculated based on the basic engine torque command value _Te ^* , which is the torque command value of the engine 1 with respect to the target drive torque. Here, I _{f is the} final reduction ratio (step S8 constitutes engine torque calculation means).

In step S9, the engine torque command value correction unit 22 uses the target drive torque _Td ^* or the basic engine torque command value _Te ^* and the actual gear ratio _Ip to change the actual engine torque with respect to the engine torque command value change accompanying the gear ratio change. A delay (deviation) is estimated, an actual driving torque fluctuation due to the delay is estimated, and a final engine torque correction value _{Te_ERR} 'for calculating the _fluctuation is calculated. Details of the engine torque command value correction unit 22 will be described later.

In step S10, the basic engine torque command value T _e ^* calculated in step S8, 'adds the final engine torque command value T _e ^*' final engine torque correction value T _{E_ERR} calculated in step S9 calculates a. As a result, the delay of the actual engine torque with respect to the change in the torque command value is corrected, so that it is possible to prevent the actual drive torque from greatly deviating from the target drive torque (steps S9 and S10 constitute the engine torque command value correcting means, Step S10 constitutes final engine torque command value calculation means).

In step S11, the final engine torque command value _Te ^* 'is output to the engine torque controller 11 and the gear ratio command value _Ip ^* is output to the CVT controller 12 via a high-speed communication line. ^* of the engine torque to the engine torque command value T _e ', and controls the speed ratio command value I _p ^* the gear ratio of the primary pulley 4 and secondary pulley 5 of CVT 3 (step S11 the engine torque control means, the gear ratio control means Constitute).

  By the above control, for example, the actual driving torque greatly deviates from the target driving torque at the time of downshift due to a change in the engine operating point constraint line due to the operation of the engine operating point constraint line switching SW 18 by the driver or an increase in the accelerator opening (target drive It is possible to prevent the actual driving torque from becoming larger than the torque and deviating toward the acceleration side), and to reduce the uncomfortable feeling given to the driver or the like.

Next, FIG. 6 for details of the engine torque command value correcting section 22 for calculating a final engine torque correction value T _e _ _ERR 'in step S9, FIG. 7 will be described with reference to the block diagram of FIG. FIG. 7 is a block diagram when the filtering process is not performed in Step 5, and FIG. 8 is a block diagram when the filtering process is performed in Step 5. The engine torque command value correction unit 22 calculates a drive torque reference value from a target drive torque and an actual gear ratio, a drive torque reference value calculation unit 30 (drive torque reference value calculation means) that calculates a drive torque reference value from the target drive torque. A drive torque estimated value calculation unit 31 (drive torque estimated value calculation means) for calculating, and an engine torque correction value calculation unit 32 (engine torque correction value calculation means for calculating an engine torque correction value from the drive torque reference value and the drive torque estimated value) ), And a final engine torque command value calculating unit 33 (final engine torque command value calculating means) for calculating a final engine torque command value from the engine torque command value and the engine torque correction value.

The drive torque reference value calculation unit 30 receives the target drive torque T _d ^* calculated by the delay processing unit 40 in step S5 as an input, and delays the transfer characteristic G ₁ (s) shown in the equation (4) or the equation (5) ( (Temporary delay + dead time) processing is performed, and a drive torque reference value T _{d — REF} is calculated when it is assumed that there is no delay in the change in the engine torque command value due to the change in the gear ratio. Actually, the calculation is performed using a recurrence formula obtained by discretization by Tustin approximation or the like. Equation (4) is a transfer characteristic when the target drive torque is not subjected to the phase compensation shown in Equation (1) in Step 5, and Equation (5) is shown in Equation (1) as the target drive torque in Step 5. This is a transfer characteristic when phase compensation is performed.

ただし、τ_e：エンジンの一次遅れ時定数、Ｌ_e：むだ時間、であり、これらの値は図９、１０に基づいて設定される。図９はエンジン１の回転速度とエンジン１の一次遅れ時定数の関係を示した図であり、エンジン回転速度が速くなると、エンジンの一次遅れ時定数は減少する。また、図１０はエンジン１の回転速度とむだ時間の関係を示した図であり、エンジン回転速度が速くなるとむだ時間は減少する。ステップＳ５において目標駆動トルクに式（１）に示す位相補償を行った場合には式（５）の伝達特性を施すことで、エンジントルク規範値における駆動トルクの遅れ処理を精度良く行うことができる。

However, τ _{e is the} primary delay time constant of the engine, L _{e is the} dead time, and these values are set based on FIGS. FIG. 9 is a diagram showing the relationship between the rotational speed of the engine 1 and the primary delay time constant of the engine 1. As the engine rotational speed increases, the primary delay time constant of the engine decreases. FIG. 10 is a diagram showing the relationship between the rotational speed of the engine 1 and the dead time. The dead time decreases as the engine rotational speed increases. When the phase compensation shown in equation (1) is performed on the target drive torque in step S5, the drive torque delay process in the engine torque reference value can be performed with high accuracy by applying the transfer characteristic of equation (5). .

