KR20230006701A - System and method for vehicle shift control - Google Patents

Abstract

Disclosed are a system for vehicle shift control and a method thereof. According to an embodiment of the present invention, the system for vehicle shift control, which secures a start response through torque return control during power off up shift and thus improves a sense of acceleration delay, includes: a driving information detection unit which detects driving information measured by various sensors according to driving of a vehicle; a transmission control unit (TCU) which starts torque intervention control when an accel pedal stroke (APS), in which an intention of acceleration of a driver is reflected, is approved by the driving information detection unit during the power off up shift; and a control unit which shortens and ends an end point of the power off up shift before finishing the torque intervention control through the TCU, starts kick down shift, changes a torque return control subject into the control unit in case of a condition that a torque jump occurs, and performs stable torque return control, so that a transmission input torque after starting of the torque intervention control is not rapidly changed into a transmission input torque before the torque intervention control.

Description

Vehicle shift control system and method thereof {SYSTEM AND METHOD FOR VEHICLE SHIFT CONTROL}

The present invention relates to a vehicle shift control system and method thereof, and more particularly, to a vehicle shift control system and method for improving start response through torque return control at the end of a power-off shift.

In general, a vehicle using a multi-speed transmission (Automatic Transmission/Dual Clutch Transmission, AT/DCT) performs shifting under various driving conditions in order to secure a shift feeling according to a driver's will change while driving.

When an acceleration pedal stroke (APS) is applied by a driver's intention to accelerate during a power off up shift, the required transmission torque increases accordingly. In addition, the vehicle performs torque reduction to secure a shift feel, and strives to perform stable shifting and control the return of torque to the input required torque.

At this time, if the torque return time of the vehicle is too short, a sense of heterogeneity occurs in drivability due to shift shock or jerk due to rapid torque change.

Conversely, if the torque return time of the vehicle is too long, the drivability problem can be solved, but the transmission control unit (TCU) continuously performs the corresponding shift control, resulting in poor start (acceleration) response. That is, if the torque return time is controlled short, a problem occurs in drivability, and if the torque return time is controlled long, it takes a long time to satisfy the driver's will to accelerate with the continuous kick-down shift of the TCU, resulting in a sense of acceleration delay. There is a trade-off relationship that arises.

Therefore, in order to secure sufficient drivability at the time of torque return control of the vehicle, there is an unavoidable problem of sacrifice in terms of start response.

Matters described in this background art section are prepared to enhance understanding of the background of the invention, and may include matters that are not prior art already known to those skilled in the art to which this technique belongs.

An embodiment of the present invention determines when the torque return control of the TCU ends according to the driver's will to accelerate when the vehicle powers off-upshifts, and performs the torque return control with the control unit as the main body to enter kick-down shift by reducing the TCU shift control time. It is intended to provide a vehicle shift control system and method for improving start delay by advancing the timing.

According to one aspect of the present invention, a vehicle shift control system that secures start response through torque return control during a power off up shift detects driving information measured by various sensors according to vehicle operation. a driving information detection unit; A TCU (Transmission Control Unit) that starts torque intervention control when an APS (Accel Pedal Stroke) On signal reflecting the driver's will to accelerate is applied to the tip-in from the driving information detection unit during power-off up-shift ; And before torque intervention control is completed through the TCU, the power-off upshift end time is shortened and terminated, and kick-down shift is started, but under the condition that a torque jump occurs, the torque return control subject is changed to itself, so that after starting torque intervention control and a control unit that performs stable torque return control so that the transmission input torque does not suddenly change to the transmission input torque prior to the torque intervention control.

In addition, the controller may be configured as an engine management system (EMS) in the case of an internal combustion engine vehicle or a hybrid control unit (HCU) in the case of a hybrid vehicle.

The driving information detection unit may detect driving information measured from at least one of a vehicle speed sensor, an engine speed sensor, an accelerator pedal position sensor, a brake pedal position sensor, and a shift stage sensor.

Also, the control unit may determine that the torque jump occurs when a difference between the transmission input torque before the torque intervention control and the transmission input torque after the start of the torque intervention exceeds a predetermined value.

