JP2011207240A - Vehicle control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle control system allowing improvement of mileage.SOLUTION: The vehicle control system includes an engine, and an automatic transmission transmitting power outputted by the engine to drive wheels of a vehicle. In the vehicle control system, a target torque of the engine and a target gear shift ratio of the automatic transmission are determined based on a predetermined prescribed operation line indicating the relation between an engine speed and output torque of the engine, and a target value related to acceleration of the vehicle (54); a delay compensation is applied to at least one of a torque instruction that is an instruction to make the engine achieve the target torque and a gear shift instruction that is an instruction to make the automatic transmission achieve the target gear shift ratio, and output can be performed (54-56-58A, 54-57-58B). The delay compensation suppresses that an operation point comes apart from the prescribed operation line more as compared to when the delay compensation is not applied, in a process wherein the operation point indicating the output torque and the engine speed changes to a target operation point corresponding to the target torque and the target gear shift ratio.

Description

  The present invention relates to a vehicle control system.

  2. Description of the Related Art Conventionally, in a vehicle equipped with an engine and an automatic transmission, there is known a technique for determining an engine operating state and a target value for a gear ratio of the automatic transmission, and controlling the engine and the automatic transmission based on the target values. ing.

  For example, in Patent Document 1, a control target value is temporarily generated based on a request of a driver or an automatic driving device, and based on the control target value, the same physical quantity dimension as that of the control target value and values mutually. Two control target values with different values are generated in the middle, and based on the control target values generated in the middle, the physical quantity dimension or type of control target (target engine torque) suitable for the control of each of the drive source and the transmission , A target gear stage) is finally generated, and a technology of a vehicle integrated control device that controls a drive source and a transmission toward each finally generated control target is disclosed.

JP 2006-281925 A

  Here, in a vehicle in which a target torque for the engine and a target speed ratio for the automatic transmission are determined based on a predetermined engine operating line (predetermined operating line), the engine responsiveness and the automatic transmission responsiveness If they are different, fuel consumption may be reduced. For example, in the process in which the engine operating point changes to the target operating point, the operating point becomes an operating point away from a predetermined operating line due to the difference between the response of the engine and the response of the automatic transmission. May decrease.

  An object of the present invention is to provide a vehicle control system capable of improving fuel consumption in a vehicle in which an engine and an automatic transmission are controlled based on a target torque and a target gear ratio.

  A vehicle control system according to the present invention includes an engine and an automatic transmission that transmits power output from the engine to drive wheels of the vehicle, and is a predetermined value indicating a relationship between the output torque of the engine and the rotational speed. A torque command which is a command for determining a target torque of the engine and a target gear ratio of the automatic transmission based on an operation line and a target value related to the acceleration of the vehicle and causing the engine to realize the target torque; or It is possible to perform delay compensation on at least one of a shift command that is a command for realizing the target gear ratio in the automatic transmission, and the delay compensation indicates the output torque and the rotation speed. In the process in which the operating point changes to the target operating point corresponding to the target torque and the target gear ratio, the delay compensation is not performed. , Characterized in that the operating point is to prevent the leaves from the predetermined operation line.

  In the vehicle control system, it is preferable that the predetermined operation line indicates a relationship between the output torque at which the engine can be operated with optimum fuel consumption and the rotation speed.

  In the vehicle control system, the delay compensation is preferably performed based on at least one of a response delay of the engine to the torque command and a response delay of the automatic transmission to the shift command.

  In the vehicle control system, it is preferable that the delay compensation is performed so that the operating point becomes an operating point on the predetermined operating line in the process of changing to the target operating point.

  In the vehicle control system, a target value related to the acceleration is determined based on an operation amount of an operation member operated by a driver, and a magnitude of the target value related to the acceleration or a change speed of the target value related to the acceleration. It is preferable to determine whether or not to perform the delay compensation based on at least one of the sizes of.

  A vehicle control system according to the present invention determines a target torque of an engine and a target gear ratio of an automatic transmission based on a predetermined operation line determined in advance and a target value related to acceleration of the vehicle, and sets the target torque to the engine. Delay compensation can be applied to at least one of a torque command, which is a command to be realized, or a shift command, which is a command to realize a target gear ratio in the automatic transmission, and the output can be output. The delay compensation suppresses the operating point from moving away from the predetermined operating line in the process in which the operating point changes to the target operating point corresponding to the target torque and the target gear ratio, compared to the case where no delay compensation is performed. . Therefore, according to the vehicle control system of the present invention, there is an effect that fuel efficiency can be improved.

