JP2007064180A - Control device for vehicle driving force - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control device for vehicle driving force by which a demanded driving force is generated to offer satisfactory acceleration-characteristics upon a driver's demand for acceleration. <P>SOLUTION: The control device for driving force executes the program comprising the following steps. An accelerator stroke is detected (S100), an estimate G is computed (S110), and a reference throttle opening is computed (S120). Throttle adjustment is made (S130). In the case of a power-on down-shift, a post-shift synchronized NT is selected as an operational NT (S140). A reference engine-torque is computed by a torque-converter linkage diagram on the basis of the operational NT and the reference throttle opening (S150). Demanded engine-torque is computed from the reference engine torque (S170). Demanded engine-speed is computed from the operational NT and the reference engine-torque by a torque-converter characteristic diagram (S180). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a control device for a vehicle on which a power train having an engine and an automatic transmission is mounted, and more particularly to a driving force control device capable of outputting a driving force corresponding to a driver's required driving force.

  In a vehicle equipped with an engine and an automatic transmission that can control engine output torque independently of the driver's accelerator pedal operation, it is calculated based on the driver's accelerator pedal operation amount, vehicle driving conditions, etc. Furthermore, there is a concept of “driving force control” that realizes a positive and negative target driving torque by an engine torque and a transmission gear ratio of an automatic transmission. In addition, control methods called “driving force request type”, “driving force demand type”, “torque demand method”, and the like are similar to this.

  The torque demand type engine control device calculates a target torque of the engine based on the accelerator operation amount, the engine speed, and the external load, and controls the fuel injection amount and the supply air amount according to the target torque.

  In such a torque demand type engine control device, the actual output is calculated by adding a loss load torque such as friction torque that is lost in the engine or power train system to the required output torque, and calculating it as the target generated torque. Thus, the fuel injection amount and the supply air amount are controlled.

  According to this torque demand type engine control device, by using the engine torque, which is a physical quantity directly acting on the control of the vehicle, as the reference value of the control, it is possible to improve the drivability, such as maintaining a constant steering feeling. Can do.

  Japanese Patent Application Laid-Open No. 10-325348 (Patent Document 1) discloses an engine idle speed control device using such a torque demand system. The engine idle speed control device disclosed in this publication includes an engine speed detection means for detecting an actual engine speed, a target torque calculation means for calculating a target torque to be generated by the engine, and an intake air amount. An intake air amount control means for controlling to a desired control target amount, a control target amount calculation means for calculating a control target amount to be given to the intake air amount control means based on at least the actual engine speed and the target torque, and a predetermined idle An idle speed control means for performing feedback control so that the actual engine speed becomes a predetermined target idle speed in the state, and an engine that is input to the control target amount calculation means during the feedback control by the idle speed control means Switching means for providing a target idle speed instead of the actual engine speed as a rotational speed parameter That.

According to the engine idling speed control device, in a normal driving state, the target torque calculating means sets the target torque in response to a driver's request for accelerator operation, friction loss, and the like. Based on the actual engine speed detected by the engine speed detecting means and the target torque, the control target amount of the intake air amount is obtained, and the intake air amount is controlled by the intake air amount control means including a throttle valve. Be controlled. The fuel injection amount is also given according to the target torque. On the other hand, during idle operation, feedback control is performed by the idle speed control means so that the actual engine speed approaches the target idle speed. During the idle control (during feedback control), the control target amount calculation means for calculating the control target amount for the intake air amount control means is changed to the actual engine speed as the engine speed parameter via the switching means. Instead, the target idle speed is input. Thus, for example, even when the load increases as a disturbance and the actual engine speed decreases, the control target amount of the intake air amount does not decrease accordingly, and the required intake air amount at the idle target rotation number does not decrease. Will be secured. As a result, in the idle control state, for example, even when the load increases as some disturbance and the actual engine speed decreases, the target throttle opening does not decrease with this, and the target idle speed The amount of intake air necessary for maintenance is secured. Therefore, stable idle control is possible.
Japanese Patent Laid-Open No. 10-325348

  However, when accelerating in the normal operation state of the engine idle speed control device disclosed in this publication, the target torque calculation means performs the target torque according to the driver's request for acceleration operation, friction loss, etc. Is set, and the control target amount of the intake air amount is obtained based on the actual engine speed and the target torque detected by the engine speed detecting means. That is, the engine is controlled based on the actual engine speed.

