JP2005343422A - Driving force control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicular driving torque control device capable of improving a sense of inconguity felt by a driver in downshifting. <P>SOLUTION: This device is provided with a target acceleration calculation part 20 for calculating target acceleration from a driving state, a basic driving torque command value calculation part 21 for calculating basic driving torque based on the target acceleration, an acceleration calculation part 28 for calculating acceleration of a vehicle, and an inertia torque calculation part 32 for estimating inertia torque from the driving state. The device is further provided with a feedback compensation part 23 equipped with a first driving torque correction value calculation part 29 for calculating a first driving torque correction value based on a deviation between the target acceleration and the acceleration and a second driving torque correction value calculation part 30 for calculating a second driving torque correction value based on the deviation between the target acceleration and the acceleration and the inertia torque. The device is furthermore provided with a command value calculation part 27 equipped with an engine torque command value calculation part 31 for calculating an engine torque command value based on the basic driving torque and the first driving torque, and a speed change ratio command value calculation part 32 for calculating a speed change ratio command value based on the basic driving torque and the second driving torque; and an engine and a transmission are controlled based on the engine torque command value and the speed change ratio command value. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

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

Conventionally, Patent Document 1 discloses that an engine rotation speed command value is calculated from a target engine output (target driving force), and an engine torque command value and a gear ratio command value are calculated from the engine rotation speed command value.
JP 2001-047891 A

  However, in the above invention, when the target driving force changes, for example, when the accelerator opening becomes large, the target rotational speed of the engine increases rapidly due to the downshift, and the target driving torque is set large by the inertia torque of the engine. As a result, there is a problem that further downshift occurs, the target drive torque further increases, and the driver feels uncomfortable.

  The present invention has been invented to solve such a problem, and has an object of improving the uncomfortable feeling felt by the driver due to a change in the target driving force.

  In the present invention, target acceleration calculation means for calculating target acceleration from the driving state, feedforward control compensation means for calculating basic drive torque based on the target acceleration, acceleration calculation means for calculating or detecting vehicle acceleration, driving An inertia torque calculation means for estimating the inertia torque from the state, a first drive torque correction value calculation means for calculating a first drive torque correction value based on a deviation between the target acceleration and the acceleration, a deviation between the target acceleration and the acceleration, and inertia Feedback control compensation means having second drive torque correction value calculation means for calculating a second drive torque correction value based on the torque is provided. An engine torque command value calculating means for calculating an engine torque command value based on the basic drive torque and the first drive torque correction value; and a gear ratio for calculating a gear ratio command value based on the basic drive torque and the second drive torque correction value. Command value calculation means having command value calculation means is provided. Then, the engine is controlled based on the engine torque command value, and the transmission is controlled based on the gear ratio command value.

  According to the present invention, when the target driving force changes, for example, when downshifting, the acceleration is set to be large in order to correct the generated inertia torque, so that the inertia torque is further prevented from being generated, and the engine Hunting such as torque can be prevented, and the uncomfortable feeling felt by the driver can be reduced.

  The configuration of the first 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 (engine control means) that controls the engine torque, and a CVT & clutch controller 12 that controls the gear ratio of the CVT 3 and the clutch. (Transmission control means). 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 of the vehicle, a wheel speed sensor 14 for detecting the rotational speed of the wheel, an engine crank An engine rotation speed sensor (crank angle sensor) 15 that is attached to a shaft (not shown) and detects the engine rotation speed; a primary rotation speed sensor 16 that is attached to the primary pulley shaft of the CVT 3 and detects the rotation speed of the primary pulley; , A secondary rotational speed sensor 17 that is attached to the secondary pulley shaft of the CVT 3 and detects the rotational speed of the decanter pulley, and an engine operating point constraint line switching SW 18 that switches whether the operating point of the engine 1 is focused on fuel efficiency or acceleration. Prepare. 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.

  Next, the configuration of an acceleration control system (step S4 to step S12 described later) performed by the drive torque controller 10 will be described with reference to FIG.