In addition, when the control unit determines that the torque jump occurs condition, the control unit changes the torque return control subject from the TCU to itself, and uses a torque return slope derived by using a gear stage and a shift phase as a control factor. can control.

On the other hand, according to one aspect of the present invention, a vehicle shift control method in which a control unit of a vehicle secures start response through torque return control during power off up shift, a) power off up shift (power off up shift) Detecting an Accel Pedal Stroke (APS) On signal reflecting a driver's will to accelerate through a driving information detector during Off Up Shift; b) starting torque intervention control through a transmission control unit (TCU) and determining an end point of the power-off upshift; c) shortening and terminating the power-off-up shift end point before completion of the torque intervention control through the TCU and starting a kick-down shift; and d) When it is determined that the torque jump occurs at the end of the power-off shift, the torque control subject is changed to itself so that the transmission input torque does not suddenly change to the transmission input torque before the torque intervention after the torque intervention control starts, so that the torque is returned stably. Performing control; includes.

The step c) may include determining that the torque jump occurs when a difference between the transmission input torque before the torque intervention control and the transmission input torque after the start of the torque intervention exceeds a predetermined value.

Also, step d) may include performing the torque return control using a torque return slope derived using a gear stage and a shift phase as a control factor.

In addition, in the shift phase of the torque return control, the torque return slope may be set higher in a kick-down shift condition in which the driver's will to accelerate is determined to be greater than normal acceleration.

After the step c), if the difference between the transmission input torque before the torque intervention control and the transmission input torque after the start of the torque intervention does not exceed a predetermined value, determining that the torque jump does not occur; and maintaining a torque return slope in the existing control by the TCU and terminating the shift control when the torque return is completed. Vehicle shift control method further comprising a.

According to an embodiment of the present invention, when APS is applied according to the driver's will to accelerate during power-off up-shift, the control unit shortens the power-off-up shift end point and advances kick-down shift, thereby improving the sense of acceleration delay and accelerating response There is an effect that can secure the castle.

In addition, when the power-off-up shift end point is shortened, a stable torque return slope is set using the gear stage and shift phase as control factors, thereby preventing shift shock due to torque jump prevention.

In addition, the effect of improving customer satisfaction without additional cost can be expected by improving the start response through rapid torque return control during power-off upshift of the automatic transmission only by upgrading the software without adding hardware to new and existing vehicles.

1 is a graph illustrating a conventional control method when a driver operates an accelerator pedal during a power-off upshift and a situation in which a problem occurs.
2 schematically shows the configuration of a vehicle shift control system according to an embodiment of the present invention.
FIG. 3 is a graph illustrating a method for improving oscillation response through torque return control when a power-off-up shift ends according to an embodiment of the present invention.
4 is a flowchart illustrating a vehicle shift control method for performing a torque intervention return control algorithm according to an embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings, embodiments of the present invention will be described in detail so that those skilled in the art can easily carry out the present invention.

The terminology used herein is for the purpose of describing specific embodiments only and is not intended to limit the present invention. As used herein, the singular forms are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprise" and/or "comprising", when used herein, specify the presence of recited features, integers, steps, operations, components and/or components, but It will also be understood that does not exclude the presence or addition of one or more of the features, integers, steps, acts, elements, components and/or groups thereof. As used herein, the term "and/or" includes any one or all combinations of the associated listed items.

As used herein, terms such as “vehicle” or “vehicle” or other similar terms refer to cars, buses, trucks, various commercial vehicles, including sport utility vehicles (SUVs) as well as rail vehicles. It is understood to include vehicles.

Throughout the specification, terms such as first, second, A, B, (a), (b), etc. may be used to describe various components, but the components should not be limited by the terms. These terms are only used to distinguish the component from other components, and the nature, order, or order of the corresponding component is not limited by the term.

Throughout the specification, when a component is referred to as being 'connected' or 'connected' to another component, it may be directly connected or connected to the other component, but there may be other components in the middle. It should be understood that it may be On the other hand, when a component is referred to as 'directly connected' or 'directly connected' to another component, it should be understood that no other component exists in the middle.

