KR101048139B1 - Method and device for deceleration control of automatic transmission car - Google Patents

Abstract

A deceleration control method for an automobile equipped with an automatic transmission having a damper clutch, the method comprising: determining whether a coasting deceleration direct connection condition is satisfied when a vehicle driving state is in a deceleration non-direct connection state; Determining whether the reduced deceleration direct hydraulic condition is satisfied; when the set deceleration direct hydraulic condition is satisfied, controlling the damper clutch to the deceleration direct connection state. And a step of performing fuel cutoff control when the fuel cutoff condition is satisfied.

Automatic Transmission, Lift Foot Up (LFU), Damper Clutch, Fuel Cutoff

Description

METHOD AND APPARATUS FOR CONTROLLING A VEHICLE EQUIPPED WITH AN AUTOMATIC TRANSMISSION UNDER DECELERATION}

The present invention relates to a vehicle, and more particularly, to a deceleration control method and apparatus for an automatic transmission vehicle.

In general, an automatic transmission vehicle automatically shifts to an appropriate shift stage according to the driving state of the vehicle. To this end, various driving state variables are introduced, and various algorithms for improving fuel economy have been adopted. For example, the damper clutch may be operated or fuel may be shut off under certain conditions.

However, as the various algorithms for a particular effect are complicatedly interrelated, undesirable phenomena may occur in the control state of the transmission and the engine as a whole.

For example, in the lift-foot up state, the damper clutch is operated to improve fuel efficiency. In some cases, the damper clutch is operated to supply hydraulic pressure to the damper clutch. The hydraulic pressure is released when the hydraulic duty limit is reached. At this time, the hydraulic pressure is repeatedly supplied because the damper clutch operating condition is still satisfied. In this case, the engine speed (or turbine speed) is periodically fluctuated, which not only reduces the driving quality of the vehicle but also causes anxiety for the driver.

As another example, when the damper clutch is not operating conditions, fuel consumption may be improved by cutting off fuel while the engine speed is lowered. In this process, when the engine speed reaches the set speed, the fuel is re-supplied, When the damper clutch is synchronized, the difference in the target speed is so large that the engine speed suddenly increases. In this situation, the damper clutch is not in operation, so it is not transmitted to the driver as the vibration of the car, but the very unstable driving state is transmitted to the driver through the tachometer on the instrument panel, which not only degrades the driving quality of the car but also causes the driver anxiety. Will be done.

SUMMARY OF THE INVENTION The present invention has been made in an effort to provide a deceleration control method and apparatus for an automatic transmission vehicle capable of resolving phenomenal instability resulting from various control algorithms during deceleration.

In order to achieve the above technical problem, a deceleration control apparatus for an automatic transmission vehicle of one embodiment of the present invention is a control apparatus for deceleration of a vehicle having an automatic transmission with an damper clutch and an engine, and detects a driving state of the automobile. And an electronic control unit for controlling the automatic transmission and the engine based on the driving state of the vehicle detected by the driving state detection unit, wherein the electronic control unit is one of the aspects of the present invention. Characterized in that a series of commands for performing the deceleration control method of the automatic transmission vehicle.

The set deceleration direct hydraulic condition includes: calculating a damper clutch target oil pressure for the automatic transmission to decelerate directly; determining whether the damper clutch target oil pressure is greater than a set duty limit value, wherein the target oil pressure is the set duty limit value. If it is not greater than, it can be determined that the set deceleration direct-pressure hydraulic condition is satisfied.

The damper clutch target hydraulic pressure may be calculated from a predetermined map based on a target engine speed and engine torque when the damper clutch is directly connected.

If the coasting deceleration direct connection conditions are not satisfied, the method may further include performing the set fuel control.

If the target hydraulic pressure is larger than the set duty limit value, it may further comprise the step of performing the set fuel control.

The set fuel control may include: determining whether a fuel cutoff condition is satisfied; shutting off fuel of the injector when the fuel cutoff condition is satisfied; when the fuel of the injector is cut off, the fuel is changed according to the current engine speed; And determining whether the supply condition is satisfied.