Drawing 1 is a figure showing the important section of the vehicle control system concerning an embodiment. FIG. 2 is a schematic configuration diagram illustrating the vehicle according to the embodiment. FIG. 3 is a diagram for explaining a method of determining a target value.

  Hereinafter, an embodiment of a vehicle control system according to the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited by this embodiment. In addition, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art or those that are substantially the same.

(First embodiment)
The first embodiment will be described with reference to FIGS. 1 to 3. The present embodiment relates to a vehicle control system. FIG. 1 is a diagram illustrating a main part of a vehicle control system according to an embodiment of the present invention, and FIG. 2 is a schematic configuration diagram illustrating a vehicle according to the embodiment.

  The vehicle control system 1-1 of the present embodiment controls the engine torque and the transmission gear ratio so that the engine is always operated on the fuel efficiency optimum line, thereby improving fuel efficiency. Taking into account engine responsiveness and transmission responsiveness, dynamic fuel consumption can be compensated by delaying or compensating for commands to the engine and transmission gear ratio so that the engine operates dynamically on the fuel efficiency optimum line. Can be improved.

  More specifically, the vehicle control system 1-1 determines the engine torque and the automatic transmission gear ratio (speed stage) so as to minimize the fuel consumption based on the fuel consumption rate information of the engine. In the transmission control device, a request is made to the engine and the transmission through response compensation means (responsiveness compensator) that compensates each response for the determined target engine torque and target speed ratio. Each response compensation means is set so that the response time from the target engine torque to the actual engine torque is the same as the response time from the target gear ratio to the actual gear ratio. As a result, engine operation can be dynamically performed on the fuel efficiency optimum line, and deterioration of fuel efficiency is suppressed even when the required travel power changes frequently.

  Further, the response compensation means is set only for a scene where the driver does not intentionally accelerate / decelerate. Therefore, in the vehicle control system 1-1 of the present embodiment, acceleration / deceleration responsiveness is emphasized in a scene where a quick response from the accelerator to the vehicle G is required, and if not, the actual fuel consumption is emphasized engine torque and speed ratio control. It is possible to improve both the fuel efficiency and the actual fuel consumption.

  FIG. 2 is a schematic configuration diagram of a vehicle to which the vehicle control system according to the present embodiment is applied. In FIG. 2, the code | symbol 1 shows a vehicle. The power train of the vehicle 1 includes an engine 10, a torque converter 20, and a continuously variable transmission 30. A continuously variable transmission (CVT) 30 as an automatic transmission is connected to the engine 10 as an internal combustion engine via a torque converter 20. The engine output torque (driving force) of the engine 10 is input to the continuously variable transmission 30 via the torque converter 20 and transmitted to the drive wheels 90 via the differential gear 18 and the drive shaft 19. That is, the continuously variable transmission 30 is an automatic transmission that transmits the power output from the engine 10 to the drive wheels 90 of the vehicle 1.

  The continuously variable transmission 30 is a well-known belt-type continuously variable transmission, and is provided on the engine side. The primary pulley 31 connected to the output shaft 70 of the torque converter 20 and the output shaft 80 connected to the differential gear 18. The secondary pulley 32 is connected to the belt 33 and the belt 33 is stretched between them. The hydraulic control device 40 changes the gear ratio of the continuously variable transmission 30 in accordance with a gear ratio change command input from the ECU 50. The hydraulic control device 40 supplies a predetermined line pressure to the primary pulley side actuator and the secondary pulley side actuator, and adjusts the operating oil pressure (primary oil pressure) of the primary pulley side actuator and the operating oil pressure of the secondary pulley side actuator. . The hydraulic control device 40 can change the pulley ratio and change the gear ratio steplessly by adjusting the hydraulic pressure of the primary pulley side actuator and the hydraulic pressure of the secondary pulley side actuator.

  The continuously variable transmission 30 includes a primary pulley rotation sensor 34 that detects the rotation speed (primary rotation speed) of the primary pulley 31 and a secondary pulley rotation sensor 35 that detects the rotation speed (secondary rotation speed) of the secondary pulley 32. And the detected primary rotational speed and secondary rotational speed are output to the ECU 50.

  The torque converter 20 connects the continuously variable transmission 30 and the engine 10. The torque converter 20 has a known lock-up mechanism, and is a torque converter with a lock-up clutch that is a power interrupting means that can be coupled and released. The lockup clutch performs mechanical coupling (lockup state) or release (converter state) between the engine 10 and the continuously variable transmission 30. The input shaft 60 of the torque converter 20 is provided with a rotational speed sensor 21 that detects the rotational speed of the input shaft 60. The input shaft rotational speed detected by the rotational speed sensor 21 is output to the ECU 50.

