KR0166616B1 - Bypass air flow control method for engine rpm down in idle - Google Patents

Abstract

The present invention is to counter the actual RPM target RPM + 50 RPM to control the total amount of bypass air flowing into the engine to increase the rotational speed of the Jenjin when the rotational speed of the engine is lowered below the target rotational speed of the engine idle Cioff is set to determine whether idle is off or Cioff is zero, and when idle is off or Cioff is zero, the entire bypass air amount (Ga ₁ ) is supplied to the engine and idle is not off or Cioff is If non-zero, determine if the RPM of the engine is down and if the RPM of the engine is down, CECONT (kg-h) = [(TMPGA * 0.903 / actual RPM (Ne))-ADV * CETNEB] / [1-ADV ], Where ADV = {(DCETNED * Ne / 0.903) -TIDGAN} / (0.5616-TIDGAN) * 0.906, where TMPGA = gb + gl + gsw-grec + gfb, ADV = first order progression correction sensitivity Coefficient, DCETNED = air flow simulation coefficient, TIDGAN = 1.5 seconds, using the equation of air compensation according to water temperature The CECONT is calculated by not counting, and the total bypass correction air amount (Ga ₂ ) is supplied to the engine to increase the engine RPM.

Description

How to control the total bypass air volume for engine speed down during idle

1 is a schematic block diagram of an idle speed control system.

2 is a flow chart of the overall bypass air volume control method for the engine speed down during idle of the vehicle according to the present invention.

* Explanation of symbols for main parts of the drawings

1: idle speed control valve 2: throttle valve

3: air flow meter 4: air cleaner

5: surge tank

The present invention relates to a method for controlling the total bypass air volume for engine revolution (RPM) down when the vehicle is idle, and more particularly, when the engine rotation speed is lowered below the target rotational speed during engine idle. The present invention relates to a method for controlling the total amount of bypass air flowing into the engine to increase the rotation speed.

Typically, gasoline engines used in automobiles control the output of the engine by adjusting the amount of air sucked into the engine by manipulating the opening of the throttle valve with an accelerometer. At idle driving of the vehicle, the throttle valve is closed, and therefore, the idle speed of the vehicle is determined by the air flowing into the engine through the gap and the bypass passage between the throttle body and the throttle valve. As described above, the air introduced into the engine contributes to the combustion of the fuel, and the idle speed is determined at a line in which the output by the combustion and the frictional force of the engine itself are parallel to each other.

Therefore, the idle speed of the engine changes as the frictional force of the engine changes with time or changes in the amount of inflowing air. If the idle speed is low, the engine will not run smoothly, and if it is too high, the fuel consumption will increase, and if the traffic is not well communicated, the idle speed will be as low as possible because most of the fuel consumption is at idle. It is preferable.

However, the idle speed must be maintained at a constant speed in any state of the engine, so that the engine must be controlled to operate smoothly. For example, the idle speed must remain constant, as in the no-load state, even when the car air conditioner is activated, the shift lever is in the drive position, or the power steering is at full power.

The target idle speed is determined in consideration of the coolant temperature of the ECU engine, whether the idle contact is opened or closed, the load of the car air conditioner, the load of the automatic transmission, the power load, etc. .

Accordingly, it is an object of the present invention to provide a method for controlling the total amount of bypass air flowing into an engine in order to increase the engine speed when the engine speed is lowered below the target speed during idling of the engine. .

The above object is to set a target engine RPM during idle of the vehicle, according to the present invention; Detecting an actual RPM of the engine at idle; Setting Cioff as a counter at actual RPM target RPM + 50 RPM; Determining whether idle is off or Cioff is zero; Supplying the entire bypass air amount Ga ₁ to the engine when idle is off or Cioff is zero; If idle is not off or Cioff is not zero, determining whether the RPM of the engine is down; If the RPM of the engine is down, calculating by counting CECONT for 1.5 seconds by the following equation; Supplying the entire bypass correction air amount (Ga ₂ ) to the engine to increase the RPM of the engine, CECONT (kg-h) = [(TMPGA * 0.903 / actual RPM (Ne))-ADV * CETNEB] / [1-ADV], where ADV = {(DCETNED * Ne / 0.903) -TIDGAN} / (0.5616-TIDGAN) 0.906, wherein

TMPGA = basic air volume (gb) + electric load correction air volume (gl) + air compensation amount at startup (gsw)-return air loss correction air amount (grec) + feedback air correction amount (gfb),

ADV = 1st order correction correction coefficient,

DCETNED = air flow simulation coefficient,

TIDGAN = the amount of air correction according to the water temperature is achieved by the total bypass air amount control method for the engine speed down during idle.

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

In the schematic block diagram of the idle speed control system shown in FIG. 1, the air passing through the air cleaner 4 in the state where the driver has not stepped on the accelerator pedal is idle because the throttle valve 2 is closed. (ISC, Idle Speed Control) flows into the surge tank through the valve (1). As described in the prior art, the rotation speed of the engine at idle driving is determined in accordance with the amount of air passing through the ISC valve 1. For example, when the air conditioner is operated, the opening degree of the ISC valve 1 is increased to further increase the amount of air flowing into the engine, thereby increasing the engine speed.