When the current engine speed is satisfied that the damper clutch is directly connected to the target engine speed when the damper clutch is directly connected to be lower than the set deviation and the current engine speed is reduced by more than the set change rate, the current engine speed is set to the fuel resupply rotation speed Even in this case, it can be determined that the resupply condition of the fuel is satisfied.

As described above, according to the deceleration control method and apparatus of an automatic transmission vehicle according to an embodiment of the present invention, in determining whether to operate the damper clutch in the driving state of the decelerating vehicle to determine the hydraulic pressure to be supplied to the damper clutch in advance By determining whether or not the hydraulic pressure is supplied, instability due to the repetition of the hydraulic pressure supply and release can be eliminated.

In addition, when the damper clutch is decelerated while the damper clutch is not in operation, the engine speed can be prevented from rapidly turning to the target speed when the engine speed is too low for the desired target speed, thereby improving driving quality. have.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram of a deceleration control apparatus for an automatic transmission vehicle according to an embodiment of the present invention.

As shown in FIG. 1, a deceleration control apparatus for an automatic transmission vehicle according to an exemplary embodiment of the present invention includes a driving state detection unit 150 for detecting a driving state of a vehicle and a driving state detection unit 150. An electronic control unit 100 (hereinafter referred to as ECU) for controlling the automatic transmission 130 and the engine 120 based on the driving state of the vehicle.

The driving state detection unit 150 includes an engine speed detector 155 for detecting an engine speed Ne, a turbine speed detector 160 for detecting a turbine speed of the automatic transmission 130, and an engine 120. Throttle opening degree detector 165 for detecting the throttle opening amount of the vehicle), and a vehicle speed detector 170 for detecting the vehicle speed of the vehicle.

The engine 120 includes a fuel injector 125 for supplying fuel to the engine 120, and the automatic transmission 130 includes a damper clutch 135 and an actuator unit 140 for controlling the damper clutch 135. Is provided. The actuator unit 140 may be formed of, for example, a solenoid valve. The electronic control unit 100 controls the engine 120 by controlling the fuel injector 125 and also controls the operation of the damper clutch 135 of the automatic transmission 130 by controlling the actuator unit 140. Done.

The ECU 100 may be implemented as one or more microprocessors operated by a set program, and the set program may be configured to perform each step included in the deceleration control method of the automatic transmission vehicle according to the embodiment of the present invention described below. It can be a series of instructions.

Hereinafter, a deceleration control method of an automatic transmission vehicle according to an embodiment of the present invention will be described in detail with reference to FIG. 2.

2 is a flowchart illustrating a deceleration control method of an automatic transmission vehicle according to an exemplary embodiment of the present invention.

First, the ECU 100 determines whether the driving state of the vehicle is in the non-deceleration direct connection state (S210), and in the case of the deceleration non-direct connection state, determines whether the coasting (coasting) deceleration direct connection condition is satisfied (S215).

The deceleration non-direct connection state refers to a state in which the damper clutch 135 of the automatic transmission 130 is not directly connected in a state where the vehicle is decelerating. The decelerating state refers to a state in which the vehicle decelerates slowly by depressing the brake or gradually decelerates as the vehicle inertia travels by not pressing the accelerator pedal.

Since it is already attempted to control the automatic transmission by directly connecting the damper clutch during inertia driving, the coasting deceleration direct connection condition for this can be any condition known to those skilled in the art.

When the coasting deceleration direct connection condition is satisfied, the ECU 100 determines whether the set deceleration direct pressure condition is satisfied (S220).

In step S220, the ECU 100 calculates a damper clutch target oil pressure for the automatic transmission 130 to be decelerated directly (S225), and the damper clutch target oil pressure. It is determined whether it is greater than the set duty limit value (S230). If the target hydraulic pressure is not greater than the set duty limit value, the determination step S230 determines that the set deceleration direct pressure condition is satisfied, and if the target hydraulic pressure is greater than the set duty limit value, the set deceleration direct pressure condition. It is determined that this is not satisfied.