  The vehicle 1 is provided with an ECU (electronic control unit) 50 that controls the engine 10, the continuously variable transmission 30, and the like. The ECU 50 includes the engine 10, the torque converter 20, and the continuously variable transmission 30 (hydraulic control device). 40) Comprehensive control is performed. The ECU 50 includes an input / output device, a storage device (ROM, RAM, etc.) that stores a control map and a control program, an arithmetic device, an A / D converter, a D / A converter, a communication driver circuit, and the like. . The vehicle control system of this embodiment includes an engine 10, a continuously variable transmission 30, and an ECU 50.

  Further, the vehicle is provided with an accelerator position sensor 11 that detects the amount of operation of the accelerator pedal (accelerator opening), and the detected accelerator opening is output to the ECU 50. An electronic throttle valve 13 is provided in the intake pipe 12 of the engine 10, and the electronic throttle valve 13 can be opened and closed by a throttle actuator 14. The ECU 50 drives the electronic throttle valve 13 by the throttle actuator 14 and can control the throttle opening to an arbitrary opening regardless of the accelerator opening. A throttle position sensor 15 for detecting the fully closed state of the electronic throttle valve 13 and the throttle opening is provided, and the detected throttle opening is output to the ECU 50. Reference numeral 23 denotes an exhaust pipe of the engine 10.

  The engine 10 is provided with an engine speed sensor 17 that detects an engine speed (engine speed), and the detected engine speed is output to the ECU 50. Further, the vehicle is provided with a vehicle speed sensor 41 for detecting the traveling speed of the vehicle and a shift position sensor 42 for detecting the position of the shift lever operated by the driver, and the detected vehicle speed and shift are detected. The position is output to the ECU 50.

  The ECU 50 determines the fuel injection amount, the injection timing, the ignition timing, and the like based on the operating state of the engine 10 such as the engine speed, the intake air amount, and the throttle opening, and controls the injector, the ignition plug, and the like. Further, the ECU 50 has a shift map, determines the gear ratio of the continuously variable transmission 30 based on the throttle opening, the vehicle speed, and the like, and the hydraulic control device 40 so as to establish the determined gear ratio. To control.

  The ECU 50 determines the target driving force based on the driver's request based on the accelerator opening as the input value and the vehicle speed (corresponding to the output rotational speed of the continuously variable transmission 30), as will be described below. Based on the determined target driving force, so-called driving force demand control is performed in which the output torque of the engine 10 is controlled. Further, the ECU 50 takes into account the responsiveness of the engine 10 and the responsiveness of the continuously variable transmission 30, or delays the command to the engine and the continuously variable transmission 30 so that the engine dynamically operates on the fuel efficiency optimum line. Has a function to compensate for lead.

  FIG. 1 is a diagram showing details of the ECU 50. The ECU 50 includes a target acceleration calculation unit 51, a target driving force calculation unit 52, a running resistance calculation unit 53, a target value calculation unit 54, a running state determination unit 55, a CVT shift response compensator 56, an engine torque response compensator 57, It has switch part 58 (58A, 58B).

  The target acceleration calculation unit 51 calculates a target acceleration. The vehicle speed detected by the vehicle speed sensor 41 and the accelerator opening detected by the accelerator position sensor 11 are respectively sent to the target acceleration calculation unit 51. The target acceleration calculation unit 51 calculates the target acceleration based on the acquired current vehicle speed and accelerator opening. The ECU 50 stores in advance a map (target acceleration map) indicating a correspondence relationship between the vehicle speed, the accelerator opening, and the target acceleration, and the target acceleration calculation unit 51 refers to the target acceleration map to calculate the target acceleration. decide. That is, the target acceleration calculation unit 51 determines a target value (target acceleration) related to acceleration based on an operation amount (accelerator opening) of an operation member (accelerator pedal or the like) operated by the driver. The determined target acceleration is sent to the target driving force calculation unit 52.

  The target driving force calculation unit 52 calculates a target driving force corresponding to the target acceleration based on the target acceleration sent from the target acceleration calculation unit 51. For example, the target driving force calculation unit 52 determines the target driving force based on the acquired target acceleration and the mass of the vehicle 1.