  The acceleration control system includes a target acceleration calculation unit 20 (target acceleration calculation means) that calculates a target drive acceleration, and a basic drive torque command value calculation unit 21 that calculates a basic drive torque command value by performing feedforward compensation from the target acceleration. Control compensation means). In addition, a reference acceleration calculation unit 22 that calculates a reference acceleration that is acceleration when there is no inertia torque, an inertia torque estimation unit 24 (inert torque calculation means) that estimates the inertia torque, a first drive torque correction value, and a second drive. A feedback compensation unit 23 (feedback control compensation means) for calculating a torque correction value is provided. Further, a first drive torque correction unit 25 that calculates a first drive torque command value from the basic drive torque and the first drive torque correction value, and a second drive torque command value from the basic drive torque and the second drive torque correction value. A second drive torque correction unit 26; a command value calculation unit 27 (command value calculation unit) that calculates an engine torque command value and a gear ratio command value; and an acceleration estimation unit 28 (acceleration calculation unit) that estimates vehicle acceleration. Have.

  The feedback compensation unit 23 includes a first drive torque correction value calculation unit 29 (first drive torque correction value calculation means) that calculates a first drive torque from the reference acceleration and the vehicle acceleration, and the reference acceleration, vehicle acceleration, and inertia torque. A second drive torque correction value calculation unit 30 (second drive torque correction value calculation means) that calculates the second drive torque correction value from the correction value is provided.

  The command value calculation unit 27 includes an engine torque command value calculation unit 31 (engine torque command value calculation unit) that calculates an engine torque command value, and a gear ratio command value calculation unit 32 (speed ratio command value) that calculates a gear ratio command value. Computing means).

  Reference numeral 40 denotes the engine 1 and CVT 3 to be controlled.

  Next, the processing content of the drive torque controller 10 will be described with reference to the flowchart of FIG. 3 and the block diagram 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 V _w of the drive wheel is calculated from the reciprocal of the wheel speed pulse width (for 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. Calculate.

In step S 3, 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 S4, it calculates the acceleration estimated value alpha _wf performs arithmetic processing by the acceleration estimation bandpass filter by: a wheel speed V _w calculated in step S2 by the acceleration estimating unit 28 as an input. In an actual calculation, calculation is performed using a recurrence formula obtained by discretization by Tustin approximation or the like.

However, s: Laplace operator, ζ _n : damping rate, ω _n : natural angular frequency, and ζ _n and ω _n are determined according to the wheel speed noise level.

In step S5, the target acceleration calculator 20 calculates a target acceleration α _w ^* based on the accelerator opening A _po and the wheel speed V _w . The target acceleration α _w ^* is read from the map shown in FIG. FIG. 5 is a map showing the target acceleration α _w ^* with respect to the accelerator opening A _po and the wheel speed V _w . As the accelerator opening A _po increases, the target acceleration / deceleration α _w ^* increases and the wheel speed V _w decreases. Then, the target acceleration α _w ^* becomes smaller. The target drive torque may be calculated instead of the target acceleration α _w ^* .

In step S6, the basic drive torque command value calculation unit 21 performs feedforward control on the target acceleration α _w ^* by the filter process shown in the equation (2), performs phase compensation, and performs the phase that is the basic drive torque command value. Compensation output _Tff is calculated. In an actual calculation, calculation is performed using a recurrence formula obtained by discretization by Tustin approximation or the like.

In step S7, in the reference acceleration calculation unit 22, the delay compensation G _ref (s) corresponding to the acceleration reference model response to the target acceleration α _w ^* and the delay compensation G corresponding to the acceleration estimation band-pass filter are calculated by the equation (3). _{Applying lp} (s) (second-order lag model), a reference acceleration α _{w — ref} for comparing the acceleration estimated values α _wf is calculated.

In step 8, the addition unit 41 converts the acceleration deviation α _err to α _err = α _{w — ref} −α _wf (4)
The first driving torque correction value T _fb1 is calculated by the first driving torque correction value calculation unit 29 of the feedback compensation unit 23 according to the equation (5).

However, K _{P1 is} the first proportional gain, and K _{I1 is} the first integral gain. The first driving torque correction value T _fb1 is calculated from the acceleration deviation α _err that does not correct the inertia torque.

In step S9, the inertia torque estimation unit 24 calculates the drive wheel angular speed ω _w (ω _w = wheel speed V _w / tire radius R) and the gear ratio change rate (differential value) (d / dt) I.
T _{i — est} = J _e × ω _w × I _p × I _f2 × (d / dt) I Equation (6)
However, the inertia torque estimation value T _{i — est} is calculated based on J _e : engine to primary pulley inertia moment, _If : final reduction ratio. Note that the gear ratio change rate is calculated by, for example, a high-pass filter shown in Expression (7).