  When such acceleration processing is executed in a vehicle equipped with an automatic transmission equipped with a torque converter with a driving force demand method, the actual engine speed is used, so that the required torque that compensates for the dynamic transient delay cannot be calculated. This is because, in the torque demand method using the actual engine speed, a control system in which the dynamic delay is not compensated in the first place. Furthermore, in a closed loop feedback control system that detects the actual engine speed and eliminates the deviation from the target value, the control system becomes unstable (divergence or vibration) due to feedback delay due to the frequency characteristics of the transmission system. Sometimes.

  As a result, if the engine is controlled by the torque demand method using the actual engine speed disclosed in the above-mentioned publication, sufficient dynamic performance during acceleration cannot be expressed, and the vehicle feels delayed in acceleration. , A lack of acceleration may occur.

  The present invention has been made in order to solve the above-described problems, and its purpose is to generate the required driving force when the driver requests acceleration, and to exhibit good acceleration characteristics. A driving force control apparatus for a vehicle is provided.

  A driving force control apparatus according to a first aspect of the present invention controls the driving force of a vehicle equipped with a power train that includes an engine and a transmission connected to the engine via a torque converter. The control device includes target torque setting means for setting a target engine torque of the engine, and control means for controlling the engine based on the target engine torque output from the target torque setting means. The target torque setting means includes means for setting the target engine torque based on the throttle opening of the engine and the turbine speed of the torque converter.

  According to the first aspect, due to the presence of the torque converter, the change speed of the turbine speed becomes slower than the change speed of the engine speed. This is because the turbine rotational speed itself is governed by the transmission gear ratio and the transmission output shaft rotational speed. In the case of such transient characteristics, the target engine torque is set based on the turbine speed of the torque converter instead of using the detected current engine speed. For this reason, since a closed-loop feedback control system that controls the engine speed is not configured, it is possible to prevent the control system from becoming unstable (divergence or vibration) due to feedback delay due to the frequency characteristics of the transmission system. . Furthermore, when calculating the target engine torque during the shift process, if the target engine torque is calculated using the synchronized turbine speed after the shift, the target engine torque is calculated in anticipation of a transient delay in the turbine speed. Since it is possible, the transient delay can be eliminated. As a result, it is possible to provide a vehicle driving force control device that can generate the required driving force and exhibit good acceleration characteristics when the driver requests acceleration.

  In the driving force control apparatus according to the second invention, in addition to the configuration of the first invention, the target torque setting means takes into account the engine performance and the characteristics of the torque converter, and uses the throttle opening as a parameter for the turbine. Means for calculating the target engine torque based on information defining the relationship between the rotational speed and the turbine torque is included.

  According to the second invention, it is possible to calculate the turbine torque from the turbine rotational speed using the torque converter coupling diagram that defines the relationship between the turbine rotational speed and the turbine torque, and convert the turbine torque into the target engine torque. Can be calculated. Since the turbine speed is used instead of the detected current engine speed, the control can be stabilized and the response can be improved.

  In the driving force control apparatus according to the third aspect of the invention, in addition to the configuration of the first aspect, the target torque setting means takes into account the engine performance and the characteristics of the torque converter, and uses the throttle opening as a parameter as a turbine. Means for calculating the target engine torque based on a map defining the relationship between the rotational speed and the turbine torque is included.

  According to the third invention, the turbine torque can be calculated from the turbine rotational speed using the map which is a torque converter coupling diagram that defines the relationship between the turbine rotational speed and the turbine torque, and the turbine torque is converted. A target engine torque can be calculated. Since the turbine speed is used instead of the detected current engine speed, the control can be stabilized and the response can be improved.

  According to a fourth aspect of the present invention, there is provided a driving force control apparatus, in addition to the second or third aspect of the invention, means for detecting the shift state of the transmission and means for detecting the accelerator operation state of the driver. And further including. The target torque setting means determines a turbine speed used for calculating the target engine torque based on the shift state and the accelerator operation state, and uses the turbine torque calculated using the determined turbine speed. Means for calculating the target engine torque.