Additionally, it is understood that one or more of the methods or aspects thereof below may be executed by at least one or more controllers. The term “controller” may refer to a hardware device that includes memory and a processor. The memory is configured to store program instructions and the processor is specially programmed to execute the program instructions to perform one or more processes described in more detail below. A controller, as described herein, may control the operation of units, modules, components, devices, or the like. It is also understood that the methods below may be practiced by an apparatus that includes a controller along with one or more other components, as will be appreciated by those skilled in the art.

In addition, the controller of the present disclosure may be implemented as a non-transitory computer-readable recording medium including executable program instructions executed by a processor. Examples of computer-readable recording media include ROM, RAM, compact disk ROM, magnetic tapes, floppy disks, flash drives, smart cards, and optical data storage devices. It is not limited to this. The computer readable recording medium may also be distributed throughout a computer network to store and execute program instructions in a distributed manner, such as, for example, a telematics server or a controller area network (CAN).

Now, a vehicle shift control system and method according to an embodiment of the present invention will be described in detail with reference to the drawings.

Prior to a full-fledged description of the present invention, a situation in which a problem occurs in torque return control at the end of a conventional power-off shift will be described in more detail with reference to FIG. 1 .

1 is a graph illustrating a conventional control method when a driver operates an accelerator pedal during a power-off upshift and a situation in which a problem occurs.

Referring to FIG. 1(A), a state in which a driver applies an Accel Pedal Stroke (APS) for acceleration during a power off up shift of a vehicle is shown.

Conventionally, torque intervention control is performed to stably perform a power-off upshift of a vehicle. At this time, the input torque of the transmission after the intervention that is actually input to the transmission minimizes the amount of variation until the shift to the target stage is completed. During this control, the driver cannot feel a sense of acceleration.

In addition, torque return control should be performed on the transmission input torque after the vehicle shifts to the target stage after the intervention to the transmission input torque before the intervention. (Side Effect) Problems may occur.

First, when the return behavior of the transmission input torque is greatly controlled after the intervention, there is no sense of acceleration due to the intervention, and then the vehicle suddenly jumps out (that is, the sense of rapid acceleration) can be felt.

Second, when referring to FIG. 1(B), in order to solve the first problem, if the return behavior of the transmission input torque is gently controlled after the intervention, the bumpy feeling can be alleviated, but the torque jumps at the end of the power-off shift. shift shock caused by

Due to these problems, a sense of acceleration delay occurs when APS is applied during power-off upshift of the vehicle, and if the amount of APS applied by the driver is sufficiently large, kick-down control is continuously performed, and after the kick-down shift, the acceleration feeling reflecting the will to accelerate Since this is formed, the driver feels a considerably long acceleration delay.

Therefore, according to the present invention, the controller of the vehicle determines the end point of torque return control of the TCU according to the driver's will to accelerate during power-off upshift and performs torque return control accordingly, thereby reducing the TCU shift control time. An object of the present invention is to provide a vehicle shift control system and method for improving start delay by advancing.

2 schematically shows the configuration of a vehicle shift control system according to an embodiment of the present invention.

Referring to FIG. 2 , the vehicle shift control system 100 includes an engine 110, a transmission 120, a transmission control unit (TCU) 130, a driving information detector 140, and a controller 150. Here, the vehicle may be an internal combustion engine vehicle or a hybrid vehicle. The hybrid vehicle may further include a drive motor 161, a motor control unit (MCU) 162, a battery 163, a clutch 164, and a hybrid starter and generator (HSG) 165 indicated by dotted lines, , Since these are well-known techniques, detailed descriptions are omitted.

The engine 110 is a power source that converts thermal energy resulting from combustion of fuel into mechanical energy, and outputs driving force in an on-start state. The engine 110 may be a gasoline or diesel engine, and the output is controlled to an optimal operating point according to the driver's acceleration/deceleration control.

The transmission 120 is an automated multi-speed transmission and is composed of an automatic transmission (AT) or a dual clutch transmission (DCT).

The transmission 120 outputs the driving force of the engine 110 to the driving wheels by selecting an arbitrary gear stage according to driving information such as vehicle speed and accelerator pedal operation signal (Accel Pedal Stroke, APS) detected according to vehicle operation. keep driving

The TCU 130 automatically controls the target gear range of the transmission 120 determined according to conditions such as vehicle speed, APS (throttle opening), and input torque collected from the driving information to maintain a vehicle speed suitable for current driving conditions. .