Where T _{H is a} first-order lag time constant for a high-pass filter. Actually, it is calculated using a recurrence formula obtained by discretization by Tustin approximation or the like. In equation (6), a gear ratio command value I _p ^* described later may be used instead of the actual gear ratio I _p . By using the speed ratio command value I _p ^*, it is possible to set the first-order delay time constant T _H of the high-pass filter transfer characteristic G _CVT (s) corresponding to the gear ratio control, it can be estimated more accurately inertia torque Can do.

In step S10, first, the subtraction unit 42 _{calculates the} acceleration deviation α _err and the acceleration α _Ti generated by the inertia torque,
α _err '= α _err -α _Ti formula (8)
α _Ti = T _{i — est} / (M × R) Equation (9)
To calculate the corrected acceleration deviation α _err ′.

Next, in the integral term calculation unit 43 of the second drive torque correction unit 30 of the feedback compensation unit 23, the acceleration deviation α _err is input,
T _fbI2 (s) / α _err = K _I2 / s Equation (10)
_Is calculated from the integral term T _fbI2 , and the proportional term calculation unit 44 _receives the corrected acceleration deviation α _err ′ as input.
T _fbP2 (s) / α _err '= K _P2 formula (11)
_{Is used} to calculate the proportional term T _fbP2 . However, K _{I2 is} the second integral gain, and K _{P2 is} the second proportional gain. The values of the first integral gain and the second integral gain are equal (K _I1 = K _I2 ), and the first proportional gain and the second proportional gain are equal to or greater than the second proportional gain (K _P1 ≧ K _P2 ). To do. Here, using the acceleration alpha _err 'obtained by correcting the inertia torque proportional term, the integral term using acceleration alpha _err of formula (4), by equalizing the first integral gain and a second integral gain, steady Sometimes the engine operating point of the engine can be the optimum fuel efficiency operating point.

Then, the adding unit 45 adds the integral term T _fbI2 and the proportional term T _fbP2 calculated by the equations (10) and (11),
T _fb2 = T _fbI2 + T _fbP2 formula (12)
Thus, the second drive torque correction value T _fb2 is calculated.

  Through the above steps, the first driving torque correction value that is not corrected for inertia torque caused by the change in acceleration and the second driving torque correction value that is corrected for inertia torque are calculated.

In step S11, the first drive torque correction unit 25 calculates the first drive torque command value T _Te ^* from the phase compensation output T _ff calculated in step S6 and the first drive torque correction value T _fb1 calculated in step S8.
T _Te ^* = T _ff + T _fb1 Formula (13)
Calculate by In the second drive torque correction unit 26, the second drive torque command value T _IP ^* is calculated from the phase compensation output T _ff calculated in step 6 and the second drive torque correction value T _fb2 calculated in step S11.
T _Ip ^* = T _ff + T _fb2 formula (14)
Calculate by

In step S12, from the second drive torque command value T _Ip ^* and the drive wheel angular velocity ω _w ,
L _Ip ^* = T _Ip ^* × ω _w formula (15)
Thus, the second output command value L _Ip ^* is calculated, and the target primary rotational speed ω _p ^* which is the optimum fuel consumption operating point is read from the map shown in FIG. 6 stored in advance in the memory. FIG. 6 is a diagram showing the relationship between the equal output line (drive torque × drive wheel angular velocity), the engine operating point constraint line, the primary rotational speed ω _p ^*, and the engine torque. From the intersection of the equal output line and the engine operating point constraint line Read the target primary rotational speed ω _p ^* . The engine operating point constraint line indicates an optimal fuel efficiency driving line in which fuel efficiency is emphasized when the engine torque is positive, that is, when traveling at constant speed or acceleration. When the engine torque is a negative value, an engine brake characteristic line is shown. In FIG. 6, the engine operating point constraint line is indicated by a solid line, the equal output line is indicated by a broken line, and the equal fuel 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 S13, from the target primary rotation speed ω _p ^* calculated in step S13 in the gear ratio command value calculation unit 32 of the command value calculation unit 27,
I _p ^* = ω _p ^* / ω _s formula (16)
Based on the above, the gear ratio command value I _p ^* is calculated. The shift command value I _p ^* is a command value corrected by the second drive torque correction value T _fb2 corrected for inertia torque, and the gear ratio command value I _p ^* is a command value that is not affected by inertia torque.