  According to the fourth aspect of the invention, for example, in a power-on downshift in which the accelerator pedal is depressed to downshift, the turbine rotational speed synchronized after the gear shift is the turbine rotational speed used for calculating the target engine torque. decide. In this way, when calculating the target engine torque, the synchronized turbine rotational speed after the shift is used, so that a transient delay of the target engine torque during the shift control can be avoided.

  In the driving force control apparatus according to the fifth aspect of the invention, in addition to the configuration of the fourth aspect of the invention, the target torque setting means determines the synchronous turbine rotational speed after the shift when the shift state is a power-on downshift shift. Means for calculating a target engine torque using the turbine torque calculated by using the turbine torque is included.

  According to the fifth aspect of the present invention, in the power-on downshift, the turbine speed synchronized after the shift is determined to be the turbine speed used for calculating the target engine torque. In this way, when calculating the target engine torque, the synchronized turbine rotational speed after the shift is used, so that a transient delay of the target engine torque during the shift control can be avoided.

  In the driving force control apparatus according to the sixth aspect of the invention, in addition to the configuration of the fourth aspect of the invention, the target torque setting means uses the synchronous turbine speed after the shift when the shift state is an off-upshift shift. Means for calculating a target engine torque using the turbine torque calculated in the above.

  According to the sixth aspect of the invention, in the off-up shift in which the accelerator pedal is off and the up-shift is performed, the turbine rotational speed synchronized after the shift is determined to be the turbine rotational speed used for calculating the target engine torque. In this way, when calculating the target engine torque, the synchronized turbine rotational speed after the shift is used, so that a transient delay of the target engine torque during the shift control can be avoided.

  In addition to the configuration of the second or third invention, the driving force control device according to the seventh invention detects means for detecting the state of the one-way clutch of the transmission and the accelerator operation state of the driver. Means for further comprising. The target torque setting means determines the turbine rotational speed used for calculating the target engine torque based on the state of the one-way clutch and the accelerator operation state, and calculates the turbine torque calculated using the determined turbine rotational speed. And means for calculating the target engine torque.

  According to the seventh invention, for example, if there is a (re) acceleration request when the one-way clutch (one-way clutch) is in the non-driven state, a delay time occurs until the one-way clutch is in the driven state. In such a case, it is determined that the turbine rotational speed synchronized after the gear shift (after the gear shift where the one-way clutch is changed from the non-driving state to the driving state) is the turbine rotational speed used for calculating the target engine torque. In this way, when calculating the target engine torque, the synchronized turbine rotational speed after the shift is used, so that a transient delay of the target engine torque during the shift control can be avoided.

  In the driving force control apparatus according to the eighth aspect of the invention, in addition to the configuration of the seventh aspect, the target torque setting means is configured such that the one-way clutch is in the re-acceleration from the non-driving state, Means for calculating the target engine torque using the turbine torque calculated using the rotational speed is included.

  According to the eighth aspect of the invention, during re-acceleration from the non-driven state of the one-way clutch, the turbine speed synchronized after the shift is determined to be the turbine speed used for calculating the target engine torque. In this way, when calculating the target engine torque, the synchronized turbine rotational speed after the shift is used, so that a transient delay of the target engine torque during the shift control can be avoided.

  According to a ninth aspect of the present invention, there is provided a driving force control apparatus that uses a torque converter characteristic from a turbine rotational speed and a target engine torque of a torque converter, in addition to the configuration of any one of the first to eighth aspects of the invention. Further comprising means for calculating. The control means includes means for controlling the engine based on the target engine speed in addition to the target engine torque.

  According to the ninth aspect of the invention, the target engine speed can also be calculated, and the engine can be controlled by obtaining the throttle opening and the ignition timing from the target engine torque and the target engine speed using the engine reverse characteristics. .

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

  With reference to FIG. 1, the whole block of the vehicle control system 1000 which concerns on this Embodiment is demonstrated. The braking system, steering system, suspension system, etc. are not shown.

  The vehicle control system 1000 includes an accelerator operation input detection unit 1100, a PDRM (Power Train Driver Model) 1200, a PTM (Power Train Manager) 1400, an engine control unit 1600, and a transmission (ECT (Electronically Controlled Automatic Transmission)) control unit. 1700.

  The accelerator operation input detection unit 1100 detects the opening degree of an accelerator pedal, which is the most common device in which a driver inputs a requested engine torque value. Here, the detected accelerator pedal opening (hereinafter, the accelerator opening may be described) is output to PDRM 1200.