In the drive torque estimated value calculation unit 31, first, the engine torque command value _Te ^* 'calculated in step S8 by the delay processing unit 41 is subjected to a delay process corresponding to the engine transfer characteristic shown in the equation (4), thereby changing the engine torque command value change amount. delay calculates the engine torque estimation value T _e _ _EST when occurred. When feedback control is performed in step S5, the engine torque command value _Te ^* obtained by dividing the target drive torque before correction by feedback is delayed by the engine transmission characteristic of equation (4). processing performed may be computed engine torque estimated value T _e _ _EST. As a result, the engine torque can be corrected without impairing the feedback stability.

Then, the engine torque estimated value T _e _ _EST and the actual speed ratio I _p and the final reduction ratio I _f, the integrating unit 42,
T _{d_EST} = T _{e_EST} × I _p × I _f formula (6)
Thus, a drive torque estimated value T _{d _EST} when a delay occurs in the engine torque command value change is calculated.

In the engine torque correction value calculating section 32, first, the driving torque reference value T _d _ _REF from the drive torque estimation value T _{D_EST,} the addition unit 43,
T _{d_ERR} = T _{d_REF} −T _{d_EST} expression (7)
Thus, the drive torque fluctuation T _{d — ERR} caused by the delay in the engine torque command value change is calculated.

Next, the calculated drive torque fluctuation T _{d — ERR} is calculated from the actual speed ratio I _p and the final reduction ratio _If by the division unit 44. _{Te_ERR} = T _d — _ERR / (I _p × I _f ) Expression (8)
To calculate the engine torque correction value _{Te_ERR} .

The calculated engine torque correction value _{Te_ERR} is subjected to a phase compensation filter (second phase compensation) represented by the following equation (9) in the phase compensation unit 45 to calculate a final engine torque correction value _{Te_ERR} '. The actual calculation is performed using a recurrence formula obtained by discretization by Tustin approximation or the like.

ただし、τ₁、τ₂：位相補償定数であり、ここではτ₂を上述したエンジン一次遅れ時定数（τ_e）とする。τ₂をエンジン一次遅れ時定数とすることによりエンジントルクの遅れと位相補償を同期することでエンジンの応答特性が変化した場合でも安定した位相補償を得ることができる。

However, τ ₁ and τ _{2 are} phase compensation constants. Here, τ ₂ is the engine primary delay time constant (τ _e ) described above. By using τ ₂ as the engine primary delay time constant, the engine torque delay and the phase compensation are synchronized, so that stable phase compensation can be obtained even when the response characteristic of the engine changes.

Final engine torque command value calculating unit 33 calculates the basic engine torque command value T _e ^* and the final engine torque correction value T _e _ _ERR 'from the final engine torque command value T _e ^*' as described in step S10 .

As described above, the final engine torque command value _Te ^* ′ is calculated by the engine torque command value correction unit 22.

  With the above control, the actual engine torque response delay process is performed on the engine torque command value to calculate the final engine torque correction value that can bring the fluctuation of the actual drive torque closer to the actual drive torque when there is no response delay. can do.

  Next, a case where the present invention is not used and an actual driving torque change when the present invention is used will be described with reference to time charts shown in FIGS. FIG. 11 is a diagram showing changes in actual driving torque and the like when the engine operating point constraint line switching SW 18 is operated from the fuel efficiency priority line to the acceleration priority line without using the present invention. It is a figure which shows changes, such as an actual drive torque at the time of using.

First, the case where the present invention is not used will be described. Before time t1, the accelerator opening A _po1 , the gear ratio I _p1 , the engine torque T _e1 , and the actual driving torque T _d1 are in a state where the accelerator opening is constant and the driving torque is balanced with the running resistance, that is, the vehicle speed is constant. State.

Then, at time t1, the driver switches the engine operating point constraint line switching SW18 to change from the fuel efficiency priority line to the acceleration priority line. As a result, the gear ratio command value is changed from I _p1 to I _p2 , that is, changed in the downshift direction. Note that, when the gear ratio command value changes, a mechanical delay occurs with respect to the command value. Here, the time is assumed to be t2.