Specifically, in order to directly connect the damper clutch 135, the hydraulic pressure must be supplied to the damper clutch 135. As such, the target hydraulic pressure required for the direct connection of the damper clutch 135 is the engine speed Ne and the engine. The torque TQ may vary depending on the driving state of the vehicle. In the exemplary embodiment of the present invention, the target hydraulic pressure is calculated from a preset map based on the target engine speed (target Ne) and target engine torque (target TQ) when the damper clutch 135 of the automatic transmission 130 is directly connected. do. For example, the predetermined map may be defined by the following table.

In the embodiment of the present invention, for example, the hydraulic pressure to be supplied to the damper clutch 135 is determined by the target engine speed (target Ne) and the target engine torque (target TQ), but the protection scope of the present invention is necessarily It should not be understood to be limited to this. It will be apparent to those skilled in the art that when the hydraulic pressure supplied for the direct connection of the damper clutch 135 is determined based on other parameters, it may be set as a map according to the parameters.

The map described in the above table is merely an example, and should not be understood that the protection scope of the present invention is limited to specific values thereof.

The target engine torque may be calculated based on the target engine speed (target Ne) and the throttle opening amount, but it is not necessarily limited thereto. If it is possible to calculate the engine torque by other variables, the technical spirit of the present invention in such a configuration can be easily applied by those skilled in the art.

When the set deceleration direct pressure hydraulic condition is satisfied, the ECU 100 controls the damper clutch 135 of the automatic transmission 130 to the deceleration direct connection state (S235). The ECU 100 may achieve a deceleration direct connection state of the damper clutch 135 by driving the actuator unit 140, which is known to those skilled in the art.

When the damper clutch 135 is controlled to the deceleration direct connection state, the ECU 100 determines whether the set fuel cutoff condition is satisfied (S240), and when the damper clutch 135 satisfies the fuel cutoff condition (S245). ).

The fuel cutoff condition refers to a condition for entering the fuel cutoff state at the time of deceleration when the damper clutch 135 is directly connected, and any conditions already known to those skilled in the art may be adopted. For example, the fuel cutoff condition may be that the current engine speed (currently Ne) is equal to or higher than the set engine speed.

The fuel cutoff control may, for example, merely shut off the fuel supplied to the fuel injector 125, and may employ various other specific fuel cut / release processes already known to those skilled in the art.

In the above, the conditions for controlling the damper clutch 135 in the direct connection state at coasting deceleration and the fuel cut process after the control have been described. Hereinafter, the fuel blocking and releasing process in a state in which the damper clutch 135 is not suitable to be controlled in a direct connection state will be described in detail with reference to FIG. 2.

When the coast deceleration direct connection condition is not satisfied in the step S215, the ECU 100 performs a fuel control process S260 described later. Further, even when the deceleration direct hydraulic pressure condition set in the step S220 is not satisfied, the ECU 100 performs the fuel control process S260 described later. More specifically, when the target hydraulic pressure is greater than the set duty limit value in the step (S230), it is to perform the set fuel control process (S260) without the above-described damper clutch deceleration direct control.

That is, when it is determined that it is not appropriate to enter the direct connection state while driving in the deceleration non-direct connection state, the ECU 100 performs the fuel control process S260 to thereby cut off the fuel in the non-direct connection state of the damper clutch 135. To control the release.

As the fuel control process (S260), first, the ECU 100 determines whether the set fuel cutoff condition is satisfied (S265), and when the fuel cutoff condition is satisfied, the fuel of the injector is cut off (S270). Regarding the entry into the fuel cut-off state, the above-described steps S240 and S245 may be referred to.

When the fuel of the injector is cut off, the ECU 100 determines whether the resupply condition of the blocked fuel is satisfied (S280). The fuel resupply conditions vary depending on the current engine speed (currently Ne).