  The PDRM 1200 includes a driver model 1210 and an arbitration unit 1220. Based on the accelerator opening detected by the accelerator operation input detection unit 1100, the reference throttle opening of the engine is calculated from a map or a function. This map or function is non-linear. Arbitration unit 1220 arbitrates between the requested throttle opening of the engine calculated by driving support unit 1300 such as cruise control and the reference throttle opening calculated by driver model 1210, for example. Note that the arbitrating unit 1220 is, for example, one of the requested throttle opening calculated by the driving support unit 1300 and the reference throttle opening calculated by the driver model 1210 based on the state of the vehicle at that time. Or a function that selects any larger opening, a function that selects any smaller opening, or the like.

  PTM 1400 includes an arbitration unit 1410, an engine torque request unit 1420, and an ECT gear stage determination unit 1430.

  Arbitration unit 1410 is, for example, the required throttle opening of the engine calculated in brake control / vehicle motion compensation unit 1500 such as VSC (Vehicle Stability Control) and VDIM (Vehicle Dynamics Integrated Management), and the required throttle calculated in PDRM 1200. Adjust the opening. Similarly to the arbitration unit 1220, the arbitration unit 1410 is calculated by the engine required throttle opening calculated by the brake control / vehicle motion compensation unit 1500 and the PDRM 1200 based on the state of the vehicle at that time, for example. It is realized by a function that gives priority to any one of the required throttle opening, a function that selects any larger opening, a function that selects any smaller opening, or the like. Based on the requested throttle opening adjusted by the arbitrating unit 1410, the engine torque requesting unit 1420 calculates the requested engine torque TEREQ and the requested engine speed NEREQ, and the gear stage determining unit 1430 determines the gear stage. Details of these will be described later.

  The engine control unit 1600 controls the engine based on the required engine torque TEREQ and the required engine speed NEREQ input from the PTM 1400. The shift control unit 1700 controls ECT based on the gear stage input from the PTM 1400. In the following description, the ECT is described as a stepped gear type automatic transmission, but the automatic transmission may be a CVT (Continuously Variable Transmission), in which case the gear stage has a gear ratio. It becomes. Further, any automatic transmission is provided with a torque converter. The torque converter has its input side (pump side) connected to the output shaft of the engine and its output side (turbine side) connected to the input shaft of the automatic transmission.

The control block of the PTM 1400 in FIG. 1 will be described with reference to FIG.
The arbitration unit 1410 in FIG. 1 is also described as the arbitration unit 1410 in FIG. Based on the torque request from the brake control / vehicle motion compensation unit 1500, the required throttle opening is calculated from the engine characteristics, and arbitration between the required throttle opening and the reference throttle opening calculated by the PDRM 1200 is performed as an arbitration. The unit 1410 executes.

  Based on the requested throttle opening adjusted by the arbitration unit 1410, the reference engine torque is calculated from the torque converter coupling diagram using the current turbine speed (current NT), or the synchronized turbine speed after the shift (synchronized) NT) is used to calculate the reference engine torque TE from the torque converter coupling diagram. In vehicle control system 1000 that is the driving force control apparatus according to the present embodiment, when calculating this reference engine torque TE, whether the current turbine speed NT is used or the synchronized turbine speed NT after the shift is used? The point is that is selected.

  Note that, based on the required throttle opening adjusted by the arbitrating unit 1410, the gear stage of the ECT is determined by the shift determining unit. This shift determination unit includes an AI (Artificial Intelligence) control function.

  As shown in FIG. 3, for example, the horizontal axis represents the turbine rotational speed NT (specifically, the turbine rotational speed NT is the output shaft rotational speed Nout × gear ratio of the automatic transmission). Is a map in which engine torque TT is used, and the throttle opening is a parameter. When the turbine speed NT and the throttle opening are determined, the turbine torque TT of the torque converter can be uniquely calculated. As shown in FIG. 3, the larger the throttle opening, the greater the turbine torque TT even at the same turbine speed NT. The turbine torque TT can be converted into the engine torque TE. Therefore, in FIG. 2, the reference engine torque TE is output from the torque converter coupling diagram.