In step S14, the engine torque command value calculation unit 31 of the command value calculation unit 27 calculates the first drive torque command value T _Te ^* and the actual gear ratio I _{p of} CVT3,
T _e ^* = T _Te ^* / (I _p × I _f ) Equation (17)
Based on this, the final engine torque command value _Te ^* is calculated. ^* The final engine torque command value T _e is corrected command value by the first drive torque correction value T _fb1 not corrected inertia torque.

In step S15, 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. ^* final engine torque command value T _e of the engine torque, and controls the speed change ratio command value I _p ^* the gear ratio of the primary pulley 4 and secondary pulley 5 of CVT 3 (step S15 constitutes the control means).

  When the acceleration changes due to the above control, the gear ratio command value is a command value excluding the inertia torque, so that the gear ratio is not downshifted by the inertia torque. It is possible to prevent the occurrence of inertia torque newly generated by downshifting. In addition, the final engine torque command value is a command value that takes into account inertia torque, and outputs engine torque that follows vehicle driving conditions (acceleration, gradient driving, etc.) to make the driver feel uncomfortable. You can drive without. As a result, no inertia torque is newly generated, and no deviation is accumulated in the integral term of the feedback compensation unit 23 that performs the PI control. Therefore, the engine torque can follow the command value without causing hunting.

  Next, changes in acceleration and the like when the accelerator is depressed by the driver will be described with reference to time charts shown in FIGS. 7 and 8 when the present invention is not used and when it is used. FIG. 7 is a diagram showing changes in driving torque and the like when the accelerator opening is opened without using the present invention, and FIG. 8 is a diagram showing changes in driving torque and the like when the present invention is used.

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

At time t1, the accelerator opening is changed from A _po1 to A _po2. As a result, the gear ratio, engine torque, and drive torque command values increase with the accelerator opening. However, a mechanical delay with respect to the command value occurs in the actual gear ratio and changes in engine torque. Here, the time when the actual gear ratio and the like start changing is assumed to be time t2.

  At time t2, the actual gear ratio or the actual engine torque changes after a mechanical delay with respect to the command value occurs. Here, a downshift is caused by an increase in the accelerator opening, but an inertia torque of the engine occurs with the downshift. When feedback control is being performed, the inertia deviation (decrease) is regarded as a disturbance and compensated accordingly, so correction is made in the direction in which the engine torque increases to compensate for the acceleration deviation. As a result, the gear ratio is further downshifted and a new inertia torque is generated. As the engine speed increases gradually and the vehicle speed increases, the increase in inertia torque decreases. Thereafter, the inertia torque begins to decrease, and the inertia torque disappears at time t3. As the inertia torque decreases, the gear ratio command value and the engine torque command value also decrease.

  At time t3, the inertia torque disappears, but the rise of the actual acceleration (measured value in the figure) is delayed although the engine torque command value is increased in order to compensate for the deviation of the acceleration due to the inertia torque, and the target acceleration value And the deviation of the measured value is accumulated in the integrator. When the inertia torque is lost, the acceleration increases (the vehicle accelerates) due to the accumulated torque increase. For this reason, the engine torque command value decreases to reduce the acceleration, but the actual engine torque reacts with a delay, so that the decrease command amount of the engine torque command value is now stored in the integrator. Due to the above delay, the acceleration hunts by repeatedly overshooting and undershooting the acceleration reference value.

  This hunting gradually converges, and at time t4, the engine torque command value matches the actual engine torque, and the acceleration also matches the acceleration reference value.

Next, the case of using the present invention will be described with reference to FIG. Before time t1, the vehicle travels in a state where the accelerator opening A _po1 , the gear ratio Ip1, the engine torque Te1, the driving torque Td1, the accelerator opening is constant, and the driving torque is balanced with the running resistance, that is, the vehicle speed is constant. ing.