  The running resistance calculation unit 53 calculates the running resistance of the vehicle 1. For example, the running resistance calculation unit 53 calculates the driving force for each resistance of air resistance, rolling resistance, and gradient resistance. The running resistance calculation unit 53 calculates the running resistance based on, for example, the vehicle speed, the road surface friction coefficient, the running road gradient, and the like. The running resistance calculation unit 53 determines a value obtained by converting the calculated running resistance into a driving force acting on the vehicle 1 as a driving force for the running resistance.

  The target value calculation unit 54 calculates a control target for the engine 10 and a control target for the continuously variable transmission 30. Specifically, the target value calculation unit 54 calculates a target engine speed that is a target value of the engine speed and a target engine torque that is a target value of the engine output torque. A target power is input to the target value calculation unit 54. The target power is determined based on the target driving force determined by the target driving force calculation unit 52, the driving force corresponding to the traveling resistance determined by the traveling resistance calculation unit 53, and the vehicle speed detected by the vehicle speed sensor 41. Is. The target power is calculated, for example, as the product of the required driving force and the vehicle speed determined from the target driving force and the driving force corresponding to the running resistance.

  The target value calculation unit 54 determines the target value based on the acquired target power as described below with reference to FIG. FIG. 3 is a diagram for explaining a method of determining a target value.

  In FIG. 3, the horizontal axis indicates the engine speed, and the vertical axis indicates the engine output torque. Reference numeral 101 denotes an equal power line. The equal power line 101 is a line that connects operating points of the engine 10 (combination of engine speed and engine output torque) at which the output (power) of the engine 10 is equal. Reference numeral 102 denotes a predetermined fuel efficiency optimum line. The fuel efficiency optimal line 102 is a predetermined predetermined operation line indicating the relationship between the output torque of the engine 10 and the engine speed. If the operating line of the engine 10 is an operating point on the fuel efficiency optimal line 102, the engine 10 can be operated with good fuel efficiency. If the operating point is away from the fuel optimal line 102, the fuel efficiency decreases. The fuel efficiency optimal line 102 of the present embodiment is a line that connects operating points at which the engine 10 can be operated with the best fuel efficiency when the engine 10 outputs equal power. That is, the fuel efficiency optimum line 102 shows the relationship between the output torque of the engine 10 that can drive the engine 10 with the optimum fuel efficiency and the engine speed.

  When the power to be output by the engine 10 is determined, the best fuel consumption can be obtained by operating the engine 10 at the operating point X of the intersection of the equal power line 101 and the fuel efficiency optimum line 102 corresponding to the target power. Thus, the engine 10 can be operated to achieve the target power. Reference numerals Ne1 and Te1 respectively indicate a target engine speed and a target engine torque corresponding to the operating point (target operating point) X of the intersection of the equal power line 101 and the fuel efficiency optimal line 102.

  The fuel efficiency optimal line 102 may be a band having a width, and there may be a plurality of fuel efficiency optimal lines selected according to the external environment or the like.

  The ECU 50 stores in advance, for example, a map of a correspondence relationship between the power output from the engine 10 and the operating point of the engine 10 that can output the power with optimum fuel consumption. The target value calculation unit 54 refers to the map and determines the target engine speed Ne1 and the target engine torque Te1 based on the target power. Here, the target power is determined from the target acceleration that is a target value related to the acceleration of the vehicle 1, and the required speed ratio that is the target speed ratio of the continuously variable transmission 30 is determined from the target engine speed Ne1. . That is, the ECU 50 determines the target torque of the engine 10 and the target speed ratio of the continuously variable transmission 30 based on the target value related to the acceleration of the vehicle 1 and the fuel efficiency optimum line.

Here, when the shift control of the continuously variable transmission 30 based on the target engine speed Ne1 and the torque control of the engine 10 based on the target engine torque Te1, actual fuel consumption in the following situations is greatly deteriorated. There are things to do.
(1) JC08 mode and other driving patterns with slow acceleration / deceleration (2) Driving on roads with ups and downs (gradient) (3) Follow-up driving (4) Driving with poor drivers (5) Power weight ratio Driving in a small powerless car

  This is because when the required driving force (power) changes, the engine operation at the operating point on the fuel efficiency optimum line is caused by the difference in the response of the engine 10 and the response of the T / M (the continuously variable transmission 30). This is because it can hardly be done. As the driver is not good at driving, the power weight ratio is smaller, and the road has a greater change in slope, the required power changes more frequently, so the actual fuel consumption tends to deteriorate.

