KR20160046533A - Ignition Coil Charging Start Angle Control Method - Google Patents

Abstract

In the ignition coil charging start angle control method of the present invention: after ignition is conducted with the initial ignition charging time of an ignition coil, which is set, the difference between the target ignition angle and actual ignition angle is determined by an engine control unit (ECU); when a difference between the target ignition angle and actual ignition angle occurs, the initial ignition charging time is corrected with an ignition charging start time correction value for the difference value of the actual ignition angle, and the corrected ignition charging time is determined; the difference between the actual ignition angle and the target ignition angle due to a rapid change in RPMs is settled; and an accurate ignition angle control is always conducted even when there is a rapid change in the RPMs.

Description

{Ignition Coil Charging Start Angle Control Method}

FIELD OF THE INVENTION The present invention relates to ignition angle control, and more particularly, to an ignition coil charge start angle control method for precise ignition angle control when the actual ignition angle differs from the target ignition angle.

In general, the engine ignition timing is the most influential part of the engine, so it must be driven correctly.

To do this, the Tooth of a crank position sensor (CPS) in a predetermined angle unit is counted to output based on the calculated ignition angle, a timer is used, and a piston stroke Is synchronized with the operation of the crank position sensor so that the ignition timing is controlled at an angle with reference to a top dead center (TDC) of the crank position sensor.

Particularly, in a gasoline engine, ignition coil charging is required. When the charging time is over, the ignition is performed through the spark plug, so that the charging time is determined considering the cooling water temperature and the battery condition. The charge start angle is determined at the start of the star segment.

Korean Patent Publication No. 10-2003-0081680 (October 22, 2003)

However, the actual ignition angle differs from the target ignition angle when the engine speed (RPM) is abruptly changed by being influenced by the engine speed (RPM).

For example, when the engine RPM is rapidly increased, the actual ignition angle is delayed more than the target ignition angle. On the other hand, when the engine speed (RPM) is rapidly decreased, the actual ignition angle is advanced than the target ignition angle. Therefore, in the sudden change of the engine speed (RPM), charging starts at the charge start angle calculated at the start of the time segment (Time Segment Start) and the actual ignition angle after the charge time is different from the target ignition angle, And each of the contrast / advance angle leads to unexpected knocking or driving deterioration due to a decrease in output.

In view of the above, the present invention solves the difference between the actual ignition angle and the target ignition angle caused by the abrupt change of the engine speed (RPM) by the ignition charge start angle correction, It is an object of the present invention to provide an ignition coil charge start angle control method in which each control is performed.

According to an aspect of the present invention, there is provided an ignition coil charging start angle control method comprising: (A) ignition at an initial ignition charge time of a set ignition coil, The occurrence of the difference is judged; (B) calculating an actual ignition angle difference value when the difference between the target ignition angle and the actual ignition angle occurs; (C) the initial ignition charge time is corrected to the ignition charge start angle correction value for the actual ignition angle difference value to determine the ignition charge time.

The initial ignition charge time is determined by an initial charge start angle and the initial charge start angle is determined by subtracting the product of the angular velocity and the segment interval including the initial charge time at the target point angle of view. The actual ignition angle difference is calculated by subtracting the actual ignition angle from the target point angle of view. The correction ignition charge time is determined by a charge start angle and the charge start angle is determined by subtracting a value obtained by adding an ignition charge start angle correction value to a product of an angular speed and a segment interval including the initial charge time at a target point angle of view.

(C-1) calculating an acceleration by dividing an initial segment to which the initial ignition charge time is applied and a next segment following the ignition by an initial segment and a next segment interval, and (c-2) (C-3) the ignition angle difference correction value and the ignition charge start angle at which the initial ignition charge time starts are calculated.

The ignition charge start angle correction value is calculated by multiplying the ignition angle difference correction value by the ignition charge start angle.

The present invention eliminates the difference between the actual ignition angle and the target ignition angle caused by the abrupt change in the engine RPM, by using the ignition charge start angle correction, so that the accurate ignition angle control is always performed even in the sudden change in the engine speed .

Further, according to the present invention, the actual ignition angle is adjusted to the target ignition angle under any operating condition, thereby preventing the knocking or the output of the engine from occurring due to the advance / advance of the ignition timing relative to the target ignition angle.

FIG. 1 is a flowchart of an ignition coil charge start angle control method according to the present invention, and FIG. 2 is an example of a time segment diagram for charging an ignition coil according to the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, which illustrate exemplary embodiments of the present invention. The present invention is not limited to these embodiments.

FIG. 1 shows a flowchart of an ignition coil charge start angle control method according to the present embodiment. In addition, Figure 2 is a start segment calculation point (N _n-1) and the next segment calculation starting point (N _n) to establish a T _segment, T _d (charging time between the start of the charge and the target ignition) formed between the T _segment between , definition of θ (ignition angle), θ _{charging start} (charging start angle), θ _{target ignition} (target point angle), θ _difference (ignition angle difference), and acceleration [(N _n -N _n-1 ) / T _segment ] . Therefore, the control logic described below is implemented through an ECU (Engine Control Unit or Electronic Control Unit) and is described in defined terms.