Accelerator opening is changed from A _po1 to A _po2 at time t1 '. A downshift is caused by this accelerator opening change, and inertia torque is generated along with the downshift. Therefore, in the present invention, the generated inertia torque is estimated, and a first drive torque command value for calculating the engine torque command value; A second drive torque command value for calculating the gear ratio, that is, the engine speed is calculated (step S12). Here, the inertia torque is not corrected for the first drive torque command value, but is corrected only for the second drive torque command value. That is, the first drive torque command value is subjected to calculation including the influence of inertia torque (the change in the drive torque command value in FIG. 8 indicates the change), but the second drive torque command value is Calculation is performed without the influence of inertia torque (the solid line indicates the change in the drive torque command value change in FIG. 8). As a result, the engine torque command value calculated from the first drive torque command value becomes a command value affected by the inertia torque, and the gear ratio command value calculated from the second drive torque command value is influenced by the inertia torque. It is a command value excluding. And each command value increases from time t1 '. However, a mechanical delay with respect to the command value occurs in the actual gear ratio and changes in engine torque. Here, the time when the actual gear ratio and the like start to change is defined as time t2 ′.

  At time t2 ', the actual engine torque and the actual gear ratio start to change. Further, inertia torque is generated in accordance with the change in the actual engine torque, but in the present invention, since the gear ratio command value is a command value excluding the influence of inertia torque, a new downshift due to inertia torque is not generated, There will be no further inertia due to the new downshift. As a result, the inertia torque associated with the downshift can be reduced. The engine torque command value calculated from the first drive torque command value temporarily increases because it includes the inertia torque generated by the downshift, but thereafter gradually decreases because no downshift due to the inertia torque occurs. . Thereafter, the inertia torque starts to decrease as the engine speed increases, and the inertia torque disappears at time t3 '. In the present invention, since no new inertia torque is generated, the time t3 'at which the inertia torque does not exist can be shortened. Since the gear ratio is not affected by the inertia torque, the actual gear ratio changes following the command value.

  At time t3 ', the inertia torque disappears and the vehicle acceleration increases. In the present invention, since a new inertia torque does not occur, no deviation is accumulated in the integrator, and changes following the acceleration reference value without causing hunting.

  At time t4 ', the engine torque command value matches the actual engine torque, and the acceleration also matches the acceleration reference value.

  As described above, in the present invention, when the accelerator opening is increased, the estimated ratio of the inertia ratio is subtracted from the estimated ratio of the transmission ratio, thereby eliminating the newly generated inertia torque and reducing the transmission ratio command value (FIG. 8). The hatched portion can be prevented, and hunting can be prevented.

  Further, a case where the present invention is not used when the vehicle is traveling on an uphill after traveling on a flat road, and a change in driving torque when the vehicle is used will be described with reference to time charts shown in FIGS. FIG. 9 is a diagram showing changes in acceleration and the like when the driver increases the accelerator opening without using the present invention, and FIG. 10 is a diagram showing changes in acceleration and the like when the present invention is used. .

  First, a case where the present invention is not used will be described with reference to FIG. The accelerator opening is constant. Before the time t1, the vehicle travels on a flat road without a gradient, and the climbing gradient is reached at the time t1. The gradient is constant.

  At time t1, since the acceleration decreases when the climbing slope is reached, the drive torque and the engine torque are increased, the gear ratio is downshifted, and the command is issued so that the acceleration is zero, that is, the speed is constant. However, a mechanical delay with respect to the command value occurs in the actual gear ratio and changes in engine torque. Here, the time when the actual gear ratio and the like start changing is assumed to be time t2.

  At time t2, the actual engine torque and the actual gear ratio increase due to the downshift in order to compensate for the acceleration reduced by the gradient, but an inertia torque occurs due to the downshift. When feedback control is being performed, the inertia deviation (decrease) is regarded as a disturbance and compensated accordingly, so correction is made in the direction in which the engine torque increases to compensate for the acceleration deviation. As a result, the gear ratio is further downshifted and a new inertia torque is generated. As the engine speed gradually increases, the increase in inertia torque decreases, and then the inertia torque starts to decrease. That is, the vehicle decelerates due to the increase of the inertia torque, and then accelerates due to the decrease of the inertia torque. As the inertia torque decreases, the gear ratio command value and the engine torque command value also decrease.