  The vehicle control system 1-1 of the present embodiment is delayed by a CVT shift response compensator 56 and an engine torque response compensator 57, which will be described below, respectively, with a shift command for the continuously variable transmission 30 and a torque command for the engine 10. Compensation can be applied. The CVT shift response compensator 56 can output the target engine speed Ne1 with at least delay compensation. By performing delay compensation on the target engine speed Ne1, delay compensation is applied to a shift command that is a command for causing the continuously variable transmission 30 to realize the target gear ratio, and the resultant is output. The engine torque response compensator 57 can output the target engine torque Te1 with at least delay compensation. By applying delay compensation to the target engine torque Te1, delay compensation is applied to the torque command, which is a command for causing the engine 10 to realize the target torque, and output. By performing such delay compensation, a dynamic reduction in fuel consumption due to the difference between the response of the engine 10 and the response of the continuously variable transmission 30 is suppressed.

The CVT shift response compensator 56 compensates for a delay or a lead in response to a command to the continuously variable transmission 30 for a target gear ratio based on the target engine speed Ne1 determined by the target value calculator 54. The CVT shift response compensator 56 includes a delay compensator 56A and a lead compensator 56B. The delay compensator 56A and the lead compensator 56B are connected in series. The delay compensator 56A compensates for the delay of the engine response. The engine response delay, which is the response delay of the engine 10 with respect to the torque command, is due to the engine response time constant T _eng and the engine response _dead time T _{d_eng} . The response _dead time T _{d_eng} is a _dead time from when a torque command for changing the output torque of the engine 10 is output until the actual engine output torque starts to change. The response time constant T _eng is a required time from when the engine output torque starts to change until reaching a predetermined engine output torque between the engine output torque at the start of the change and the target engine torque.

The transfer function C _CVT (s) of the CVT shift response compensator 56 can be expressed, for example, by the following [Equation 1]. Note that s is a Laplace operator, and T1 and T2 are time constants of the lead compensator 56B.

In [Formula 1] above, the parentheses on the right side are the transfer function of the delay compensator 56A, and the fractional part including T1 and T2 is the transfer function of the advance compensator 56B. The delay compensator 56A can produce a delay with respect to the input signal in accordance with the engine response _dead time T _{d_eng} and output it as the required engine speed for the continuously variable transmission 30. For example, the response dead time _{T D_eng} the engine 10 is greater than the response dead time _{T D_cvt} of the continuously variable transmission 30, lag compensator 56A may be set to delay the required engine rotational speed. Further, the delay compensator 56A can output the change rate of the requested engine speed as a small value with respect to the change rate of the input signal in accordance with the response time constant T _eng of the engine 10. For example, when the response time constant T _eng of the engine 10 is larger than the response time constant T _CVT of the continuously variable transmission 30 (the time required for changing the engine output torque is longer than the time required for changing the gear ratio). The delay compensator 56A may reduce the change speed of the required engine speed with respect to the input signal.

Note that the response _dead time T _{d_eng} and the response time constant T _eng of the engine 10 change depending on the operating state such as the engine speed. The ECU 50 stores in advance, for example, a map of a correspondence relationship between the operating state of the engine 10, the response _dead time T _{d_eng} of the engine 10 and the response time constant T _eng, and the operating state. Further, the response _dead time T _{d_cvt} and the response time constant T _CVT of the continuously variable transmission 30 change depending on the operation state such as the gear ratio before the shift. The ECU 50 stores in advance a correspondence relationship between the operating state of the continuously variable transmission 30 and the response _dead time T _{d_cvt} of the continuously variable transmission 30 and the response time constant T _CVT as, for example, a map. The CVT shift response compensator 56 and the engine torque response compensator 57 can perform delay compensation with each response dead time and response time constant determined by these maps.

  The advance compensator 56B is a compensator that adjusts the responsiveness of the overall control combining the shift control and the torque control. For example, in the advance compensator 56B, if T1> T2, the phase advance element can be used, and the response from the accelerator operation to the realization of the target power can be improved. Further, in the lead compensator 56B, if T1 <T2, it can be a phase delay element. The time constants T1 and T2 are determined in advance based on the responsiveness of the engine 10 and the responsiveness of the continuously variable transmission 30 from the viewpoint of improving fuel efficiency and drivability such as control responsiveness.

