KR100264577B1 - Idle speed control method at starting - Google Patents

Abstract

PURPOSE: An idle speed controlling method in case of starting is provided to control an idle controller according to a damping amount and a damping cycle represented by a cooling water temperature in a transition section from a starting duty to a target duty in the beginning of starting, thereby improving the starting performance and increasing the matching freedom of such starting. CONSTITUTION: An idle speed controlling method in case of starting includes the steps of judging an idle rpm damping mode from an engine rpm(S2), patching a duty damping amount according to a current cooling water temperature from a table mapped in advance according to a function of cooling water temperature in case of the idle rpm damping mode(S3), determining a current driving duty by deducting a duty damping amount patched in the second step from a driving duty before a cycle(S4), patching a damping cycle according to a current cooling water temperature from the table mapped in advance according to the cooling water function(S5), driving an idle controller with the driving duty determined in the third step and the damping cycle patched in the fourth step(S6), and determining whether the current driving duty reaches a target duty for returning to the second step to repeat the above steps if not(S7).

Description

Idle speed control method at start-up

1 is a block diagram of a general electronic control engine to which the present invention is applied.

2 is a waveform diagram of a duty signal generated by the control method according to the embodiment of the present invention,

3 is a flowchart illustrating a method of controlling an idle speed at startup according to an embodiment of the present invention.

* Explanation of symbols for main parts of the drawings

1: Throttle Position Sensor 2: Water Temperature Sensor

3: engine speed sensor 4: map sensor

5: idle controller 6: engine control unit

The present invention relates to a start idle speed control method applied to an electronic control engine. More specifically, when the transition from the starting duty of the initial starter to the target duty, the attenuation amount and the decay period are determined as a function of the coolant temperature, By controlling the duty according to this value, the present invention relates to a method of controlling idle speed at start-up that can increase various degrees of freedom of starting and start-up matching.

According to the prior art, the idle controller is driven by the starting duty previously mapped to the engine control unit at the beginning of the start, and after a predetermined time, the idle controller is driven to transition from the starting duty to the target duty.

At this time, the transition from the starting duty to the target duty is performed by allowing the duty to be attenuated by a predetermined amount at a predetermined time period. In this way, when the target duty is reached, the engine speed has a stable idle speed (for example, 800 rpm).

However, the above-described conventional technology has a problem that the starting performance is impaired when the temperature of the cooling water is low, that is, during cold start, and the rotation of the engine is irregular.

Therefore, an object of the present invention is to solve the conventional technical problems as described above, in which attenuation amount and attenuation period are determined by a function expressed in the coolant temperature of the engine in a section transitioning from the starting duty to the target duty at the beginning. The present invention provides a method for controlling idle rotation at start-up that can improve the starting performance and increase the matching degree of freedom at start-up by controlling the operation of the idle controller according to the determined value.

As a means for achieving the above object, the configuration of the start-up idle rotation control method according to a feature of the present invention, the first step of determining whether the idle rotation speed attenuation mode from the engine speed; A second step of fetching a duty attenuation amount according to the temperature of the current coolant from a table previously mapped as a function of the coolant temperature in the idle speed attenuation mode in the first step; A third step of determining a current driving duty by subtracting the duty attenuation amount fetched in the second step from the driving duty before one period; Fetching a decay period according to the temperature of the current coolant from a table previously mapped as a function of coolant temperature; A fifth step of driving the idle controller as the driving duty determined in the third step and the attenuation period fetched in the fourth step; And a sixth step of determining whether the current driving duty has reached the target duty, and if the target duty has not been reached, jumping to the second step so that subsequent steps are repeatedly performed.

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 general electronic control engine to which the present invention is applied, and FIG. 2 is a waveform diagram of a duty signal generated by a control method according to an embodiment of the present invention, and FIG. 3 is an embodiment of the present invention. According to the start-up idle speed control method.

First, the configuration and operation of a general electronic control engine to which the present invention is applied will be described with reference to FIG.

As shown in FIG. 1, a general electronically controlled engine to which the present invention is applied includes: a throttle position sensor 1 installed at a throttle valve of an engine ENG intake passage; An idle controller (5) installed in the pipe formed to bypass the throttle valve; A water temperature sensor 2, an engine speed sensor 3, and a map sensor 4 mounted to the engine; An engine control unit 6 is connected to receive the signal of each sensor and to output a drive signal to the idle controller 5.