  However, although the vehicle accelerates due to the decrease in inertia torque, the engine acceleration command value is increased to compensate for the acceleration deviation due to inertia torque, but the actual acceleration rise is delayed, and the target value and measured value of acceleration are delayed. When the inertia torque becomes smaller, the acceleration increases due to the accumulated engine torque. For this reason, the engine torque command value decreases to reduce the acceleration, but the actual engine torque reacts with a delay, so that the decrease command amount of the engine torque command value is now stored in the integrator. Due to the above delay, the acceleration hunts by repeatedly overshooting and undershooting the acceleration reference value.

  This hunting gradually converges, and at time t3, the engine torque command value matches the actual engine torque, and the acceleration also matches the acceleration reference value.

  Next, the case of using the present invention will be described with reference to FIG. The accelerator opening is constant. Before the time t1, the vehicle travels on a flat road without a gradient, and the climbing gradient is reached at the time t1. The gradient is constant.

  At time t1, since the acceleration decreases when the climbing slope is reached, the drive torque and the engine torque are increased, the gear ratio is downshifted, and the command is issued so that the acceleration is zero, that is, the speed is constant. In the present invention, the generated inertia torque is estimated, and the first drive torque command value for calculating the engine torque command value and the second drive torque command value for calculating the speed ratio, that is, the engine speed, are calculated. (Step S12). Here, the inertia torque is not corrected for the first drive torque command value, but is corrected only for the second drive torque command value. That is, the first drive torque command value is calculated including the influence of inertia torque (the change in the drive torque command value in FIG. 10 indicates the change), but the second drive torque command value is Calculation is performed without the influence of inertia torque (the solid line indicates the change in the drive torque command value change in FIG. 10). As a result, the engine torque command value calculated from the first drive torque command value becomes a command value affected by the inertia torque, and the gear ratio command value calculated from the second drive torque command value is influenced by the inertia torque. It is a command value excluding. And each command value increases from time t1. However, a mechanical delay with respect to the command value occurs in the actual gear ratio and changes in engine torque. Here, the time at which the actual gear ratio and the like start changing is referred to as time t2 '.

  At time t2 ', the actual engine torque and the actual gear ratio start to change. In addition, inertia torque is generated as the actual engine torque changes. In the present invention, the gear ratio command value estimates the inertia torque and is a command value that excludes the influence of inertia torque. No shift occurs and no further inertia shift occurs due to a new downshift. As a result, the inertia torque associated with the downshift can be reduced. The engine torque command value calculated from the first drive torque command value temporarily increases because it includes the inertia torque generated by the downshift, but thereafter gradually decreases because no downshift due to the inertia torque occurs. . Thereafter, the inertia torque starts to decrease as the engine speed increases, and the inertia torque disappears at time t3 '. In the present invention, since no new inertia torque is generated, the time t3 'at which the inertia torque does not exist can be shortened. Since the second proportional gain is smaller than the first proportional gain, the second drive torque command value, that is, the gear ratio command value has a large output from the integral term and changes more slowly than the engine torque command value. To do. As a result, the gear ratio does not change suddenly when the accelerator opening is constant, and the driver feels uncomfortable. Further, in the present invention, since no new inertia torque is generated, no deviation is accumulated in the integrator, so that it changes following the acceleration reference value without causing hunting.

  At t3 ', there is no inertia torque and no hunting occurs, so the acceleration is 0, that is, constant speed running.

At t4 ′, the first integral gain (K _I1 ) and the second integral gain (K _I2 ) are set to the same value, so that the engine torque command value and the gear ratio command value match, and the engine operating point is It can be set as the fuel efficiency optimum driving point.

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

  In the present invention, in a two-degree-of-freedom control system including a feedforward compensation unit and a feedback compensation unit, a first drive torque computing unit that computes an engine torque command value in the feedback compensation unit, and a second that computes a gear ratio command value A drive torque correction unit is provided, and the gear ratio command value is corrected without the influence of inertia torque. As a result, there is no further downshift due to the inertia torque generated by the downshift, and no new inertia torque is generated. Therefore, the inertia torque can be reduced and the shift time can be shortened. Further, even when the feedback compensation unit has an integral term, acceleration deviation due to downshift is not accumulated, and hunting can be prevented. Therefore, it is possible to reduce the uncomfortable feeling that the driver feels at the time of shifting (particularly during downshifting).