The CVT shift response compensator 56 performs delay compensation and lead compensation by the transfer function C _CVT (s) on the input target engine speed Ne1, and outputs the result as the required engine speed. The requested engine speed is output via the switch unit 58A. The ECU 50 determines the required speed ratio of the continuously variable transmission 30 based on the required engine speed. The required speed ratio is determined based on the rotational speed of the input shaft (output shaft 70 of the torque converter 20) of the continuously variable transmission 30 corresponding to the required engine speed and the current rotational speed of the output shaft 80. The ECU 50 outputs a hydraulic control command (shift command) to the hydraulic control device 40 so as to realize the determined required gear ratio. The hydraulic control device 40 adjusts the hydraulic pressure of the primary pulley side actuator and the hydraulic pressure of the secondary pulley side actuator to realize the required gear ratio.

The engine torque response compensator 57 performs a delay or advance compensation on the command to the engine 10 of the target engine torque Te1 determined by the target value calculation unit 54. The engine torque response compensator 57 includes a delay compensator 57A and a lead compensator 57B. The delay compensator 57A and the lead compensator 57B are connected in series. The delay compensator 57A performs delay compensation for the CVT response delay. The CVT response delay, which is the response delay of the continuously variable transmission 30 with respect to the shift command, is due to the response time constant T _CVT of the continuously variable transmission 30 and the response _dead time T _{d_cvt} of the continuously variable transmission 30. The CVT response delay indicates a response delay of the hydraulic control device 40 and the continuously variable transmission 30 when a shift command is output to the continuously variable transmission 30 (hydraulic control device 40). The response _dead time T _{d_cvt} is a _dead time from when the gear shift command is issued until the gear ratio of the continuously variable transmission 30 starts to change. The response time constant T _CVT is a time required from when the gear ratio starts to change until the gear ratio changes to a predetermined gear ratio between the gear ratio before the gear shift and the target gear ratio. The target speed ratio is a speed ratio of the continuously variable transmission 30 corresponding to the target engine speed Ne1.

The transfer function C _ENG (s) of the engine torque response compensator 57 can be, for example, as shown in the following [Equation 2].

In [Formula 2], the parentheses on the right side are the transfer function of the delay compensator 57A, and the fractional part including T1 and T2 is the transfer function of the advance compensator 57B. The delay compensator 57 _{</ b> A} can generate a delay with respect to the input signal according to the response _dead time T _{d_cvt} of the continuously variable transmission 30 and output it as a required engine torque for the engine 10. For example, the response dead time _{T D_cvt} of the continuously variable transmission 30 is greater than the response dead time _{T D_eng} the engine 10, a delay compensator 57A may be set to delay the required engine torque. Also, lag compensator 57A may, depending on the response time constant T _CVT of the continuously variable transmission 30, and outputs a change rate of the required engine torque as small as against the rate of change of the input signal. For example, when the response time constant T _CVT of the continuously variable transmission 30 is larger than the response time constant T _eng of the engine 10, the delay compensator 57A reduces the change speed of the required engine torque with respect to the input signal. May be.

  The advance compensator 57B is a compensator that adjusts the responsiveness of the overall control combining the shift control and the torque control, like the advance compensator 56B. In this embodiment, the advance compensator 56B of the CVT shift response compensator 56 and the advance compensator 57B of the engine torque response compensator 57 have the same characteristics.

The engine torque response compensator 57 performs delay compensation and lead compensation by the transfer function C _ENG (s) on the inputted target engine torque Te1, and outputs the result as requested engine torque. The ECU 50 controls the engine 10 based on the required engine torque output from the engine torque response compensator 57 via the switch unit 58B. The ECU 50 outputs a command (torque command) relating to the throttle opening, fuel injection amount, injection timing, ignition timing, etc. of the electronic throttle valve 13 so that the actual engine output torque is the required engine torque.

As described above, the shift command of the continuously variable transmission 30 is delayed or advanced compensated based on the response of the engine 10, and the delay or advance compensation of the torque command of the engine 10 is compensated based on the response of the continuously variable transmission 30. As a result, the occurrence of a shift between the timing at which the required engine torque is realized in the engine 10 and the timing at which the required speed ratio is realized in the continuously variable transmission 30 is suppressed. The delay compensation based on the engine response _dead time T _{d_eng} and the continuously variable transmission response time T _{d_cvt} is applied, so that the engine output torque Te changes in advance or the engine speed Ne changes in advance. Thus, the operating point of the engine 10 is prevented from being an operating point away from the fuel efficiency optimum line. Further, also by a delay compensation based on the response time constant T _CVT when the response of the engine constant T _eng and a continuously variable transmission is applied, it is suppressed to be operating point the operating point away from the optimum fuel economy line . That is, the delay compensation performed by the vehicle control system 1-1 suppresses the operation point from moving away from the fuel efficiency optimal line in the process of changing the operating point to the target operating point X, compared to the case where the delay compensation is not performed. Is.