  The torque converter coupling diagram shown in FIG. 3 is obtained by superimposing the torque converter characteristic diagram shown in FIG. 4 on the engine torque characteristic curve (the horizontal axis is the engine speed NE and the vertical axis is the engine torque TE). FIG. 4 shows the characteristic performance of a general torque converter, where t is the torque ratio, τ is the torque capacity, and η is the efficiency.

  The reference engine torque TE calculated from the torque converter connection diagram using either of the two turbine rotational speeds NT (current NT or synchronous NT) is adjusted with the engine torque request from the shift control unit 1700. Mediation by the department.

  The adjusted engine torque is output to the engine control unit 1600 as the requested engine torque TEREQ. Further, the adjusted engine torque is output to the engine control unit 1600 as the requested engine torque TEREQ. Further, the requested engine speed NEREQ is calculated from the torque converter characteristic diagram using the arbitrated engine torque and one of the two turbine speeds NT (current NT or synchronous NT).

  The engine control unit 1600 controls the engine by calculating the throttle opening and the ignition timing that realize the required engine torque TEREQ and the required engine speed NEREQ based on the engine reverse characteristics.

  With reference to FIG. 5, a control structure of a program executed in vehicle control system 1000 that is the control device according to the present embodiment will be described.

  In step (hereinafter, step is described as S) 100, vehicle control system 1000 detects an accelerator input signal. More specifically, the accelerator operation input detector 1100 detects the amount of operation of the accelerator pedal of the driver (accelerator pedal opening (accelerator opening)).

  At S110, vehicle control system 1000 calculates an expected G (acceleration) (expected driving force) of the vehicle. More specifically, for example, the predicted G (expected driving force) of the vehicle is calculated from the accelerator opening by the driver model 1210 of the PDRM 1200.

  In S120, vehicle control system 1000 calculates reference throttle opening degree TA (predicted throttle opening degree TA) from the predicted G (expected driving force) of the vehicle. More specifically, for example, the reference throttle opening degree TA is calculated from the expected G (expected driving force) of the vehicle by the driver model 1210 of the PDRM 1200.

  In S130, vehicle control system 1000 uses arbitration unit 1410 of PTM 1400 to arbitrate the requested throttle opening from brake control / vehicle motion compensation unit 1500 and reference throttle opening TA calculated in S120.

  In S140, vehicle control system 1000 executes calculation processing turbine speed NT selection processing (current NT or synchronous NT is selected) using PTM1400. Details of this process (subroutine) will be described later.

  In S150, vehicle control system 1000 uses PTM1400 to calculate turbine torque TT from calculation turbine speed NT and reference throttle opening TA using the torque converter coupling diagram shown in FIG. Convert to engine torque TE.

  In S160, vehicle control system 1000 uses the torque arbitration unit of PTM 1400 to arbitrate requested engine torque TE from transmission control unit 1700 and reference engine torque TE calculated in S150. At this time, for example, if the shift control is being performed, the request engine torque TE from the transmission control unit 1700 is preferentially processed.

  In S170, vehicle control system 1000 calculates requested engine torque TEREQ using the result of arbitration.

  In S180, vehicle control system 1000 calculates required engine speed NEREQ from calculation NT (current NT or synchronous NT) and reference engine torque TE using the torque converter characteristic diagram of FIG. .

  In S190, vehicle control system 1000 transmits requested engine torque TEREQ and requested engine speed NEREQ to engine control unit 1600.

With reference to FIG. 6, the details of the calculation NT selection process in S140 of FIG. 5 will be described.
In S300, vehicle control system 1000 determines whether or not shift control is being performed. This determination is made based on a signal from the shift control unit 1700. It is determined that the shift control is in progress from the output of the shift command to the completion of the shift. If it is determined that the shift control is being performed (YES in S300), the process proceeds to S310. If not (NO in S300), the process proceeds to S340.

  In S310, vehicle control system 1000 determines whether or not the shift is a downshift. This determination is also made based on a signal from the shift control unit 1700. If it is determined that the shift is a downshift (YES in S310), the process proceeds to S320. If not (NO in S310), the process proceeds to S330.

  In S320, vehicle control system 1000 determines whether or not the accelerator pedal has been gently depressed. If it is determined that the accelerator pedal is gently depressed (not a power-on downshift) (YES in S320), the process proceeds to S340. Otherwise (if power-on downshift) (NO in S320), the process proceeds to S350.

