JP2008045506A - Engine control atmospheric pressure correction method and control device therefor - Google Patents

Abstract

[PROBLEMS] To simplify the arithmetic processing for correcting the fuel injection amount and the ignition timing to the atmospheric pressure in the engine control of the speed density system, and to obtain high controllability without requiring high processing capacity in the control device. To.
The engine control for determining the fuel injection amount and the ignition timing using the fuel injection map and the ignition timing map based on the detected intake pipe pressure data and the engine rotational speed data is corrected according to the fluctuation of the atmospheric pressure. In the atmospheric pressure correction method for obtaining the atmospheric pressure corrected fuel injection amount and the atmospheric pressure corrected ignition advance value, the fuel injection map and the ignition timing map are corrected in advance according to the atmospheric pressure. By applying the detected intake pipe pressure data and engine speed data to these maps, the atmospheric pressure corrected fuel injection amount and the atmospheric pressure corrected ignition advance value can be directly obtained. Was what I wanted.
[Selection] Figure 2

Description

  The present invention relates to a method for correcting atmospheric pressure for engine control and a control apparatus therefor, and in particular, in speed-controlled engine control, correction is performed to maintain a smooth engine operating state in accordance with changes in altitude. The present invention relates to an atmospheric pressure correction method for engine control and a control apparatus for the same in order to realize a proper fuel injection amount and ignition timing.

  In the control of the vehicle engine of the speed-dentity method, the intake pipe pressure is detected by the boost sensor, the engine rotation speed is detected by the engine rotation detection sensor, and is determined by the preset engine rotation speed and the intake pipe pressure value. Using the fuel injection map and the ignition timing map, an accurate fuel injection amount and ignition timing at that time are obtained.

  In such speed-dentity-type engine control, when a vehicle equipped with this engine moves from a flat ground to a high ground, it is necessary to reduce fuel in order to ensure the same air-fuel ratio as the flat ground by lowering the atmospheric pressure. is there. Accordingly, it is necessary to further correct the derived fuel injection amount, and it is also necessary to similarly correct the ignition timing in order to prevent a decrease in output torque due to a decrease in atmospheric pressure.

  Therefore, as a means for correcting such atmospheric pressure, as shown in the conceptual diagram of FIG. 3 (A), the control device injects the fuel injection amount once obtained from the map of the correspondence relationship between the intake pipe pressure and the engine speed. The fuel injection amount corrected by the atmospheric pressure is multiplied by the atmospheric pressure correction coefficient, and the advance value obtained from the map is multiplied by the ignition atmospheric pressure correction coefficient as shown in FIG. In general, the advance value is obtained.

  However, adding corrections to both the fuel injection amount and the ignition advance value leads to an increase in the processing load in the control. Therefore, a high processing capacity is required for a control device that needs to execute other processes at the same time. It will be. However, it is disadvantageous in terms of cost to dispose a high-performance control device in a speed-dentity control engine. Therefore, by applying the corrected intake pipe pressure obtained by correcting the detected intake pipe pressure itself to the atmospheric pressure to each map, the fuel injection amount and the ignition timing corresponding to the atmospheric pressure are obtained by one correction process. A method for correcting the atmospheric pressure is proposed in Japanese Patent Laid-Open No. 5-149187.

However, this atmospheric pressure correction method also requires a multiplication procedure to derive the atmospheric pressure correction coefficient for the intake pipe pressure, and further requires a procedure for multiplying this by the actual measured value of the intake pipe pressure. Since a plurality of multiplication procedures are required at the same time, there is a concern that if the processing capability of the control device is not high, control may be delayed and controllability may be impaired.
Japanese Patent Laid-Open No. 5-149187

  The present invention is intended to solve the above-described problems. In the engine control of the speed density method, the arithmetic processing for correcting the fuel injection amount and the ignition timing to the atmospheric pressure is simplified and the control is performed. It is an object of the present invention to obtain high controllability without requiring high processing capability for the apparatus.