  At time t2, the engine torque command value is output based on the gear ratio command, and the engine torque command value decreases with the downshift. However, the actual engine torque (actual value in the figure) reacts with a delay with respect to the engine torque command value due to, for example, a fuel transportation delay, and a deviation occurs between the engine torque command value and the actual engine torque. Even if the engine operating point restraint switching SW18 is changed, the actual driving torque is constant without changing the driving torque reference value (target value in the figure) because the accelerator opening is constant when there is no deviation. However, if there is a deviation, the actual drive torque (actual value in the figure) changes in an increasing direction because there is a difference between the actual change in the gear ratio and the actual change in the engine torque. As a result, the actual drive torque increases until time t3 when the actual engine torque starts to decrease with a response delay with respect to the engine torque command value, and then decreases with a decrease in the actual engine torque. At this time, although the accelerator opening is constant, the actual driving torque greatly increases, which may make the driver feel uncomfortable.

  At time t4, the actual gear ratio becomes the gear ratio command value, and at time t5, the actual engine torque becomes the engine torque command value, and the actual drive torque matches the drive torque reference value.

  When the present invention is used, the fluctuation due to the response delay of the actual engine torque with respect to the engine torque command value is estimated and corrected. Up to time t2, it is the same as the case where the present invention is not used.

  The engine torque command value (steps S9 and S10) corrected from time t2 decreases. Here, when the engine torque command value is corrected and compared with the engine torque command value before correction, the engine torque command value after correction increases its rate of change (decrease rate) to t3 ′, and then the engine torque command value. Reduce the rate of change (increase rate). Thereby, although a slight deviation occurs, the actual engine torque can be brought close to an engine torque command value corresponding to a change in the gear ratio, that is, an engine torque change that does not cause a change in the actual drive torque. As a result, the actual driving torque becomes close to the driving torque reference value, and the uncomfortable feeling due to the change in the actual driving torque felt by the driver or the like can be reduced. The engine torque command value by correction may be other than the change shown in FIG. 12, and the actual drive torque can be brought close to the drive torque reference value by correcting the engine torque command value.

  At time t4 ', the actual gear ratio becomes the shift command value, the actual engine torque becomes the engine torque command value, and the actual drive torque matches the drive torque reference value. Note that the actual gear ratio and the actual engine torque may not match the gear ratio command value or the engine torque command value at the same time, but even in this case, the actual gear ratio and the actual engine torque are not compared until the time t4 to the time t5 shown in FIG. Time can be shortened.

  Further, the case where the present invention is not used when the accelerator opening is opened and the actual driving torque change when the accelerator opening is used will be described with reference to time charts shown in FIGS. FIG. 13 is a diagram showing changes in actual driving torque or the like when the driver increases the accelerator opening without using the present invention, and FIG. 14 shows changes in actual driving torque or the like when the present invention is used. FIG.

First, a time chart when the present invention is not used will be described. Before time t1, the accelerator opening A _po3 , the gear ratio I _p3 , the engine torque T _e3 , the actual driving torque T _d3 , the accelerator opening is constant, and the actual driving torque is balanced with the running resistance, that is, the vehicle speed is constant. It is driving in the state of.

Then, at time t1, the accelerator is depressed by the driver, the accelerator opening is changed from A _po3 to A _PO4. As a result, the gear ratio command value changes from I _p3 to I _p4 , the engine torque command value changes from T _e3 to T _e4 , and the actual drive torque target value changes from T _d3 to T _d4 . Note that when the engine torque command value changes, a mechanical delay occurs with respect to the command value. Here, the engine torque change start is defined as t2.

  At time t2, the actual engine torque starts to increase as the accelerator opening increases. Further, the actual driving torque increases with the increase of the engine torque.

It issued the engine torque command value so that the engine torque is reduced based on the time the gear ratio in t3 changes, decreases the engine torque command value T _e4 with the downshift for acceleration to T _e5. However, the actual engine torque reacts with a delay with respect to the engine torque command value due to, for example, a throttle delay, and a deviation occurs between the engine torque command value and the actual engine torque. Due to this deviation, the actual drive torque changes in a direction of increasing from the drive torque reference value when there is no deviation.

  At time t4, the actual driving torque that is larger than the driving torque reference value due to the deviation causes an overshoot, and becomes larger than the driving torque reference value corresponding to the driver's accelerator depression amount. Therefore, the acceleration is higher than the acceleration required by the driver, which makes the driver feel uncomfortable. The drive torque increases until time t5 when the product of the actual engine torque and the actual gear ratio decreases.