First, the ECU 100 determines whether the current engine speed (current Ne) is equal to or less than the fuel resupply rotation speed Ne0 set to a constant (S283). In this determination, when the current engine speed (currently Ne) is less than or equal to the fuel resupply rotation speed Ne0, fuel is resupplied (S295).

By this determination process, when the engine speed is close to the idle speed, stable engine control is possible by re-fueling the fuel. However, when the engine speed is reached until the set fuel resupply speed Ne0 reaches the high target engine speed (that is, when the target engine speed is very high), the engine speed is the idle speed. In the state close to the high rotational speed occurs that can cause anxiety to the driver. Therefore, even when the engine speed does not reach the set fuel resupply rotation speed Ne0, it is preferable to improve the running quality of the automatic transmission vehicle by preventing the engine speed from suddenly rebounding in such a large manner.

Therefore, in the embodiment of the present invention, even if the current engine speed (currently Ne) does not reach the set fuel resupply rotation speed Ne0 in the step S283, the condition set based on the engine speed is Refill fuel when satisfied.

In more detail, the current engine speed (current Ne) is lower than a set deviation (eg 600 rpm) by more than a target engine speed (target Ne) when the damper clutch 135 is directly connected and the current engine speed. If the number (current Ne) is decreasing to the set change rate or more (that is, the time change rate of the current engine speed is less than or equal to the negative set change rate); when the current engine speed (current Ne) is set, Even when the resupply rotation speed Ne0 or more is determined, it is determined that the resupply condition of the fuel is satisfied.

To this end, the ECU 100 determines whether the current engine speed (currently Ne) is lower than a target deviation (eg, 600 rpm) by more than a target engine speed (target Ne) when the damper clutch 135 is directly connected (S286). In step S289, it is determined whether the current engine speed (currently Ne) is reduced to the set change rate dd or more (S289). When both of these conditions are satisfied, it is determined that the fuel resupply condition is satisfied.

When it is determined that the fuel resupply condition is satisfied according to the above process, the ECU 100 supplies the fuel to the engine 120 by controlling the fuel injector 125 (S295).

After the above step (S245) (S295) by proceeding to the above step (S215), the deceleration control method of the automatic transmission vehicle according to an embodiment of the present invention is repeatedly performed.

In the above, the present invention has been described with reference to the presently considered embodiments, but the present invention should not be construed as being limited to the above embodiments. Rather, it should be construed as including all modifications of the range which are easily changed by those skilled in the art from the above-described embodiment of the present invention and considered equivalent.

1 is a block diagram of a deceleration control apparatus for an automatic transmission vehicle according to an embodiment of the present invention.

2 is a flowchart illustrating a deceleration control method of an automatic transmission vehicle according to an exemplary embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

100: electronic control unit

120: engine

125: fuel injector

130: automatic transmission

135: damper clutch

140: actuator unit

150: driving state detection unit

155: engine speed detector

160: turbine speed detector

165: throttle opening degree detector

170: vehicle speed detector

Ne: engine speed

Ne0: Reload of fuel

TQ: Engine Torque

Target Ne: Target Engine Speed

Target TQ: Target Engine Torque

Current Ne: Current engine speed

Claims (14)