  Further, the delay compensation by the vehicle control system 1-1 is performed, so that the operating point of the engine 10 draws a linear locus toward the target operating point X indicating the target engine speed Ne1 and the target engine torque Te1. . Therefore, the operating point can be shifted along the optimal fuel efficiency line from the current operating point on the optimal fuel efficiency line to a new target operating point on the optimal fuel efficiency line. That is, the vehicle control system 1-1 performs delay compensation so that the operating point becomes an operating point on the fuel efficiency optimum line in the process of changing the operating point to the target operating point X.

  Thus, according to the vehicle control device 1-1 of the present embodiment, the operating point of the engine 10 is suppressed from being an operating point that deviates from the fuel efficiency optimal line, and fuel efficiency can be improved. In the process where the target power changes and the operating point changes, the engine 10 can always be operated at the operating point on the fuel efficiency optimal line, and the dynamic fuel efficiency can be improved.

  In the present embodiment, delay compensation is performed only for scenes where the driver is not intentionally accelerating or decelerating. The traveling state determination unit 55 determines whether the current traveling state is a traveling state of steady traveling, slow acceleration traveling, or slow deceleration traveling, or a traveling state different from any of these traveling states. . That is, the traveling state determination unit 55 determines whether or not the driver intentionally performs an acceleration operation or a deceleration operation. The traveling state determination unit 55 makes this determination based on the target driving force determined by the target driving force calculation unit 52, for example. Here, the target driving force is a target value related to the acceleration of the vehicle 1 that is determined based on the operation amount (accelerator opening) of the operation member (in this case, the accelerator pedal) operated by the driver.

  The running state determination unit 55 is at least one of a case where the target driving force for acceleration is smaller than a predetermined value, or a case where the magnitude of the change speed of the target driving force is equal to or less than a predetermined speed. In one case, it can be determined that the current running state is any one of steady running, slow acceleration running, and slow deceleration running.

  When the current running state is one of steady running, slow acceleration running, and slow deceleration running, the running state determination unit 55 determines that the target engine speed Ne1 and the target engine torque Te1 are compensated for CVT shift responsiveness, respectively. The switch unit 58A and the switch unit 58B are switched so as to be output via the controller 56 and the engine torque response compensator 57.

  The switch unit 58A includes a state in which the target engine speed Ne1 output from the target value calculation unit 54 is output via the CVT shift response compensator 56 and a shift command is issued, and the target engine speed Ne1 is CVT shift response. The state is switched to a state in which a shift command is issued without being transmitted through the performance compensator 56. When the target engine speed Ne1 is output as it is without being passed through the CVT shift response compensator 56 (bypassed), the shift command to the continuously variable transmission 30 is not subjected to delay compensation (and advance compensation), A shift command is output so as to realize the required gear ratio based on the target engine speed Ne1.

  The switch unit 58B includes a state where the target engine torque Te1 output from the target value calculation unit 54 is output via the engine torque response compensator 57 and a torque command is issued, and the target engine torque Te1 is compensated for engine torque response. Switching between the state in which the torque command is issued without being routed through the device 57 is performed. When the target engine torque Te1 is output without being passed through the engine torque response compensator 57 (bypassed), the target engine torque Te1 is not compensated for delay (and lead compensation) in the torque command for the engine 10. A torque command is output so as to realize

  When the traveling state determination unit 55 determines that the current traveling state is not any of the steady state, slow acceleration travel, and slow deceleration travel, the CVT shift response compensator 56 and the engine torque response compensator 57 are provided. Are switched between the switch part 58A and the switch part 58B. As a result, the shift command and the torque command are output without delay compensation applied to any of the target engine speed Ne1 and the target engine torque Te1. That is, the vehicle control system 1-1 determines whether to perform delay compensation based on at least one of the magnitude of the target value related to acceleration and the magnitude of the change speed of the target value related to acceleration. The target value related to acceleration when delay compensation is performed is smaller than the target value related to acceleration when delay compensation is not performed. Further, the magnitude of the change rate of the target value related to the acceleration when the delay compensation is performed is smaller than the magnitude of the change speed of the target value related to the acceleration when the delay compensation is not performed.