  A speed-identity system that determines the fuel injection amount and ignition timing using the fuel injection map data and the ignition timing map data based on the correspondence between the detected intake pipe pressure data and the engine rotational speed data. In engine control, an atmospheric pressure correction method for obtaining an atmospheric pressure corrected fuel injection amount and an atmospheric pressure corrected ignition advance value corrected in accordance with fluctuations in atmospheric pressure, wherein the fuel injection map and ignition timing map are By forming the corresponding relationship between the atmospheric pressure corrected intake pipe pressure corrected in advance according to the atmospheric pressure and the engine rotational speed, and applying the detected intake pipe pressure data and engine rotational speed data to the both maps, The atmospheric pressure corrected fuel injection amount and the atmospheric pressure corrected ignition advance value are directly obtained.

  In this way, by using a map based on the axis of the intake pipe pressure and the axis of the engine speed corrected in advance according to the atmospheric pressure, the atmospheric pressure can be directly adjusted without requiring many complicated procedures such as multiplication. The corrected fuel injection amount and ignition advance value can be obtained.

  Further, if the fuel injection map and the ignition timing map are respectively set in advance for each atmospheric pressure having a predetermined width divided in stages, the map for the atmospheric pressure can be dealt with finely.

  Further, in the above-described atmospheric pressure correction method for engine control, if the axis of the atmospheric pressure correction intake pipe pressure of the map is obtained by adding a predetermined correction value corresponding to the atmospheric pressure to the intake pipe pressure value, Map setting is also relatively easy.

  Furthermore, the engine rotation detection sensor and the boost sensor are connected to detect the engine rotation speed and the intake pipe pressure, and the atmospheric pressure is detected by a predetermined means. A program for executing the method is stored, and the above-described atmospheric pressure correction method can be easily realized only by disposing the control device by executing the engine control atmospheric pressure correction method. It becomes.

  According to the present invention using a map with an intake pipe pressure axis corrected in advance to atmospheric pressure, it is possible to simplify the arithmetic processing for correcting the fuel injection amount and the ignition timing to atmospheric pressure, and to increase the processing capacity of the control device. High controllability can be obtained without necessity.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIG. 1 shows a layout of a control system for a vehicle engine, which is an embodiment of the present invention. The electronic control unit 10 is a control device for executing various controls in the engine, and also serves as a control device for executing the atmospheric pressure correction method for engine control according to the present invention. A program for executing the atmospheric pressure correction method described below is stored.

  The engine speed data from the engine speed detection sensor 2 and the intake pipe pressure data from the boost sensor 3 are input to the electronic control unit 10, and the fuel injection amount and ignition timing are determined based on this data. A so-called speed-identity control system is configured in which a drive signal is output to the injection valve 7 and the igniter 8 to perform control.

  Further, the atmospheric pressure sensor 4 is connected to the electronic control unit 10 to input atmospheric pressure data. Based on this, the atmospheric pressure correction of the fuel injection amount and the ignition timing, which will be described in detail below, is performed. For the procedure to be executed. Even if the atmospheric pressure sensor 4 is not provided, the atmospheric pressure can be estimated and used as atmospheric pressure data by a predetermined method based on the detected intake pipe pressure data.

  Next, the atmospheric pressure correction method for the fuel injection amount and the ignition advance value according to the present embodiment, using the conceptual diagram of the map set in the storage unit of the electronic control unit 10 in FIGS. Details will be described.

  Referring to the map for determining the atmospheric pressure correction fuel injection amount in FIG. 2A, the difference between this map and the map of FIG. This is a point that the axis is an axis of the atmospheric pressure corrected intake pipe pressure corrected in advance to the atmospheric pressure. Thus, the present invention is characterized in that the atmospheric pressure corrected fuel injection amount can be obtained directly only by applying the detected intake pipe pressure data and engine rotational speed data to this map. Therefore, as in the case of FIG. 3A, the trouble of multiplying the fuel injection amount obtained by the map by the correction coefficient based on the detected atmospheric pressure data can be omitted.