A deceleration control method for a vehicle equipped with an automatic transmission equipped with a damper clutch, Determining whether the coasting deceleration direct connection condition is satisfied when the vehicle driving state is the deceleration non-direct connection state. When the coasting deceleration direct connection condition is satisfied, determining whether the set deceleration direct connection hydraulic condition is satisfied. Controlling the damper clutch in a deceleration direct state when the set deceleration direct hydraulic condition is satisfied. Determining whether the fuel cutoff condition is satisfied when the fuel cell is controlled in the deceleration direct connection state; Performing fuel cutoff control when the fuel cutoff condition is satisfied; Deceleration control method of an automatic transmission vehicle comprising a. In claim 1, The set deceleration direct hydraulic condition is, Calculating a damper clutch target hydraulic pressure for the automatic transmission to be directly decelerated; Determining whether the damper clutch target hydraulic pressure is greater than a set duty limit value; If the target hydraulic pressure is not greater than the set duty limit value, the deceleration control method of the automatic transmission vehicle, characterized in that it is determined that the set deceleration direct-pressure hydraulic condition is satisfied. 3. The method of claim 2, And said damper clutch target hydraulic pressure is calculated from a predetermined map based on a target engine speed and engine torque when said damper clutch is directly connected to said damper clutch. In claim 1, If the coasting deceleration direct connection condition is not satisfied further comprising the step of performing the set fuel control, the deceleration control method of the automatic transmission vehicle. 3. The method of claim 2, And setting the fuel control when the target hydraulic pressure is greater than a set duty limit value. The method of claim 4 or 5, The set fuel control, Determining whether the fuel blocking condition is satisfied Cutting off fuel of the injector when the fuel blocking condition is satisfied; In the case where the fuel of the injector is cut off, determining whether a fuel resupply condition variable according to the current engine speed is satisfied. Deceleration control method of an automatic transmission vehicle comprising a. In claim 6, The current engine speed should be lower than the set deviation more than the target engine speed when the damper clutch is directly connected, and The engine speed should be decreasing more than the set rate of change. If it satisfies the deceleration control method of the automatic transmission vehicle, it is determined that the re-supply conditions of the fuel is satisfied even if the current engine speed is more than the set fuel resupply rotation speed. A control device for deceleration of an automobile provided with an automatic transmission and an engine provided with a damper clutch, A driving state detecting unit detecting a driving state of a vehicle; An electronic control unit for controlling the automatic transmission and the engine on the basis of the driving state of the vehicle detected from the driving state detection unit, The electronic control unit Determining whether the coasting deceleration direct connection condition is satisfied when the vehicle driving state is the deceleration non-direct connection state. When the coasting deceleration direct connection condition is satisfied, determining whether the set deceleration direct connection hydraulic condition is satisfied. Controlling the damper clutch in a deceleration direct state when the set deceleration direct hydraulic condition is satisfied. Determining whether the fuel cutoff condition is satisfied when the fuel cell is controlled in the deceleration direct connection state; Performing fuel cutoff control when the fuel cutoff condition is satisfied; A deceleration control apparatus for an automatic transmission vehicle, characterized in that for performing a series of commands for performing a deceleration control method for an automatic transmission vehicle comprising a. In claim 8, The set deceleration direct hydraulic condition is, Calculating a damper clutch target hydraulic pressure for the automatic transmission to be directly decelerated; Determining whether the damper clutch target hydraulic pressure is greater than a set duty limit value; If the target hydraulic pressure is not greater than the set duty limit value, the deceleration control apparatus for an automatic transmission vehicle, characterized in that it is determined that the set deceleration direct-pressure hydraulic condition is satisfied. The method of claim 9, And said damper clutch target hydraulic pressure is calculated from a predetermined map based on a target engine speed and engine torque when said damper clutch is directly connected. In claim 8, If the coasting deceleration direct connection condition is not satisfied further comprising the step of performing a set fuel control device of the automatic transmission vehicle characterized in that it further comprises. The method of claim 9, And setting the fuel control when the target hydraulic pressure is greater than the set duty limit value. The method of claim 11 or 12, The set fuel control, Determining whether the fuel blocking condition is satisfied Cutting off fuel of the injector when the fuel blocking condition is satisfied; In the case where the fuel of the injector is cut off, determining whether a fuel resupply condition variable according to the current engine speed is satisfied. Deceleration control device of an automatic transmission vehicle comprising a. The method of claim 13, The current engine speed should be lower than the set deviation more than the target engine speed when the damper clutch is directly connected, and The engine speed should be decreasing more than the set rate of change. If it satisfies the deceleration control apparatus of the automatic transmission vehicle, it is determined that the re-supply conditions of the fuel is satisfied even if the current engine speed is more than the set fuel resupply rotation speed.

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