  After time t5, the actual engine torque decreases, and the actual drive torque also decreases. At time t6, the actual gear ratio becomes the gear ratio command value, and at time t7, the actual engine torque becomes the engine torque command value, and the actual drive torque also It matches the drive torque standard value.

  When the present invention is used, the fluctuation due to the delay of the actual engine torque with respect to the engine torque command value is estimated and corrected. Up to time t2, it is the same as the case where the present invention is not used. Further, at time t2, the actual engine torque starts to increase due to the increase in the accelerator opening, and the actual driving torque increases as the engine torque increases.

  From time t3 ', the corrected engine torque command value (steps S9, S10) decreases with the downshift. Here, when the engine torque command value is corrected, the rate of change (decrease rate) of the corrected engine torque command value increases until time t4 ′ as compared with the engine torque command value before correction, and then the engine torque Reduce the change rate of the command value. Since the actual engine torque changes according to the corrected engine torque command value, a slight deviation occurs, but the deviation can be reduced and the actual driving torque can be brought close to the driving torque reference value. As a result, the actual driving torque becomes close to the driving torque reference value, that is, the fluctuation of the actual driving torque is reduced, and the uncomfortable feeling due to the change in the actual driving torque felt by the driver or the like can be reduced. Note that the engine torque command value by correction may be other than the change shown in FIG. 14, and the actual drive torque approaches the drive torque reference value by correcting the engine torque command value.

  At time t <b> 5 ′, the actual driving torque becomes larger than the driving torque reference value and causes an overshoot. However, the amount is smaller than that in the case where the present invention is not used, and the uncomfortable feeling felt by the driver can be reduced.

  At time t6 ', the actual gear ratio becomes the shift command value, the actual engine torque becomes the engine torque command value, and the actual drive torque matches the drive torque reference value. Note that the actual gear ratio and the actual engine torque may not coincide with the gear ratio command value or the engine torque command value at the same time, but even in this case, the actual gear ratio and the actual engine torque are not compared until the time t6 to the time t7 shown in FIG. Time can be shortened.

  The effect of 1st Embodiment of this invention is demonstrated.

  In the present invention, when the engine torque changes with a change in the gear ratio, the fluctuation in the actual driving torque due to the engine response delay is estimated in the engine torque command value, and the response is delayed by correcting the engine torque command value. The deviation between the engine torque command value and the actual engine torque when there is no response is reduced, and the difference between the actual drive torque and the actual actual drive torque when there is no response delay is reduced. As a result, for example, when the engine operating point restraint line switching SW 18 is operated, or when downshifting due to the driver depressing the accelerator, an increase in the actual driving torque caused by a response delay of the engine torque can be reduced. The uncomfortable feeling felt by the driver can be improved.

  The engine torque correction can be performed with high accuracy by using the engine transmission characteristic (Equation (4)) as the engine delay characteristic transmission characteristic in the drive torque reference value calculation unit 30 and the drive torque estimated value calculation unit 31. it can. Further, when feedback control is performed on the target drive torque (step 5), a delay process is performed on the target drive torque before the feedback control is performed, so that the engine torque can be reduced without impairing the stability of the feedback control. Correction can be performed.

  Further, when phase compensation (equation (1)) is performed on the target drive torque, the drive torque reference value calculation unit 30 performs delay processing according to phase compensation (equation (1)), thereby Correction can be performed with high accuracy.

Since the engine primary delay time constant (τ _e ) and engine dead time (L _e ) of the transmission characteristic (equation (4)) for performing the delay process of the engine 1 are set according to the engine operating state, the operating state of the engine 1 Accordingly, the delay process of the engine 1 can be performed to correct the engine torque accurately.

By proceeding to the engine torque correction value and applying phase compensation (Equation (9)), the engine torque response delay can be reduced and the engine torque can be corrected more accurately. Further, by setting the phase compensation constant (τ ₂ ) of the lead phase compensation to the primary delay time constant (τ _e ) of the engine 1, the engine torque can be corrected more accurately according to the operating state of the engine.

  It goes without saying that the present invention is not limited to the above-described embodiments, and includes various modifications and improvements that can be made within the scope of the technical idea.

  It can be used for vehicles that are equipped with an automatic transmission and perform driving force control.