The TCU 130 may control shifting through hydraulic control of a corresponding operation element and friction element set to correspond to a target shift stage different from the applied input torque.

The TCU 130 performs torque intervention control to stably perform the conventional power-off-up shift control when the driver's will to accelerate is applied while the vehicle is power-off-up-shifting.

The TCU 130 may perform kick-down shift control according to the APS condition in which the driver's will to accelerate is reflected.

The driving information detection unit 140 collects driving information measured by various sensors while driving the vehicle and transmits the collected driving information to the control unit 150 .

For example, the driving information detector 140 includes a vehicle speed sensor for detecting vehicle speed, an engine speed sensor for detecting engine speed, an accelerator pedal position sensor for detecting an accelerator pedal position value (APS), and a brake Detects driving information measured from at least one of a brake pedal sensor that detects the pedal position value (Brake pedal stroke, BPS) and a transmission position sensor (TPS) that detects the current shift stage can do. In addition, the embodiment of the present invention is not limited thereto, but in the case of a vehicle without the accelerator pedal sensor, the throttle opening degree of the throttle opening sensor detecting the opening degree of the throttle valve operating in conjunction with the accelerator pedal is detected and replaced with the APS. can be used as a control factor. Here, APS and BPS may have a position value of 100% when each pedal is completely pressed by a driver and a position value of 0% when not pressed.

The driving information detection unit 140 may detect the driver's start acceleration request and kick-down shift request based on the APS measured by the driver's accelerator pedal operation, and transmit the detected request to the control unit 150 .

The control unit 150 is a computing system that controls the overall operation for improving the start response through torque return control when the power-off up-shift of the vehicle shift control system 100 according to an embodiment of the present invention is completed.

The controller 150 may be configured as an upper controller that stores at least one program and data for shift control of a vehicle according to an embodiment of the present invention and executes the program to control a lower controller including the TCU 130. there is. For example, the control unit 150 may be configured as an EMS/ECU (Engine Management System/Electronic Control Unit) in the case of an internal combustion engine vehicle or a Hybrid Control Unit (HCU) in the case of a hybrid vehicle.

FIG. 3 is a graph illustrating a method for improving oscillation response through torque return control when a power-off-up shift ends according to an embodiment of the present invention.

Referring to FIG. 3, as in the conventional FIG. 1(A), the driver operates the accelerator pedal to overcome the acceleration delay in the existing control under the same driving conditions when the APS is applied during power-off upshift, and the start responsiveness It shows the torque intervention return time compensation control method to improve .

If the driver applies the APS On signal for re-acceleration during the power-off up shift control that occurs under the condition that the driver releases the accelerator pedal and turns off the APS, the TCU 130 performs the control of the existing shift control. To ensure stability, torque intervention control is started, and after the torque intervention control is started (ie, during intervention control), the transmission input torque is controlled to meet the transmission input torque before the intervention, and then the power-off upshift control is terminated, When the applied amount of the APS satisfies the kickdown shift condition, an acceleration delay occurs when the kickdown shift is performed to continuously reflect the driver's will to accelerate.

If the power-off upshift end point is shortened from ② to ① in order to simply improve the sense of acceleration delay, the torque intervention control is started at the end of the power-off shift, and then the transmission input torque is input before the torque intervention control. There is a side effect that shift shock occurs due to a torque jump in which torque rapidly changes. If the return slope of the intervention torque is increased in order to prevent the torque jump, the driver cannot help but feel a sense of bumping in acceleration due to the resultant torque behavior.

In order to solve this problem, the vehicle shift control system 100 advances the power-off upshift end point from ② to ① while maintaining the same interventional torque return slope through the TCU 130 as the conventional shift control and shortens the time. However, torque return control is performed through the control unit 150 so that the transmission input torque after the start of the torque intervention control does not suddenly change to the transmission input torque before the torque intervention control. Here, in the state, the power-off-up shift end time ① may be set by a shift feel developer. For example, even if the torque increases due to the engagement hydraulic pressure being significantly engaged, the transmission input speed and the speed at the target end are not synchronized due to occurrence of asynchronous occurrence. It can be set to an optimal point where the loosening phenomenon does not occur.