  In S330, vehicle control system 1000 determines whether the shift is an off-upshift shift or re-acceleration from a one-way clutch (OWC) non-drive state. An off-upshift shift is a shift that occurs when an upshift shift line is crossed while the accelerator pedal is not depressed. A one-way clutch (OWC) is a power transmission element in an automatic transmission, and is a mechanical element that transmits rotation only in one direction. When re-accelerated from the non-driving state, power is transmitted from the non-driving state to the driving state. If it is determined that the shift is either an off-up shift shift or re-acceleration from the one-way clutch (OWC) non-drive state (YES in S330), the process proceeds to S350. If not (NO in S330), the process proceeds to S340.

  In S340, vehicle control system 1000 substitutes current turbine speed NT for calculation turbine speed NT. In S350, vehicle control system 1000 substitutes synchronous turbine rotational speed NT (synchronous rotational speed after shifting) for calculation turbine rotational speed NT. After the processes of S340 and S350, the process proceeds to S150 of FIG.

  The operation of a vehicle equipped with a vehicle control system 1000 that is a control device according to the present embodiment based on the above-described structure and flowchart will be described.

  When the driver operates the accelerator pedal while driving the vehicle, the accelerator opening is detected (S100), the expected G (expected acceleration) is calculated (S110), and the reference throttle opening TA is calculated (S120). . Arbitration processing is executed with the reference throttle opening in the other system (S130), and the reference throttle opening is determined.

[When shift control is not in progress]
When the shift control is not being performed (NO in S300), the calculation turbine rotational speed NT for calculating the reference engine torque TE (calculated by converting the turbine torque TT in the torque converter coupling diagram of FIG. 3). The current turbine speed NT is substituted.

  Using the torque converter connection diagram shown in FIG. 3, the reference turbine torque TT is calculated from the calculation turbine speed NT and the reference throttle degree TA, and the reference engine torque TE is calculated by converting the reference turbine torque TT. Is done.

  The reference engine torque TE is adjusted (S160), and the adjusted engine torque TE is calculated as the required engine torque TEREQ (S170). Using the torque converter characteristic diagram shown in FIG. 4, the required engine speed NEREQ is calculated from the calculation turbine speed NT and the reference engine torque TE (S180).

  Requested engine torque TEREQ and requested engine speed NEREQ are transmitted to engine control unit 1600 to control the engine.

  When the speed change control is not being performed, a transient delay due to the speed change does not occur. Therefore, even if the current turbine speed NT is used as the calculation turbine speed NT, the response is not particularly deteriorated.

[When shifting control is being performed but neither off-upshifting nor reacceleration from non-OWC drive]
If shift control is in progress (YES in S300), but not downshift (NO in S310), neither off-upshifting nor re-acceleration after one-way clutch non-drive (NO in S330), reference engine torque The current turbine speed NT is substituted as the calculation turbine speed NT for calculating TE.

  Even during the shift control, if there is no off-up shift or re-acceleration after the one-way clutch is not driven, a transient delay is unlikely to occur, so the current turbine speed NT is used as the calculation turbine speed NT. However, the responsiveness is not particularly lowered.

[If downshift control is in progress but not power-on downshift]
If shift control is being performed (YES in S300), downshifting (YES in S310), and the accelerator pedal is being depressed gently (YES in S320), a power-on downshift is not performed. Therefore, the current turbine speed NT is substituted as the calculation turbine speed NT for calculating the reference engine torque TE.

  Even during downshift control, if there is no power-on downshift, a transient delay is unlikely to occur, so even if the current turbine speed NT is used as the calculation turbine speed NT, the responsiveness is particularly lowered. There is nothing to do.

[In case of power-on downshift, off-upshift, re-acceleration from non-OWC drive]
If shift control is being performed (YES in S300), downshifting (YES in S310), and the accelerator pedal is not being depressed gently (NO in S320), a power-on downshift is performed. Thus, the synchronized turbine rotational speed NT is substituted for the rotational speed after shifting as the operational turbine rotational speed NT for calculating the reference engine torque TE.

  If shift control is being performed (YES in S300) and not a downshift (NO in S310), but off-shift or re-acceleration after one-way clutch non-drive (YES in S330), reference engine torque The synchronized turbine rotational speed NT is substituted for the rotational speed after shifting as the operational turbine rotational speed NT for calculating TE.