S10 is a step for judging occurrence of the difference between the target ignition angle and the actual ignition angle during engine driving. This is determined by the ECU. To this end, the ECU determines the ignition coil charging time in consideration of the cooling water temperature, the battery condition, and the like, and determines the charging start angle at the start of each cylinder segment in consideration of the engine rotation. In this case, the _start of θ _charging for N _n is defined as the initial charging time and is calculated by the following equation.

Equation: θ _{charge start} = θ _{target ignition} - T _d x ω, where ω is the angular velocity, which is the angular velocity for the rotation of the camshaft or crankshaft which identifies the valve timing.

S20 is a step of calculating the actual ignition angle difference. To do this, the ECU subtracts the actual ignition angle at the target ignition angle, and calculates the ignition angle difference by the difference.

Equation: θ _difference = θ _{target ignition} ?? θ _{Actual ignition} (actual ignition angle)

S30 is a step of calculating the acceleration. For this purpose, the ECU calculates the acceleration by dividing the difference between the start point of the next segment calculation and the start point of the segment calculation by the interval.

Equation: Acceleration = (N _n -N _n-1 ) / T _segment

Step S40 is a step of calculating the ignition angle difference correction value alpha by the acceleration. To this end, the ECU is constructed as a map such that? Is determined by the amount of change in engine speed (RPM). In particular, vehicle acceleration causes ignition delay, while vehicle deceleration causes premature ignition. Therefore, α approaches a small value closer to 0, while has a larger value as it increases in positive or negative direction.

S50 is a step of calculating the ignition charge start angle correction value beta. To do so, the ECU calculates the ignition angle difference by multiplying the ignition angle difference correction value α by the acceleration.

Equation:? =? _Difference x?

S60 is a step of calculating the next segment ignition charge start angle. For this purpose, the ECU reflects β to the previous segment ignition charge start angle.

Equation: θ _{start charge} = θ _{target ignition} - T _d x ω + β

Therefore, in the T _segment defined between T start leads after _{the segment} following the segment calculation point (N _n) and the next segment calculation starting point (N _{n + 1)} is reflected in the ignition angle difference calculated in S10, the therefrom θ _difference The ignition delay or the early ignition in which a sudden change in the engine speed (RPM) due to acceleration or deceleration of the vehicle occurs is prevented.

S70 means that the processes of S10 to S60 are continuously performed by the ECU during engine operation.

As described above, in the ignition coil charging start angle control method according to the present embodiment, the difference between the target ignition angle and the actual ignition angle by the ECU (Engine Control Unit) after ignition at the initial ignition charge time of the set ignition coil And when the difference between the target ignition angle and the actual ignition angle occurs, the initial ignition charge time is corrected to the ignition charge start angle correction value for the actual ignition angle difference value, and the correction ignition charge time is determined so that the abrupt change in the engine speed (RPM) The difference between the actual ignition angle and the target ignition angle generated due to the ignition timing is eliminated, and the ignition angle control is always performed even when the sudden change in engine speed (RPM) is constant.

T _segment : between segment start point (N _n-1 ) and next segment start point (N _n )
T _d : Charge time between charge start and target ignition
θ: Ignition angle θ _{Charging start} : Charging start angle
θ _{Target ignition} : _{Target point} angle of view
θ _difference : ignition angle difference

Claims (6)

(A) a difference between a target ignition angle and an actual ignition angle by an ECU (Engine Control Unit) is determined after ignition is performed at an initial ignition charge time of a set ignition coil;
(B) calculating an actual ignition angle difference value when the difference between the target ignition angle and the actual ignition angle occurs;
(C) correcting the initial ignition charge time with an ignition charge start angle correction value for the actual ignition angle difference value to determine a correction ignition charge time
Wherein the ignition coil charging start angle control method comprises:
The method of claim 1, wherein the initial ignition charge time is determined by an initial charge start angle, and the initial charge start angle is determined by subtracting a product of an angular velocity and a segment interval including the initial charge time at a target point angle of view Wherein the ignition coil charging start angle control method comprises:
2. The ignition coil charging start angle control method according to claim 1, wherein the actual ignition angle difference is calculated by subtracting an actual ignition angle from a target point angle of view in (B).
The method according to claim 1, wherein the corrected ignition charge time is determined as a charge start angle, and the charge start angle is a value obtained by adding an ignition charge start angle correction value to a product of an angular speed and a segment interval including the initial charge time at a target point angle of view The ignition coil charging start angle control method comprising:
The method of claim 1, wherein the ignition charge start angle correction value is calculated by: (c-1) calculating a difference between an initial segment to which the initial ignition charge time is applied and a next segment following the ignition, (C-2) calculating an ignition angle difference correction value based on an acceleration corresponding to the increase or decrease in the engine speed, (c-3) calculating the ignition angle difference correction value and the initial ignition charge time Wherein the ignition charge start angle is calculated as an ignition charge start angle.
The method of claim 5, wherein the ignition charge start angle correction value is calculated by multiplying the ignition angle difference correction value by the ignition charge start angle.

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