Hereinafter, the control unit 150 that controls the overall operation of the vehicle shift control system 100 according to an embodiment of the present invention will be described as the main subject.

The control unit 150 advances and shortens the end point of the power-off shift through the TCU 130, and adjusts the torque return slope in the existing power-off-up shift control so that no bump due to transmission input torque behavior occurs after the intervention control starts. keep

At this time, since the end point of the power-off-up shift is advanced from ② to ① in a situation where the torque return slope is the same as the existing control, the shift shock caused by the torque jump described in FIG. 1(B) should be improved. In this case, the control unit 150 according to an embodiment of the present invention changes the torque control subject from the TCU 130 to itself and performs torque return control. In other words, the upper controller 150 shortens the power-off-up shift end point of the lower controller TCU 130 according to the driver's re-acceleration request during the power-off up-shift and advances the kick-down shift accordingly to improve acceleration responsiveness. In the meantime, the torque control authority of the TCU 130 is taken over (or assisted), and a kind of cooperative control that stably performs torque return control is performed.

As such, the control unit 150 performs torque return control by changing the subject of torque control, thereby preventing shift shock due to torque jump, shortening the power-off upshift end point, and advancing kickdown shift accordingly.

Accordingly, as a result, the timing at which the driver's acceleration will be reflected is moved forward from the conventional ② to the present invention ①, thereby overcoming the sense of acceleration delay and improving the start responsiveness.

Meanwhile, the control unit 150 may be implemented with one or more processors that operate according to a set program, and the set program is a vehicle shift control method for improving start responsiveness at the end of power-off upshift according to an embodiment of the present invention. Each can be programmed to perform each step.

A vehicle shift control method for improving start response at the end of power-off shifting will be described in more detail with reference to the drawings below.

4 is a flowchart illustrating a vehicle shift control method for performing a torque intervention return control algorithm according to an embodiment of the present invention.

Referring to FIG. 4 , the control unit 150 of the vehicle shift control system 100 detects the tip-in of the driver through the driving information detector 140 during the power off up shift of the vehicle. APS On application according to acceleration intention is detected (S110).

The control unit 150 starts the torque intervention control through the TCU 130 and determines the end point of the power-off upshift (S120).

The control unit 150 shortens and terminates the end point of the power-off shift before completing the torque intervention control through the TCU 130 and starts kick-down shift, but determines whether a torque jump occurs at the end of the power-off shift. Determine (S130).

For example, the controller 150 determines that the torque jump does not occur when the difference between the transmission input torque before the torque intervention control and the transmission input torque after the start of the torque intervention control does not exceed a predetermined value (Cal) (S130; No). do.

At this time, after the start of the torque intervention control by the TCU 130, the control unit 150 maintains the torque return slope in the existing control so that no bump due to the input torque behavior of the transmission occurs, and controls the corresponding shift when the torque return is completed. can end (S140). The constant value may be set through a predetermined algorithm (eg, a program and a probability model) by performing experiments and learning.

On the other hand, if the difference between the transmission input torque before the torque intervention control and the transmission input torque after the torque intervention control exceeds a predetermined value (Cal) (S130; Yes), the control unit 150 determines that the torque jump occurs. .

When the control unit 150 determines that the torque jump occurs, the control unit 150 changes the torque return control subject from the TCU 130 to itself, and uses the torque return slope derived by using the gear stage and shift phase as control factors. Torque return is controlled (S150).

At this time, the reason why the gear stage and the shift phase are used as control factors is that the amount of acceleration change according to the transmission input torque behavior is different for each gear stage. is to set

In addition, during the torque return control by the control unit 150, the shift phase is set to have a larger torque return slope under conditions where it can be determined that the driver's will to accelerate is greater than normal acceleration, such as kick-down shift. It is possible to quickly satisfy the driver's will to accelerate and secure optimal start/acceleration response.

Thereafter, the control unit 150 may end the shift control when the torque return is completed.

As described above, according to an embodiment of the present invention, when APS is applied by the driver's will to accelerate during power-off up-shift, the control unit as the main agent shortens the power-off-up shift end point and advances kick-down shift, thereby improving the sense of acceleration delay It has the effect of securing acceleration response.