2 is a flowchart of a method for controlling the total bypass air volume for the engine speed down when the vehicle is idle according to the present invention. The target engine RPM is set in the ECU at idle (S1), and the engine at idle. The actual RPM of the controller is detected (S2), and the Cioff, a counting time for compensating the amount of air when the actual RPM falls above 50 RPM compared to the target RPM, is set in the ECU (S3). (S4), if the idle is off or Cioff is 0, the entire bypass air amount Ga ₁ bypassed through the ISC valve 1 without passing through the throttle valve 2 is supplied to the engine ( S5).

To obtain the total bypass air amount Ga ₁ , the total amount QA of the air flowing into the engine is obtained, and the QA detected by the air flow meter 3 is usually obtained by the following equation.

QA = Ga * Catp * Ctha-Qlck-Qlrn, where

Ga: total bypass air volume,

Catp: atmospheric pressure correction factor,

Ctha: intake temperature correction coefficient,

Qlck: lock prevention factor,

Qlrn: Learning correction factor, inputted to ECU.

The total bypass air volume (Ga ₁ ) when idle is off or Cioff is 0 is TMPGA + gdp, where TMPGA is gd + gl + gsw-grec + gfb,

From here,

gb: basic air volume,

gl: Load correction air volume when running electronics,

gsw: air compensation amount at start-up,

grec: return air loss correction air volume,

gfb: Feedback air correction amount.

The basic air amount gb is determined by an engine coolant temperature detection means or the like, and is a bypass air amount introduced through an ISC valve having an opening degree in accordance with a value input to the ECU during idle driving. gl is the amount of correction air that increases or decreases along the ISC valve with an opening according to the value input to the ECU to increase or decrease the engine speed during idle driving at the moment the air conditioner, headlamp and power steering are activated. gsw is an air compensation amount that is increased for a certain time after the initial cold start of the engine in order to improve the startability and the stability of the engine speed after starting. The amount of correction air to adjust the number. On the other hand, grec is the amount of air that compensates for the loss of the amount of air returned to the engine when the vehicle is suddenly decelerated, and is increased or decreased by an ISC valve having an opening degree according to the value input to the ECU.

On the other hand, if the idle is not off or Cioff is not 0 in step S4, the ECU determines whether the RPM of the engine is down at idle (S6), and if the RPM of the engine is down, CECONT is expressed by the following equation. Calculate by counting for 1.5 seconds (S7).

CECONT (kg-h) = [(TMPGA * 0.903 / actual RPM (Ne))-ADV * CETNEB] / [1-ADV], where ADV = {(DCETNED * Ne / 0.903) -TIDGAN} / (0.5616 -TIDGAN) 0.906, and in the above,

TMPGA = basic air volume (gb) + electric load correction air volume (gl) + air compensation amount at startup (gsw)-return air loss correction air amount (grec) + feedback air correction amount (gfb),

ADV = 1st order correction correction coefficient,

DCETNED = air flow simulation coefficient,

TIDGAN = air compensation amount according to water temperature. The ISC duty control value is calculated using the total bypass correction air amount Ga ₂ obtained by the above equation as QA, and the opening value of the ISC valve 1 is increased to supply the engine with the air amount according to the calculated duty control value. By correcting the air volume (S8), the RPM of the down engine is increased (S9).

The idle speed control duty value is defined as a percentage of total run time / actual drive time x 100, and the solenoid valve is actuated according to the duty value entered into the ECU.

According to the entire bypass air amount control method for the engine speed down when the vehicle idles, according to the present invention as described above, when the engine rotation speed is lowered below the target rotational speed, the engine speed increases By controlling the total amount of bypass air flowing into the engine in order to maintain the rotation speed of the engine at a constant speed in any state, the engine can be controlled to operate smoothly.

Claims (1)

Setting a target engine RPM when the vehicle is idle; Detecting an actual RPM of the engine at idle; Setting Cioff as a counter at actual RPM target RPM + 50 RPM; Determining whether idle is off or Cioff is zero; Supplying the entire bypass air amount Ga ₁ to the engine when idle is off or Cioff is zero; If idle is not off or Cioff is not zero, determining whether the RPM of the engine is down; If the RPM of the engine is down, calculating the CECONT by counting the CECONT for 1.5 seconds by the following equation; Supplying the total bypass correction air amount (Ga ₂ ) to the engine to increase the RPM of the engine, characterized in that the total bypass air amount control method for the engine speed down when the vehicle idle. CECONT (kg-h) = [(TMPGA * 0.903 / actual RPM (Ne))-ADV * CETNEB] / [1-ADV], where ADV = {(DCETNED * Ne / 0.903) -TIDGAN} / (0.5616 -TIDGAN) * 0.906, where TMPGA = gb + gl + gsw-grec + gfb, ADV = first order progress correction sensitivity coefficient, DCETNED = air flow simulation coefficient, TIDGAN = air correction amount according to water temperature.