When the operation is started by power supply, the position of the throttle valve is detected by the throttle position sensor 1, the temperature of the coolant is detected by the water temperature sensor 2, and the rotation speed of the crankshaft is detected by the engine speed sensor 3. do. In the map sensor 4, the pressure in the intake port is sensed.

In the engine control unit 6, the fuel injection amount and the ignition timing of the engine are controlled using the respective sensor values, and in particular, when the throttle opening degree is 0%, the idle rotation control operation is performed.

When the throttle opening degree is 0%, a predetermined duty signal is generated in the engine control unit 6 by an internal program, and this duty signal is output to the idle controller 5 to control the operation of the idle controller 5. The present invention is applied to a method for controlling a process in which the duty ratio of the duty signal output to the idle controller 5 at the start-up transitions from the start duty to the target duty.

Next, the operation of the idle rotation control method at start-up according to the embodiment of the present invention will be described with reference to the configuration of FIG. 1, the waveform diagram of FIG. 2 and the flowchart of FIG.

When the engine control unit 6 is operated by power supply, the operation of the idle rotation control method according to the embodiment of the present invention is started (S1).

When the operation is started, it is determined whether the engine speed input to the engine control unit 6 has entered the idle speed attenuation mode (S2). This step is to determine whether to reach the initial start duty ISCINI of FIG. 2 to perform the transition operation.

If the idle speed attenuation mode is not in the step S2, the control jumps to step S8 to return control and returns to the main program.

In the step S2, in the idle rotation speed decay mode, the duty attenuation amount corresponding to the current coolant temperature {ISCDECL) from the table on the duty attenuation amount previously mapped to the memory in the engine control unit 6 as a function of the coolant temperature. (WTS)} is fetched (S3). This duty attenuation amount ISCDECL (WTS) is an amount corresponding to B in FIG.

Next, the current driving duty {ISCFIL (i)} is calculated by subtracting the duty attenuation amount ISCDECL (WTS) fetched in step S3 from the driving duty {ISCFIL (i-1) before one cycle). (S4).

Then, a decay period {ACRDEC (WTS)) corresponding to the current coolant temperature is fetched from the table relating to the duty cycle, which is previously mapped to the memory in the engine control unit 6 as a function of the coolant temperature. ACRDEC (WTS)} is the amount corresponding to A of FIG.

The idle controller 5 is driven according to the driving duty {ISCFIL (i)} calculated in the step S4 and the attenuation period ACRDEC (WTS) fetched in the step S3 (S6). That is, the idle controller 5 is driven to a magnitude corresponding to the attenuation period driving duty.

When driving of the idle controller 5 is completed, it is determined whether the target duty has been reached by checking the current driving duty {ISCFIL (i)} (S7). The target duty is the ISCDUT shown in FIG.

If the current driving duty {ISCFIL (i)} does not reach the target duty ISCDUT in step S7, the operation jumps to step S3 to repeat the operation of the subsequent steps, and the current driving duty { If ISCFIL (i)} has reached the target duty ISCDUT, control is returned (S8) and the control returns to the main program.

As described above, according to the exemplary embodiment of the present invention, the starter performance can be improved by controlling the idle controller according to the attenuation amount and the attenuation period expressed as a function of the coolant temperature in the section transitioning from the starting duty to the target duty at the beginning of starting. And increase the matching degree of freedom of starting.

Claims (1)

A first step of determining whether the engine speed is in the idle speed attenuation mode; A second step of fetching a duty attenuation amount according to the temperature of the current coolant from a table previously mapped as a function of the coolant temperature in the idle speed attenuation mode in the first step; A third step of determining a current driving duty by subtracting the duty attenuation amount fetched in the second step from the driving duty before one period; Fetching a decay period according to the current coolant temperature from a table previously mapped as a function of coolant temperature; A fifth step of driving the idle controller as the driving duty determined in the third step and the attenuation period fetched in the fourth step; Determining whether the current driving duty has reached the target duty, and if the target duty has not been reached, including a sixth step to jump to the second step so that subsequent steps are repeatedly performed. Idle rotation control method at start-up.