  Such a shift or a time delay is required to change the one-way clutch from the non-driven state to the driven state, and a transient delay occurs. For this reason, the driving force after the shift is requested by prefetching the transient delay. For this purpose, the synchronized turbine rotation speed NT after the shift is used as the calculation turbine rotation speed NT for calculating the reference engine torque TE. In particular, since the change speed of the turbine speed is slower than the change speed of the engine speed, the reference engine torque is determined by using the current turbine speed NT in such a speed change or when the one-way clutch is re-accelerated from the non-driven state. If TE is calculated, the response delay becomes large. However, since the required engine torque TE is calculated by prefetching the change in the turbine rotational speed by using the synchronous turbine rotational speed, a response delay hardly occurs. As a result, the response delay can be compensated for, so that the feeling of acceleration delay and the lack of acceleration can be eliminated.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

1 is an overall block diagram of a vehicle control system according to an embodiment. FIG. 2 is a control block diagram of the power train manager of FIG. 1. It is a coupling diagram of a torque converter. It is a characteristic diagram of a torque converter. It is a flowchart which shows the control structure of the program performed with the vehicle control system which concerns on this Embodiment. It is a flowchart which shows the control structure of the subroutine program of S140 of FIG.

Explanation of symbols

  1000 vehicle control system, 1100 accelerator operation detection unit, 1200 PDRM, 1210 driver model, 1220 arbitration unit, 1300 driving support unit, 1400 PTM, 1410 arbitration unit, 1420 engine torque request unit, 1430 gear stage determination unit, 1500 brake control / Vehicle motion compensation unit, 1600 engine control unit, 1700 shift control unit.

Claims (9)

A driving force control device for a vehicle equipped with a power train comprising an engine and a transmission connected to the engine via a torque converter,
Target torque setting means for setting a target engine torque of the engine;
Control means for controlling the engine based on the target engine torque output from the target torque setting means,
The target torque setting means includes a means for setting the target engine torque based on a throttle opening of the engine and a turbine speed of a torque converter.   The target torque setting means takes into account the performance of the engine and the characteristics of the torque converter, and uses the target engine torque based on information defining the relationship between the turbine speed and the turbine torque using the throttle opening as a parameter. The vehicle driving force control device according to claim 1, comprising means for calculating   The target torque setting means takes into account the engine performance and the characteristics of the torque converter, and uses the target engine torque based on a map that defines the relationship between the turbine speed and the turbine torque using the throttle opening as a parameter. The vehicle driving force control apparatus according to claim 1, comprising means for calculating The driving force control device includes:
Means for detecting a shift state of the transmission;
Means for detecting the driver's accelerator operating state,
The target torque setting means determines a turbine rotational speed used for calculating the target engine torque based on the shift state and the accelerator operation state, and is calculated using the determined turbine rotational speed. The vehicle driving force control device according to claim 2, further comprising means for calculating the target engine torque using turbine torque.   The target torque setting means is means for calculating the target engine torque using the turbine torque calculated using the synchronous turbine speed after the shift when the shift state is a power-on downshift shift. The vehicle driving force control device according to claim 4, comprising:   The target torque setting means is means for calculating the target engine torque using the turbine torque calculated using the synchronous turbine speed after the shift when the shift state is an off-upshift shift. The vehicle driving force control apparatus according to claim 4, further comprising: The driving force control device includes:
Means for detecting the state of the one-way clutch of the transmission;
Means for detecting the driver's accelerator operating state,
The target torque setting means determines a turbine speed used to calculate the target engine torque based on the state of the one-way clutch and the accelerator operation state, and calculates using the determined turbine speed. The vehicle driving force control apparatus according to claim 2, further comprising means for calculating the target engine torque using the turbine torque that has been generated.   The target torque setting means calculates the target engine torque using the turbine torque calculated using the synchronized turbine rotational speed after the shift when the one-way clutch is being reaccelerated from the non-driven state. The vehicle driving force control apparatus according to claim 7, comprising means for The driving force control apparatus further includes means for calculating a target engine speed from a turbine speed of the torque converter and a target engine torque using a torque converter characteristic,
The vehicle driving force control device according to claim 1, wherein the control means includes means for controlling the engine based on the target engine speed in addition to the target engine torque.

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