In addition, when the power-off-up shift end point is shortened, a stable torque return slope is set using the gear stage and shift phase as control factors, thereby preventing shift shock due to torque jump prevention.

In addition, the effect of improving customer satisfaction without additional cost can be expected by improving the start response through rapid torque return control during power-off upshift of the automatic transmission only by upgrading the software without adding hardware to new and existing vehicles.

Embodiments of the present invention are not implemented only through the devices and/or methods described above, and may be implemented through a program for realizing functions corresponding to the configuration of the embodiments of the present invention, a recording medium on which the program is recorded, and the like. Also, such an implementation can be easily implemented by an expert in the technical field to which the present invention belongs based on the description of the above-described embodiment.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concept of the present invention defined in the following claims are also included in the scope of the present invention. that fall within the scope of the right.

100: vehicle shift control system
110: engine
120: transmission
130: TCU
140: driving information detection unit
140: control unit

Claims (10)

In a vehicle shift control system that secures oscillation response through torque return control during power off up shift,
a driving information detection unit that detects driving information measured by various sensors according to vehicle operation;
A TCU (Transmission Control Unit) that starts torque intervention control when an APS (Accel Pedal Stroke) On signal reflecting the driver's will to accelerate is applied to the tip-in from the driving information detector during power-off up-shift ; and
Before torque intervention control is completed through the TCU, the power-off upshift end point is shortened and terminated, and kick-down shift is started, but when a torque jump occurs, the transmission after starting torque intervention control by changing the subject of torque return control to itself a controller that performs stable torque return control so that the input torque does not suddenly change to the transmission input torque prior to the torque intervention control;
Vehicle shift control system comprising a. According to claim 1,
The control unit
A vehicle shift control system composed of an EMS (Engine Management System) in the case of an internal combustion engine vehicle or a Hybrid Control Unit (HCU) in the case of a hybrid vehicle. According to claim 1,
The driving information detection unit
A vehicle shift control system for detecting driving information measured from at least one of a vehicle speed sensor, an engine speed sensor, an accelerator pedal position sensor, a brake pedal position sensor, and a shift stage sensor. According to claim 1,
The control unit
The vehicle shift control system determining that the torque jump occurs when a difference between the transmission input torque before the torque intervention control and the transmission input torque after the start of the torque intervention exceeds a predetermined value. According to any one of claims 1 to 4,
The control unit
When determining the condition in which the torque jump occurs, the torque return control subject is changed from the TCU to itself, and the torque return is controlled using a torque return slope derived by using a gear stage and a shift phase as a control factor Vehicle shifting control system. A vehicle shift control method in which a control unit of a vehicle secures start response through torque return control during a power off up shift, the method comprising:
a) detecting an Accel Pedal Stroke (APS) On signal reflecting the driver's will to accelerate through a driving information detector during a power off up shift;
b) starting torque intervention control through a transmission control unit (TCU) and determining an end point of the power-off upshift;
c) shortening and terminating the power-off-up shift end point before completion of the torque intervention control through the TCU, and starting a kick-down shift; and
d) When it is determined that the torque jump occurs at the end of the power-off shift, the torque control subject is changed to itself so that the transmission input torque does not suddenly change to the transmission input torque before the torque intervention after the torque intervention control starts, and the torque return control is stable. performing;
Vehicle shift control method comprising a. According to claim 6,
In step c),
and determining that the torque jump occurs when a difference between the transmission input torque before the torque intervention control and the transmission input torque after the start of the torque intervention exceeds a predetermined value. According to claim 6,
In step d),
and performing the torque return control using a torque return slope derived using a gear stage and a shift phase as a control factor. According to claim 8,
In the shift phase of the torque return control, the vehicle shift control method sets a larger torque return slope in a kick-down shift condition in which the driver's will to accelerate is determined to be greater than normal acceleration. According to any one of claims 6 to 9,
After step c),
determining that the torque jump does not occur when a difference between the transmission input torque before the torque intervention control and the transmission input torque after the start of the torque intervention does not exceed a predetermined value; and
maintaining a torque return slope in the existing control by the TCU and terminating the shift control when the torque return is completed;
Vehicle shift control method further comprising a.

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