  Referring to the map for determining the ignition advance value after atmospheric pressure correction in FIG. 2B, the vertical axis of the intake pipe pressure is the atmospheric pressure in advance as in FIG. 2A. The corrected atmospheric pressure correction intake pipe pressure is used as an axis, and it is possible to directly apply the detected intake pipe pressure data and engine rotational speed data to the map without imposing a large processing load on the electronic control unit 10. The ignition advance value corrected for atmospheric pressure is obtained.

  In both maps, the axis of the atmospheric pressure correction intake pipe pressure can be calculated and set, for example, by adding a correction value corresponding to the atmospheric pressure to the intake pipe pressure value. The correction value corresponding to the atmospheric pressure may be determined by dividing the atmospheric pressure in a stepwise manner and obtaining an optimum value experimentally for each.

  In addition, each map is stored in advance in the storage unit of the electronic control unit 10, but from the assumed actual use of the vehicle engine, the variation range and the step width of the atmospheric pressure are determined and the necessary minimum number is obtained. You only need to remember the map. For example, assuming use in Japan, it is usually sufficient if it can cope with an altitude of about 2000 m, and the range of the atmospheric pressure level is set to a level of, for example, an altitude difference of about 200 to 300 m. it is conceivable that. Then, a map that matches the atmospheric pressure value detected by the electronic control unit 10 may be used to obtain the fuel injection amount and the advance value corrected for atmospheric pressure.

  As described above, according to the present invention, it is possible to greatly simplify the arithmetic processing for correcting the fuel injection amount and the ignition timing to the atmospheric pressure in the engine control by the speed density method, and the control device has a high processing capacity. High controllability can be achieved without requiring

The layout which shows embodiment of this invention. (A) is a conceptual diagram of a map for obtaining an atmospheric pressure corrected fuel injection amount in the present embodiment, (B) is a conceptual diagram of a map for obtaining an atmospheric pressure corrected ignition advance value in the present embodiment, (A) is a conceptual diagram of a map for determining the fuel injection amount and a method for determining the atmospheric pressure corrected fuel injection amount in the conventional example, and (B) is a map for determining the ignition advance value and the atmospheric pressure corrected ignition advance in the conventional example. The conceptual diagram of the method of calculating | requiring a value.

Explanation of symbols

2 Engine rotation detection sensor, 3 Boost sensor, 4 Atmospheric pressure sensor, 7 Fuel injection valve, 8 Igniter, 10 Electronic control unit

Claims (4)

  A speed-identity system that determines the fuel injection amount and ignition timing using the fuel injection map data and the ignition timing map data based on the correspondence between the detected intake pipe pressure data and the engine rotational speed data. In engine control, an atmospheric pressure correction method for obtaining an atmospheric pressure corrected fuel injection amount and an atmospheric pressure corrected ignition advance value corrected in accordance with fluctuations in atmospheric pressure, wherein the fuel injection map and ignition timing map are By forming the corresponding relationship between the atmospheric pressure corrected intake pipe pressure corrected in advance according to the atmospheric pressure and the engine rotational speed, and applying the detected intake pipe pressure data and engine rotational speed data to the both maps, The atmospheric pressure correction of the engine control characterized by directly obtaining the atmospheric pressure correction fuel injection amount and the atmospheric pressure correction ignition advance value Law.   2. The engine-controlled atmospheric pressure correction method according to claim 1, wherein the fuel injection map and the ignition timing map are set in advance for each atmospheric pressure having a predetermined width divided in stages.   The atmospheric pressure correction intake pipe pressure of the fuel injection map and ignition timing map is obtained after adding a predetermined correction value corresponding to the atmospheric pressure to the intake pipe pressure value. Item 3. The engine control atmospheric pressure correction method according to Item 1 or 2. An engine rotation detection sensor and a boost sensor for detecting engine rotation speed and intake pipe pressure, predetermined means for detecting atmospheric pressure, and a program for executing the atmospheric pressure correction method for engine control are stored. 4. A control device for executing the engine control atmospheric pressure correction method according to claim 1, 2 or 3, further comprising storage means.

Images