It is a schematic block diagram of this invention. It is a block diagram of the drive torque control controller of this invention. It is a flowchart which the drive torque control controller of this invention performs. It is a map which calculates the target drive torque of this invention. It is a map which calculates the rotational speed of the target primary pulley of this invention. It is a block diagram which shows the engine torque command value correction | amendment part of this invention. It is a block diagram which shows the engine torque command value correction | amendment part of this invention, and is a block diagram when not performing phase compensation to the target drive torque. It is a block diagram which shows the engine torque command value correction | amendment part of this invention, and is a block diagram in the case of performing phase compensation to a target drive torque. It is a map which calculates the first-order lag time constant of the engine of this invention. It is a map which calculates the dead time of the engine of this invention. It is a time chart when the engine operating point restraint line switching SW is operated when the present invention is not used. It is a time chart when the engine operating point restraint line switching SW is operated when the present invention is used. It is a time chart when the accelerator opening is opened when the present invention is not used. It is a time chart when the accelerator opening is opened in the case of using the present invention.

Explanation of symbols

1 Engine 2 Torque converter 3 Continuously variable transmission (CVT)
4 Primary pulley 5 Secondary pulley 10 Drive torque control controller 11 Engine torque controller 12 CVT, clutch controller 18 Engine operating point constraint line switching SW
20 Target drive torque calculation unit (target drive torque calculation means)
21 Engine torque command value calculation unit (engine torque calculation means)
22 Engine torque command value correction unit (engine torque command value correction means)
23 Engine torque control unit (engine torque control means)
30 Drive torque reference value calculation unit (drive torque reference value calculation means)
31 Drive torque estimated value calculation unit (drive torque estimated value calculation means)
32 Engine torque correction value calculation unit (engine torque correction value calculation means)
33 Final engine torque command value calculation unit (final engine torque command value calculation means)

Claims (9)

Target drive torque calculating means for calculating the target drive torque from the driving state of the vehicle;
Engine torque calculation means for calculating an engine torque command value based on the target drive torque;
An engine torque control means for controlling the engine so that the actual engine torque follows the engine torque command value;
A vehicle drive torque control device comprising engine torque command value correction means for estimating a fluctuation in drive torque due to a response delay of the actual engine torque change accompanying a change in gear ratio, and correcting the engine torque command value. The engine torque calculation means calculates an engine torque command value by dividing the target drive torque by an actual gear ratio,
The engine torque command value correction means performs a direct delay process on the target drive torque, and calculates a drive torque reference value calculation means when the fluctuation of the drive torque does not occur;
A drive torque estimated value calculation that calculates a drive torque estimated value when the torque fluctuation occurs by multiplying the actual speed ratio after delay processing is performed on the result of dividing the target drive torque by the actual speed ratio Means,
Engine torque correction value calculating means for calculating a final engine torque correction value from the drive torque reference value and the drive torque estimated value;
The vehicle drive torque control device according to claim 1, further comprising final engine torque command value calculation means for calculating a final engine torque command value from the engine torque command value and the final engine torque correction value.   The engine torque correction value calculation means calculates the engine torque correction value by dividing a deviation between the drive torque reference value and the drive torque estimated value by the actual gear ratio. Vehicle drive torque control apparatus.   The vehicle drive torque control device according to claim 2 or 3, wherein a transmission characteristic of delay processing in the drive torque reference value calculation means and the drive torque estimated value calculation means is an engine transfer characteristic. A target drive torque phase compensation means for performing phase compensation on the target drive torque by a first phase compensation comprising an engine transfer characteristic and a predetermined transfer characteristic;
When the target drive torque is subjected to first phase compensation by the target drive torque phase compensation means,
The transfer characteristic of delay processing in the drive torque reference value calculation means is the predetermined transfer characteristic,
4. The vehicle drive torque control device according to claim 2, wherein a transfer characteristic of delay processing in the drive torque estimated value calculation means is a transfer characteristic of the engine.   6. The vehicle drive torque control device according to claim 4, wherein the engine transfer characteristic is a transfer characteristic including a Laplace operator, an engine first-order lag time constant, and an engine dead time.   The vehicle torque control device according to claim 6, wherein the first-order engine delay time constant and the engine dead time are set based on a state of the engine.   8. The final engine torque correction value according to claim 4, wherein a second phase compensation is applied to the engine torque correction value calculated from the drive torque reference value and the drive torque estimated value. The vehicle drive torque control device according to claim 1.   9. The vehicle drive torque control apparatus according to claim 8, wherein the second phase compensation is phase compensation that has at least a first-order lag time constant of the engine and is synchronized with a transfer characteristic of the engine.

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