  In this way, when the target value related to acceleration is large or the change speed of the target value related to acceleration is large, in other words, in a scene where a quick response from the accelerator operation to the vehicle acceleration is required, responsiveness without delay compensation is performed. The vehicle control with an emphasis on is executed. Therefore, according to the vehicle control system 1-1 of the present embodiment, it is possible to achieve both improvement in fuel efficiency and improvement in drivability.

  In the present embodiment, the case where the automatic transmission mounted on the vehicle 1 is the continuously variable transmission 30 has been described. However, the present invention is not limited to this, for example, a stepped transmission as an automatic transmission, The vehicle control system of this embodiment may be applied to a vehicle on which a known automatic transmission is mounted.

  In the present embodiment, the case where the target acceleration is determined based on the accelerator opening and the vehicle speed has been described, but the present invention is not limited to this. For example, even when the target acceleration is determined (or corrected) on the vehicle side such as following driving, fuel efficiency can be improved by vehicle control by the vehicle control system 1-1 of the present embodiment.

(First Modification of Embodiment)
In the above embodiment, the delay compensation is performed based on both the response dead time and the response time constant. However, the present invention is not limited to this. For example, delay compensation based on only one of the response dead time or the response time constant may be performed. Further, delay compensation may be performed based on a parameter indicating responsiveness other than the response dead time and the response time constant.

(Second Modification of Embodiment)
In the above embodiment, delay compensation is performed for each of the shift command and the torque command, but at least a part of any one of the delay compensation may be omitted. Further, only one of the shift command and the torque command may be output after being compensated for delay. For example, when the response _dead time T _{d_cvt} of the continuously variable transmission 30 is always _longer than the response _dead time T _{d_eng} of the engine 10, the response _dead time T _{d_eng} of the engine 10 may be _set to zero. Further, when the response time constant T _CVT of the continuously variable transmission 30 is always larger than the response time constant T _eng of the engine 10, the response time constant T _eng of the engine 10 may be set to zero.

On the other hand, if the response dead time _{T D_eng} of the engine 10 is always greater than the response dead time _{T D_cvt} of the continuously variable transmission 30, the response dead time _{T D_cvt} of the continuously variable transmission 30 may be zero. Further, when the response time constant _{T eng} of the engine 10 is always greater than the response time constant _{T CVT} of the continuously variable transmission 30, the response time constant _{T CVT} of the continuously variable transmission 30 may be zero.

  As described above, the vehicle control system according to the present invention is useful for improving the fuel consumption of a vehicle that performs engine torque control and automatic transmission shift control, and in particular, the operating point of the engine changes to the target operating point. Suitable for dynamic fuel efficiency improvement in the process.

1-1 Vehicle Control System 1 Vehicle 10 Engine 15 Throttle Position Sensor 30 Continuously Variable Transmission 40 Hydraulic Control Device 41 Vehicle Speed Sensor 50 ECU
56 CVT shift response compensator 57 Engine torque response compensator Ne1 Target engine speed Te1 Target engine torque T _eng Engine response time constant T _{d_eng} Engine response _dead time T _CVT continuously variable transmission response time constant T _{d_cvt} None Speed change response time

Claims (5)

An engine, and an automatic transmission that transmits power output from the engine to driving wheels of a vehicle,
A target torque of the engine and a target gear ratio of the automatic transmission are determined based on a predetermined operating line indicating a relationship between the output torque of the engine and the rotational speed and a target value related to the acceleration of the vehicle. And at least one of a torque command, which is a command for realizing the target torque in the engine, and a shift command, which is a command for realizing the target gear ratio, in the automatic transmission. Is possible,
In the process in which the operating point indicating the output torque and the rotational speed changes to the target operating point corresponding to the target torque and the target gear ratio, the delay compensation is more effective than the case where the delay compensation is not performed. Is a vehicle control system that suppresses the separation from the predetermined operation line. The vehicle control system according to claim 1, wherein the predetermined operation line indicates a relationship between the output torque at which the engine can be operated with optimum fuel consumption and the rotation speed. The vehicle according to claim 1, wherein the vehicle control system performs the delay compensation based on at least one of a response delay to the torque command of the engine and a response delay to the shift command of the automatic transmission. Control system. The vehicle according to any one of claims 1 to 3, wherein the vehicle control system performs the delay compensation so that the operating point becomes an operating point on the predetermined operating line in a process of changing to the target operating point. Control system. The vehicle control system determines a target value related to the acceleration based on an operation amount of an operation member operated by a driver.
The determination as to whether or not to perform the delay compensation is made based on at least one of the magnitude of the target value related to the acceleration and the magnitude of the change speed of the target value related to the acceleration. The vehicle control system according to item.

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