  Since the first proportional gain is set to a large value for the second proportional gain and the first integral gain and the second integral gain are made equal, the gear ratio command value is calculated when a high-frequency component other than inertia torque occurs in the acceleration deviation. 2 The influence on the drive torque correction value can be reduced, and a new inertia torque can be prevented from occurring. Further, when the acceleration deviation is 0, that is, in the steady state, the first drive torque correction value and the second drive torque correction value match, so that the engine operating point is set as the optimum fuel consumption point shown in FIG. 6 in the steady state. be able to.

  A second embodiment of the present invention will be described. In this embodiment, the mechanical configuration of the first embodiment is the same, and the configuration of the acceleration control system performed by the drive torque control controller 10 is different. The configuration will be described with reference to FIG.

  In addition to the acceleration control system of the first embodiment, the acceleration control system of this embodiment includes an inertia torque correction unit 33 (inert torque correction means) that corrects the inertia torque estimated by the inertia torque estimation unit 24, and a command. An engine torque command value correction unit 34 for correcting the engine torque command value calculated by the value calculation unit 27 is provided. With this configuration, the driver corrects the engine torque command value based on the estimated value of the inertia torque, and further obtains the second drive torque to be used for the CVT 3 based on the value obtained by correcting the estimated value of the inertia torque. You can feel less discomfort.

  Next, the processing content of the drive torque controller 10 will be described with reference to the flowchart of FIG. 12 and the block diagram of FIG. The flowchart of FIG. 12 is performed every predetermined time, for example, every 10 msec.

  Since the control from step S1 to step 9 is the same as the control of the first embodiment, the description thereof is omitted here.

In step S10, the inertia torque estimation value correction unit 33 performs the inertia torque estimation value T _{i — est} calculated in step S9.
T _{i — est} '= K _Ti × T _{i — est} formula (18)
Then, the final inertia torque estimate T _{i — est} ′ that actually affects the acceleration as a disturbance is calculated. K _{Ti is an} inertia torque correction coefficient, and is calculated from an engine torque command value _Te ^* described later. The inertia torque correction coefficient K _Ti is calculated from the map shown in FIG. Figure 14 is a map showing a relationship between the engine torque and inertia torque correction coefficient, the engine torque command value T _e ^* maximum inertia torque correction coefficient when the (_ _max limit T _e) by up (K _Ti = 1) When the engine torque is reduced, the inertia torque correction coefficient is also reduced, and the inertia torque correction coefficient is a constant value (K _{Ti — min} ) below a predetermined engine torque command value. This is because the inertia torque is corrected in a feed-forward manner by the first drive torque correction unit 25 in step 12 (step S11 in the first embodiment) in a low load state where the increase in acceleration is small. Because there is no. Therefore, the inertia torque correction coefficient is decreased in a low load state, and the inertia torque correction coefficient is increased in a high load state where the increase in acceleration is large, so that the inertia torque is accurately estimated.

In step S11, the same control as in step S10 of the first embodiment is performed, but the final inertia torque estimation value T _{i — est} ′ is used instead of the inertia torque estimation value used in step S10.

Since the control from step S12 to step S15 is the same control as from step S11 to step S14 of the first embodiment, the description thereof is omitted here. In step S14 of the first embodiment, the final engine torque command value _Te ^* is used. However, in step S15 of the second embodiment, the engine torque command value _Te ^* is used.

In step S16, the engine torque command value correction unit 34 calculates the inertia torque estimated value T _{i — est} calculated in step S9 and the engine torque command value T _e ^* calculated in step S15 (the expression of step S14 in the first embodiment ( 17))
T _e ^* ′ = T _e ^* + T _{i — est} / (I _p × I _f ) Equation (19)
Based on this, the final engine torque command value _Te ^* 'is calculated. As a result, the amount of engine torque increased by the inertia torque can be corrected, and a more accurate engine torque command value can be calculated.

In step S17, 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 final 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.

  With the above control, it is possible to estimate the inertia torque more accurately by correcting the inertia torque estimation value, and the final engine torque command value is a value obtained by adding the increase in the engine torque due to the inertia torque. Command value can be calculated.

  The effect of 2nd Embodiment of this invention is demonstrated.

  In this embodiment, in addition to the effects of the first embodiment, the inertia torque estimated by the inertia torque estimation unit 24 is corrected by the inertia torque correction unit 33. If the inertia torque is large, the inertia torque correction coefficient is increased, When the inertia torque is small, the inertia torque can be estimated with high accuracy by reducing the inertia torque correction coefficient, and the driver can feel less uncomfortable.

