KR19980053896A - How to calculate the fuel injection volume of the engine - Google Patents

Abstract

The present invention relates to a method for calculating the fuel injection amount of an engine, comprising the steps of: calculating a map sampling time at a predetermined time; and calculating a moving average of the map sampling time for one top dead center in calculating the filling efficiency. Calculating a map filtering value using the map average value and the map sensor offset value, calculating a map using the map filtering value and a map correction amount, and changing a map using the map average value Calculating a fuel injection amount, calculating a basic injection amount using a basic injection amount conversion coefficient, a map, and a filling efficiency correction, and separately calculating each of the corrections using a top dead center and a time task. It includes the step of calculating the final fuel injection amount after the calculation, the filling efficiency calculation in the fuel amount calculation and the performance during the open loop Since separate the calculation relates to a fuel injection amount calculation method of the engine to improve the effective fuel amount calculation and control specification.

Description

How to calculate the fuel injection volume of the engine

The present invention relates to a fuel injection amount calculation method of an engine, and more specifically, to a fuel injection amount calculation method of an engine that enables effective fuel amount calculation because the fuel efficiency calculation is separated from the calculation of the filling efficiency calculation in the fuel amount calculation and the open loop. It is about.

Conventionally, in calculating the fuel injection amount of the engine, it was calculated by integrating the filling efficiency and the air-fuel ratio correction. In addition, in the open loop, the method of calculating the air-fuel ratio correction and the filling efficiency was used.

However, this integrated application method is not only difficult to accurately calculate the fuel injection amount of the engine, but also has a problem that it is not easy to control.

Accordingly, an object of the present invention is to solve the above problems, and provides a method of calculating the fuel injection amount of the engine so that the fuel efficiency calculation and control specification can be improved by separating the filling efficiency calculation and the air-fuel ratio correction calculation during the open loop. It's there.

1 is a block diagram showing a fuel injection amount calculation method of an engine according to an embodiment of the present invention;

2 (a) to 2 (d) are block diagrams illustrating a fuel injection amount correction coefficient and a method for calculating the correction amount according to the embodiment of the present invention.

* Description of the symbols for the main parts of the drawings *

Ktdc: Top dead center treatment total injection rate correction factor

Kitm: Time task processing total injection quantity correction factor

Ttdc: Top dead center fuel correction amount

Ttim: Time task processing total fuel correction amount

INJC: Default injection rate conversion factor MAPOFS: Map sensor offset value

FILMAPC: Acceleration judgment map threshold value K _W : Water temperature correction coefficient

Ka: Intake air temperature correction coefficient Kh: Notice correction coefficient

Kf: Feedback correction coefficient Kaf: Performance ratio correction coefficient

Klm: Learning correction factor Kg: Matching gain

Kas: Correction factor immediately after startup Kt: Correction factor for startup time

Kr: Rewet correction factor Tla: Learning correction amount

Td: Bat correction amount Tacc: Acceleration / deceleration correction amount

In order to achieve the above object, the present invention comprises the steps of: calculating a map sampling time (MAP SAMPLING TIME) every predetermined time in calculating the filling efficiency; Calculating a map average value by calculating a moving average of a map sampling time for one top dead center; Calculating a map filtering value (MAP FILTERING) using the map average value and a map sensor offset value; Calculating a map using the map filtering value and a map correction amount; Calculating a map variation value using the map average value; Calculating a fuel injection amount, the method comprising: calculating a basic injection amount using a basic injection amount change coefficient, a map, and a filling efficiency correction; And calculating the final fuel injection amount after separately calculating each of the corrections by the top dead center and the type task (TIME TASK).

The principle of the fuel injection amount calculation method of the engine according to the embodiment of the present invention configured as described above is as follows.

First, the outline of the specification change is shown in Table 1 below.

TABLE 1

The control process as defined in Table 1 above is well illustrated in the block diagram shown in FIG.

Next, a method of calculating a filling efficiency related to intake measurement and a method of calculating a final fuel injection amount will be described with reference to FIG. 1.

First, with respect to intake measurement, the map sampling type (MAPADC) is set at every 2.5 [ms]. Next, the map sampling time MAPADC for one top dead center TDC is calculated by moving average to calculate the map average value MAPAVG. The calculation process of the map average value MAPAVG is shown in Equation 1 below.

[Equation 1]

MAPAVG = 1/2 ⁿ {MAPADC (n) + AMPADC [n-1) +2 ¹ MAPADC (n-2)... +2 ^n-1 MAPADC (1)}

Next, the map filtering value MAPFIL is calculated using the map average value MAPAVG and the map sensor using the offset value MAPOFSC as shown in Equation 2 below.

[Equation 2]

Next, a map MAP is calculated using the map filtering value MAPIL and a map correction amount CORMAP, and a map variation value MAPDLT is calculated using the map average value MAPAVG. The calculation process is as shown in [Equation 3] and [Equation 4] below.

[Equation 3]

MAP = MAPFIL + CORMAP

[Equation 4]

MAPDLT = MAPAVG (i) -MAPAVG (i-1)

In Equation 3, the map correction amount CORMAP becomes CORACCL (MAPDLT) during acceleration and CORDCCL (MAPDLT) during deceleration.

Next, in calculating the fuel injection amount, the basic injection amount Tb is calculated as shown in [Equation 5] using the basic injection amount conversion factor INJC, the map MAP, and the filling efficiency correction INJCOR. .

[Equation 5]

Tb = INJC, MAP, INJCOR

INJCOR = 0.5 + INJNORM (# RPM030, M MAPFIL) / 256)

Finally, after calculating each of the correction by the top dead center (TDC) and the time task (TIME TASK), the final fuel injection amount (INJWID) is calculated as shown in Equation 6 below.

[Equation 6]

INJWID = TbKtdcKtim + Ttdc + Ttim

A method of calculating the fuel injection amount correction coefficients Ktdc and Ktim and the correction amounts Ttdc and Ttim shown in Equation 6 are shown in FIGS. 2A to 2D.

The filling efficiency calculation method and the final fuel injection amount calculation method as described above are summarized as follows.

1. Separates the conventional integrated applied filling efficiency and air-fuel ratio correction, respectively, and also applies air-fuel ratio correction only for the open loop time.

2. The conventional liquid film delay correction is changed to acceleration / deceleration correction.

3. The map sensor offset value (MAPOFSC) applied when calculating the basic fuel level is applied to the map filtering value (MAPFIL) calculation item.

The effect of the fuel injection amount calculation method of the engine as described above, it is possible to improve the effective fuel amount calculation and control specification because the fuel efficiency calculation and fuel efficiency correction calculation in the open loop is separated.

Claims (5)

Calculating a filling efficiency, the method comprising: calculating a map sampling time (MAP SAMPLING TIME) every predetermined time; Calculating a map average value by calculating a moving average of a map sampling time for one top dead center; Calculating a map filtering value (MAP FILTERING) using the map average value and a map sensor offset value; Calculating a map using the map filtering value and a map correction amount; Calculating a map variation value using the map average value; Calculating a fuel injection amount, the method comprising: calculating a basic injection amount using a basic injection amount conversion coefficient, a map, and a filling efficiency correction; And calculating the final fuel injection amount after separately calculating each of the corrections using a top dead center and a time task. The method of claim 1, wherein the map sampling time is calculated every 2.5 [ms]. The method of claim 1, wherein the filling efficiency and the air-fuel ratio correction are separately calculated. The method of claim 3, wherein the air-fuel ratio correction is applied only in an open loop. The method of claim 1, wherein the map sensor offset value is applied to a map filtering calculation item.