  In addition, since the torque increase due to the inertia torque estimated by the engine torque command value correction unit 34 is added to the engine torque command value, the final engine torque command value can be calculated more accurately, and the final torque after correcting the inertia torque is corrected. Since the torque of the engine 1 is controlled by the engine torque command value, the engine torque can be made to quickly follow the actual change required even when the gear ratio such as a downshift changes.

  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 equipped with automatic engines.

It is a schematic block diagram of this invention. It is a block diagram which shows the acceleration control system of the drive torque control controller of 1st Embodiment of this invention. It is a flowchart which the drive torque control controller of 1st Embodiment of this invention performs. It is a block diagram which shows the acceleration control system of 1st Embodiment of this invention. It is a map which calculates the target acceleration of this invention. It is a map which calculates the rotational speed of the target primary pulley of this invention. 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. It is a time chart when driving on a slope road when the present invention is not used. It is a time chart when drive | working on a slope road in the case of using this invention. It is a block diagram which shows the acceleration control system of the drive torque control controller of 2nd Embodiment of this invention. It is a flowchart which the drive torque control controller of 2nd Embodiment of this invention performs. It is a block diagram which shows the acceleration control system of 2nd Embodiment of this invention. It is a map which calculates the inertia torque correction coefficient of this 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 (engine control means)
12 CVT & clutch controller (transmission control means)
20 Target acceleration calculation unit (target acceleration calculation means)
21 Basic drive torque command value calculation unit (feed forward control compensation means)
23 Feedback Compensation Unit (Feedback Control Compensation Unit)
24 Inert torque estimation section (inert torque calculation means)
27 Command value calculation unit (command value calculation means)
28 Acceleration estimation unit (acceleration calculation means)
29 first driving torque correction value calculation unit (first driving torque correction value calculation means)
30 Second driving torque correction value calculation unit (second driving torque correction value calculation means)
31 Engine torque command value calculation unit (engine torque command value calculation means)
32 Gear ratio command value calculation unit (speed ratio command value calculation means)
33 Inert shuttle correction (inert shuttle correction means)

Claims (5)

Target acceleration calculating means for calculating the target acceleration from the driving state;
Feedforward control compensation means for calculating a basic drive torque based on the target acceleration;
Acceleration calculation means for calculating or detecting vehicle acceleration;
An inertia torque calculation means for estimating the inertia torque from the driving state;
First driving torque correction value calculating means for calculating a first driving torque correction value based on the target acceleration and the deviation of the acceleration; and a second driving torque correction value based on the target acceleration, the deviation of the acceleration and the inertia torque. Feedback control compensation means having second drive torque correction value calculation means for calculating;
Engine torque command value calculation means for calculating an engine torque command value based on the basic drive torque and the first drive torque correction value; and a gear ratio command value based on the basic drive torque and the second drive torque correction value. Command value calculating means having gear ratio command value calculating means;
Engine control means for controlling the engine based on the engine torque command value;
A driving force control apparatus comprising: a transmission control unit that controls the transmission based on the transmission ratio command value.   2. The driving force control apparatus according to claim 1, wherein feedback gains of the first driving torque correction value calculation unit and the second driving torque correction value calculation unit are set to different values. The first drive torque correction value calculation means and the second drive torque correction value calculation means perform proportional control and integral control,
The proportional gain of the first driving torque correction calculating means is larger than the proportional gain of the second driving torque correction calculating means;
3. The driving force control apparatus according to claim 2, wherein an integral gain of the first drive torque correction calculation means is equal to an integral gain of the second drive torque correction calculation means.   4. The driving force according to claim 3, wherein the proportional gain of the second driving torque correcting unit is calculated based on a value obtained by subtracting a deviation of acceleration due to the inertia torque from the deviation of the target acceleration and the acceleration. Control device. An inertia torque correction means for correcting the inertia torque calculated by the inertia torque calculation means based on the engine torque command value;
The inertia torque correction means calculates a correction value by multiplying the inertia torque by 1 when the engine torque command value is an upper limit value of the engine torque,
5. The correction value is calculated by dividing the inertia torque by a value smaller than 1 when the engine torque command value is smaller than an upper limit value of the engine torque. The driving force control device according to one.

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